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1809 lines
56 KiB
1809 lines
56 KiB
/* |
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* MPEG1/2 mux/demux |
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* Copyright (c) 2000, 2001, 2002 Fabrice Bellard. |
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* |
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* This library 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 of the License, or (at your option) any later version. |
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* |
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* This library 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 this library; 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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#include "avformat.h" |
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#include "bitstream.h" |
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|
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#define MAX_PAYLOAD_SIZE 4096 |
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//#define DEBUG_SEEK |
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|
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#undef NDEBUG |
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#include <assert.h> |
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|
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typedef struct PacketDesc { |
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int64_t pts; |
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int64_t dts; |
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int size; |
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int unwritten_size; |
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int flags; |
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struct PacketDesc *next; |
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} PacketDesc; |
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|
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typedef struct { |
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FifoBuffer fifo; |
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uint8_t id; |
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int max_buffer_size; /* in bytes */ |
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int buffer_index; |
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PacketDesc *predecode_packet; |
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PacketDesc *premux_packet; |
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PacketDesc **next_packet; |
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int packet_number; |
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uint8_t lpcm_header[3]; |
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int lpcm_align; |
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uint8_t *fifo_iframe_ptr; |
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int align_iframe; |
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int64_t vobu_start_pts; |
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} StreamInfo; |
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|
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typedef struct { |
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int packet_size; /* required packet size */ |
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int packet_number; |
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int pack_header_freq; /* frequency (in packets^-1) at which we send pack headers */ |
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int system_header_freq; |
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int system_header_size; |
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int mux_rate; /* bitrate in units of 50 bytes/s */ |
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/* stream info */ |
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int audio_bound; |
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int video_bound; |
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int is_mpeg2; |
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int is_vcd; |
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int is_svcd; |
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int is_dvd; |
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int64_t last_scr; /* current system clock */ |
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|
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double vcd_padding_bitrate; //FIXME floats |
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int64_t vcd_padding_bytes_written; |
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|
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} MpegMuxContext; |
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|
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#define PACK_START_CODE ((unsigned int)0x000001ba) |
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#define SYSTEM_HEADER_START_CODE ((unsigned int)0x000001bb) |
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#define SEQUENCE_END_CODE ((unsigned int)0x000001b7) |
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#define PACKET_START_CODE_MASK ((unsigned int)0xffffff00) |
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#define PACKET_START_CODE_PREFIX ((unsigned int)0x00000100) |
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#define ISO_11172_END_CODE ((unsigned int)0x000001b9) |
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|
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/* mpeg2 */ |
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#define PROGRAM_STREAM_MAP 0x1bc |
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#define PRIVATE_STREAM_1 0x1bd |
