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1301 lines
47 KiB
1301 lines
47 KiB
/* |
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* filter layer |
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* Copyright (c) 2007 Bobby Bingham |
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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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#ifndef AVFILTER_AVFILTER_H |
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#define AVFILTER_AVFILTER_H |
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/** |
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* @file |
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* @ingroup lavfi |
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* external API header |
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*/ |
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/** |
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* @defgroup lavfi Libavfilter |
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* @{ |
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*/ |
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#include <stddef.h> |
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#include "libavutil/avutil.h" |
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#include "libavutil/dict.h" |
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#include "libavutil/frame.h" |
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#include "libavutil/log.h" |
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#include "libavutil/samplefmt.h" |
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#include "libavutil/pixfmt.h" |
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#include "libavutil/rational.h" |
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#include "libavfilter/version.h" |
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/** |
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* Return the LIBAVFILTER_VERSION_INT constant. |
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*/ |
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unsigned avfilter_version(void); |
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/** |
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* Return the libavfilter build-time configuration. |
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*/ |
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const char *avfilter_configuration(void); |
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/** |
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* Return the libavfilter license. |
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*/ |
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const char *avfilter_license(void); |
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typedef struct AVFilterContext AVFilterContext; |
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typedef struct AVFilterLink AVFilterLink; |
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typedef struct AVFilterPad AVFilterPad; |
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typedef struct AVFilterFormats AVFilterFormats; |
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#if FF_API_AVFILTERBUFFER |
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/** |
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* A reference-counted buffer data type used by the filter system. Filters |
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* should not store pointers to this structure directly, but instead use the |
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* AVFilterBufferRef structure below. |
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*/ |
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typedef struct AVFilterBuffer { |
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uint8_t *data[8]; ///< buffer data for each plane/channel |
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|
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/** |
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* pointers to the data planes/channels. |
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* |
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* For video, this should simply point to data[]. |
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* |
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* For planar audio, each channel has a separate data pointer, and |
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* linesize[0] contains the size of each channel buffer. |
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* For packed audio, there is just one data pointer, and linesize[0] |
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* contains the total size of the buffer for all channels. |
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* |
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* Note: Both data and extended_data will always be set, but for planar |
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* audio with more channels that can fit in data, extended_data must be used |
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* in order to access all channels. |
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*/ |
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uint8_t **extended_data; |
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int linesize[8]; ///< number of bytes per line |
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/** private data to be used by a custom free function */ |
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void *priv; |
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/** |
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* A pointer to the function to deallocate this buffer if the default |
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* function is not sufficient. This could, for example, add the memory |
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* back into a memory pool to be reused later without the overhead of |
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* reallocating it from scratch. |
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*/ |
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void (*free)(struct AVFilterBuffer *buf); |
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int format; ///< media format |
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int w, h; ///< width and height of the allocated buffer |
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unsigned refcount; ///< number of references to this buffer |
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} AVFilterBuffer; |
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#define AV_PERM_READ 0x01 ///< can read from the buffer |
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#define AV_PERM_WRITE 0x02 ///< can write to the buffer |
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#define AV_PERM_PRESERVE 0x04 ///< nobody else can overwrite the buffer |
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#define AV_PERM_REUSE 0x08 ///< can output the buffer multiple times, with the same contents each time |
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#define AV_PERM_REUSE2 0x10 ///< can output the buffer multiple times, modified each time |
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#define AV_PERM_NEG_LINESIZES 0x20 ///< the buffer requested can have negative linesizes |
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#define AV_PERM_ALIGN 0x40 ///< the buffer must be aligned |
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#define AVFILTER_ALIGN 16 //not part of ABI |
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/** |
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* Audio specific properties in a reference to an AVFilterBuffer. Since |
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* AVFilterBufferRef is common to different media formats, audio specific |
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* per reference properties must be separated out. |
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*/ |
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typedef struct AVFilterBufferRefAudioProps { |
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uint64_t channel_layout; ///< channel layout of audio buffer |
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int nb_samples; ///< number of audio samples per channel |
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int sample_rate; ///< audio buffer sample rate |
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int channels; ///< number of channels (do not access directly) |
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} AVFilterBufferRefAudioProps; |
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/** |
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* Video specific properties in a reference to an AVFilterBuffer. Since |
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* AVFilterBufferRef is common to different media formats, video specific |
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* per reference properties must be separated out. |
