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2798 lines
107 KiB
2798 lines
107 KiB
/* |
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* copyright (c) 2001 Fabrice Bellard |
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* |
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* This file is part of FFmpeg. |
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* |
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* FFmpeg is free software; you can redistribute it and/or |
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* modify it under the terms of the GNU Lesser General Public |
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* License as published by the Free Software Foundation; either |
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* version 2.1 of the License, or (at your option) any later version. |
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* |
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* FFmpeg is distributed in the hope that it will be useful, |
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* but WITHOUT ANY WARRANTY; without even the implied warranty of |
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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* Lesser General Public License for more details. |
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* |
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* You should have received a copy of the GNU Lesser General Public |
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* License along with FFmpeg; if not, write to the Free Software |
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
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*/ |
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|
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#ifndef AVFORMAT_AVFORMAT_H |
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#define AVFORMAT_AVFORMAT_H |
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/** |
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* @file |
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* @ingroup libavf |
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* Main libavformat public API header |
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*/ |
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|
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/** |
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* @defgroup libavf libavformat |
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* I/O and Muxing/Demuxing Library |
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* |
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* Libavformat (lavf) is a library for dealing with various media container |
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* formats. Its main two purposes are demuxing - i.e. splitting a media file |
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* into component streams, and the reverse process of muxing - writing supplied |
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* data in a specified container format. It also has an @ref lavf_io |
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* "I/O module" which supports a number of protocols for accessing the data (e.g. |
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* file, tcp, http and others). |
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* Unless you are absolutely sure you won't use libavformat's network |
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* capabilities, you should also call avformat_network_init(). |
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* |
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* A supported input format is described by an AVInputFormat struct, conversely |
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* an output format is described by AVOutputFormat. You can iterate over all |
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* input/output formats using the av_demuxer_iterate / av_muxer_iterate() functions. |
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* The protocols layer is not part of the public API, so you can only get the names |
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* of supported protocols with the avio_enum_protocols() function. |
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* |
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* Main lavf structure used for both muxing and demuxing is AVFormatContext, |
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* which exports all information about the file being read or written. As with |
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* most Libavformat structures, its size is not part of public ABI, so it cannot be |
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* allocated on stack or directly with av_malloc(). To create an |
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* AVFormatContext, use avformat_alloc_context() (some functions, like |
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* avformat_open_input() might do that for you). |
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* |
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* Most importantly an AVFormatContext contains: |
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* @li the @ref AVFormatContext.iformat "input" or @ref AVFormatContext.oformat |
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* "output" format. It is either autodetected or set by user for input; |
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* always set by user for output. |
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* @li an @ref AVFormatContext.streams "array" of AVStreams, which describe all |
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* elementary streams stored in the file. AVStreams are typically referred to |
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* using their index in this array. |
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* @li an @ref AVFormatContext.pb "I/O context". It is either opened by lavf or |
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* set by user for input, always set by user for output (unless you are dealing |
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* with an AVFMT_NOFILE format). |
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* |
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* @section lavf_options Passing options to (de)muxers |
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* It is possible to configure lavf muxers and demuxers using the @ref avoptions |
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* mechanism. Generic (format-independent) libavformat options are provided by |
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* AVFormatContext, they can be examined from a user program by calling |
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* av_opt_next() / av_opt_find() on an allocated AVFormatContext (or its AVClass |
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* from avformat_get_class()). Private (format-specific) options are provided by |
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* AVFormatContext.priv_data if and only if AVInputFormat.priv_class / |
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* AVOutputFormat.priv_class of the corresponding format struct is non-NULL. |
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* Further options may be provided by the @ref AVFormatContext.pb "I/O context", |
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* if its AVClass is non-NULL, and the protocols layer. See the discussion on |
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* nesting in @ref avoptions documentation to learn how to access those. |
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* |
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* @section urls |
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* URL strings in libavformat are made of a scheme/protocol, a ':', and a |
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* scheme specific string. URLs without a scheme and ':' used for local files |
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* are supported but deprecated. "file:" should be used for local files. |
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* |
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* It is important that the scheme string is not taken from untrusted |
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* sources without checks. |
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* |
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* Note that some schemes/protocols are quite powerful, allowing access to |
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* both local and remote files, parts of them, concatenations of them, local |
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* audio and video devices and so on. |
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* |
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* @{ |
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* |
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* @defgroup lavf_decoding Demuxing |
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* @{ |
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* Demuxers read a media file and split it into chunks of data (@em packets). A |
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* @ref AVPacket "packet" contains one or more encoded frames which belongs to a |
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* single elementary stream. In the lavf API this process is represented by the |
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* avformat_open_input() function for opening a file, av_read_frame() for |
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* reading a single packet and finally avformat_close_input(), which does the |
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* cleanup. |
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* |
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* @section lavf_decoding_open Opening a media file |
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* The minimum information required to open a file is its URL, which |
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* is passed to avformat_open_input(), as in the following code: |
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* @code |
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* const char *url = "file:in.mp3"; |
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* AVFormatContext *s = NULL; |
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* int ret = avformat_open_input(&s, url, NULL, NULL); |
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* if (ret < 0) |
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* abort(); |
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* @endcode |
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* The above code attempts to allocate an AVFormatContext, open the |
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* specified file (autodetecting the format) and read the header, exporting the |
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* information stored there into s. Some formats do not have a header or do not |
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* store enough information there, so it is recommended that you call the |
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* avformat_find_stream_info() function which tries to read and decode a few |
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* frames to find missing information. |
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* |
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* In some cases you might want to preallocate an AVFormatContext yourself with |
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* avformat_alloc_context() and do some tweaking on it before passing it to |
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* avformat_open_input(). One such case is when you want to use custom functions |
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* for reading input data instead of lavf internal I/O layer. |
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* To do that, create your own AVIOContext with avio_alloc_context(), passing |
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* your reading callbacks to it. Then set the @em pb field of your |
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* AVFormatContext to newly created AVIOContext. |
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* |
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* Since the format of the opened file is in general not known until after |
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* avformat_open_input() has returned, it is not possible to set demuxer private |
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* options on a preallocated context. Instead, the options should be passed to |
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* avformat_open_input() wrapped in an AVDictionary: |
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* @code |
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* AVDictionary *options = NULL; |
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* av_dict_set(&options, "video_size", "640x480", 0); |
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* av_dict_set(&options, "pixel_format", "rgb24", 0); |
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* |
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* if (avformat_open_input(&s, url, NULL, &options) < 0) |
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* abort(); |
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* av_dict_free(&options); |
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* @endcode |
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* This code passes the private options 'video_size' and 'pixel_format' to the |
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* demuxer. They would be necessary for e.g. the rawvideo demuxer, since it |
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* cannot know how to interpret raw video data otherwise. If the format turns |
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* out to be something different than raw video, those options will not be |
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* recognized by the demuxer and therefore will not be applied. Such unrecognized |
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* options are then returned in the options dictionary (recognized options are |
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* consumed). The calling program can handle such unrecognized options as it |
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* wishes, e.g. |
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* @code |
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* AVDictionaryEntry *e; |
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* if (e = av_dict_get(options, "", NULL, AV_DICT_IGNORE_SUFFIX)) { |
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* fprintf(stderr, "Option %s not recognized by the demuxer.\n", e->key); |
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* abort(); |
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* } |
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* @endcode |
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* |
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* After you have finished reading the file, you must close it with |
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* avformat_close_input(). It will free everything associated with the file. |
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* |
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* @section lavf_decoding_read Reading from an opened file |
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* Reading data from an opened AVFormatContext is done by repeatedly calling |
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* av_read_frame() on it. Each call, if successful, will return an AVPacket |
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* containing encoded data for one AVStream, identified by |
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* AVPacket.stream_index. This packet may be passed straight into the libavcodec |
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* decoding functions avcodec_send_packet() or avcodec_decode_subtitle2() if the |