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#define PADDING_STREAM 0x1be |
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#define PRIVATE_STREAM_2 0x1bf |
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|
|
|
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#define AUDIO_ID 0xc0 |
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#define VIDEO_ID 0xe0 |
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#define AC3_ID 0x80 |
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#define DTS_ID 0x8a |
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#define LPCM_ID 0xa0 |
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#define SUB_ID 0x20 |
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|
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#define STREAM_TYPE_VIDEO_MPEG1 0x01 |
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#define STREAM_TYPE_VIDEO_MPEG2 0x02 |
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#define STREAM_TYPE_AUDIO_MPEG1 0x03 |
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#define STREAM_TYPE_AUDIO_MPEG2 0x04 |
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#define STREAM_TYPE_PRIVATE_SECTION 0x05 |
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#define STREAM_TYPE_PRIVATE_DATA 0x06 |
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#define STREAM_TYPE_AUDIO_AAC 0x0f |
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#define STREAM_TYPE_VIDEO_MPEG4 0x10 |
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#define STREAM_TYPE_VIDEO_H264 0x1b |
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|
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#define STREAM_TYPE_AUDIO_AC3 0x81 |
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#define STREAM_TYPE_AUDIO_DTS 0x8a |
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|
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static const int lpcm_freq_tab[4] = { 48000, 96000, 44100, 32000 }; |
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|
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#ifdef CONFIG_MUXERS |
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static AVOutputFormat mpeg1system_mux; |
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static AVOutputFormat mpeg1vcd_mux; |
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static AVOutputFormat mpeg2vob_mux; |
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static AVOutputFormat mpeg2svcd_mux; |
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static AVOutputFormat mpeg2dvd_mux; |
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|
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static int put_pack_header(AVFormatContext *ctx, |
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uint8_t *buf, int64_t timestamp) |
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{ |
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MpegMuxContext *s = ctx->priv_data; |
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PutBitContext pb; |
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|
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init_put_bits(&pb, buf, 128); |
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|
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put_bits(&pb, 32, PACK_START_CODE); |
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if (s->is_mpeg2) { |
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put_bits(&pb, 2, 0x1); |
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} else { |
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put_bits(&pb, 4, 0x2); |
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} |
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put_bits(&pb, 3, (uint32_t)((timestamp >> 30) & 0x07)); |
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put_bits(&pb, 1, 1); |
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put_bits(&pb, 15, (uint32_t)((timestamp >> 15) & 0x7fff)); |
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put_bits(&pb, 1, 1); |
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put_bits(&pb, 15, (uint32_t)((timestamp) & 0x7fff)); |
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put_bits(&pb, 1, 1); |
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if (s->is_mpeg2) { |
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/* clock extension */ |
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put_bits(&pb, 9, 0); |
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} |
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put_bits(&pb, 1, 1); |
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put_bits(&pb, 22, s->mux_rate); |
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put_bits(&pb, 1, 1); |
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if (s->is_mpeg2) { |
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put_bits(&pb, 1, 1); |
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put_bits(&pb, 5, 0x1f); /* reserved */ |
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put_bits(&pb, 3, 0); /* stuffing length */ |
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} |
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flush_put_bits(&pb); |
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return pbBufPtr(&pb) - pb.buf; |
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} |
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|
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static int put_system_header(AVFormatContext *ctx, uint8_t *buf,int only_for_stream_id) |
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{ |
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MpegMuxContext *s = ctx->priv_data; |
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int size, i, private_stream_coded, id; |