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*/ |
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typedef struct AVFilterBufferRefVideoProps { |
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int w; ///< image width |
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int h; ///< image height |
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AVRational sample_aspect_ratio; ///< sample aspect ratio |
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int interlaced; ///< is frame interlaced |
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int top_field_first; ///< field order |
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enum AVPictureType pict_type; ///< picture type of the frame |
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int key_frame; ///< 1 -> keyframe, 0-> not |
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int qp_table_linesize; ///< qp_table stride |
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int qp_table_size; ///< qp_table size |
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int8_t *qp_table; ///< array of Quantization Parameters |
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} AVFilterBufferRefVideoProps; |
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/** |
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* A reference to an AVFilterBuffer. Since filters can manipulate the origin of |
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* a buffer to, for example, crop image without any memcpy, the buffer origin |
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* and dimensions are per-reference properties. Linesize is also useful for |
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* image flipping, frame to field filters, etc, and so is also per-reference. |
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* |
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* TODO: add anything necessary for frame reordering |
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*/ |
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typedef struct AVFilterBufferRef { |
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AVFilterBuffer *buf; ///< the buffer that this is a reference to |
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uint8_t *data[8]; ///< picture/audio data for each plane |
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/** |
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* pointers to the data planes/channels. |
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* |
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* For video, this should simply point to data[]. |
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* |
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* For planar audio, each channel has a separate data pointer, and |
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* linesize[0] contains the size of each channel buffer. |
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* For packed audio, there is just one data pointer, and linesize[0] |
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* contains the total size of the buffer for all channels. |
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* |
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* Note: Both data and extended_data will always be set, but for planar |
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* audio with more channels that can fit in data, extended_data must be used |
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* in order to access all channels. |
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*/ |
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uint8_t **extended_data; |
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int linesize[8]; ///< number of bytes per line |
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AVFilterBufferRefVideoProps *video; ///< video buffer specific properties |
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AVFilterBufferRefAudioProps *audio; ///< audio buffer specific properties |
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/** |
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* presentation timestamp. The time unit may change during |
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* filtering, as it is specified in the link and the filter code |
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* may need to rescale the PTS accordingly. |
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*/ |
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int64_t pts; |
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int64_t pos; ///< byte position in stream, -1 if unknown |
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int format; ///< media format |
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int perms; ///< permissions, see the AV_PERM_* flags |
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enum AVMediaType type; ///< media type of buffer data |
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AVDictionary *metadata; ///< dictionary containing metadata key=value tags |
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} AVFilterBufferRef; |
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/** |
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* Copy properties of src to dst, without copying the actual data |
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*/ |
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attribute_deprecated |
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void avfilter_copy_buffer_ref_props(AVFilterBufferRef *dst, AVFilterBufferRef *src); |
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/** |
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* Add a new reference to a buffer. |
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* |
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* @param ref an existing reference to the buffer |
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* @param pmask a bitmask containing the allowable permissions in the new |
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* reference |
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* @return a new reference to the buffer with the same properties as the |
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* old, excluding any permissions denied by pmask |
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*/ |
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attribute_deprecated |
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AVFilterBufferRef *avfilter_ref_buffer(AVFilterBufferRef *ref, int pmask); |
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/** |
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* Remove a reference to a buffer. If this is the last reference to the |
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* buffer, the buffer itself is also automatically freed. |
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* |
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* @param ref reference to the buffer, may be NULL |
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* |
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* @note it is recommended to use avfilter_unref_bufferp() instead of this |
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* function |
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*/ |
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attribute_deprecated |
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void avfilter_unref_buffer(AVFilterBufferRef *ref); |
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/** |
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* Remove a reference to a buffer and set the pointer to NULL. |
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* If this is the last reference to the buffer, the buffer itself |
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* is also automatically freed. |
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* |
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* @param ref pointer to the buffer reference |
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*/ |
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attribute_deprecated |
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void avfilter_unref_bufferp(AVFilterBufferRef **ref); |
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#endif |
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/** |
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* Get the number of channels of a buffer reference. |
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*/ |
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attribute_deprecated |
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int avfilter_ref_get_channels(AVFilterBufferRef *ref); |
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#if FF_API_AVFILTERPAD_PUBLIC |
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/** |
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* A filter pad used for either input or output. |
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* |