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* caller wishes to decode the data. |
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* |
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* AVPacket.pts, AVPacket.dts and AVPacket.duration timing information will be |
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* set if known. They may also be unset (i.e. AV_NOPTS_VALUE for |
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* pts/dts, 0 for duration) if the stream does not provide them. The timing |
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* information will be in AVStream.time_base units, i.e. it has to be |
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* multiplied by the timebase to convert them to seconds. |
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* |
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* A packet returned by av_read_frame() is always reference-counted, |
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* i.e. AVPacket.buf is set and the user may keep it indefinitely. |
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* The packet must be freed with av_packet_unref() when it is no |
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* longer needed. |
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* |
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* @section lavf_decoding_seek Seeking |
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* @} |
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* |
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* @defgroup lavf_encoding Muxing |
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* @{ |
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* Muxers take encoded data in the form of @ref AVPacket "AVPackets" and write |
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* it into files or other output bytestreams in the specified container format. |
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* |
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* The main API functions for muxing are avformat_write_header() for writing the |
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* file header, av_write_frame() / av_interleaved_write_frame() for writing the |
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* packets and av_write_trailer() for finalizing the file. |
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* |
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* At the beginning of the muxing process, the caller must first call |
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* avformat_alloc_context() to create a muxing context. The caller then sets up |
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* the muxer by filling the various fields in this context: |
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* |
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* - The @ref AVFormatContext.oformat "oformat" field must be set to select the |
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* muxer that will be used. |
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* - Unless the format is of the AVFMT_NOFILE type, the @ref AVFormatContext.pb |
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* "pb" field must be set to an opened IO context, either returned from |
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* avio_open2() or a custom one. |
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* - Unless the format is of the AVFMT_NOSTREAMS type, at least one stream must |
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* be created with the avformat_new_stream() function. The caller should fill |
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* the @ref AVStream.codecpar "stream codec parameters" information, such as the |
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* codec @ref AVCodecParameters.codec_type "type", @ref AVCodecParameters.codec_id |
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* "id" and other parameters (e.g. width / height, the pixel or sample format, |
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* etc.) as known. The @ref AVStream.time_base "stream timebase" should |
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* be set to the timebase that the caller desires to use for this stream (note |
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* that the timebase actually used by the muxer can be different, as will be |
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* described later). |
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* - It is advised to manually initialize only the relevant fields in |
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* AVCodecParameters, rather than using @ref avcodec_parameters_copy() during |
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* remuxing: there is no guarantee that the codec context values remain valid |
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* for both input and output format contexts. |
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* - The caller may fill in additional information, such as @ref |
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* AVFormatContext.metadata "global" or @ref AVStream.metadata "per-stream" |
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* metadata, @ref AVFormatContext.chapters "chapters", @ref |
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* AVFormatContext.programs "programs", etc. as described in the |
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* AVFormatContext documentation. Whether such information will actually be |
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* stored in the output depends on what the container format and the muxer |
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* support. |
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* |
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* When the muxing context is fully set up, the caller must call |
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* avformat_write_header() to initialize the muxer internals and write the file |
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* header. Whether anything actually is written to the IO context at this step |
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* depends on the muxer, but this function must always be called. Any muxer |
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* private options must be passed in the options parameter to this function. |
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* |
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* The data is then sent to the muxer by repeatedly calling av_write_frame() or |
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* av_interleaved_write_frame() (consult those functions' documentation for |
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* discussion on the difference between them; only one of them may be used with |
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* a single muxing context, they should not be mixed). Do note that the timing |
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* information on the packets sent to the muxer must be in the corresponding |
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* AVStream's timebase. That timebase is set by the muxer (in the |
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* avformat_write_header() step) and may be different from the timebase |
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* requested by the caller. |
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* |
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* Once all the data has been written, the caller must call av_write_trailer() |
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* to flush any buffered packets and finalize the output file, then close the IO |
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* context (if any) and finally free the muxing context with |
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* avformat_free_context(). |
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* @} |
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* |
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* @defgroup lavf_io I/O Read/Write |
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* @{ |
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* @section lavf_io_dirlist Directory listing |
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* The directory listing API makes it possible to list files on remote servers. |
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* |
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* Some of possible use cases: |
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* - an "open file" dialog to choose files from a remote location, |
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* - a recursive media finder providing a player with an ability to play all |
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* files from a given directory. |
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* |
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* @subsection lavf_io_dirlist_open Opening a directory |
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* At first, a directory needs to be opened by calling avio_open_dir() |
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* supplied with a URL and, optionally, ::AVDictionary containing |
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* protocol-specific parameters. The function returns zero or positive |
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* integer and allocates AVIODirContext on success. |
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* |
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* @code |
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* AVIODirContext *ctx = NULL; |
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* if (avio_open_dir(&ctx, "smb://example.com/some_dir", NULL) < 0) { |
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* fprintf(stderr, "Cannot open directory.\n"); |
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* abort(); |
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* } |
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* @endcode |
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* |
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* This code tries to open a sample directory using smb protocol without |
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* any additional parameters. |
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* |
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* @subsection lavf_io_dirlist_read Reading entries |
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* Each directory's entry (i.e. file, another directory, anything else |
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* within ::AVIODirEntryType) is represented by AVIODirEntry. |
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* Reading consecutive entries from an opened AVIODirContext is done by |
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* repeatedly calling avio_read_dir() on it. Each call returns zero or |
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* positive integer if successful. Reading can be stopped right after the |
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* NULL entry has been read -- it means there are no entries left to be |
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* read. The following code reads all entries from a directory associated |
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* with ctx and prints their names to standard output. |
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* @code |
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* AVIODirEntry *entry = NULL; |
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* for (;;) { |
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* if (avio_read_dir(ctx, &entry) < 0) { |
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* fprintf(stderr, "Cannot list directory.\n"); |
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* abort(); |
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* } |
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* if (!entry) |
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* break; |
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* printf("%s\n", entry->name); |
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* avio_free_directory_entry(&entry); |
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* } |
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* @endcode |
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* @} |
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* |
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* @defgroup lavf_codec Demuxers |
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* @{ |
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* @defgroup lavf_codec_native Native Demuxers |
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* @{ |
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* @} |
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* @defgroup lavf_codec_wrappers External library wrappers |
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* @{ |
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* @} |
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* @} |
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* @defgroup lavf_protos I/O Protocols |
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* @{ |
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* @} |
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* @defgroup lavf_internal Internal |
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* @{ |
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* @} |
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* @} |
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*/ |
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#include <time.h> |
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#include <stdio.h> /* FILE */ |
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#include "libavcodec/avcodec.h" |
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#include "libavutil/dict.h" |
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#include "libavutil/log.h" |
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#include "avio.h" |
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#include "libavformat/version.h" |
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struct AVFormatContext; |
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struct AVDeviceInfoList; |
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struct AVDeviceCapabilitiesQuery; |
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/** |
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* @defgroup metadata_api Public Metadata API |
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* @{ |
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* @ingroup libavf |
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* The metadata API allows libavformat to export metadata tags to a client |
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* application when demuxing. Conversely it allows a client application to |
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* set metadata when muxing. |
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* |
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* Metadata is exported or set as pairs of key/value strings in the 'metadata' |
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* fields of the AVFormatContext, AVStream, AVChapter and AVProgram structs |
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* using the @ref lavu_dict "AVDictionary" API. Like all strings in FFmpeg, |
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* metadata is assumed to be UTF-8 encoded Unicode. Note that metadata |
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* exported by demuxers isn't checked to be valid UTF-8 in most cases. |
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* |
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* Important concepts to keep in mind: |
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* - Keys are unique; there can never be 2 tags with the same key. This is |
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* also meant semantically, i.e., a demuxer should not knowingly produce |