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PutBitContext pb; |
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|
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init_put_bits(&pb, buf, 128); |
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|
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put_bits(&pb, 32, SYSTEM_HEADER_START_CODE); |
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put_bits(&pb, 16, 0); |
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put_bits(&pb, 1, 1); |
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|
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put_bits(&pb, 22, s->mux_rate); /* maximum bit rate of the multiplexed stream */ |
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put_bits(&pb, 1, 1); /* marker */ |
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if (s->is_vcd && only_for_stream_id==VIDEO_ID) { |
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/* This header applies only to the video stream (see VCD standard p. IV-7)*/ |
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put_bits(&pb, 6, 0); |
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} else |
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put_bits(&pb, 6, s->audio_bound); |
|
|
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if (s->is_vcd) { |
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/* see VCD standard, p. IV-7*/ |
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put_bits(&pb, 1, 0); |
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put_bits(&pb, 1, 1); |
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} else { |
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put_bits(&pb, 1, 0); /* variable bitrate*/ |
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put_bits(&pb, 1, 0); /* non constrainted bit stream */ |
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} |
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|
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if (s->is_vcd || s->is_dvd) { |
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/* see VCD standard p IV-7 */ |
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put_bits(&pb, 1, 1); /* audio locked */ |
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put_bits(&pb, 1, 1); /* video locked */ |
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} else { |
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put_bits(&pb, 1, 0); /* audio locked */ |
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put_bits(&pb, 1, 0); /* video locked */ |
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} |
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|
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put_bits(&pb, 1, 1); /* marker */ |
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|
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if (s->is_vcd && only_for_stream_id==AUDIO_ID) { |
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/* This header applies only to the audio stream (see VCD standard p. IV-7)*/ |
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put_bits(&pb, 5, 0); |
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} else |
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put_bits(&pb, 5, s->video_bound); |
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|
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if (s->is_dvd) { |
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put_bits(&pb, 1, 0); /* packet_rate_restriction_flag */ |
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put_bits(&pb, 7, 0x7f); /* reserved byte */ |
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} else |
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put_bits(&pb, 8, 0xff); /* reserved byte */ |
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|
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/* DVD-Video Stream_bound entries |
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id (0xB9) video, maximum P-STD for stream 0xE0. (P-STD_buffer_bound_scale = 1) |
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id (0xB8) audio, maximum P-STD for any MPEG audio (0xC0 to 0xC7) streams. If there are none set to 4096 (32x128). (P-STD_buffer_bound_scale = 0) |
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id (0xBD) private stream 1 (audio other than MPEG and subpictures). (P-STD_buffer_bound_scale = 1) |
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id (0xBF) private stream 2, NAV packs, set to 2x1024. */ |
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if (s->is_dvd) { |
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|
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int P_STD_max_video = 0; |
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int P_STD_max_mpeg_audio = 0; |
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int P_STD_max_mpeg_PS1 = 0; |
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|
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for(i=0;i<ctx->nb_streams;i++) { |
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StreamInfo *stream = ctx->streams[i]->priv_data; |
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|
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id = stream->id; |
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if (id == 0xbd && stream->max_buffer_size > P_STD_max_mpeg_PS1) { |
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P_STD_max_mpeg_PS1 = stream->max_buffer_size; |
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} else if (id >= 0xc0 && id <= 0xc7 && stream->max_buffer_size > P_STD_max_mpeg_audio) { |
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P_STD_max_mpeg_audio = stream->max_buffer_size; |
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} else if (id == 0xe0 && stream->max_buffer_size > P_STD_max_video) { |