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* See doc/filter_design.txt for details on how to implement the methods. |
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* |
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* @warning this struct might be removed from public API. |
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* users should call avfilter_pad_get_name() and avfilter_pad_get_type() |
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* to access the name and type fields; there should be no need to access |
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* any other fields from outside of libavfilter. |
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*/ |
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struct AVFilterPad { |
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/** |
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* Pad name. The name is unique among inputs and among outputs, but an |
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* input may have the same name as an output. This may be NULL if this |
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* pad has no need to ever be referenced by name. |
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*/ |
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const char *name; |
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/** |
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* AVFilterPad type. |
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*/ |
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enum AVMediaType type; |
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/** |
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* Input pads: |
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* Minimum required permissions on incoming buffers. Any buffer with |
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* insufficient permissions will be automatically copied by the filter |
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* system to a new buffer which provides the needed access permissions. |
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* |
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* Output pads: |
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* Guaranteed permissions on outgoing buffers. Any buffer pushed on the |
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* link must have at least these permissions; this fact is checked by |
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* asserts. It can be used to optimize buffer allocation. |
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*/ |
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attribute_deprecated int min_perms; |
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/** |
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* Input pads: |
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* Permissions which are not accepted on incoming buffers. Any buffer |
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* which has any of these permissions set will be automatically copied |
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* by the filter system to a new buffer which does not have those |
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* permissions. This can be used to easily disallow buffers with |
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* AV_PERM_REUSE. |
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* |
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* Output pads: |
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* Permissions which are automatically removed on outgoing buffers. It |
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* can be used to optimize buffer allocation. |
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*/ |
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attribute_deprecated int rej_perms; |
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/** |
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* @deprecated unused |
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*/ |
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int (*start_frame)(AVFilterLink *link, AVFilterBufferRef *picref); |
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/** |
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* Callback function to get a video buffer. If NULL, the filter system will |
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* use ff_default_get_video_buffer(). |
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* |
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* Input video pads only. |
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*/ |
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AVFrame *(*get_video_buffer)(AVFilterLink *link, int w, int h); |
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/** |
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* Callback function to get an audio buffer. If NULL, the filter system will |
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* use ff_default_get_audio_buffer(). |
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* |
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* Input audio pads only. |
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*/ |
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AVFrame *(*get_audio_buffer)(AVFilterLink *link, int nb_samples); |
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/** |
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* @deprecated unused |
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*/ |
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int (*end_frame)(AVFilterLink *link); |
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/** |
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* @deprecated unused |
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*/ |
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int (*draw_slice)(AVFilterLink *link, int y, int height, int slice_dir); |
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/** |
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* Filtering callback. This is where a filter receives a frame with |
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* audio/video data and should do its processing. |
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* |
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* Input pads only. |
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* |
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* @return >= 0 on success, a negative AVERROR on error. This function |
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* must ensure that frame is properly unreferenced on error if it |
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* hasn't been passed on to another filter. |
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*/ |
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int (*filter_frame)(AVFilterLink *link, AVFrame *frame); |
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/** |
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* Frame poll callback. This returns the number of immediately available |
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* samples. It should return a positive value if the next request_frame() |
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* is guaranteed to return one frame (with no delay). |
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* |
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* Defaults to just calling the source poll_frame() method. |
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* |
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* Output pads only. |
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*/ |
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int (*poll_frame)(AVFilterLink *link); |
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/** |
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* Frame request callback. A call to this should result in at least one |
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* frame being output over the given link. This should return zero on |
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* success, and another value on error. |
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* See ff_request_frame() for the error codes with a specific |
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* meaning. |
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* |
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* Output pads only. |
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*/ |
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int (*request_frame)(AVFilterLink *link); |
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/** |
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* Link configuration callback. |
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* |
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* For output pads, this should set the following link properties: |
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* video: width, height, sample_aspect_ratio, time_base |
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* audio: sample_rate. |
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* |