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* several keys that are literally different but semantically identical. |
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* E.g., key=Author5, key=Author6. In this example, all authors must be |
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* placed in the same tag. |
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* - Metadata is flat, not hierarchical; there are no subtags. If you |
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* want to store, e.g., the email address of the child of producer Alice |
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* and actor Bob, that could have key=alice_and_bobs_childs_email_address. |
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* - Several modifiers can be applied to the tag name. This is done by |
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* appending a dash character ('-') and the modifier name in the order |
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* they appear in the list below -- e.g. foo-eng-sort, not foo-sort-eng. |
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* - language -- a tag whose value is localized for a particular language |
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* is appended with the ISO 639-2/B 3-letter language code. |
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* For example: Author-ger=Michael, Author-eng=Mike |
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* The original/default language is in the unqualified "Author" tag. |
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* A demuxer should set a default if it sets any translated tag. |
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* - sorting -- a modified version of a tag that should be used for |
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* sorting will have '-sort' appended. E.g. artist="The Beatles", |
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* artist-sort="Beatles, The". |
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* - Some protocols and demuxers support metadata updates. After a successful |
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* call to av_read_frame(), AVFormatContext.event_flags or AVStream.event_flags |
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* will be updated to indicate if metadata changed. In order to detect metadata |
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* changes on a stream, you need to loop through all streams in the AVFormatContext |
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* and check their individual event_flags. |
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* |
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* - Demuxers attempt to export metadata in a generic format, however tags |
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* with no generic equivalents are left as they are stored in the container. |
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* Follows a list of generic tag names: |
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* |
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@verbatim |
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album -- name of the set this work belongs to |
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album_artist -- main creator of the set/album, if different from artist. |
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e.g. "Various Artists" for compilation albums. |
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artist -- main creator of the work |
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comment -- any additional description of the file. |
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composer -- who composed the work, if different from artist. |
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copyright -- name of copyright holder. |
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creation_time-- date when the file was created, preferably in ISO 8601. |
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date -- date when the work was created, preferably in ISO 8601. |
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disc -- number of a subset, e.g. disc in a multi-disc collection. |
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encoder -- name/settings of the software/hardware that produced the file. |
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encoded_by -- person/group who created the file. |
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filename -- original name of the file. |
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genre -- <self-evident>. |
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language -- main language in which the work is performed, preferably |
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in ISO 639-2 format. Multiple languages can be specified by |
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separating them with commas. |
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performer -- artist who performed the work, if different from artist. |
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E.g for "Also sprach Zarathustra", artist would be "Richard |
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Strauss" and performer "London Philharmonic Orchestra". |
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publisher -- name of the label/publisher. |
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service_name -- name of the service in broadcasting (channel name). |
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service_provider -- name of the service provider in broadcasting. |
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title -- name of the work. |
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track -- number of this work in the set, can be in form current/total. |
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variant_bitrate -- the total bitrate of the bitrate variant that the current stream is part of |
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@endverbatim |
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* |
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* Look in the examples section for an application example how to use the Metadata API. |
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* |
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* @} |
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*/ |
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|
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/* packet functions */ |
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/** |
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* Allocate and read the payload of a packet and initialize its |
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* fields with default values. |
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* |
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* @param s associated IO context |
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* @param pkt packet |
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* @param size desired payload size |
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* @return >0 (read size) if OK, AVERROR_xxx otherwise |
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*/ |
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int av_get_packet(AVIOContext *s, AVPacket *pkt, int size); |
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|
|
|
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/** |
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* Read data and append it to the current content of the AVPacket. |
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* If pkt->size is 0 this is identical to av_get_packet. |
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* Note that this uses av_grow_packet and thus involves a realloc |
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* which is inefficient. Thus this function should only be used |
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* when there is no reasonable way to know (an upper bound of) |
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* the final size. |
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* |
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* @param s associated IO context |
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* @param pkt packet |
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* @param size amount of data to read |
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* @return >0 (read size) if OK, AVERROR_xxx otherwise, previous data |
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* will not be lost even if an error occurs. |
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*/ |
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int av_append_packet(AVIOContext *s, AVPacket *pkt, int size); |
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|
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/*************************************************/ |
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/* input/output formats */ |
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|
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struct AVCodecTag; |
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|
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/** |
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* This structure contains the data a format has to probe a file. |
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*/ |
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typedef struct AVProbeData { |
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const char *filename; |
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unsigned char *buf; /**< Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero. */ |
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int buf_size; /**< Size of buf except extra allocated bytes */ |
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const char *mime_type; /**< mime_type, when known. */ |
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} AVProbeData; |
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|
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#define AVPROBE_SCORE_RETRY (AVPROBE_SCORE_MAX/4) |
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#define AVPROBE_SCORE_STREAM_RETRY (AVPROBE_SCORE_MAX/4-1) |
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|
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#define AVPROBE_SCORE_EXTENSION 50 ///< score for file extension |
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#define AVPROBE_SCORE_MIME 75 ///< score for file mime type |
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#define AVPROBE_SCORE_MAX 100 ///< maximum score |
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|
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#define AVPROBE_PADDING_SIZE 32 ///< extra allocated bytes at the end of the probe buffer |
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|
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/// Demuxer will use avio_open, no opened file should be provided by the caller. |
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#define AVFMT_NOFILE 0x0001 |
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#define AVFMT_NEEDNUMBER 0x0002 /**< Needs '%d' in filename. */ |
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#define AVFMT_SHOW_IDS 0x0008 /**< Show format stream IDs numbers. */ |
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#define AVFMT_GLOBALHEADER 0x0040 /**< Format wants global header. */ |
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#define AVFMT_NOTIMESTAMPS 0x0080 /**< Format does not need / have any timestamps. */ |
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#define AVFMT_GENERIC_INDEX 0x0100 /**< Use generic index building code. */ |
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#define AVFMT_TS_DISCONT 0x0200 /**< Format allows timestamp discontinuities. Note, muxers always require valid (monotone) timestamps */ |
|
#define AVFMT_VARIABLE_FPS 0x0400 /**< Format allows variable fps. */ |
|
#define AVFMT_NODIMENSIONS 0x0800 /**< Format does not need width/height */ |
|
#define AVFMT_NOSTREAMS 0x1000 /**< Format does not require any streams */ |
|
#define AVFMT_NOBINSEARCH 0x2000 /**< Format does not allow to fall back on binary search via read_timestamp */ |
|
#define AVFMT_NOGENSEARCH 0x4000 /**< Format does not allow to fall back on generic search */ |
|
#define AVFMT_NO_BYTE_SEEK 0x8000 /**< Format does not allow seeking by bytes */ |
|
#define AVFMT_ALLOW_FLUSH 0x10000 /**< Format allows flushing. If not set, the muxer will not receive a NULL packet in the write_packet function. */ |
|
#define AVFMT_TS_NONSTRICT 0x20000 /**< Format does not require strictly |
|
increasing timestamps, but they must |
|
still be monotonic */ |
|
#define AVFMT_TS_NEGATIVE 0x40000 /**< Format allows muxing negative |
|
timestamps. If not set the timestamp |
|
will be shifted in av_write_frame and |
|
av_interleaved_write_frame so they |
|
start from 0. |
|
The user or muxer can override this through |
|
AVFormatContext.avoid_negative_ts |
|
*/ |
|
|
|
#define AVFMT_SEEK_TO_PTS 0x4000000 /**< Seeking is based on PTS */ |
|
|
|
/** |
|
* @addtogroup lavf_encoding |
|
* @{ |
|
*/ |
|
typedef struct AVOutputFormat { |
|
const char *name; |
|
/** |
|
* Descriptive name for the format, meant to be more human-readable |
|
* than name. You should use the NULL_IF_CONFIG_SMALL() macro |
|
* to define it. |
|
*/ |
|
const char *long_name; |
|
const char *mime_type; |
|
const char *extensions; /**< comma-separated filename extensions */ |
|
/* output support */ |
|
enum AVCodecID audio_codec; /**< default audio codec */ |
|
enum AVCodecID video_codec; /**< default video codec */ |
|
enum AVCodecID subtitle_codec; /**< default subtitle codec */ |
|
/** |
|
* can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, |
|
* AVFMT_GLOBALHEADER, AVFMT_NOTIMESTAMPS, AVFMT_VARIABLE_FPS, |
|
* AVFMT_NODIMENSIONS, AVFMT_NOSTREAMS, AVFMT_ALLOW_FLUSH, |
|
* AVFMT_TS_NONSTRICT, AVFMT_TS_NEGATIVE |
|
*/ |
|
int flags; |
|
|
|
/** |
|
* List of supported codec_id-codec_tag pairs, ordered by "better |
|
* choice first". The arrays are all terminated by AV_CODEC_ID_NONE. |
|
*/ |
|
const struct AVCodecTag * const *codec_tag; |
|
|
|
|
|
const AVClass *priv_class; ///< AVClass for the private context |
|
|
|
/***************************************************************** |
|
* No fields below this line are part of the public API. They |
|
* may not be used outside of libavformat and can be changed and |
|
* removed at will. |
|
* New public fields should be added right above. |
|
***************************************************************** |
|
*/ |
|
/** |
|
* size of private data so that it can be allocated in the wrapper |
|
*/ |
|
int priv_data_size; |
|
|
|
int (*write_header)(struct AVFormatContext *); |
|
/** |
|
* Write a packet. If AVFMT_ALLOW_FLUSH is set in flags, |
|
* pkt can be NULL in order to flush data buffered in the muxer. |
|
* When flushing, return 0 if there still is more data to flush, |
|
* or 1 if everything was flushed and there is no more buffered |
|
* data. |
|
*/ |
|
int (*write_packet)(struct AVFormatContext *, AVPacket *pkt); |
|
int (*write_trailer)(struct AVFormatContext *); |
|
/** |
|
* A format-specific function for interleavement. |
|
* If unset, packets will be interleaved by dts. |
|
*/ |
|
int (*interleave_packet)(struct AVFormatContext *, AVPacket *out, |
|
AVPacket *in, int flush); |
|
/** |
|
* Test if the given codec can be stored in this container. |
|
* |
|
* @return 1 if the codec is supported, 0 if it is not. |
|
* A negative number if unknown. |
|
* MKTAG('A', 'P', 'I', 'C') if the codec is only supported as AV_DISPOSITION_ATTACHED_PIC |
|
*/ |
|
int (*query_codec)(enum AVCodecID id, int std_compliance); |
|
|
|
void (*get_output_timestamp)(struct AVFormatContext *s, int stream, |
|
int64_t *dts, int64_t *wall); |
|
/** |
|
* Allows sending messages from application to device. |
|
*/ |
|
int (*control_message)(struct AVFormatContext *s, int type, |
|
void *data, size_t data_size); |
|
|
|
/** |
|
* Write an uncoded AVFrame. |
|
* |
|
* See av_write_uncoded_frame() for details. |
|
* |
|
* The library will free *frame afterwards, but the muxer can prevent it |
|
* by setting the pointer to NULL. |
|
*/ |
|
int (*write_uncoded_frame)(struct AVFormatContext *, int stream_index, |