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P_STD_max_video = stream->max_buffer_size; |
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} |
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} |
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|
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/* video */ |
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put_bits(&pb, 8, 0xb9); /* stream ID */ |
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put_bits(&pb, 2, 3); |
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put_bits(&pb, 1, 1); |
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put_bits(&pb, 13, P_STD_max_video / 1024); |
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|
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/* audio */ |
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if (P_STD_max_mpeg_audio == 0) |
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P_STD_max_mpeg_audio = 4096; |
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put_bits(&pb, 8, 0xb8); /* stream ID */ |
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put_bits(&pb, 2, 3); |
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put_bits(&pb, 1, 0); |
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put_bits(&pb, 13, P_STD_max_mpeg_audio / 128); |
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|
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/* private stream 1 */ |
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put_bits(&pb, 8, 0xbd); /* stream ID */ |
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put_bits(&pb, 2, 3); |
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put_bits(&pb, 1, 0); |
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put_bits(&pb, 13, P_STD_max_mpeg_PS1 / 128); |
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|
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/* private stream 2 */ |
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put_bits(&pb, 8, 0xbf); /* stream ID */ |
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put_bits(&pb, 2, 3); |
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put_bits(&pb, 1, 1); |
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put_bits(&pb, 13, 2); |
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} |
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else { |
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/* audio stream info */ |
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private_stream_coded = 0; |
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for(i=0;i<ctx->nb_streams;i++) { |
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StreamInfo *stream = ctx->streams[i]->priv_data; |
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|
|
|
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/* For VCDs, only include the stream info for the stream |
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that the pack which contains this system belongs to. |
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(see VCD standard p. IV-7) */ |
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if ( !s->is_vcd || stream->id==only_for_stream_id |
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|| only_for_stream_id==0) { |
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|
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id = stream->id; |
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if (id < 0xc0) { |
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/* special case for private streams (AC3 use that) */ |
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if (private_stream_coded) |
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continue; |
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private_stream_coded = 1; |
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id = 0xbd; |
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} |
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put_bits(&pb, 8, id); /* stream ID */ |
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put_bits(&pb, 2, 3); |
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if (id < 0xe0) { |
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/* audio */ |
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put_bits(&pb, 1, 0); |
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put_bits(&pb, 13, stream->max_buffer_size / 128); |
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} else { |
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/* video */ |
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put_bits(&pb, 1, 1); |
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put_bits(&pb, 13, stream->max_buffer_size / 1024); |
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} |
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} |
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} |
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} |
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|
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flush_put_bits(&pb); |
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size = pbBufPtr(&pb) - pb.buf; |
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/* patch packet size */ |
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buf[4] = (size - 6) >> 8; |
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buf[5] = (size - 6) & 0xff; |
|
|
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return size; |
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} |
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|
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static int get_system_header_size(AVFormatContext *ctx) |
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{ |
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int buf_index, i, private_stream_coded; |