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* This should NOT set properties such as format, channel_layout, etc which |
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* are negotiated between filters by the filter system using the |
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* query_formats() callback before this function is called. |
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* |
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* For input pads, this should check the properties of the link, and update |
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* the filter's internal state as necessary. |
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* |
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* For both input and output pads, this should return zero on success, |
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* and another value on error. |
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*/ |
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int (*config_props)(AVFilterLink *link); |
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/** |
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* The filter expects a fifo to be inserted on its input link, |
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* typically because it has a delay. |
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* |
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* input pads only. |
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*/ |
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int needs_fifo; |
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int needs_writable; |
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}; |
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#endif |
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/** |
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* Get the number of elements in a NULL-terminated array of AVFilterPads (e.g. |
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* AVFilter.inputs/outputs). |
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*/ |
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int avfilter_pad_count(const AVFilterPad *pads); |
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/** |
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* Get the name of an AVFilterPad. |
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* |
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* @param pads an array of AVFilterPads |
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* @param pad_idx index of the pad in the array it; is the caller's |
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* responsibility to ensure the index is valid |
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* |
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* @return name of the pad_idx'th pad in pads |
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*/ |
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const char *avfilter_pad_get_name(const AVFilterPad *pads, int pad_idx); |
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/** |
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* Get the type of an AVFilterPad. |
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* |
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* @param pads an array of AVFilterPads |
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* @param pad_idx index of the pad in the array; it is the caller's |
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* responsibility to ensure the index is valid |
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* |
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* @return type of the pad_idx'th pad in pads |
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*/ |
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enum AVMediaType avfilter_pad_get_type(const AVFilterPad *pads, int pad_idx); |
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/** |
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* The number of the filter inputs is not determined just by AVFilter.inputs. |
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* The filter might add additional inputs during initialization depending on the |
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* options supplied to it. |
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*/ |
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#define AVFILTER_FLAG_DYNAMIC_INPUTS (1 << 0) |
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/** |
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* The number of the filter outputs is not determined just by AVFilter.outputs. |
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* The filter might add additional outputs during initialization depending on |
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* the options supplied to it. |
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*/ |
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#define AVFILTER_FLAG_DYNAMIC_OUTPUTS (1 << 1) |
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/** |
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* Some filters support a generic "enable" expression option that can be used |
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* to enable or disable a filter in the timeline. Filters supporting this |
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* option have this flag set. When the enable expression is false, the default |
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* no-op filter_frame() function is called in place of the filter_frame() |
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* callback defined on each input pad, thus the frame is passed unchanged to |
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* the next filters. |
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*/ |
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#define AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC (1 << 16) |
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/** |
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* Same as AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC, except that the filter will |
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* have its filter_frame() callback(s) called as usual even when the enable |
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* expression is false. The filter will disable filtering within the |
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* filter_frame() callback(s) itself, for example executing code depending on |
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* the AVFilterContext->is_disabled value. |
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*/ |
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#define AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL (1 << 17) |
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/** |
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* Handy mask to test whether the filter supports or no the timeline feature |
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* (internally or generically). |
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*/ |
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#define AVFILTER_FLAG_SUPPORT_TIMELINE (AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC | AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL) |
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/** |
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* Filter definition. This defines the pads a filter contains, and all the |
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* callback functions used to interact with the filter. |
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*/ |
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typedef struct AVFilter { |
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const char *name; ///< filter name |
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/** |
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* A description for the filter. You should use the |
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* NULL_IF_CONFIG_SMALL() macro to define it. |
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*/ |
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const char *description; |
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const AVFilterPad *inputs; ///< NULL terminated list of inputs. NULL if none |
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const AVFilterPad *outputs; ///< NULL terminated list of outputs. NULL if none |
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/** |
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* A class for the private data, used to access filter private |
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* AVOptions. |
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*/ |
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const AVClass *priv_class; |
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/** |
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* A combination of AVFILTER_FLAG_* |