|
AVFrame **frame, unsigned flags); |
|
/** |
|
* Returns device list with it properties. |
|
* @see avdevice_list_devices() for more details. |
|
*/ |
|
int (*get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list); |
|
enum AVCodecID data_codec; /**< default data codec */ |
|
/** |
|
* Initialize format. May allocate data here, and set any AVFormatContext or |
|
* AVStream parameters that need to be set before packets are sent. |
|
* This method must not write output. |
|
* |
|
* Return 0 if streams were fully configured, 1 if not, negative AVERROR on failure |
|
* |
|
* Any allocations made here must be freed in deinit(). |
|
*/ |
|
int (*init)(struct AVFormatContext *); |
|
/** |
|
* Deinitialize format. If present, this is called whenever the muxer is being |
|
* destroyed, regardless of whether or not the header has been written. |
|
* |
|
* If a trailer is being written, this is called after write_trailer(). |
|
* |
|
* This is called if init() fails as well. |
|
*/ |
|
void (*deinit)(struct AVFormatContext *); |
|
/** |
|
* Set up any necessary bitstream filtering and extract any extra data needed |
|
* for the global header. |
|
* Return 0 if more packets from this stream must be checked; 1 if not. |
|
*/ |
|
int (*check_bitstream)(struct AVFormatContext *, const AVPacket *pkt); |
|
} AVOutputFormat; |
|
/** |
|
* @} |
|
*/ |
|
|
|
/** |
|
* @addtogroup lavf_decoding |
|
* @{ |
|
*/ |
|
typedef struct AVInputFormat { |
|
/** |
|
* A comma separated list of short names for the format. New names |
|
* may be appended with a minor bump. |
|
*/ |
|
const char *name; |
|
|
|
/** |
|
* Descriptive name for the format, meant to be more human-readable |
|
* than name. You should use the NULL_IF_CONFIG_SMALL() macro |
|
* to define it. |
|
*/ |
|
const char *long_name; |
|
|
|
/** |
|
* Can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_SHOW_IDS, |
|
* AVFMT_NOTIMESTAMPS, AVFMT_GENERIC_INDEX, AVFMT_TS_DISCONT, AVFMT_NOBINSEARCH, |
|
* AVFMT_NOGENSEARCH, AVFMT_NO_BYTE_SEEK, AVFMT_SEEK_TO_PTS. |
|
*/ |
|
int flags; |
|
|
|
/** |
|
* If extensions are defined, then no probe is done. You should |
|
* usually not use extension format guessing because it is not |
|
* reliable enough |
|
*/ |
|
const char *extensions; |
|
|
|
const struct AVCodecTag * const *codec_tag; |
|
|
|
const AVClass *priv_class; ///< AVClass for the private context |
|
|
|
/** |
|
* Comma-separated list of mime types. |
|
* It is used check for matching mime types while probing. |
|
* @see av_probe_input_format2 |
|
*/ |
|
const char *mime_type; |
|
|
|
/***************************************************************** |
|
* No fields below this line are part of the public API. They |
|
* may not be used outside of libavformat and can be changed and |
|
* removed at will. |
|
* New public fields should be added right above. |
|
***************************************************************** |
|
*/ |
|
/** |
|
* Raw demuxers store their codec ID here. |
|
*/ |
|
int raw_codec_id; |
|
|
|
/** |
|
* Size of private data so that it can be allocated in the wrapper. |
|
*/ |
|
int priv_data_size; |
|
|
|
/** |
|
* Tell if a given file has a chance of being parsed as this format. |
|
* The buffer provided is guaranteed to be AVPROBE_PADDING_SIZE bytes |
|
* big so you do not have to check for that unless you need more. |
|
*/ |
|
int (*read_probe)(const AVProbeData *); |
|
|
|
/** |
|
* Read the format header and initialize the AVFormatContext |
|
* structure. Return 0 if OK. 'avformat_new_stream' should be |
|
* called to create new streams. |
|
*/ |
|
int (*read_header)(struct AVFormatContext *); |
|
|
|
/** |
|
* Read one packet and put it in 'pkt'. pts and flags are also |
|
* set. 'avformat_new_stream' can be called only if the flag |
|
* AVFMTCTX_NOHEADER is used and only in the calling thread (not in a |
|
* background thread). |
|
* @return 0 on success, < 0 on error. |
|
* Upon returning an error, pkt must be unreferenced by the caller. |
|
*/ |
|
int (*read_packet)(struct AVFormatContext *, AVPacket *pkt); |
|
|
|
/** |
|
* Close the stream. The AVFormatContext and AVStreams are not |
|
* freed by this function |
|
*/ |
|
int (*read_close)(struct AVFormatContext *); |
|
|
|
/** |
|
* Seek to a given timestamp relative to the frames in |
|
* stream component stream_index. |
|
* @param stream_index Must not be -1. |
|
* @param flags Selects which direction should be preferred if no exact |
|
* match is available. |
|
* @return >= 0 on success (but not necessarily the new offset) |
|
*/ |
|
int (*read_seek)(struct AVFormatContext *, |
|
int stream_index, int64_t timestamp, int flags); |
|
|
|
/** |
|
* Get the next timestamp in stream[stream_index].time_base units. |
|
* @return the timestamp or AV_NOPTS_VALUE if an error occurred |
|
*/ |
|
int64_t (*read_timestamp)(struct AVFormatContext *s, int stream_index, |
|
int64_t *pos, int64_t pos_limit); |
|
|
|
/** |
|
* Start/resume playing - only meaningful if using a network-based format |
|
* (RTSP). |
|
*/ |
|
int (*read_play)(struct AVFormatContext *); |
|
|
|
/** |
|
* Pause playing - only meaningful if using a network-based format |
|
* (RTSP). |
|
*/ |
|
int (*read_pause)(struct AVFormatContext *); |
|
|
|
/** |
|
* Seek to timestamp ts. |
|
* Seeking will be done so that the point from which all active streams |
|
* can be presented successfully will be closest to ts and within min/max_ts. |
|
* Active streams are all streams that have AVStream.discard < AVDISCARD_ALL. |
|
*/ |
|
int (*read_seek2)(struct AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags); |
|
|
|
/** |
|
* Returns device list with it properties. |
|
* @see avdevice_list_devices() for more details. |
|
*/ |
|
int (*get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list); |
|
|
|
} AVInputFormat; |
|
/** |
|
* @} |
|
*/ |
|
|
|
enum AVStreamParseType { |
|
AVSTREAM_PARSE_NONE, |
|
AVSTREAM_PARSE_FULL, /**< full parsing and repack */ |
|
AVSTREAM_PARSE_HEADERS, /**< Only parse headers, do not repack. */ |
|
AVSTREAM_PARSE_TIMESTAMPS, /**< full parsing and interpolation of timestamps for frames not starting on a packet boundary */ |
|
AVSTREAM_PARSE_FULL_ONCE, /**< full parsing and repack of the first frame only, only implemented for H.264 currently */ |
|
AVSTREAM_PARSE_FULL_RAW, /**< full parsing and repack with timestamp and position generation by parser for raw |
|
this assumes that each packet in the file contains no demuxer level headers and |
|
just codec level data, otherwise position generation would fail */ |
|
}; |
|
|
|
typedef struct AVIndexEntry { |
|
int64_t pos; |
|
int64_t timestamp; /**< |
|
* Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are available |
|
* when seeking to this entry. That means preferable PTS on keyframe based formats. |
|
* But demuxers can choose to store a different timestamp, if it is more convenient for the implementation or nothing better |
|
* is known |
|
*/ |
|
#define AVINDEX_KEYFRAME 0x0001 |
|
#define AVINDEX_DISCARD_FRAME 0x0002 /** |
|
* Flag is used to indicate which frame should be discarded after decoding. |
|
*/ |
|
int flags:2; |
|
int size:30; //Yeah, trying to keep the size of this small to reduce memory requirements (it is 24 vs. 32 bytes due to possible 8-byte alignment). |
|
int min_distance; /**< Minimum distance between this and the previous keyframe, used to avoid unneeded searching. */ |
|
} AVIndexEntry; |
|
|
|
#define AV_DISPOSITION_DEFAULT 0x0001 |
|
#define AV_DISPOSITION_DUB 0x0002 |
|
#define AV_DISPOSITION_ORIGINAL 0x0004 |
|
#define AV_DISPOSITION_COMMENT 0x0008 |
|
#define AV_DISPOSITION_LYRICS 0x0010 |
|
#define AV_DISPOSITION_KARAOKE 0x0020 |
|
|
|
/** |
|
* Track should be used during playback by default. |
|
* Useful for subtitle track that should be displayed |
|
* even when user did not explicitly ask for subtitles. |
|
*/ |
|
#define AV_DISPOSITION_FORCED 0x0040 |
|
#define AV_DISPOSITION_HEARING_IMPAIRED 0x0080 /**< stream for hearing impaired audiences */ |
|
#define AV_DISPOSITION_VISUAL_IMPAIRED 0x0100 /**< stream for visual impaired audiences */ |
|
#define AV_DISPOSITION_CLEAN_EFFECTS 0x0200 /**< stream without voice */ |
|
/** |
|
* The stream is stored in the file as an attached picture/"cover art" (e.g. |
|
* APIC frame in ID3v2). The first (usually only) packet associated with it |
|
* will be returned among the first few packets read from the file unless |
|
* seeking takes place. It can also be accessed at any time in |
|
* AVStream.attached_pic. |
|
*/ |
|
#define AV_DISPOSITION_ATTACHED_PIC 0x0400 |
|
/** |
|
* The stream is sparse, and contains thumbnail images, often corresponding |
|
* to chapter markers. Only ever used with AV_DISPOSITION_ATTACHED_PIC. |
|
*/ |
|
#define AV_DISPOSITION_TIMED_THUMBNAILS 0x0800 |
|
|
|
typedef struct AVStreamInternal AVStreamInternal; |
|
|
|
/** |
|
* To specify text track kind (different from subtitles default). |
|
*/ |
|
#define AV_DISPOSITION_CAPTIONS 0x10000 |
|
#define AV_DISPOSITION_DESCRIPTIONS 0x20000 |
|
#define AV_DISPOSITION_METADATA 0x40000 |
|
#define AV_DISPOSITION_DEPENDENT 0x80000 ///< dependent audio stream (mix_type=0 in mpegts) |
|
#define AV_DISPOSITION_STILL_IMAGE 0x100000 ///< still images in video stream (still_picture_flag=1 in mpegts) |
|
|
|
/** |
|
* Options for behavior on timestamp wrap detection. |
|
*/ |
|
#define AV_PTS_WRAP_IGNORE 0 ///< ignore the wrap |
|
#define AV_PTS_WRAP_ADD_OFFSET 1 ///< add the format specific offset on wrap detection |
|
#define AV_PTS_WRAP_SUB_OFFSET -1 ///< subtract the format specific offset on wrap detection |
|
|
|
/** |
|
* Stream structure. |
|
* New fields can be added to the end with minor version bumps. |
|
* Removal, reordering and changes to existing fields require a major |
|
* version bump. |
|
* sizeof(AVStream) must not be used outside libav*. |
|
*/ |
|
typedef struct AVStream { |
|
int index; /**< stream index in AVFormatContext */ |
|
/** |
|
* Format-specific stream ID. |
|
* decoding: set by libavformat |
|
* encoding: set by the user, replaced by libavformat if left unset |
|
*/ |
|
int id; |
|
|
|
void *priv_data; |
|
|
|
/** |
|
* This is the fundamental unit of time (in seconds) in terms |
|
* of which frame timestamps are represented. |
|
* |
|
* decoding: set by libavformat |
|
* encoding: May be set by the caller before avformat_write_header() to |
|
* provide a hint to the muxer about the desired timebase. In |
|
* avformat_write_header(), the muxer will overwrite this field |
|
* with the timebase that will actually be used for the timestamps |
|
* written into the file (which may or may not be related to the |
|
* user-provided one, depending on the format). |
|
*/ |
|
AVRational time_base; |
|
|
|
/** |
|
* Decoding: pts of the first frame of the stream in presentation order, in stream time base. |
|
* Only set this if you are absolutely 100% sure that the value you set |
|
* it to really is the pts of the first frame. |
|
* This may be undefined (AV_NOPTS_VALUE). |
|
* @note The ASF header does NOT contain a correct start_time the ASF |
|
* demuxer must NOT set this. |
|
*/ |
|
int64_t start_time; |
|
|
|
/** |
|
* Decoding: duration of the stream, in stream time base. |
|
* If a source file does not specify a duration, but does specify |
|
* a bitrate, this value will be estimated from bitrate and file size. |
|
* |
|
* Encoding: May be set by the caller before avformat_write_header() to |
|
* provide a hint to the muxer about the estimated duration. |
|
*/ |
|
int64_t duration; |
|
|
|
int64_t nb_frames; ///< number of frames in this stream if known or 0 |
|
|
|
int disposition; /**< AV_DISPOSITION_* bit field */ |
|
|
|
enum AVDiscard discard; ///< Selects which packets can be discarded at will and do not need to be demuxed. |
|
|
|
/** |
|
* sample aspect ratio (0 if unknown) |
|
* - encoding: Set by user. |
|
* - decoding: Set by libavformat. |
|
*/ |
|
AVRational sample_aspect_ratio; |
|
|
|
AVDictionary *metadata; |
|
|
|
/** |
|
* Average framerate |
|
* |
|
* - demuxing: May be set by libavformat when creating the stream or in |
|
* avformat_find_stream_info(). |
|
* - muxing: May be set by the caller before avformat_write_header(). |
|
*/ |
|
AVRational avg_frame_rate; |
|
|
|
/** |
|
* For streams with AV_DISPOSITION_ATTACHED_PIC disposition, this packet |
|
* will contain the attached picture. |
|
* |
|
* decoding: set by libavformat, must not be modified by the caller. |
|
* encoding: unused |
|
*/ |
|
AVPacket attached_pic; |
|
|
|
/** |
|
* An array of side data that applies to the whole stream (i.e. the |
|
* container does not allow it to change between packets). |
|
* |
|
* There may be no overlap between the side data in this array and side data |
|
* in the packets. I.e. a given side data is either exported by the muxer |
|
* (demuxing) / set by the caller (muxing) in this array, then it never |
|
* appears in the packets, or the side data is exported / sent through |
|
* the packets (always in the first packet where the value becomes known or |
|
* changes), then it does not appear in this array. |
|
* |
|
* - demuxing: Set by libavformat when the stream is created. |
|
* - muxing: May be set by the caller before avformat_write_header(). |
|
* |
|
* Freed by libavformat in avformat_free_context(). |
|
* |
|
* @see av_format_inject_global_side_data() |
|
*/ |
|
AVPacketSideData *side_data; |
|
/** |
|
* The number of elements in the AVStream.side_data array. |
|
*/ |
|
int nb_side_data; |
|
|
|
/** |
|
* Flags indicating events happening on the stream, a combination of |
|
* AVSTREAM_EVENT_FLAG_*. |
|
* |
|
* - demuxing: may be set by the demuxer in avformat_open_input(), |
|
* avformat_find_stream_info() and av_read_frame(). Flags must be cleared |
|
* by the user once the event has been handled. |
|
* - muxing: may be set by the user after avformat_write_header(). to |
|
* indicate a user-triggered event. The muxer will clear the flags for |
|
* events it has handled in av_[interleaved]_write_frame(). |
|
*/ |
|
int event_flags; |
|
/** |
|
* - demuxing: the demuxer read new metadata from the file and updated |
|
* AVStream.metadata accordingly |
|
* - muxing: the user updated AVStream.metadata and wishes the muxer to write |
|
* it into the file |
|
*/ |
|
#define AVSTREAM_EVENT_FLAG_METADATA_UPDATED 0x0001 |
|
/** |
|
* - demuxing: new packets for this stream were read from the file. This |
|
* event is informational only and does not guarantee that new packets |
|
* for this stream will necessarily be returned from av_read_frame(). |
|
*/ |
|
#define AVSTREAM_EVENT_FLAG_NEW_PACKETS (1 << 1) |
|
|
|
/** |
|
* Real base framerate of the stream. |
|
* This is the lowest framerate with which all timestamps can be |
|
* represented accurately (it is the least common multiple of all |
|
* framerates in the stream). Note, this value is just a guess! |
|
* For example, if the time base is 1/90000 and all frames have either |
|
* approximately 3600 or 1800 timer ticks, then r_frame_rate will be 50/1. |
|
*/ |
|
AVRational r_frame_rate; |
|
|
|
/** |
|
* Codec parameters associated with this stream. Allocated and freed by |
|
* libavformat in avformat_new_stream() and avformat_free_context() |
|
* respectively. |
|
* |
|
* - demuxing: filled by libavformat on stream creation or in |
|
* avformat_find_stream_info() |
|
* - muxing: filled by the caller before avformat_write_header() |
|
*/ |
|
AVCodecParameters *codecpar; |
|
|
|
/***************************************************************** |
|
* All fields below this line are not part of the public API. They |
|
* may not be used outside of libavformat and can be changed and |
|
* removed at will. |
|
* Internal note: be aware that physically removing these fields |
|
* will break ABI. Replace removed fields with dummy fields, and |
|
* add new fields to AVStreamInternal. |
|
***************************************************************** |
|
*/ |
|
|
|
int pts_wrap_bits; /**< number of bits in pts (used for wrapping control) */ |
|
|
|
// Timestamp generation support: |
|
/** |
|
* Timestamp corresponding to the last dts sync point. |
|
* |
|
* Initialized when AVCodecParserContext.dts_sync_point >= 0 and |
|
* a DTS is received from the underlying container. Otherwise set to |
|
* AV_NOPTS_VALUE by default. |
|
*/ |
|
int64_t first_dts; |
|
int64_t cur_dts; |
|
int64_t last_IP_pts; |
|
int last_IP_duration; |
|
|
|
/** |
|
* Number of packets to buffer for codec probing |
|
*/ |
|
int probe_packets; |
|
|
|
/** |
|
* Number of frames that have been demuxed during avformat_find_stream_info() |
|
*/ |