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StreamInfo *stream; |
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MpegMuxContext *s = ctx->priv_data; |
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|
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if (s->is_dvd) |
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return 18; // DVD-Video system headers are 18 bytes fixed length. |
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|
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buf_index = 12; |
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private_stream_coded = 0; |
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for(i=0;i<ctx->nb_streams;i++) { |
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stream = ctx->streams[i]->priv_data; |
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if (stream->id < 0xc0) { |
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if (private_stream_coded) |
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continue; |
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private_stream_coded = 1; |
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} |
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buf_index += 3; |
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} |
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return buf_index; |
|
} |
|
|
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static int mpeg_mux_init(AVFormatContext *ctx) |
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{ |
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MpegMuxContext *s = ctx->priv_data; |
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int bitrate, i, mpa_id, mpv_id, mps_id, ac3_id, dts_id, lpcm_id, j; |
|
AVStream *st; |
|
StreamInfo *stream; |
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int audio_bitrate; |
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int video_bitrate; |
|
|
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s->packet_number = 0; |
|
s->is_vcd = (ctx->oformat == &mpeg1vcd_mux); |
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s->is_svcd = (ctx->oformat == &mpeg2svcd_mux); |
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s->is_mpeg2 = (ctx->oformat == &mpeg2vob_mux || ctx->oformat == &mpeg2svcd_mux || ctx->oformat == &mpeg2dvd_mux); |
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s->is_dvd = (ctx->oformat == &mpeg2dvd_mux); |
|
|
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if(ctx->packet_size) |
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s->packet_size = ctx->packet_size; |
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else |
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s->packet_size = 2048; |
|
|
|
s->vcd_padding_bytes_written = 0; |
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s->vcd_padding_bitrate=0; |
|
|
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s->audio_bound = 0; |
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s->video_bound = 0; |
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mpa_id = AUDIO_ID; |
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ac3_id = AC3_ID; |
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dts_id = DTS_ID; |
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mpv_id = VIDEO_ID; |
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mps_id = SUB_ID; |
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lpcm_id = LPCM_ID; |
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for(i=0;i<ctx->nb_streams;i++) { |
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st = ctx->streams[i]; |
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stream = av_mallocz(sizeof(StreamInfo)); |
|
if (!stream) |
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goto fail; |
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st->priv_data = stream; |
|
|
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av_set_pts_info(st, 64, 1, 90000); |
|
|
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switch(st->codec->codec_type) { |
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case CODEC_TYPE_AUDIO: |
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if (st->codec->codec_id == CODEC_ID_AC3) { |
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stream->id = ac3_id++; |
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} else if (st->codec->codec_id == CODEC_ID_DTS) { |
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stream->id = dts_id++; |
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} else if (st->codec->codec_id == CODEC_ID_PCM_S16BE) { |
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stream->id = lpcm_id++; |
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for(j = 0; j < 4; j++) { |
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if (lpcm_freq_tab[j] == st->codec->sample_rate) |
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break; |
|
} |
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if (j == 4) |
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goto fail; |
|
if (st->codec->channels > 8) |
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return -1; |
|
stream->lpcm_header[0] = 0x0c; |
|
stream->lpcm_header[1] = (st->codec->channels - 1) | (j << 4); |
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stream->lpcm_header[2] = 0x80; |
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stream->lpcm_align = st->codec->channels * 2; |
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} else { |
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stream->id = mpa_id++; |
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} |
|
|
|
/* This value HAS to be used for VCD (see VCD standard, p. IV-7). |
|
Right now it is also used for everything else.*/ |
|