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*/ |
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int flags; |
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/***************************************************************** |
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* All fields below this line are not part of the public API. They |
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* may not be used outside of libavfilter and can be changed and |
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* removed at will. |
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* New public fields should be added right above. |
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***************************************************************** |
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*/ |
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/** |
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* Filter initialization function. Called when all the options have been |
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* set. |
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*/ |
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int (*init)(AVFilterContext *ctx); |
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/** |
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* Should be set instead of init by the filters that want to pass a |
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* dictionary of AVOptions to nested contexts that are allocated in |
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* init. |
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*/ |
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int (*init_dict)(AVFilterContext *ctx, AVDictionary **options); |
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/** |
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* Filter uninitialization function. Should deallocate any memory held |
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* by the filter, release any buffer references, etc. This does not need |
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* to deallocate the AVFilterContext->priv memory itself. |
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*/ |
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void (*uninit)(AVFilterContext *ctx); |
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/** |
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* Queries formats/layouts supported by the filter and its pads, and sets |
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* the in_formats/in_chlayouts for links connected to its output pads, |
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* and out_formats/out_chlayouts for links connected to its input pads. |
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* |
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* @return zero on success, a negative value corresponding to an |
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* AVERROR code otherwise |
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*/ |
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int (*query_formats)(AVFilterContext *); |
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int priv_size; ///< size of private data to allocate for the filter |
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struct AVFilter *next; |
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/** |
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* Make the filter instance process a command. |
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* |
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* @param cmd the command to process, for handling simplicity all commands must be alphanumeric only |
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* @param arg the argument for the command |
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* @param res a buffer with size res_size where the filter(s) can return a response. This must not change when the command is not supported. |
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* @param flags if AVFILTER_CMD_FLAG_FAST is set and the command would be |
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* time consuming then a filter should treat it like an unsupported command |
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* |
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* @returns >=0 on success otherwise an error code. |
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* AVERROR(ENOSYS) on unsupported commands |
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*/ |
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int (*process_command)(AVFilterContext *, const char *cmd, const char *arg, char *res, int res_len, int flags); |
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/** |
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* Filter initialization function, alternative to the init() |
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* callback. Args contains the user-supplied parameters, opaque is |
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* used for providing binary data. |
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*/ |
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int (*init_opaque)(AVFilterContext *ctx, void *opaque); |
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} AVFilter; |
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/** An instance of a filter */ |
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struct AVFilterContext { |
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const AVClass *av_class; ///< needed for av_log() and filters common options |
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const AVFilter *filter; ///< the AVFilter of which this is an instance |
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char *name; ///< name of this filter instance |
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AVFilterPad *input_pads; ///< array of input pads |
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AVFilterLink **inputs; ///< array of pointers to input links |
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#if FF_API_FOO_COUNT |
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unsigned input_count; ///< @deprecated use nb_inputs |
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#endif |
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unsigned nb_inputs; ///< number of input pads |
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AVFilterPad *output_pads; ///< array of output pads |
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AVFilterLink **outputs; ///< array of pointers to output links |
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#if FF_API_FOO_COUNT |
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unsigned output_count; ///< @deprecated use nb_outputs |
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#endif |
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unsigned nb_outputs; ///< number of output pads |
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void *priv; ///< private data for use by the filter |
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struct AVFilterGraph *graph; ///< filtergraph this filter belongs to |
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struct AVFilterCommand *command_queue; |
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char *enable_str; ///< enable expression string |
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void *enable; ///< parsed expression (AVExpr*) |
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double *var_values; ///< variable values for the enable expression |
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int is_disabled; ///< the enabled state from the last expression evaluation |
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}; |
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/** |
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* A link between two filters. This contains pointers to the source and |
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* destination filters between which this link exists, and the indexes of |
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* the pads involved. In addition, this link also contains the parameters |
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* which have been negotiated and agreed upon between the filter, such as |
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* image dimensions, format, etc. |
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*/ |
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struct AVFilterLink { |
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AVFilterContext *src; ///< source filter |
|
AVFilterPad *srcpad; ///< output pad on the source filter |
|
|
|
AVFilterContext *dst; ///< dest filter |
|
AVFilterPad *dstpad; ///< input pad on the dest filter |
|
|
|
enum AVMediaType type; ///< filter media type |
|
|
|
/* These parameters apply only to video */ |
|
int w; ///< agreed upon image width |
|
int h; ///< agreed upon image height |
|
AVRational sample_aspect_ratio; ///< agreed upon sample aspect ratio |
|