|
int codec_info_nb_frames; |
|
|
|
/* av_read_frame() support */ |
|
enum AVStreamParseType need_parsing; |
|
struct AVCodecParserContext *parser; |
|
|
|
/** |
|
* Stream Identifier |
|
* This is the MPEG-TS stream identifier +1 |
|
* 0 means unknown |
|
*/ |
|
int stream_identifier; |
|
|
|
/** |
|
* An opaque field for libavformat internal usage. |
|
* Must not be accessed in any way by callers. |
|
*/ |
|
AVStreamInternal *internal; |
|
} AVStream; |
|
|
|
struct AVCodecParserContext *av_stream_get_parser(const AVStream *s); |
|
|
|
/** |
|
* Returns the pts of the last muxed packet + its duration |
|
* |
|
* the retuned value is undefined when used with a demuxer. |
|
*/ |
|
int64_t av_stream_get_end_pts(const AVStream *st); |
|
|
|
#define AV_PROGRAM_RUNNING 1 |
|
|
|
/** |
|
* New fields can be added to the end with minor version bumps. |
|
* Removal, reordering and changes to existing fields require a major |
|
* version bump. |
|
* sizeof(AVProgram) must not be used outside libav*. |
|
*/ |
|
typedef struct AVProgram { |
|
int id; |
|
int flags; |
|
enum AVDiscard discard; ///< selects which program to discard and which to feed to the caller |
|
unsigned int *stream_index; |
|
unsigned int nb_stream_indexes; |
|
AVDictionary *metadata; |
|
|
|
int program_num; |
|
int pmt_pid; |
|
int pcr_pid; |
|
int pmt_version; |
|
|
|
/***************************************************************** |
|
* All fields below this line are not part of the public API. They |
|
* may not be used outside of libavformat and can be changed and |
|
* removed at will. |
|
* New public fields should be added right above. |
|
***************************************************************** |
|
*/ |
|
int64_t start_time; |
|
int64_t end_time; |
|
|
|
int64_t pts_wrap_reference; ///< reference dts for wrap detection |
|
int pts_wrap_behavior; ///< behavior on wrap detection |
|
} AVProgram; |
|
|
|
#define AVFMTCTX_NOHEADER 0x0001 /**< signal that no header is present |
|
(streams are added dynamically) */ |
|
#define AVFMTCTX_UNSEEKABLE 0x0002 /**< signal that the stream is definitely |
|
not seekable, and attempts to call the |
|
seek function will fail. For some |
|
network protocols (e.g. HLS), this can |
|
change dynamically at runtime. */ |
|
|
|
typedef struct AVChapter { |
|
int64_t id; ///< unique ID to identify the chapter |
|
AVRational time_base; ///< time base in which the start/end timestamps are specified |
|
int64_t start, end; ///< chapter start/end time in time_base units |
|
AVDictionary *metadata; |
|
} AVChapter; |
|
|
|
|
|
/** |
|
* Callback used by devices to communicate with application. |
|
*/ |
|
typedef int (*av_format_control_message)(struct AVFormatContext *s, int type, |
|
void *data, size_t data_size); |
|
|
|
typedef int (*AVOpenCallback)(struct AVFormatContext *s, AVIOContext **pb, const char *url, int flags, |
|
const AVIOInterruptCB *int_cb, AVDictionary **options); |
|
|
|
/** |
|
* The duration of a video can be estimated through various ways, and this enum can be used |
|
* to know how the duration was estimated. |
|
*/ |
|
enum AVDurationEstimationMethod { |
|
AVFMT_DURATION_FROM_PTS, ///< Duration accurately estimated from PTSes |
|
AVFMT_DURATION_FROM_STREAM, ///< Duration estimated from a stream with a known duration |
|
AVFMT_DURATION_FROM_BITRATE ///< Duration estimated from bitrate (less accurate) |
|
}; |
|
|
|
typedef struct AVFormatInternal AVFormatInternal; |
|
|
|
/** |
|
* Format I/O context. |
|
* New fields can be added to the end with minor version bumps. |
|
* Removal, reordering and changes to existing fields require a major |
|
* version bump. |
|
* sizeof(AVFormatContext) must not be used outside libav*, use |
|
* avformat_alloc_context() to create an AVFormatContext. |
|
* |
|
* Fields can be accessed through AVOptions (av_opt*), |
|
* the name string used matches the associated command line parameter name and |
|
* can be found in libavformat/options_table.h. |
|
* The AVOption/command line parameter names differ in some cases from the C |
|
* structure field names for historic reasons or brevity. |
|
*/ |
|
typedef struct AVFormatContext { |
|
/** |
|
* A class for logging and @ref avoptions. Set by avformat_alloc_context(). |
|
* Exports (de)muxer private options if they exist. |
|
*/ |
|
const AVClass *av_class; |
|
|
|
/** |
|
* The input container format. |
|
* |
|
* Demuxing only, set by avformat_open_input(). |
|
*/ |
|
const struct AVInputFormat *iformat; |
|
|
|
/** |
|
* The output container format. |
|
* |
|
* Muxing only, must be set by the caller before avformat_write_header(). |
|
*/ |
|
const struct AVOutputFormat *oformat; |
|
|
|
/** |
|
* Format private data. This is an AVOptions-enabled struct |
|
* if and only if iformat/oformat.priv_class is not NULL. |
|
* |
|
* - muxing: set by avformat_write_header() |
|
* - demuxing: set by avformat_open_input() |
|
*/ |
|
void *priv_data; |
|
|
|
/** |
|
* I/O context. |
|
* |
|
* - demuxing: either set by the user before avformat_open_input() (then |
|
* the user must close it manually) or set by avformat_open_input(). |
|
* - muxing: set by the user before avformat_write_header(). The caller must |
|
* take care of closing / freeing the IO context. |
|
* |
|
* Do NOT set this field if AVFMT_NOFILE flag is set in |
|
* iformat/oformat.flags. In such a case, the (de)muxer will handle |
|
* I/O in some other way and this field will be NULL. |
|
*/ |
|
AVIOContext *pb; |
|
|
|
/* stream info */ |
|
/** |
|
* Flags signalling stream properties. A combination of AVFMTCTX_*. |
|
* Set by libavformat. |
|
*/ |
|
int ctx_flags; |
|
|
|
/** |
|
* Number of elements in AVFormatContext.streams. |
|
* |
|
* Set by avformat_new_stream(), must not be modified by any other code. |
|
*/ |
|
unsigned int nb_streams; |
|
/** |
|
* A list of all streams in the file. New streams are created with |
|
* avformat_new_stream(). |
|
* |
|
* - demuxing: streams are created by libavformat in avformat_open_input(). |
|
* If AVFMTCTX_NOHEADER is set in ctx_flags, then new streams may also |
|
* appear in av_read_frame(). |
|
* - muxing: streams are created by the user before avformat_write_header(). |
|
* |
|
* Freed by libavformat in avformat_free_context(). |
|
*/ |
|
AVStream **streams; |
|
|
|
/** |
|
* input or output URL. Unlike the old filename field, this field has no |
|
* length restriction. |
|
* |
|
* - demuxing: set by avformat_open_input(), initialized to an empty |
|
* string if url parameter was NULL in avformat_open_input(). |
|
* - muxing: may be set by the caller before calling avformat_write_header() |
|
* (or avformat_init_output() if that is called first) to a string |
|
* which is freeable by av_free(). Set to an empty string if it |
|
* was NULL in avformat_init_output(). |
|
* |
|
* Freed by libavformat in avformat_free_context(). |
|
*/ |
|
char *url; |
|
|
|
/** |
|
* Position of the first frame of the component, in |
|
* AV_TIME_BASE fractional seconds. NEVER set this value directly: |
|
* It is deduced from the AVStream values. |
|
* |
|
* Demuxing only, set by libavformat. |
|
*/ |
|
int64_t start_time; |
|
|
|
/** |
|
* Duration of the stream, in AV_TIME_BASE fractional |
|
* seconds. Only set this value if you know none of the individual stream |
|
* durations and also do not set any of them. This is deduced from the |
|
* AVStream values if not set. |
|
* |
|
* Demuxing only, set by libavformat. |
|
*/ |
|
int64_t duration; |
|
|
|
/** |
|
* Total stream bitrate in bit/s, 0 if not |
|
* available. Never set it directly if the file_size and the |
|
* duration are known as FFmpeg can compute it automatically. |
|
*/ |
|
int64_t bit_rate; |
|
|
|
unsigned int packet_size; |
|
int max_delay; |
|
|
|
/** |
|
* Flags modifying the (de)muxer behaviour. A combination of AVFMT_FLAG_*. |
|
* Set by the user before avformat_open_input() / avformat_write_header(). |
|
*/ |
|
int flags; |
|
#define AVFMT_FLAG_GENPTS 0x0001 ///< Generate missing pts even if it requires parsing future frames. |
|
#define AVFMT_FLAG_IGNIDX 0x0002 ///< Ignore index. |
|
#define AVFMT_FLAG_NONBLOCK 0x0004 ///< Do not block when reading packets from input. |
|
#define AVFMT_FLAG_IGNDTS 0x0008 ///< Ignore DTS on frames that contain both DTS & PTS |
|
#define AVFMT_FLAG_NOFILLIN 0x0010 ///< Do not infer any values from other values, just return what is stored in the container |
|
#define AVFMT_FLAG_NOPARSE 0x0020 ///< Do not use AVParsers, you also must set AVFMT_FLAG_NOFILLIN as the fillin code works on frames and no parsing -> no frames. Also seeking to frames can not work if parsing to find frame boundaries has been disabled |
|
#define AVFMT_FLAG_NOBUFFER 0x0040 ///< Do not buffer frames when possible |
|
#define AVFMT_FLAG_CUSTOM_IO 0x0080 ///< The caller has supplied a custom AVIOContext, don't avio_close() it. |
|
#define AVFMT_FLAG_DISCARD_CORRUPT 0x0100 ///< Discard frames marked corrupted |
|
#define AVFMT_FLAG_FLUSH_PACKETS 0x0200 ///< Flush the AVIOContext every packet. |
|
/** |
|
* When muxing, try to avoid writing any random/volatile data to the output. |
|
* This includes any random IDs, real-time timestamps/dates, muxer version, etc. |
|
* |
|
* This flag is mainly intended for testing. |
|
*/ |
|
#define AVFMT_FLAG_BITEXACT 0x0400 |
|
#define AVFMT_FLAG_SORT_DTS 0x10000 ///< try to interleave outputted packets by dts (using this flag can slow demuxing down) |
|
#if FF_API_LAVF_PRIV_OPT |
|
#define AVFMT_FLAG_PRIV_OPT 0x20000 ///< Enable use of private options by delaying codec open (deprecated, does nothing) |
|
#endif |
|
#define AVFMT_FLAG_FAST_SEEK 0x80000 ///< Enable fast, but inaccurate seeks for some formats |
|
#define AVFMT_FLAG_SHORTEST 0x100000 ///< Stop muxing when the shortest stream stops. |
|
#define AVFMT_FLAG_AUTO_BSF 0x200000 ///< Add bitstream filters as requested by the muxer |
|
|
|
/** |
|
* Maximum size of the data read from input for determining |
|
* the input container format. |
|
* Demuxing only, set by the caller before avformat_open_input(). |
|
*/ |
|
int64_t probesize; |
|
|
|
/** |
|
* Maximum duration (in AV_TIME_BASE units) of the data read |
|
* from input in avformat_find_stream_info(). |
|
* Demuxing only, set by the caller before avformat_find_stream_info(). |
|
* Can be set to 0 to let avformat choose using a heuristic. |
|
*/ |
|
int64_t max_analyze_duration; |
|
|
|
const uint8_t *key; |
|
int keylen; |
|
|
|
unsigned int nb_programs; |
|
AVProgram **programs; |
|
|
|
/** |
|
* Forced video codec_id. |
|
* Demuxing: Set by user. |
|
*/ |
|
enum AVCodecID video_codec_id; |
|
|
|
/** |
|
* Forced audio codec_id. |
|
* Demuxing: Set by user. |
|
*/ |
|
enum AVCodecID audio_codec_id; |
|
|
|
/** |
|
* Forced subtitle codec_id. |
|
* Demuxing: Set by user. |
|
*/ |
|
enum AVCodecID subtitle_codec_id; |
|
|
|
/** |
|
* Maximum amount of memory in bytes to use for the index of each stream. |
|
* If the index exceeds this size, entries will be discarded as |
|
* needed to maintain a smaller size. This can lead to slower or less |
|
* accurate seeking (depends on demuxer). |
|
* Demuxers for which a full in-memory index is mandatory will ignore |
|
* this. |
|
* - muxing: unused |
|
* - demuxing: set by user |
|
*/ |
|
unsigned int max_index_size; |
|
|
|
/** |
|
* Maximum amount of memory in bytes to use for buffering frames |
|
* obtained from realtime capture devices. |
|
*/ |
|
unsigned int max_picture_buffer; |
|
|
|
/** |
|
* Number of chapters in AVChapter array. |
|
* When muxing, chapters are normally written in the file header, |
|
* so nb_chapters should normally be initialized before write_header |
|
* is called. Some muxers (e.g. mov and mkv) can also write chapters |
|
* in the trailer. To write chapters in the trailer, nb_chapters |
|
* must be zero when write_header is called and non-zero when |
|
* write_trailer is called. |
|
* - muxing: set by user |
|
* - demuxing: set by libavformat |
|
*/ |
|
unsigned int nb_chapters; |
|
AVChapter **chapters; |
|
|
|
/** |
|
* Metadata that applies to the whole file. |
|
* |
|
* - demuxing: set by libavformat in avformat_open_input() |
|
* - muxing: may be set by the caller before avformat_write_header() |
|
* |
|
* Freed by libavformat in avformat_free_context(). |
|
*/ |
|
AVDictionary *metadata; |
|
|
|
/** |
|
* Start time of the stream in real world time, in microseconds |
|
* since the Unix epoch (00:00 1st January 1970). That is, pts=0 in the |
|
* stream was captured at this real world time. |
|
* - muxing: Set by the caller before avformat_write_header(). If set to |
|
* either 0 or AV_NOPTS_VALUE, then the current wall-time will |
|
* be used. |
|
* - demuxing: Set by libavformat. AV_NOPTS_VALUE if unknown. Note that |
|
* the value may become known after some number of frames |
|
* have been received. |
|
*/ |
|
int64_t start_time_realtime; |
|
|
|
/** |
|
* The number of frames used for determining the framerate in |
|
* avformat_find_stream_info(). |
|
* Demuxing only, set by the caller before avformat_find_stream_info(). |
|
*/ |
|
int fps_probe_size; |
|
|
|
/** |
|
* Error recognition; higher values will detect more errors but may |
|
* misdetect some more or less valid parts as errors. |
|
* Demuxing only, set by the caller before avformat_open_input(). |
|
*/ |
|
int error_recognition; |
|
|
|
/** |
|
* Custom interrupt callbacks for the I/O layer. |
|
* |
|
* demuxing: set by the user before avformat_open_input(). |
|
* muxing: set by the user before avformat_write_header() |
|
* (mainly useful for AVFMT_NOFILE formats). The callback |
|
* should also be passed to avio_open2() if it's used to |
|
* open the file. |
|
*/ |
|
AVIOInterruptCB interrupt_callback; |
|
|
|
/** |
|
* Flags to enable debugging. |
|
*/ |
|
int debug; |
|
#define FF_FDEBUG_TS 0x0001 |
|
|
|
/** |
|
* Maximum buffering duration for interleaving. |
|
* |
|
* To ensure all the streams are interleaved correctly, |
|
* av_interleaved_write_frame() will wait until it has at least one packet |
|
* for each stream before actually writing any packets to the output file. |
|
* When some streams are "sparse" (i.e. there are large gaps between |
|
* successive packets), this can result in excessive buffering. |
|
* |
|
* This field specifies the maximum difference between the timestamps of the |
|
* first and the last packet in the muxing queue, above which libavformat |
|
* will output a packet regardless of whether it has queued a packet for all |
|
* the streams. |
|
* |
|
* Muxing only, set by the caller before avformat_write_header(). |
|
*/ |
|
int64_t max_interleave_delta; |
|
|
|
/** |
|
* Allow non-standard and experimental extension |
|
* @see AVCodecContext.strict_std_compliance |
|
*/ |
|
int strict_std_compliance; |
|
|
|
/** |
|
* Flags indicating events happening on the file, a combination of |
|
* AVFMT_EVENT_FLAG_*. |
|
* |
|
* - demuxing: may be set by the demuxer in avformat_open_input(), |
|
* avformat_find_stream_info() and av_read_frame(). Flags must be cleared |
|
* by the user once the event has been handled. |
|
* - muxing: may be set by the user after avformat_write_header() to |
|
* indicate a user-triggered event. The muxer will clear the flags for |
|
* events it has handled in av_[interleaved]_write_frame(). |
|
*/ |
|
int event_flags; |
|
/** |
|
* - demuxing: the demuxer read new metadata from the file and updated |
|
* AVFormatContext.metadata accordingly |
|
* - muxing: the user updated AVFormatContext.metadata and wishes the muxer to |
|
* write it into the file |
|
*/ |
|
#define AVFMT_EVENT_FLAG_METADATA_UPDATED 0x0001 |
|
|
|
/** |
|
* Maximum number of packets to read while waiting for the first timestamp. |
|
* Decoding only. |
|
*/ |
|
int max_ts_probe; |
|
|
|
/** |
|
* Avoid negative timestamps during muxing. |
|
* Any value of the AVFMT_AVOID_NEG_TS_* constants. |
|
* Note, this only works when using av_interleaved_write_frame. (interleave_packet_per_dts is in use) |
|
* - muxing: Set by user |
|
* - demuxing: unused |
|
*/ |
|
int avoid_negative_ts; |
|
#define AVFMT_AVOID_NEG_TS_AUTO -1 ///< Enabled when required by target format |
|
#define AVFMT_AVOID_NEG_TS_MAKE_NON_NEGATIVE 1 ///< Shift timestamps so they are non negative |
|
#define AVFMT_AVOID_NEG_TS_MAKE_ZERO 2 ///< Shift timestamps so that they start at 0 |
|
|
|
/** |
|
* Transport stream id. |
|
* This will be moved into demuxer private options. Thus no API/ABI compatibility |
|
*/ |
|
int ts_id; |
|
|
|
/** |
|
* Audio preload in microseconds. |
|
* Note, not all formats support this and unpredictable things may happen if it is used when not supported. |
|
* - encoding: Set by user |