/* These parameters apply only to audio */ |
|
uint64_t channel_layout; ///< channel layout of current buffer (see libavutil/channel_layout.h) |
|
int sample_rate; ///< samples per second |
|
|
|
int format; ///< agreed upon media format |
|
|
|
/** |
|
* Define the time base used by the PTS of the frames/samples |
|
* which will pass through this link. |
|
* During the configuration stage, each filter is supposed to |
|
* change only the output timebase, while the timebase of the |
|
* input link is assumed to be an unchangeable property. |
|
*/ |
|
AVRational time_base; |
|
|
|
/***************************************************************** |
|
* All fields below this line are not part of the public API. They |
|
* may not be used outside of libavfilter and can be changed and |
|
* removed at will. |
|
* New public fields should be added right above. |
|
***************************************************************** |
|
*/ |
|
/** |
|
* Lists of formats and channel layouts supported by the input and output |
|
* filters respectively. These lists are used for negotiating the format |
|
* to actually be used, which will be loaded into the format and |
|
* channel_layout members, above, when chosen. |
|
* |
|
*/ |
|
AVFilterFormats *in_formats; |
|
AVFilterFormats *out_formats; |
|
|
|
/** |
|
* Lists of channel layouts and sample rates used for automatic |
|
* negotiation. |
|
*/ |
|
AVFilterFormats *in_samplerates; |
|
AVFilterFormats *out_samplerates; |
|
struct AVFilterChannelLayouts *in_channel_layouts; |
|
struct AVFilterChannelLayouts *out_channel_layouts; |
|
|
|
/** |
|
* Audio only, the destination filter sets this to a non-zero value to |
|
* request that buffers with the given number of samples should be sent to |
|
* it. AVFilterPad.needs_fifo must also be set on the corresponding input |
|
* pad. |
|
* Last buffer before EOF will be padded with silence. |
|
*/ |
|
int request_samples; |
|
|
|
/** stage of the initialization of the link properties (dimensions, etc) */ |
|
enum { |
|
AVLINK_UNINIT = 0, ///< not started |
|
AVLINK_STARTINIT, ///< started, but incomplete |
|
AVLINK_INIT ///< complete |
|
} init_state; |
|
|
|
struct AVFilterPool *pool; |
|
|
|
/** |
|
* Graph the filter belongs to. |
|
*/ |
|
struct AVFilterGraph *graph; |
|
|
|
/** |
|
* Current timestamp of the link, as defined by the most recent |
|
* frame(s), in AV_TIME_BASE units. |
|
*/ |
|
int64_t current_pts; |
|
|
|
/** |
|
* Index in the age array. |
|
*/ |
|
int age_index; |
|
|
|
/** |
|
* Frame rate of the stream on the link, or 1/0 if unknown; |
|
* if left to 0/0, will be automatically be copied from the first input |
|
* of the source filter if it exists. |
|
* |
|
* Sources should set it to the best estimation of the real frame rate. |
|
* Filters should update it if necessary depending on their function. |
|
* Sinks can use it to set a default output frame rate. |
|
* It is similar to the r_frame_rate field in AVStream. |
|
*/ |
|
AVRational frame_rate; |
|
|
|
/** |
|
* Buffer partially filled with samples to achieve a fixed/minimum size. |
|
*/ |
|
AVFrame *partial_buf; |
|
|
|
/** |
|
* Size of the partial buffer to allocate. |
|
* Must be between min_samples and max_samples. |
|
*/ |
|
int partial_buf_size; |
|
|
|
/** |
|
* Minimum number of samples to filter at once. If filter_frame() is |
|
* called with fewer samples, it will accumulate them in partial_buf. |
|
* This field and the related ones must not be changed after filtering |
|
* has started. |
|
* If 0, all related fields are ignored. |
|
*/ |
|
int min_samples; |
|
|
|
/** |
|
* Maximum number of samples to filter at once. If filter_frame() is |
|
* called with more samples, it will split them. |
|
*/ |
|
int max_samples; |
|
|
|
/** |
|
* The buffer reference currently being received across the link by the |
|
* destination filter. This is used internally by the filter system to |
|
* allow automatic copying of buffers which do not have sufficient |
|
* permissions for the destination. This should not be accessed directly |
|
* by the filters. |
|
*/ |
|
AVFilterBufferRef *cur_buf_copy; |
|
|
|
/** |
|
* True if the link is closed. |
|
* If set, all attemps of start_frame, filter_frame or request_frame |
|
* will fail with AVERROR_EOF, and if necessary the reference will be |
|
* destroyed. |
|
* If request_frame returns AVERROR_EOF, this flag is set on the |
|
* corresponding link. |
|
* It can be set also be set by either the source or the destination |
|
* filter. |
|
*/ |
|
int closed; |
|
|
|
/** |
|
* Number of channels. |
|
*/ |
|
int channels; |
|
|
|
/** |
|
* True if a frame is being requested on the link. |
|
* Used internally by the framework. |
|
*/ |
|
unsigned frame_requested; |
|
|
|
/** |
|
* Link processing flags. |
|
*/ |
|
unsigned flags; |
|
|
|
/** |
|
* Number of past frames sent through the link. |
|
*/ |
|
int64_t frame_count; |
|
}; |
|
|
|
/** |
|
* Link two filters together. |
|
* |
|
* @param src the source filter |
|
* @param srcpad index of the output pad on the source filter |
|
* @param dst the destination filter |
|
* @param dstpad index of the input pad on the destination filter |
|
* @return zero on success |
|
*/ |
|
int avfilter_link(AVFilterContext *src, unsigned srcpad, |
|
AVFilterContext *dst, unsigned dstpad); |
|
|
|
/** |
|
* Free the link in *link, and set its pointer to NULL. |
|
*/ |
|
void avfilter_link_free(AVFilterLink **link); |
|
|
|
/** |
|
* Get the number of channels of a link. |
|
*/ |
|
int avfilter_link_get_channels(AVFilterLink *link); |
|
|
|
/** |
|
* Set the closed field of a link. |
|
*/ |
|
void avfilter_link_set_closed(AVFilterLink *link, int closed); |
|
|
|
/** |
|
* Negotiate the media format, dimensions, etc of all inputs to a filter. |
|
* |
|
* @param filter the filter to negotiate the properties for its inputs |
|
* @return zero on successful negotiation |
|
*/ |
|
int avfilter_config_links(AVFilterContext *filter); |
|
|
|
#if FF_API_AVFILTERBUFFER |
|
/** |
|
* Create a buffer reference wrapped around an already allocated image |
|
* buffer. |
|
* |
|
* @param data pointers to the planes of the image to reference |
|
* @param linesize linesizes for the planes of the image to reference |
|
* @param perms the required access permissions |
|
* @param w the width of the image specified by the data and linesize arrays |
|
* @param h the height of the image specified by the data and linesize arrays |
|
* @param format the pixel format of the image specified by the data and linesize arrays |
|
*/ |
|
attribute_deprecated |
|
AVFilterBufferRef * |
|
avfilter_get_video_buffer_ref_from_arrays(uint8_t * const data[4], const int linesize[4], int perms, |
|
int w, int h, enum AVPixelFormat format); |
|
|
|
/** |
|
* Create an audio buffer reference wrapped around an already |
|
* allocated samples buffer. |
|
* |
|
* See avfilter_get_audio_buffer_ref_from_arrays_channels() for a version |
|
* that can handle unknown channel layouts. |
|
* |
|
* @param data pointers to the samples plane buffers |
|
* @param linesize linesize for the samples plane buffers |
|
* @param perms the required access permissions |
|
* @param nb_samples number of samples per channel |
|
* @param sample_fmt the format of each sample in the buffer to allocate |
|
* @param channel_layout the channel layout of the buffer |
|
*/ |
|
attribute_deprecated |
|
AVFilterBufferRef *avfilter_get_audio_buffer_ref_from_arrays(uint8_t **data, |
|
int linesize, |
|
int perms, |
|
int nb_samples, |
|
enum AVSampleFormat sample_fmt, |
|
uint64_t channel_layout); |
|
/** |
|
* Create an audio buffer reference wrapped around an already |
|
* allocated samples buffer. |
|
* |
|
* @param data pointers to the samples plane buffers |
|
* @param linesize linesize for the samples plane buffers |
|
* @param perms the required access permissions |
|
* @param nb_samples number of samples per channel |
|
* @param sample_fmt the format of each sample in the buffer to allocate |
|
* @param channels the number of channels of the buffer |
|
* @param channel_layout the channel layout of the buffer, |
|
* must be either 0 or consistent with channels |
|
*/ |
|
attribute_deprecated |
|
AVFilterBufferRef *avfilter_get_audio_buffer_ref_from_arrays_channels(uint8_t **data, |
|
int linesize, |
|
int perms, |
|
int nb_samples, |
|
enum AVSampleFormat sample_fmt, |
|
int channels, |
|
uint64_t channel_layout); |
|
|
|
#endif |
|
|
|
|
|
#define AVFILTER_CMD_FLAG_ONE 1 ///< Stop once a filter understood the command (for target=all for example), fast filters are favored automatically |
|
#define AVFILTER_CMD_FLAG_FAST 2 ///< Only execute command when its fast (like a video out that supports contrast adjustment in hw) |
|
|
|
/** |
|
* Make the filter instance process a command. |
|
* It is recommended to use avfilter_graph_send_command(). |
|
*/ |
|
int avfilter_process_command(AVFilterContext *filter, const char *cmd, const char *arg, char *res, int res_len, int flags); |
|
|
|
/** Initialize the filter system. Register all builtin filters. */ |
|
void avfilter_register_all(void); |
|
|
|
#if FF_API_OLD_FILTER_REGISTER |
|
/** Uninitialize the filter system. Unregister all filters. */ |
|
attribute_deprecated |
|