|
* - decoding: unused |
|
*/ |
|
int audio_preload; |
|
|
|
/** |
|
* Max chunk time in microseconds. |
|
* Note, not all formats support this and unpredictable things may happen if it is used when not supported. |
|
* - encoding: Set by user |
|
* - decoding: unused |
|
*/ |
|
int max_chunk_duration; |
|
|
|
/** |
|
* Max chunk size in bytes |
|
* Note, not all formats support this and unpredictable things may happen if it is used when not supported. |
|
* - encoding: Set by user |
|
* - decoding: unused |
|
*/ |
|
int max_chunk_size; |
|
|
|
/** |
|
* forces the use of wallclock timestamps as pts/dts of packets |
|
* This has undefined results in the presence of B frames. |
|
* - encoding: unused |
|
* - decoding: Set by user |
|
*/ |
|
int use_wallclock_as_timestamps; |
|
|
|
/** |
|
* avio flags, used to force AVIO_FLAG_DIRECT. |
|
* - encoding: unused |
|
* - decoding: Set by user |
|
*/ |
|
int avio_flags; |
|
|
|
/** |
|
* The duration field can be estimated through various ways, and this field can be used |
|
* to know how the duration was estimated. |
|
* - encoding: unused |
|
* - decoding: Read by user |
|
*/ |
|
enum AVDurationEstimationMethod duration_estimation_method; |
|
|
|
/** |
|
* Skip initial bytes when opening stream |
|
* - encoding: unused |
|
* - decoding: Set by user |
|
*/ |
|
int64_t skip_initial_bytes; |
|
|
|
/** |
|
* Correct single timestamp overflows |
|
* - encoding: unused |
|
* - decoding: Set by user |
|
*/ |
|
unsigned int correct_ts_overflow; |
|
|
|
/** |
|
* Force seeking to any (also non key) frames. |
|
* - encoding: unused |
|
* - decoding: Set by user |
|
*/ |
|
int seek2any; |
|
|
|
/** |
|
* Flush the I/O context after each packet. |
|
* - encoding: Set by user |
|
* - decoding: unused |
|
*/ |
|
int flush_packets; |
|
|
|
/** |
|
* format probing score. |
|
* The maximal score is AVPROBE_SCORE_MAX, its set when the demuxer probes |
|
* the format. |
|
* - encoding: unused |
|
* - decoding: set by avformat, read by user |
|
*/ |
|
int probe_score; |
|
|
|
/** |
|
* number of bytes to read maximally to identify format. |
|
* - encoding: unused |
|
* - decoding: set by user |
|
*/ |
|
int format_probesize; |
|
|
|
/** |
|
* ',' separated list of allowed decoders. |
|
* If NULL then all are allowed |
|
* - encoding: unused |
|
* - decoding: set by user |
|
*/ |
|
char *codec_whitelist; |
|
|
|
/** |
|
* ',' separated list of allowed demuxers. |
|
* If NULL then all are allowed |
|
* - encoding: unused |
|
* - decoding: set by user |
|
*/ |
|
char *format_whitelist; |
|
|
|
/** |
|
* An opaque field for libavformat internal usage. |
|
* Must not be accessed in any way by callers. |
|
*/ |
|
AVFormatInternal *internal; |
|
|
|
/** |
|
* IO repositioned flag. |
|
* This is set by avformat when the underlaying IO context read pointer |
|
* is repositioned, for example when doing byte based seeking. |
|
* Demuxers can use the flag to detect such changes. |
|
*/ |
|
int io_repositioned; |
|
|
|
/** |
|
* Forced video codec. |
|
* This allows forcing a specific decoder, even when there are multiple with |
|
* the same codec_id. |
|
* Demuxing: Set by user |
|
*/ |
|
const AVCodec *video_codec; |
|
|
|
/** |
|
* Forced audio codec. |
|
* This allows forcing a specific decoder, even when there are multiple with |
|
* the same codec_id. |
|
* Demuxing: Set by user |
|
*/ |
|
const AVCodec *audio_codec; |
|
|
|
/** |
|
* Forced subtitle codec. |
|
* This allows forcing a specific decoder, even when there are multiple with |
|
* the same codec_id. |
|
* Demuxing: Set by user |
|
*/ |
|
const AVCodec *subtitle_codec; |
|
|
|
/** |
|
* Forced data codec. |
|
* This allows forcing a specific decoder, even when there are multiple with |
|
* the same codec_id. |
|
* Demuxing: Set by user |
|
*/ |
|
const AVCodec *data_codec; |
|
|
|
/** |
|
* Number of bytes to be written as padding in a metadata header. |
|
* Demuxing: Unused. |
|
* Muxing: Set by user via av_format_set_metadata_header_padding. |
|
*/ |
|
int metadata_header_padding; |
|
|
|
/** |
|
* User data. |
|
* This is a place for some private data of the user. |
|
*/ |
|
void *opaque; |
|
|
|
/** |
|
* Callback used by devices to communicate with application. |
|
*/ |
|
av_format_control_message control_message_cb; |
|
|
|
/** |
|
* Output timestamp offset, in microseconds. |
|
* Muxing: set by user |
|
*/ |
|
int64_t output_ts_offset; |
|
|
|
/** |
|
* dump format separator. |
|
* can be ", " or "\n " or anything else |
|
* - muxing: Set by user. |
|
* - demuxing: Set by user. |
|
*/ |
|
uint8_t *dump_separator; |
|
|
|
/** |
|
* Forced Data codec_id. |
|
* Demuxing: Set by user. |
|
*/ |
|
enum AVCodecID data_codec_id; |
|
|
|
/** |
|
* ',' separated list of allowed protocols. |
|
* - encoding: unused |
|
* - decoding: set by user |
|
*/ |
|
char *protocol_whitelist; |
|
|
|
/** |
|
* A callback for opening new IO streams. |
|
* |
|
* Whenever a muxer or a demuxer needs to open an IO stream (typically from |
|
* avformat_open_input() for demuxers, but for certain formats can happen at |
|
* other times as well), it will call this callback to obtain an IO context. |
|
* |
|
* @param s the format context |
|
* @param pb on success, the newly opened IO context should be returned here |
|
* @param url the url to open |
|
* @param flags a combination of AVIO_FLAG_* |
|
* @param options a dictionary of additional options, with the same |
|
* semantics as in avio_open2() |
|
* @return 0 on success, a negative AVERROR code on failure |
|
* |
|
* @note Certain muxers and demuxers do nesting, i.e. they open one or more |
|
* additional internal format contexts. Thus the AVFormatContext pointer |
|
* passed to this callback may be different from the one facing the caller. |
|
* It will, however, have the same 'opaque' field. |
|
*/ |
|
int (*io_open)(struct AVFormatContext *s, AVIOContext **pb, const char *url, |
|
int flags, AVDictionary **options); |
|
|
|
/** |
|
* A callback for closing the streams opened with AVFormatContext.io_open(). |
|
*/ |
|
void (*io_close)(struct AVFormatContext *s, AVIOContext *pb); |
|
|
|
/** |
|
* ',' separated list of disallowed protocols. |
|
* - encoding: unused |
|
* - decoding: set by user |
|
*/ |
|
char *protocol_blacklist; |
|
|
|
/** |
|
* The maximum number of streams. |
|
* - encoding: unused |
|
* - decoding: set by user |
|
*/ |
|
int max_streams; |
|
|
|
/** |
|
* Skip duration calcuation in estimate_timings_from_pts. |
|
* - encoding: unused |
|
* - decoding: set by user |
|
*/ |
|
int skip_estimate_duration_from_pts; |
|
|
|
/** |
|
* Maximum number of packets that can be probed |
|
* - encoding: unused |
|
* - decoding: set by user |
|
*/ |
|
int max_probe_packets; |
|
} AVFormatContext; |
|
|
|
/** |
|
* This function will cause global side data to be injected in the next packet |
|
* of each stream as well as after any subsequent seek. |
|
*/ |
|
void av_format_inject_global_side_data(AVFormatContext *s); |
|
|
|
/** |
|
* Returns the method used to set ctx->duration. |
|
* |
|
* @return AVFMT_DURATION_FROM_PTS, AVFMT_DURATION_FROM_STREAM, or AVFMT_DURATION_FROM_BITRATE. |
|
*/ |
|
enum AVDurationEstimationMethod av_fmt_ctx_get_duration_estimation_method(const AVFormatContext* ctx); |
|
|
|
/** |
|
* @defgroup lavf_core Core functions |
|
* @ingroup libavf |
|
* |
|
* Functions for querying libavformat capabilities, allocating core structures, |
|
* etc. |
|
* @{ |
|
*/ |
|
|
|
/** |
|
* Return the LIBAVFORMAT_VERSION_INT constant. |
|
*/ |
|
unsigned avformat_version(void); |
|
|
|
/** |
|
* Return the libavformat build-time configuration. |
|
*/ |
|
const char *avformat_configuration(void); |
|
|
|
/** |
|
* Return the libavformat license. |
|
*/ |
|
const char *avformat_license(void); |
|
|
|
/** |
|
* Do global initialization of network libraries. This is optional, |
|
* and not recommended anymore. |
|
* |
|
* This functions only exists to work around thread-safety issues |
|
* with older GnuTLS or OpenSSL libraries. If libavformat is linked |
|
* to newer versions of those libraries, or if you do not use them, |
|
* calling this function is unnecessary. Otherwise, you need to call |
|
* this function before any other threads using them are started. |
|
* |
|
* This function will be deprecated once support for older GnuTLS and |
|
* OpenSSL libraries is removed, and this function has no purpose |
|
* anymore. |
|
*/ |
|
int avformat_network_init(void); |
|
|
|
/** |
|
* Undo the initialization done by avformat_network_init. Call it only |
|
* once for each time you called avformat_network_init. |
|
*/ |
|
int avformat_network_deinit(void); |
|
|
|
/** |
|
* Iterate over all registered muxers. |
|
* |
|
* @param opaque a pointer where libavformat will store the iteration state. Must |
|
* point to NULL to start the iteration. |
|
* |
|
* @return the next registered muxer or NULL when the iteration is |
|
* finished |
|
*/ |
|
const AVOutputFormat *av_muxer_iterate(void **opaque); |
|
|
|
/** |
|
* Iterate over all registered demuxers. |
|
* |
|
* @param opaque a pointer where libavformat will store the iteration state. Must |
|
* point to NULL to start the iteration. |
|
* |
|
* @return the next registered demuxer or NULL when the iteration is |
|
* finished |
|
*/ |
|
const AVInputFormat *av_demuxer_iterate(void **opaque); |
|
|
|
/** |
|
* Allocate an AVFormatContext. |
|
* avformat_free_context() can be used to free the context and everything |
|
* allocated by the framework within it. |
|
*/ |
|
AVFormatContext *avformat_alloc_context(void); |
|
|
|
/** |
|
* Free an AVFormatContext and all its streams. |
|
* @param s context to free |
|
*/ |
|
void avformat_free_context(AVFormatContext *s); |
|
|
|
/** |
|
* Get the AVClass for AVFormatContext. It can be used in combination with |
|
* AV_OPT_SEARCH_FAKE_OBJ for examining options. |
|
* |
|
* @see av_opt_find(). |
|
*/ |
|
const AVClass *avformat_get_class(void); |
|
|
|
/** |
|
* Add a new stream to a media file. |
|
* |
|
* When demuxing, it is called by the demuxer in read_header(). If the |
|
* flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also |
|
* be called in read_packet(). |
|
* |
|
* When muxing, should be called by the user before avformat_write_header(). |
|
* |
|
* User is required to call avformat_free_context() to clean up the allocation |
|
* by avformat_new_stream(). |
|
* |
|
* @param s media file handle |
|
* @param c unused, does nothing |
|
* |
|
* @return newly created stream or NULL on error. |
|
*/ |
|
AVStream *avformat_new_stream(AVFormatContext *s, const AVCodec *c); |
|
|
|
/** |
|
* Wrap an existing array as stream side data. |
|
* |
|
* @param st stream |
|
* @param type side information type |
|
* @param data the side data array. It must be allocated with the av_malloc() |
|
* family of functions. The ownership of the data is transferred to |
|
* st. |
|
* @param size side information size |
|
* @return zero on success, a negative AVERROR code on failure. On failure, |
|
* the stream is unchanged and the data remains owned by the caller. |
|
*/ |
|
int av_stream_add_side_data(AVStream *st, enum AVPacketSideDataType type, |
|
uint8_t *data, size_t size); |
|
|
|
/** |
|
* Allocate new information from stream. |
|
* |
|
* @param stream stream |
|
* @param type desired side information type |
|
* @param size side information size |
|
* @return pointer to fresh allocated data or NULL otherwise |
|
*/ |
|
uint8_t *av_stream_new_side_data(AVStream *stream, |
|
enum AVPacketSideDataType type, size_t size); |
|
/** |
|
* Get side information from stream. |
|
* |
|
* @param stream stream |
|
* @param type desired side information type |
|
* @param size If supplied, *size will be set to the size of the side data |
|
* or to zero if the desired side data is not present. |
|
* @return pointer to data if present or NULL otherwise |
|
*/ |
|
uint8_t *av_stream_get_side_data(const AVStream *stream, |
|
enum AVPacketSideDataType type, size_t *size); |
|
|
|
AVProgram *av_new_program(AVFormatContext *s, int id); |
|
|
|
/** |
|
* @} |
|
*/ |
|
|
|
|
|
/** |
|
* Allocate an AVFormatContext for an output format. |
|
* avformat_free_context() can be used to free the context and |
|
* everything allocated by the framework within it. |
|
* |
|
* @param *ctx is set to the created format context, or to NULL in |
|
* case of failure |
|
* @param oformat format to use for allocating the context, if NULL |
|
* format_name and filename are used instead |
|
* @param format_name the name of output format to use for allocating the |
|
* context, if NULL filename is used instead |
|
* @param filename the name of the filename to use for allocating the |
|
* context, may be NULL |
|
* @return >= 0 in case of success, a negative AVERROR code in case of |
|
* failure |
|
*/ |
|
int avformat_alloc_output_context2(AVFormatContext **ctx, const AVOutputFormat *oformat, |
|
const char *format_name, const char *filename); |
|
|
|
/** |
|
* @addtogroup lavf_decoding |
|
* @{ |
|
*/ |
|
|
|
/** |
|
* Find AVInputFormat based on the short name of the input format. |
|
*/ |
|
const AVInputFormat *av_find_input_format(const char *short_name); |
|
|
|
/** |
|
* Guess the file format. |
|
* |
|
* @param pd data to be probed |
|
* @param is_opened Whether the file is already opened; determines whether |
|
* demuxers with or without AVFMT_NOFILE are probed. |
|
*/ |
|
const AVInputFormat *av_probe_input_format(const AVProbeData *pd, int is_opened); |
|
|
|
/** |
|
* Guess the file format. |
|
* |
|
* @param pd data to be probed |
|
* @param is_opened Whether the file is already opened; determines whether |
|
* demuxers with or without AVFMT_NOFILE are probed. |
|
* @param score_max A probe score larger that this is required to accept a |
|
* detection, the variable is set to the actual detection |
|
* score afterwards. |
|
* If the score is <= AVPROBE_SCORE_MAX / 4 it is recommended |
|
* to retry with a larger probe buffer. |
|
*/ |
|
const AVInputFormat *av_probe_input_format2(const AVProbeData *pd, |
|
int is_opened, int *score_max); |
|
|
|
/** |
|
* Guess the file format. |
|
* |
|
* @param is_opened Whether the file is already opened; determines whether |
|
* demuxers with or without AVFMT_NOFILE are probed. |
|
* @param score_ret The score of the best detection. |
|
*/ |
|
const AVInputFormat *av_probe_input_format3(const AVProbeData *pd, |
|
int is_opened, int *score_ret); |
|
|
|
/** |
|
* Probe a bytestream to determine the input format. Each time a probe returns |
|
* with a score that is too low, the probe buffer size is increased and another |
|
* attempt is made. When the maximum probe size is reached, the input format |
|
* with the highest score is returned. |
|
* |
|
* @param pb the bytestream to probe |
|
* @param fmt the input format is put here |
|
* @param url the url of the stream |
|
* @param logctx the log context |
|
* @param offset the offset within the bytestream to probe from |
|
* @param max_probe_size the maximum probe buffer size (zero for default) |
|
* @return the score in case of success, a negative value corresponding to an |
|
* the maximal score is AVPROBE_SCORE_MAX |
|
* AVERROR code otherwise |
|
*/ |
|
int av_probe_input_buffer2(AVIOContext *pb, const AVInputFormat **fmt, |
|
const char *url, void *logctx, |
|
unsigned int offset, unsigned int max_probe_size); |
|
|
|
/** |
|
* Like av_probe_input_buffer2() but returns 0 on success |
|
*/ |
|
int av_probe_input_buffer(AVIOContext *pb, const AVInputFormat **fmt, |
|
const char *url, void *logctx, |
|
unsigned int offset, unsigned int max_probe_size); |
|
|
|
/** |
|
* Open an input stream and read the header. The codecs are not opened. |
|
* The stream must be closed with avformat_close_input(). |
|
* |
|
* @param ps Pointer to user-supplied AVFormatContext (allocated by avformat_alloc_context). |
|
* May be a pointer to NULL, in which case an AVFormatContext is allocated by this |
|
* function and written into ps. |
|
* Note that a user-supplied AVFormatContext will be freed on failure. |
|
* @param url URL of the stream to open. |
|
* @param fmt If non-NULL, this parameter forces a specific input format. |
|
* Otherwise the format is autodetected. |
|
* @param options A dictionary filled with AVFormatContext and demuxer-private options. |
|
* On return this parameter will be destroyed and replaced with a dict containing |
|
* options that were not found. May be NULL. |
|
* |
|
* @return 0 on success, a negative AVERROR on failure. |
|
* |
|
* @note If you want to use custom IO, preallocate the format context and set its pb field. |
|
*/ |
|
int avformat_open_input(AVFormatContext **ps, const char *url, |