void avfilter_uninit(void); |
|
#endif |
|
|
|
/** |
|
* Register a filter. This is only needed if you plan to use |
|
* avfilter_get_by_name later to lookup the AVFilter structure by name. A |
|
* filter can still by instantiated with avfilter_graph_alloc_filter even if it |
|
* is not registered. |
|
* |
|
* @param filter the filter to register |
|
* @return 0 if the registration was successful, a negative value |
|
* otherwise |
|
*/ |
|
int avfilter_register(AVFilter *filter); |
|
|
|
/** |
|
* Get a filter definition matching the given name. |
|
* |
|
* @param name the filter name to find |
|
* @return the filter definition, if any matching one is registered. |
|
* NULL if none found. |
|
*/ |
|
AVFilter *avfilter_get_by_name(const char *name); |
|
|
|
/** |
|
* Iterate over all registered filters. |
|
* @return If prev is non-NULL, next registered filter after prev or NULL if |
|
* prev is the last filter. If prev is NULL, return the first registered filter. |
|
*/ |
|
const AVFilter *avfilter_next(const AVFilter *prev); |
|
|
|
#if FF_API_OLD_FILTER_REGISTER |
|
/** |
|
* If filter is NULL, returns a pointer to the first registered filter pointer, |
|
* if filter is non-NULL, returns the next pointer after filter. |
|
* If the returned pointer points to NULL, the last registered filter |
|
* was already reached. |
|
* @deprecated use avfilter_next() |
|
*/ |
|
attribute_deprecated |
|
AVFilter **av_filter_next(AVFilter **filter); |
|
#endif |
|
|
|
#if FF_API_AVFILTER_OPEN |
|
/** |
|
* Create a filter instance. |
|
* |
|
* @param filter_ctx put here a pointer to the created filter context |
|
* on success, NULL on failure |
|
* @param filter the filter to create an instance of |
|
* @param inst_name Name to give to the new instance. Can be NULL for none. |
|
* @return >= 0 in case of success, a negative error code otherwise |
|
* @deprecated use avfilter_graph_alloc_filter() instead |
|
*/ |
|
attribute_deprecated |
|
int avfilter_open(AVFilterContext **filter_ctx, AVFilter *filter, const char *inst_name); |
|
#endif |
|
|
|
|
|
#if FF_API_AVFILTER_INIT_FILTER |
|
/** |
|
* Initialize a filter. |
|
* |
|
* @param filter the filter to initialize |
|
* @param args A string of parameters to use when initializing the filter. |
|
* The format and meaning of this string varies by filter. |
|
* @param opaque Any extra non-string data needed by the filter. The meaning |
|
* of this parameter varies by filter. |
|
* @return zero on success |
|
*/ |
|
attribute_deprecated |
|
int avfilter_init_filter(AVFilterContext *filter, const char *args, void *opaque); |
|
#endif |
|
|
|
/** |
|
* Initialize a filter with the supplied parameters. |
|
* |
|
* @param ctx uninitialized filter context to initialize |
|
* @param args Options to initialize the filter with. This must be a |
|
* ':'-separated list of options in the 'key=value' form. |
|
* May be NULL if the options have been set directly using the |
|
* AVOptions API or there are no options that need to be set. |
|
* @return 0 on success, a negative AVERROR on failure |
|
*/ |
|
int avfilter_init_str(AVFilterContext *ctx, const char *args); |
|
|
|
/** |
|
* Initialize a filter with the supplied dictionary of options. |
|
* |
|
* @param ctx uninitialized filter context to initialize |
|
* @param options An AVDictionary filled with options for this filter. On |
|
* return this parameter will be destroyed and replaced with |
|
* a dict containing options that were not found. This dictionary |
|
* must be freed by the caller. |
|
* May be NULL, then this function is equivalent to |
|
* avfilter_init_str() with the second parameter set to NULL. |
|
* @return 0 on success, a negative AVERROR on failure |
|
* |
|
* @note This function and avfilter_init_str() do essentially the same thing, |
|
* the difference is in manner in which the options are passed. It is up to the |
|
* calling code to choose whichever is more preferable. The two functions also |
|
* behave differently when some of the provided options are not declared as |
|
* supported by the filter. In such a case, avfilter_init_str() will fail, but |
|
* this function will leave those extra options in the options AVDictionary and |
|
* continue as usual. |
|
*/ |
|
int avfilter_init_dict(AVFilterContext *ctx, AVDictionary **options); |
|
|
|
/** |
|
* Free a filter context. This will also remove the filter from its |
|
* filtergraph's list of filters. |
|
* |
|
* @param filter the filter to free |
|
*/ |
|
void avfilter_free(AVFilterContext *filter); |
|
|
|
/** |
|
* Insert a filter in the middle of an existing link. |
|
* |
|
* @param link the link into which the filter should be inserted |
|
* @param filt the filter to be inserted |
|
* @param filt_srcpad_idx the input pad on the filter to connect |
|
* @param filt_dstpad_idx the output pad on the filter to connect |
|
* @return zero on success |
|
*/ |
|
int avfilter_insert_filter(AVFilterLink *link, AVFilterContext *filt, |
|
unsigned filt_srcpad_idx, unsigned filt_dstpad_idx); |
|
|
|
#if FF_API_AVFILTERBUFFER |
|
/** |
|
* Copy the frame properties of src to dst, without copying the actual |
|
* image data. |
|
* |
|
* @return 0 on success, a negative number on error. |
|
*/ |
|
attribute_deprecated |
|
int avfilter_copy_frame_props(AVFilterBufferRef *dst, const AVFrame *src); |
|
|
|
/** |
|
* Copy the frame properties and data pointers of src to dst, without copying |
|
* the actual data. |
|
* |
|
* @return 0 on success, a negative number on error. |
|
*/ |
|
attribute_deprecated |
|
int avfilter_copy_buf_props(AVFrame *dst, const AVFilterBufferRef *src); |
|
#endif |
|
|
|
/** |
|
* @return AVClass for AVFilterContext. |
|
* |
|
* @see av_opt_find(). |
|
*/ |
|
const AVClass *avfilter_get_class(void); |
|
|
|
typedef struct AVFilterGraph { |
|
const AVClass *av_class; |
|
#if FF_API_FOO_COUNT |
|
attribute_deprecated |
|
unsigned filter_count_unused; |
|
#endif |
|
AVFilterContext **filters; |
|
#if !FF_API_FOO_COUNT |
|
unsigned nb_filters; |
|
#endif |
|
|
|
char *scale_sws_opts; ///< sws options to use for the auto-inserted scale filters |
|
char *resample_lavr_opts; ///< libavresample options to use for the auto-inserted resample filters |
|
#if FF_API_FOO_COUNT |
|
unsigned nb_filters; |
|
#endif |
|
char *aresample_swr_opts; ///< swr options to use for the auto-inserted aresample filters, Access ONLY through AVOptions |
|
|
|
/** |
|
* Private fields |
|
* |
|
* The following fields are for internal use only. |
|
* Their type, offset, number and semantic can change without notice. |
|
*/ |
|
|
|
AVFilterLink **sink_links; |
|
int sink_links_count; |
|
|
|
unsigned disable_auto_convert; |
|
} AVFilterGraph; |
|
|
|
/** |
|
* Allocate a filter graph. |
|
*/ |
|
AVFilterGraph *avfilter_graph_alloc(void); |
|
|
|
/** |
|
* Create a new filter instance in a filter graph. |
|
* |
|
* @param graph graph in which the new filter will be used |
|
* @param filter the filter to create an instance of |
|
* @param name Name to give to the new instance (will be copied to |
|
* AVFilterContext.name). This may be used by the caller to identify |
|
* different filters, libavfilter itself assigns no semantics to |
|
* this parameter. May be NULL. |
|
* |
|
* @return the context of the newly created filter instance (note that it is |
|
* also retrievable directly through AVFilterGraph.filters or with |
|
* avfilter_graph_get_filter()) on success or NULL or failure. |
|
*/ |
|
AVFilterContext *avfilter_graph_alloc_filter(AVFilterGraph *graph, |
|
const AVFilter *filter, |
|
const char *name); |
|
|
|
/** |
|
* Get a filter instance with name name from graph. |
|
* |
|
* @return the pointer to the found filter instance or NULL if it |
|
* cannot be found. |
|
*/ |
|
AVFilterContext *avfilter_graph_get_filter(AVFilterGraph *graph, char *name); |
|
|
|
#if FF_API_AVFILTER_OPEN |
|
/** |
|
* Add an existing filter instance to a filter graph. |
|
* |
|
* @param graphctx the filter graph |
|
* @param filter the filter to be added |
|
* |
|
* @deprecated use avfilter_graph_alloc_filter() to allocate a filter in a |
|
* filter graph |
|
*/ |
|
attribute_deprecated |
|
int avfilter_graph_add_filter(AVFilterGraph *graphctx, AVFilterContext *filter); |
|
#endif |
|
|
|
/** |
|
* Create and add a filter instance into an existing graph. |
|
* The filter instance is created from the filter filt and inited |
|
* with the parameters args and opaque. |
|
* |
|
* In case of success put in *filt_ctx the pointer to the created |
|
* filter instance, otherwise set *filt_ctx to NULL. |
|
* |
|
* @param name the instance name to give to the created filter instance |
|
* @param graph_ctx the filter graph |
|
* @return a negative AVERROR error code in case of failure, a non |
|
* negative value otherwise |
|
*/ |
|
int avfilter_graph_create_filter(AVFilterContext **filt_ctx, AVFilter *filt, |
|
const char *name, const char *args, void *opaque, |
|
AVFilterGraph *graph_ctx); |
|
|
|
/** |
|
* Enable or disable automatic format conversion inside the graph. |
|
* |
|
* Note that format conversion can still happen inside explicitly inserted |
|
* scale and aresample filters. |
|
* |
|
* @param flags any of the AVFILTER_AUTO_CONVERT_* constants |
|
*/ |
|
void avfilter_graph_set_auto_convert(AVFilterGraph *graph, unsigned flags); |
|
|
|
enum { |
|
AVFILTER_AUTO_CONVERT_ALL = 0, /**< all automatic conversions enabled */ |
|
AVFILTER_AUTO_CONVERT_NONE = -1, /**< all automatic conversions disabled */ |
|
}; |
|
|
|
/** |
|
* Check validity and configure all the links and formats in the graph. |
|
* |
|
* @param graphctx the filter graph |
|
* @param log_ctx context used for logging |
|
* @return 0 in case of success, a negative AVERROR code otherwise |
|
*/ |
|
int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx); |
|
|
|
/** |
|
* Free a graph, destroy its links, and set *graph to NULL. |
|
* If *graph is NULL, do nothing. |
|
*/ |
|
void avfilter_graph_free(AVFilterGraph **graph); |
|
|
|
/** |
|
* A linked-list of the inputs/outputs of the filter chain. |
|
* |
|
* This is mainly useful for avfilter_graph_parse() / avfilter_graph_parse2(), |
|
* where it is used to communicate open (unlinked) inputs and outputs from and |
|
* to the caller. |
|
* This struct specifies, per each not connected pad contained in the graph, the |
|
* filter context and the pad index required for establishing a link. |
|
*/ |
|
typedef struct AVFilterInOut { |
|
/** unique name for this input/output in the list */ |
|
char *name; |
|
|
|
/** filter context associated to this input/output */ |
|
AVFilterContext *filter_ctx; |
|
|
|
/** index of the filt_ctx pad to use for linking */ |
|
int pad_idx; |
|
|
|
/** next input/input in the list, NULL if this is the last */ |
|
struct AVFilterInOut *next; |
|
} AVFilterInOut; |
|
|
|
/** |
|
* Allocate a single AVFilterInOut entry. |
|
* Must be freed with avfilter_inout_free(). |
|
* @return allocated AVFilterInOut on success, NULL on failure. |
|
*/ |
|
AVFilterInOut *avfilter_inout_alloc(void); |
|
|
|
/** |
|
* Free the supplied list of AVFilterInOut and set *inout to NULL. |
|
* If *inout is NULL, do nothing. |
|
*/ |
|
void avfilter_inout_free(AVFilterInOut **inout); |
|
|
|
/** |
|
* Add a graph described by a string to a graph. |
|
* |
|
* @param graph the filter graph where to link the parsed graph context |
|
* @param filters string to be parsed |
|
* @param inputs pointer to a linked list to the inputs of the graph, may be NULL. |
|
* If non-NULL, *inputs is updated to contain the list of open inputs |
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* after the parsing, should be freed with avfilter_inout_free(). |
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* @param outputs pointer to a linked list to the outputs of the graph, may be NULL. |
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* If non-NULL, *outputs is updated to contain the list of open outputs |
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* after the parsing, should be freed with avfilter_inout_free(). |
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* @return non negative on success, a negative AVERROR code on error |
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*/ |
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int avfilter_graph_parse(AVFilterGraph *graph, const char *filters, |
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AVFilterInOut **inputs, AVFilterInOut **outputs, |
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void *log_ctx); |
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|
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/** |
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* Add a graph described by a string to a graph. |
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* |
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* @param[in] graph the filter graph where to link the parsed graph context |
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* @param[in] filters string to be parsed |
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* @param[out] inputs a linked list of all free (unlinked) inputs of the |
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* parsed graph will be returned here. It is to be freed |
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* by the caller using avfilter_inout_free(). |
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* @param[out] outputs a linked list of all free (unlinked) outputs of the |
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* parsed graph will be returned here. It is to be freed by the |
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* caller using avfilter_inout_free(). |
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* @return zero on success, a negative AVERROR code on error |
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* |
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* @note the difference between avfilter_graph_parse2() and |
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* avfilter_graph_parse() is that in avfilter_graph_parse(), the caller provides |
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* the lists of inputs and outputs, which therefore must be known before calling |
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* the function. On the other hand, avfilter_graph_parse2() \em returns the |
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* inputs and outputs that are left unlinked after parsing the graph and the |
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* caller then deals with them. Another difference is that in |
|
* avfilter_graph_parse(), the inputs parameter describes inputs of the |
|
* <em>already existing</em> part of the graph; i.e. from the point of view of |
|
* the newly created part, they are outputs. Similarly the outputs parameter |
|
* describes outputs of the already existing filters, which are provided as |
|
* inputs to the parsed filters. |
|
* avfilter_graph_parse2() takes the opposite approach -- it makes no reference |
|
* whatsoever to already existing parts of the graph and the inputs parameter |
|
* will on return contain inputs of the newly parsed part of the graph. |
|
* Analogously the outputs parameter will contain outputs of the newly created |
|
* filters. |
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*/ |
|
int avfilter_graph_parse2(AVFilterGraph *graph, const char *filters, |
|
AVFilterInOut **inputs, |
|
AVFilterInOut **outputs); |
|
|
|
/** |
|
* Send a command to one or more filter instances. |
|
* |
|
* @param graph the filter graph |
|
* @param target the filter(s) to which the command should be sent |
|
* "all" sends to all filters |
|
* otherwise it can be a filter or filter instance name |
|
* which will send the command to all matching filters. |
|
* @param cmd the command to send, for handling simplicity all commands must be alphanumeric only |
|
* @param arg the argument for the command |
|
* @param res a buffer with size res_size where the filter(s) can return a response. |
|
* |
|
* @returns >=0 on success otherwise an error code. |
|
* AVERROR(ENOSYS) on unsupported commands |
|
*/ |
|
int avfilter_graph_send_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, char *res, int res_len, int flags); |
|
|
|
/** |
|
* Queue a command for one or more filter instances. |
|
* |
|
* @param graph the filter graph |
|
* @param target the filter(s) to which the command should be sent |
|
* "all" sends to all filters |
|
* otherwise it can be a filter or filter instance name |
|
* which will send the command to all matching filters. |
|
* @param cmd the command to sent, for handling simplicity all commands must be alphanummeric only |
|
* @param arg the argument for the command |
|
* @param ts time at which the command should be sent to the filter |
|
* |
|
* @note As this executes commands after this function returns, no return code |
|
* from the filter is provided, also AVFILTER_CMD_FLAG_ONE is not supported. |
|
*/ |
|
int avfilter_graph_queue_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, int flags, double ts); |
|
|
|
|
|
/** |
|
* Dump a graph into a human-readable string representation. |
|
* |
|
* @param graph the graph to dump |
|
* @param options formatting options; currently ignored |
|
* @return a string, or NULL in case of memory allocation failure; |
|
* the string must be freed using av_free |
|
*/ |
|
char *avfilter_graph_dump(AVFilterGraph *graph, const char *options); |
|
|
|
/** |
|
* Request a frame on the oldest sink link. |
|
* |
|
* If the request returns AVERROR_EOF, try the next. |
|
* |
|
* Note that this function is not meant to be the sole scheduling mechanism |
|
* of a filtergraph, only a convenience function to help drain a filtergraph |
|
* in a balanced way under normal circumstances. |
|
* |
|
* Also note that AVERROR_EOF does not mean that frames did not arrive on |
|
* some of the sinks during the process. |
|
* When there are multiple sink links, in case the requested link |
|
* returns an EOF, this may cause a filter to flush pending frames |
|
* which are sent to another sink link, although unrequested. |
|
* |
|
* @return the return value of ff_request_frame(), |
|
* or AVERROR_EOF if all links returned AVERROR_EOF |
|
*/ |
|
int avfilter_graph_request_oldest(AVFilterGraph *graph); |
|
|
|
/** |
|
* @} |
|
*/ |
|
#endif /* AVFILTER_AVFILTER_H */
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