|
const AVInputFormat *fmt, AVDictionary **options); |
|
|
|
/** |
|
* Read packets of a media file to get stream information. This |
|
* is useful for file formats with no headers such as MPEG. This |
|
* function also computes the real framerate in case of MPEG-2 repeat |
|
* frame mode. |
|
* The logical file position is not changed by this function; |
|
* examined packets may be buffered for later processing. |
|
* |
|
* @param ic media file handle |
|
* @param options If non-NULL, an ic.nb_streams long array of pointers to |
|
* dictionaries, where i-th member contains options for |
|
* codec corresponding to i-th stream. |
|
* On return each dictionary will be filled with options that were not found. |
|
* @return >=0 if OK, AVERROR_xxx on error |
|
* |
|
* @note this function isn't guaranteed to open all the codecs, so |
|
* options being non-empty at return is a perfectly normal behavior. |
|
* |
|
* @todo Let the user decide somehow what information is needed so that |
|
* we do not waste time getting stuff the user does not need. |
|
*/ |
|
int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options); |
|
|
|
/** |
|
* Find the programs which belong to a given stream. |
|
* |
|
* @param ic media file handle |
|
* @param last the last found program, the search will start after this |
|
* program, or from the beginning if it is NULL |
|
* @param s stream index |
|
* @return the next program which belongs to s, NULL if no program is found or |
|
* the last program is not among the programs of ic. |
|
*/ |
|
AVProgram *av_find_program_from_stream(AVFormatContext *ic, AVProgram *last, int s); |
|
|
|
void av_program_add_stream_index(AVFormatContext *ac, int progid, unsigned int idx); |
|
|
|
/** |
|
* Find the "best" stream in the file. |
|
* The best stream is determined according to various heuristics as the most |
|
* likely to be what the user expects. |
|
* If the decoder parameter is non-NULL, av_find_best_stream will find the |
|
* default decoder for the stream's codec; streams for which no decoder can |
|
* be found are ignored. |
|
* |
|
* @param ic media file handle |
|
* @param type stream type: video, audio, subtitles, etc. |
|
* @param wanted_stream_nb user-requested stream number, |
|
* or -1 for automatic selection |
|
* @param related_stream try to find a stream related (eg. in the same |
|
* program) to this one, or -1 if none |
|
* @param decoder_ret if non-NULL, returns the decoder for the |
|
* selected stream |
|
* @param flags flags; none are currently defined |
|
* @return the non-negative stream number in case of success, |
|
* AVERROR_STREAM_NOT_FOUND if no stream with the requested type |
|
* could be found, |
|
* AVERROR_DECODER_NOT_FOUND if streams were found but no decoder |
|
* @note If av_find_best_stream returns successfully and decoder_ret is not |
|
* NULL, then *decoder_ret is guaranteed to be set to a valid AVCodec. |
|
*/ |
|
int av_find_best_stream(AVFormatContext *ic, |
|
enum AVMediaType type, |
|
int wanted_stream_nb, |
|
int related_stream, |
|
const AVCodec **decoder_ret, |
|
int flags); |
|
|
|
/** |
|
* Return the next frame of a stream. |
|
* This function returns what is stored in the file, and does not validate |
|
* that what is there are valid frames for the decoder. It will split what is |
|
* stored in the file into frames and return one for each call. It will not |
|
* omit invalid data between valid frames so as to give the decoder the maximum |
|
* information possible for decoding. |
|
* |
|
* On success, the returned packet is reference-counted (pkt->buf is set) and |
|
* valid indefinitely. The packet must be freed with av_packet_unref() when |
|
* it is no longer needed. For video, the packet contains exactly one frame. |
|
* For audio, it contains an integer number of frames if each frame has |
|
* a known fixed size (e.g. PCM or ADPCM data). If the audio frames have |
|
* a variable size (e.g. MPEG audio), then it contains one frame. |
|
* |
|
* pkt->pts, pkt->dts and pkt->duration are always set to correct |
|
* values in AVStream.time_base units (and guessed if the format cannot |
|
* provide them). pkt->pts can be AV_NOPTS_VALUE if the video format |
|
* has B-frames, so it is better to rely on pkt->dts if you do not |
|
* decompress the payload. |
|
* |
|
* @return 0 if OK, < 0 on error or end of file. On error, pkt will be blank |
|
* (as if it came from av_packet_alloc()). |
|
* |
|
* @note pkt will be initialized, so it may be uninitialized, but it must not |
|
* contain data that needs to be freed. |
|
*/ |
|
int av_read_frame(AVFormatContext *s, AVPacket *pkt); |
|
|
|
/** |
|
* Seek to the keyframe at timestamp. |
|
* 'timestamp' in 'stream_index'. |
|
* |
|
* @param s media file handle |
|
* @param stream_index If stream_index is (-1), a default |
|
* stream is selected, and timestamp is automatically converted |
|
* from AV_TIME_BASE units to the stream specific time_base. |
|
* @param timestamp Timestamp in AVStream.time_base units |
|
* or, if no stream is specified, in AV_TIME_BASE units. |
|
* @param flags flags which select direction and seeking mode |
|
* @return >= 0 on success |
|
*/ |
|
int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp, |
|
int flags); |
|
|
|
/** |
|
* Seek to timestamp ts. |
|
* Seeking will be done so that the point from which all active streams |
|
* can be presented successfully will be closest to ts and within min/max_ts. |
|
* Active streams are all streams that have AVStream.discard < AVDISCARD_ALL. |
|
* |
|
* If flags contain AVSEEK_FLAG_BYTE, then all timestamps are in bytes and |
|
* are the file position (this may not be supported by all demuxers). |
|
* If flags contain AVSEEK_FLAG_FRAME, then all timestamps are in frames |
|
* in the stream with stream_index (this may not be supported by all demuxers). |
|
* Otherwise all timestamps are in units of the stream selected by stream_index |
|
* or if stream_index is -1, in AV_TIME_BASE units. |
|
* If flags contain AVSEEK_FLAG_ANY, then non-keyframes are treated as |
|
* keyframes (this may not be supported by all demuxers). |
|
* If flags contain AVSEEK_FLAG_BACKWARD, it is ignored. |
|
* |
|
* @param s media file handle |
|
* @param stream_index index of the stream which is used as time base reference |
|
* @param min_ts smallest acceptable timestamp |
|
* @param ts target timestamp |
|
* @param max_ts largest acceptable timestamp |
|
* @param flags flags |
|
* @return >=0 on success, error code otherwise |
|
* |
|
* @note This is part of the new seek API which is still under construction. |
|
*/ |
|
int avformat_seek_file(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags); |
|
|
|
/** |
|
* Discard all internally buffered data. This can be useful when dealing with |
|
* discontinuities in the byte stream. Generally works only with formats that |
|
* can resync. This includes headerless formats like MPEG-TS/TS but should also |
|
* work with NUT, Ogg and in a limited way AVI for example. |
|
* |
|
* The set of streams, the detected duration, stream parameters and codecs do |
|
* not change when calling this function. If you want a complete reset, it's |
|
* better to open a new AVFormatContext. |
|
* |
|
* This does not flush the AVIOContext (s->pb). If necessary, call |
|
* avio_flush(s->pb) before calling this function. |
|
* |
|
* @param s media file handle |
|
* @return >=0 on success, error code otherwise |
|
*/ |
|
int avformat_flush(AVFormatContext *s); |
|
|
|
/** |
|
* Start playing a network-based stream (e.g. RTSP stream) at the |
|
* current position. |
|
*/ |
|
int av_read_play(AVFormatContext *s); |
|
|
|
/** |
|
* Pause a network-based stream (e.g. RTSP stream). |
|
* |
|
* Use av_read_play() to resume it. |
|
*/ |
|
int av_read_pause(AVFormatContext *s); |
|
|
|
/** |
|
* Close an opened input AVFormatContext. Free it and all its contents |
|
* and set *s to NULL. |
|
*/ |
|
void avformat_close_input(AVFormatContext **s); |
|
/** |
|
* @} |
|
*/ |
|
|
|
#define AVSEEK_FLAG_BACKWARD 1 ///< seek backward |
|
#define AVSEEK_FLAG_BYTE 2 ///< seeking based on position in bytes |
|
#define AVSEEK_FLAG_ANY 4 ///< seek to any frame, even non-keyframes |
|
#define AVSEEK_FLAG_FRAME 8 ///< seeking based on frame number |
|
|
|
/** |
|
* @addtogroup lavf_encoding |
|
* @{ |
|
*/ |
|
|
|
#define AVSTREAM_INIT_IN_WRITE_HEADER 0 ///< stream parameters initialized in avformat_write_header |
|
#define AVSTREAM_INIT_IN_INIT_OUTPUT 1 ///< stream parameters initialized in avformat_init_output |
|
|
|
/** |
|
* Allocate the stream private data and write the stream header to |
|
* an output media file. |
|
* |
|
* @param s Media file handle, must be allocated with avformat_alloc_context(). |
|
* Its oformat field must be set to the desired output format; |
|
* Its pb field must be set to an already opened AVIOContext. |
|
* @param options An AVDictionary filled with AVFormatContext and muxer-private options. |
|
* On return this parameter will be destroyed and replaced with a dict containing |
|
* options that were not found. May be NULL. |
|
* |
|
* @return AVSTREAM_INIT_IN_WRITE_HEADER on success if the codec had not already been fully initialized in avformat_init, |
|
* AVSTREAM_INIT_IN_INIT_OUTPUT on success if the codec had already been fully initialized in avformat_init, |
|
* negative AVERROR on failure. |
|
* |
|
* @see av_opt_find, av_dict_set, avio_open, av_oformat_next, avformat_init_output. |
|
*/ |
|
av_warn_unused_result |
|
int avformat_write_header(AVFormatContext *s, AVDictionary **options); |
|
|
|
/** |
|
* Allocate the stream private data and initialize the codec, but do not write the header. |
|
* May optionally be used before avformat_write_header to initialize stream parameters |
|
* before actually writing the header. |
|
* If using this function, do not pass the same options to avformat_write_header. |
|
* |
|
* @param s Media file handle, must be allocated with avformat_alloc_context(). |
|
* Its oformat field must be set to the desired output format; |
|
* Its pb field must be set to an already opened AVIOContext. |
|
* @param options An AVDictionary filled with AVFormatContext and muxer-private options. |
|
* On return this parameter will be destroyed and replaced with a dict containing |
|
* options that were not found. May be NULL. |
|
* |
|
* @return AVSTREAM_INIT_IN_WRITE_HEADER on success if the codec requires avformat_write_header to fully initialize, |
|
* AVSTREAM_INIT_IN_INIT_OUTPUT on success if the codec has been fully initialized, |
|
* negative AVERROR on failure. |
|
* |
|
* @see av_opt_find, av_dict_set, avio_open, av_oformat_next, avformat_write_header. |
|
*/ |
|
av_warn_unused_result |
|
int avformat_init_output(AVFormatContext *s, AVDictionary **options); |
|
|
|
/** |
|
* Write a packet to an output media file. |
|
* |
|
* This function passes the packet directly to the muxer, without any buffering |
|
* or reordering. The caller is responsible for correctly interleaving the |
|
* packets if the format requires it. Callers that want libavformat to handle |
|
* the interleaving should call av_interleaved_write_frame() instead of this |
|
* function. |
|
* |
|
* @param s media file handle |
|
* @param pkt The packet containing the data to be written. Note that unlike |
|
* av_interleaved_write_frame(), this function does not take |
|
* ownership of the packet passed to it (though some muxers may make |
|
* an internal reference to the input packet). |
|
* <br> |
|
* This parameter can be NULL (at any time, not just at the end), in |
|
* order to immediately flush data buffered within the muxer, for |
|
* muxers that buffer up data internally before writing it to the |
|
* output. |
|
* <br> |
|
* Packet's @ref AVPacket.stream_index "stream_index" field must be |
|
* set to the index of the corresponding stream in @ref |
|
* AVFormatContext.streams "s->streams". |
|
* <br> |
|
* The timestamps (@ref AVPacket.pts "pts", @ref AVPacket.dts "dts") |
|
* must be set to correct values in the stream's timebase (unless the |
|
* output format is flagged with the AVFMT_NOTIMESTAMPS flag, then |
|
* they can be set to AV_NOPTS_VALUE). |
|
* The dts for subsequent packets passed to this function must be strictly |
|
* increasing when compared in their respective timebases (unless the |
|
* output format is flagged with the AVFMT_TS_NONSTRICT, then they |
|
* merely have to be nondecreasing). @ref AVPacket.duration |
|
* "duration") should also be set if known. |
|
* @return < 0 on error, = 0 if OK, 1 if flushed and there is no more data to flush |
|
* |
|
* @see av_interleaved_write_frame() |
|
*/ |
|
int av_write_frame(AVFormatContext *s, AVPacket *pkt); |
|
|
|
/** |
|
* Write a packet to an output media file ensuring correct interleaving. |
|
* |
|
* This function will buffer the packets internally as needed to make sure the |
|
* packets in the output file are properly interleaved in the order of |
|
* increasing dts. Callers doing their own interleaving should call |
|
* av_write_frame() instead of this function. |
|
* |
|
* Using this function instead of av_write_frame() can give muxers advance |
|
* knowledge of future packets, improving e.g. the behaviour of the mp4 |
|
* muxer for VFR content in fragmenting mode. |
|
* |
|
* @param s media file handle |
|
* @param pkt The packet containing the data to be written. |
|
* <br> |
|
* If the packet is reference-counted, this function will take |
|
* ownership of this reference and unreference it later when it sees |
|
* fit. |
|
* The caller must not access the data through this reference after |
|
* this function returns. If the packet is not reference-counted, |
|
* libavformat will make a copy. |
|
* <br> |
|
* This parameter can be NULL (at any time, not just at the end), to |
|
* flush the interleaving queues. |
|
* <br> |
|
* Packet's @ref AVPacket.stream_index "stream_index" field must be |
|
* set to the index of the corresponding stream in @ref |
|
* AVFormatContext.streams "s->streams". |
|
* <br> |
|
* The timestamps (@ref AVPacket.pts "pts", @ref AVPacket.dts "dts") |
|
* must be set to correct values in the stream's timebase (unless the |
|
* output format is flagged with the AVFMT_NOTIMESTAMPS flag, then |
|
* they can be set to AV_NOPTS_VALUE). |
|
* The dts for subsequent packets in one stream must be strictly |
|
* increasing (unless the output format is flagged with the |
|
* AVFMT_TS_NONSTRICT, then they merely have to be nondecreasing). |
|
* @ref AVPacket.duration "duration") should also be set if known. |
|
* |
|
* @return 0 on success, a negative AVERROR on error. Libavformat will always |
|
* take care of freeing the packet, even if this function fails. |
|
* |
|
* @see av_write_frame(), AVFormatContext.max_interleave_delta |
|
*/ |
|
int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt); |
|
|
|
/** |
|
* Write an uncoded frame to an output media file. |
|
* |
|
* The frame must be correctly interleaved according to the container |
|
* specification; if not, av_interleaved_write_uncoded_frame() must be used. |
|
* |
|
* See av_interleaved_write_uncoded_frame() for details. |
|
*/ |
|
int av_write_uncoded_frame(AVFormatContext *s, int stream_index, |
|
AVFrame *frame); |
|
|
|
/** |
|
* Write an uncoded frame to an output media file. |
|
* |
|
* If the muxer supports it, this function makes it possible to write an AVFrame |
|
* structure directly, without encoding it into a packet. |
|
* It is mostly useful for devices and similar special muxers that use raw |
|
* video or PCM data and will not serialize it into a byte stream. |
|
* |
|
* To test whether it is possible to use it with a given muxer and stream, |
|
* use av_write_uncoded_frame_query(). |
|
* |
|
* The caller gives up ownership of the frame and must not access it |
|
* afterwards. |
|
* |
|
* @return >=0 for success, a negative code on error |
|
*/ |
|
int av_interleaved_write_uncoded_frame(AVFormatContext *s, int stream_index, |
|
AVFrame *frame); |
|
|
|
/** |
|
* Test whether a muxer supports uncoded frame. |
|
* |
|
* @return >=0 if an uncoded frame can be written to that muxer and stream, |
|
* <0 if not |
|
*/ |
|
int av_write_uncoded_frame_query(AVFormatContext *s, int stream_index); |
|
|
|
/** |
|
* Write the stream trailer to an output media file and free the |
|
* file private data. |
|
* |
|
* May only be called after a successful call to avformat_write_header. |
|
* |
|
* @param s media file handle |
|
* @return 0 if OK, AVERROR_xxx on error |
|
*/ |
|
int av_write_trailer(AVFormatContext *s); |
|
|
|
/** |
|
* Return the output format in the list of registered output formats |
|
* which best matches the provided parameters, or return NULL if |
|
* there is no match. |
|
* |
|
* @param short_name if non-NULL checks if short_name matches with the |
|
* names of the registered formats |
|
* @param filename if non-NULL checks if filename terminates with the |
|
* extensions of the registered formats |
|
* @param mime_type if non-NULL checks if mime_type matches with the |
|
* MIME type of the registered formats |
|
*/ |
|
const AVOutputFormat *av_guess_format(const char *short_name, |
|
const char *filename, |
|
const char *mime_type); |
|
|
|
/** |
|
* Guess the codec ID based upon muxer and filename. |
|
*/ |
|
enum AVCodecID av_guess_codec(const AVOutputFormat *fmt, const char *short_name, |
|
const char *filename, const char *mime_type, |
|
enum AVMediaType type); |
|
|
|
/** |
|
* Get timing information for the data currently output. |
|
* The exact meaning of "currently output" depends on the format. |
|
* It is mostly relevant for devices that have an internal buffer and/or |
|
* work in real time. |
|
* @param s media file handle |
|
* @param stream stream in the media file |
|
* @param[out] dts DTS of the last packet output for the stream, in stream |
|
* time_base units |
|
* @param[out] wall absolute time when that packet whas output, |
|
* in microsecond |
|
* @return 0 if OK, AVERROR(ENOSYS) if the format does not support it |
|
* Note: some formats or devices may not allow to measure dts and wall |
|
* atomically. |
|
*/ |
|
int av_get_output_timestamp(struct AVFormatContext *s, int stream, |
|
int64_t *dts, int64_t *wall); |
|
|
|
|
|
/** |
|
* @} |
|
*/ |
|
|
|
|
|
/** |
|
* @defgroup lavf_misc Utility functions |
|
* @ingroup libavf |
|
* @{ |
|
* |
|
* Miscellaneous utility functions related to both muxing and demuxing |
|
* (or neither). |
|
*/ |
|
|
|
/** |
|
* Send a nice hexadecimal dump of a buffer to the specified file stream. |
|
* |
|
* @param f The file stream pointer where the dump should be sent to. |
|
* @param buf buffer |
|
* @param size buffer size |
|
* |
|
* @see av_hex_dump_log, av_pkt_dump2, av_pkt_dump_log2 |
|
*/ |
|
void av_hex_dump(FILE *f, const uint8_t *buf, int size); |
|
|
|
/** |
|
* Send a nice hexadecimal dump of a buffer to the log. |
|
* |
|
* @param avcl A pointer to an arbitrary struct of which the first field is a |
|
* pointer to an AVClass struct. |
|
* @param level The importance level of the message, lower values signifying |
|
* higher importance. |
|
* @param buf buffer |
|
* @param size buffer size |
|
* |
|
* @see av_hex_dump, av_pkt_dump2, av_pkt_dump_log2 |
|
*/ |
|
void av_hex_dump_log(void *avcl, int level, const uint8_t *buf, int size); |
|
|
|
/** |
|
* Send a nice dump of a packet to the specified file stream. |
|
* |
|
* @param f The file stream pointer where the dump should be sent to. |
|
* @param pkt packet to dump |
|
* @param dump_payload True if the payload must be displayed, too. |
|
* @param st AVStream that the packet belongs to |
|
*/ |
|
void av_pkt_dump2(FILE *f, const AVPacket *pkt, int dump_payload, const AVStream *st); |
|
|
|
|
|
/** |
|
* Send a nice dump of a packet to the log. |
|
* |
|
* @param avcl A pointer to an arbitrary struct of which the first field is a |
|
* pointer to an AVClass struct. |
|
* @param level The importance level of the message, lower values signifying |
|
* higher importance. |
|
* @param pkt packet to dump |
|
* @param dump_payload True if the payload must be displayed, too. |
|
* @param st AVStream that the packet belongs to |
|
*/ |
|
void av_pkt_dump_log2(void *avcl, int level, const AVPacket *pkt, int dump_payload, |
|
const AVStream *st); |
|
|
|
/** |
|
* Get the AVCodecID for the given codec tag tag. |
|
* If no codec id is found returns AV_CODEC_ID_NONE. |
|
* |
|
* @param tags list of supported codec_id-codec_tag pairs, as stored |
|
* in AVInputFormat.codec_tag and AVOutputFormat.codec_tag |
|
* @param tag codec tag to match to a codec ID |
|
*/ |
|
enum AVCodecID av_codec_get_id(const struct AVCodecTag * const *tags, unsigned int tag); |
|
|
|
/** |
|
* Get the codec tag for the given codec id id. |
|
* If no codec tag is found returns 0. |
|
* |
|
* @param tags list of supported codec_id-codec_tag pairs, as stored |
|
* in AVInputFormat.codec_tag and AVOutputFormat.codec_tag |
|
* @param id codec ID to match to a codec tag |
|
*/ |
|
unsigned int av_codec_get_tag(const struct AVCodecTag * const *tags, enum AVCodecID id); |
|
|
|
/** |
|
* Get the codec tag for the given codec id. |
|
* |
|
* @param tags list of supported codec_id - codec_tag pairs, as stored |
|
* in AVInputFormat.codec_tag and AVOutputFormat.codec_tag |
|
* @param id codec id that should be searched for in the list |
|
* @param tag A pointer to the found tag |
|
* @return 0 if id was not found in tags, > 0 if it was found |
|
*/ |
|
int av_codec_get_tag2(const struct AVCodecTag * const *tags, enum AVCodecID id, |
|
unsigned int *tag); |
|
|
|
int av_find_default_stream_index(AVFormatContext *s); |
|
|
|
/** |
|
* Get the index for a specific timestamp. |
|
* |
|
* @param st stream that the timestamp belongs to |
|
* @param timestamp timestamp to retrieve the index for |
|
* @param flags if AVSEEK_FLAG_BACKWARD then the returned index will correspond |
|
* to the timestamp which is <= the requested one, if backward |
|
* is 0, then it will be >= |
|
* if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise |
|
* @return < 0 if no such timestamp could be found |
|
*/ |
|
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags); |
|
|
|
/** |
|
* Get the index entry count for the given AVStream. |
|
* |
|
* @param st stream |
|
* @return the number of index entries in the stream |
|
*/ |
|
int avformat_index_get_entries_count(const AVStream *st); |
|
|
|
/** |
|
* Get the AVIndexEntry corresponding to the given index. |
|
* |
|
* @param st Stream containing the requested AVIndexEntry. |
|
* @param idx The desired index. |
|
* @return A pointer to the requested AVIndexEntry if it exists, NULL otherwise. |
|
* |
|
* @note The pointer returned by this function is only guaranteed to be valid |
|
* until any function that could alter the stream or the AVFormatContext |
|
* that contains it is called. |
|
*/ |
|
const AVIndexEntry *avformat_index_get_entry(const AVStream *st, int idx); |
|
|
|
/** |
|
* Get the AVIndexEntry corresponding to the given timestamp. |
|
* |
|
* @param st Stream containing the requested AVIndexEntry. |
|
* @param timestamp Timestamp to retrieve the index entry for. |
|
* @param flags If AVSEEK_FLAG_BACKWARD then the returned entry will correspond |
|
* to the timestamp which is <= the requested one, if backward |
|
* is 0, then it will be >= |
|
* if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise. |
|
* @return A pointer to the requested AVIndexEntry if it exists, NULL otherwise. |
|
* |
|
* @note The pointer returned by this function is only guaranteed to be valid |
|
* until any function that could alter the stream or the AVFormatContext |
|
* that contains it is called. |
|
*/ |
|
const AVIndexEntry *avformat_index_get_entry_from_timestamp(const AVStream *st, |
|
int64_t wanted_timestamp, |
|
int flags); |
|
/** |
|
* Add an index entry into a sorted list. Update the entry if the list |
|
* already contains it. |
|
* |
|
* @param timestamp timestamp in the time base of the given stream |
|
*/ |
|
int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp, |
|
int size, int distance, int flags); |
|
|
|
|
|
/** |
|
* Split a URL string into components. |
|
* |
|
* The pointers to buffers for storing individual components may be null, |
|
* in order to ignore that component. Buffers for components not found are |
|
* set to empty strings. If the port is not found, it is set to a negative |
|
* value. |
|
* |
|
* @param proto the buffer for the protocol |
|
* @param proto_size the size of the proto buffer |
|
* @param authorization the buffer for the authorization |
|
* @param authorization_size the size of the authorization buffer |
|
* @param hostname the buffer for the host name |
|
* @param hostname_size the size of the hostname buffer |
|
* @param port_ptr a pointer to store the port number in |
|
* @param path the buffer for the path |
|
* @param path_size the size of the path buffer |
|
* @param url the URL to split |
|
*/ |
|
void av_url_split(char *proto, int proto_size, |
|
char *authorization, int authorization_size, |
|
char *hostname, int hostname_size, |
|
int *port_ptr, |
|
char *path, int path_size, |
|
const char *url); |
|
|
|
|
|
/** |
|
* Print detailed information about the input or output format, such as |
|
* duration, bitrate, streams, container, programs, metadata, side data, |
|
* codec and time base. |
|
* |
|
* @param ic the context to analyze |
|
* @param index index of the stream to dump information about |
|
* @param url the URL to print, such as source or destination file |
|
* @param is_output Select whether the specified context is an input(0) or output(1) |
|
*/ |
|
void av_dump_format(AVFormatContext *ic, |
|
int index, |
|
const char *url, |
|
int is_output); |
|
|
|
|
|
#define AV_FRAME_FILENAME_FLAGS_MULTIPLE 1 ///< Allow multiple %d |
|
|
|
/** |
|
* Return in 'buf' the path with '%d' replaced by a number. |
|
* |
|
* Also handles the '%0nd' format where 'n' is the total number |
|
* of digits and '%%'. |
|
* |
|
* @param buf destination buffer |
|
* @param buf_size destination buffer size |
|
* @param path numbered sequence string |
|
* @param number frame number |
|
* @param flags AV_FRAME_FILENAME_FLAGS_* |
|
* @return 0 if OK, -1 on format error |
|
*/ |
|
int av_get_frame_filename2(char *buf, int buf_size, |
|
const char *path, int number, int flags); |
|
|
|
int av_get_frame_filename(char *buf, int buf_size, |
|
const char *path, int number); |
|
|
|
/** |
|
* Check whether filename actually is a numbered sequence generator. |
|
* |
|
* @param filename possible numbered sequence string |
|
* @return 1 if a valid numbered sequence string, 0 otherwise |
|
*/ |
|
int av_filename_number_test(const char *filename); |
|
|
|
/** |
|
* Generate an SDP for an RTP session. |
|
* |
|
* Note, this overwrites the id values of AVStreams in the muxer contexts |
|
* for getting unique dynamic payload types. |
|
* |
|
* @param ac array of AVFormatContexts describing the RTP streams. If the |
|
* array is composed by only one context, such context can contain |
|
* multiple AVStreams (one AVStream per RTP stream). Otherwise, |
|
* all the contexts in the array (an AVCodecContext per RTP stream) |
|
* must contain only one AVStream. |
|
* @param n_files number of AVCodecContexts contained in ac |
|
* @param buf buffer where the SDP will be stored (must be allocated by |
|
* the caller) |
|
* @param size the size of the buffer |
|
* @return 0 if OK, AVERROR_xxx on error |
|
*/ |
|
int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size); |
|
|
|
/** |
|
* Return a positive value if the given filename has one of the given |
|
* extensions, 0 otherwise. |
|
* |
|
* @param filename file name to check against the given extensions |
|
* @param extensions a comma-separated list of filename extensions |
|
*/ |
|
int av_match_ext(const char *filename, const char *extensions); |
|
|
|
/** |
|
* Test if the given container can store a codec. |
|
* |
|
* @param ofmt container to check for compatibility |
|
* @param codec_id codec to potentially store in container |
|
* @param std_compliance standards compliance level, one of FF_COMPLIANCE_* |
|
* |
|
* @return 1 if codec with ID codec_id can be stored in ofmt, 0 if it cannot. |
|
* A negative number if this information is not available. |
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*/ |
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int avformat_query_codec(const AVOutputFormat *ofmt, enum AVCodecID codec_id, |
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int std_compliance); |
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|
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/** |
|
* @defgroup riff_fourcc RIFF FourCCs |
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* @{ |
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* Get the tables mapping RIFF FourCCs to libavcodec AVCodecIDs. The tables are |
|
* meant to be passed to av_codec_get_id()/av_codec_get_tag() as in the |
|
* following code: |
|
* @code |
|
* uint32_t tag = MKTAG('H', '2', '6', '4'); |
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* const struct AVCodecTag *table[] = { avformat_get_riff_video_tags(), 0 }; |
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* enum AVCodecID id = av_codec_get_id(table, tag); |
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* @endcode |
|
*/ |
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/** |
|
* @return the table mapping RIFF FourCCs for video to libavcodec AVCodecID. |
|
*/ |
|
const struct AVCodecTag *avformat_get_riff_video_tags(void); |
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/** |
|
* @return the table mapping RIFF FourCCs for audio to AVCodecID. |
|
*/ |
|
const struct AVCodecTag *avformat_get_riff_audio_tags(void); |
|
/** |
|
* @return the table mapping MOV FourCCs for video to libavcodec AVCodecID. |
|
*/ |
|
const struct AVCodecTag *avformat_get_mov_video_tags(void); |
|
/** |
|
* @return the table mapping MOV FourCCs for audio to AVCodecID. |
|
*/ |
|
const struct AVCodecTag *avformat_get_mov_audio_tags(void); |
|
|
|
/** |
|
* @} |
|
*/ |
|
|
|
/** |
|
* Guess the sample aspect ratio of a frame, based on both the stream and the |
|
* frame aspect ratio. |
|
* |
|
* Since the frame aspect ratio is set by the codec but the stream aspect ratio |
|
* is set by the demuxer, these two may not be equal. This function tries to |
|
* return the value that you should use if you would like to display the frame. |
|
* |
|
* Basic logic is to use the stream aspect ratio if it is set to something sane |
|
* otherwise use the frame aspect ratio. This way a container setting, which is |
|
* usually easy to modify can override the coded value in the frames. |
|
* |
|
* @param format the format context which the stream is part of |
|
* @param stream the stream which the frame is part of |
|
* @param frame the frame with the aspect ratio to be determined |
|
* @return the guessed (valid) sample_aspect_ratio, 0/1 if no idea |
|
*/ |
|
AVRational av_guess_sample_aspect_ratio(AVFormatContext *format, AVStream *stream, AVFrame *frame); |
|
|
|
/** |
|
* Guess the frame rate, based on both the container and codec information. |
|
* |
|
* @param ctx the format context which the stream is part of |
|
* @param stream the stream which the frame is part of |
|
* @param frame the frame for which the frame rate should be determined, may be NULL |
|
* @return the guessed (valid) frame rate, 0/1 if no idea |
|
*/ |
|
AVRational av_guess_frame_rate(AVFormatContext *ctx, AVStream *stream, AVFrame *frame); |
|
|
|
/** |
|
* Check if the stream st contained in s is matched by the stream specifier |
|
* spec. |
|
* |
|
* See the "stream specifiers" chapter in the documentation for the syntax |
|
* of spec. |
|
* |
|
* @return >0 if st is matched by spec; |
|
* 0 if st is not matched by spec; |
|
* AVERROR code if spec is invalid |
|
* |
|
* @note A stream specifier can match several streams in the format. |
|
*/ |
|
int avformat_match_stream_specifier(AVFormatContext *s, AVStream *st, |
|
const char *spec); |
|
|
|
int avformat_queue_attached_pictures(AVFormatContext *s); |
|
|
|
enum AVTimebaseSource { |
|
AVFMT_TBCF_AUTO = -1, |
|
AVFMT_TBCF_DECODER, |
|
AVFMT_TBCF_DEMUXER, |
|
#if FF_API_R_FRAME_RATE |
|
AVFMT_TBCF_R_FRAMERATE, |
|
#endif |
|
}; |
|
|
|
/** |
|
* Transfer internal timing information from one stream to another. |
|
* |
|
* This function is useful when doing stream copy. |
|
* |
|
* @param ofmt target output format for ost |
|
* @param ost output stream which needs timings copy and adjustments |
|
* @param ist reference input stream to copy timings from |
|
* @param copy_tb define from where the stream codec timebase needs to be imported |
|
*/ |
|
int avformat_transfer_internal_stream_timing_info(const AVOutputFormat *ofmt, |
|
AVStream *ost, const AVStream *ist, |
|
enum AVTimebaseSource copy_tb); |
|
|
|
/** |
|
* Get the internal codec timebase from a stream. |
|
* |
|
* @param st input stream to extract the timebase from |
|
*/ |
|
AVRational av_stream_get_codec_timebase(const AVStream *st); |
|
|
|
/** |
|
* @} |
|
*/ |
|
|
|
#endif /* AVFORMAT_AVFORMAT_H */
|
|
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