stream->max_buffer_size = 4 * 1024; |
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s->audio_bound++; |
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break; |
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case CODEC_TYPE_VIDEO: |
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stream->id = mpv_id++; |
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if (st->codec->rc_buffer_size) |
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stream->max_buffer_size = 6*1024 + st->codec->rc_buffer_size/8; |
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else |
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stream->max_buffer_size = 230*1024; //FIXME this is probably too small as default |
|
#if 0 |
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/* see VCD standard, p. IV-7*/ |
|
stream->max_buffer_size = 46 * 1024; |
|
else |
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/* This value HAS to be used for SVCD (see SVCD standard, p. 26 V.2.3.2). |
|
Right now it is also used for everything else.*/ |
|
stream->max_buffer_size = 230 * 1024; |
|
#endif |
|
s->video_bound++; |
|
break; |
|
case CODEC_TYPE_SUBTITLE: |
|
stream->id = mps_id++; |
|
stream->max_buffer_size = 16 * 1024; |
|
break; |
|
default: |
|
return -1; |
|
} |
|
fifo_init(&stream->fifo, 16); |
|
} |
|
bitrate = 0; |
|
audio_bitrate = 0; |
|
video_bitrate = 0; |
|
for(i=0;i<ctx->nb_streams;i++) { |
|
int codec_rate; |
|
st = ctx->streams[i]; |
|
stream = (StreamInfo*) st->priv_data; |
|
|
|
if(st->codec->rc_max_rate || stream->id==VIDEO_ID) |
|
codec_rate= st->codec->rc_max_rate; |
|
else |
|
codec_rate= st->codec->bit_rate; |
|
|
|
if(!codec_rate) |
|
codec_rate= (1<<21)*8*50/ctx->nb_streams; |
|
|
|
bitrate += codec_rate; |
|
|
|
if (stream->id==AUDIO_ID) |
|
audio_bitrate += codec_rate; |
|
else if (stream->id==VIDEO_ID) |
|
video_bitrate += codec_rate; |
|
} |
|
|
|
if(ctx->mux_rate){ |
|
s->mux_rate= (ctx->mux_rate + (8 * 50) - 1) / (8 * 50); |
|
} else { |
|
/* we increase slightly the bitrate to take into account the |
|
headers. XXX: compute it exactly */ |
|
bitrate += bitrate*5/100; |
|
bitrate += 10000; |
|
s->mux_rate = (bitrate + (8 * 50) - 1) / (8 * 50); |
|
} |
|
|
|
if (s->is_vcd) { |
|
double overhead_rate; |
|
|
|
/* The VCD standard mandates that the mux_rate field is 3528 |
|
(see standard p. IV-6). |
|
The value is actually "wrong", i.e. if you calculate |
|
it using the normal formula and the 75 sectors per second transfer |
|
rate you get a different value because the real pack size is 2324, |
|
not 2352. But the standard explicitly specifies that the mux_rate |
|
field in the header must have this value.*/ |
|
// s->mux_rate=2352 * 75 / 50; /* = 3528*/ |
|
|
|
/* The VCD standard states that the muxed stream must be |
|
exactly 75 packs / second (the data rate of a single speed cdrom). |
|
Since the video bitrate (probably 1150000 bits/sec) will be below |
|
the theoretical maximum we have to add some padding packets |
|
to make up for the lower data rate. |
|
(cf. VCD standard p. IV-6 )*/ |
|
|
|
/* Add the header overhead to the data rate. |
|
2279 data bytes per audio pack, 2294 data bytes per video pack*/ |
|
overhead_rate = ((audio_bitrate / 8.0) / 2279) * (2324 - 2279); |
|
overhead_rate += ((video_bitrate / 8.0) / 2294) * (2324 - 2294); |
|
overhead_rate *= 8; |
|
|
|
/* Add padding so that the full bitrate is 2324*75 bytes/sec */ |
|
s->vcd_padding_bitrate = 2324 * 75 * 8 - (bitrate + overhead_rate); |
|
} |
|
|
|
if (s->is_vcd || s->is_mpeg2) |
|
/* every packet */ |
|
s->pack_header_freq = 1; |
|
else |
|
/* every 2 seconds */ |
|
s->pack_header_freq = 2 * bitrate / s->packet_size / 8; |
|
|
|
/* the above seems to make pack_header_freq zero sometimes */ |
|
if (s->pack_header_freq == 0) |
|
s->pack_header_freq = 1; |
|
|
|
if (s->is_mpeg2) |
|
/* every 200 packets. Need to look at the spec. */ |
|
s->system_header_freq = s->pack_header_freq * 40; |
|
else if (s->is_vcd) |
|
/* the standard mandates that there are only two system headers |
|
in the whole file: one in the first packet of each stream. |
|
(see standard p. IV-7 and IV-8) */ |
|
s->system_header_freq = 0x7fffffff; |
|
else |
|
s->system_header_freq = s->pack_header_freq * 5; |
|
|
|
for(i=0;i<ctx->nb_streams;i++) { |
|
stream = ctx->streams[i]->priv_data; |
|
stream->packet_number = 0; |
|
} |
|
s->system_header_size = get_system_header_size(ctx); |
|
s->last_scr = 0; |
|
return 0; |
|
fail: |
|
for(i=0;i<ctx->nb_streams;i++) { |
|
av_free(ctx->streams[i]->priv_data); |
|
} |
|
return -ENOMEM; |
|
} |
|
|
|
static inline void put_timestamp(ByteIOContext *pb, int id, int64_t timestamp) |
|
{ |
|
put_byte(pb, |
|
(id << 4) | |
|
(((timestamp >> 30) & 0x07) << 1) | |
|
1); |
|
put_be16(pb, (uint16_t)((((timestamp >> 15) & 0x7fff) << 1) | 1)); |
|
put_be16(pb, (uint16_t)((((timestamp) & 0x7fff) << 1) | 1)); |
|
} |
|
|
|
|
|
/* return the number of padding bytes that should be inserted into |
|
the multiplexed stream.*/ |
|
static int get_vcd_padding_size(AVFormatContext *ctx, int64_t pts) |
|
{ |
|
MpegMuxContext *s = ctx->priv_data; |
|
int pad_bytes = 0; |
|
|
|
if (s->vcd_padding_bitrate > 0 && pts!=AV_NOPTS_VALUE) |
|
{ |
|
int64_t full_pad_bytes; |
|
|
|
full_pad_bytes = (int64_t)((s->vcd_padding_bitrate * (pts / 90000.0)) / 8.0); //FIXME this is wrong |
|
pad_bytes = (int) (full_pad_bytes - s->vcd_padding_bytes_written); |
|
|
|
if (pad_bytes<0) |
|
/* might happen if we have already padded to a later timestamp. This |
|
can occur if another stream has already advanced further.*/ |
|
pad_bytes=0; |
|
} |
|
|
|
return pad_bytes; |
|
} |
|
|
|
|
|
#if 0 /* unused, remove? */ |
|
/* return the exact available payload size for the next packet for |
|
stream 'stream_index'. 'pts' and 'dts' are only used to know if |
|
timestamps are needed in the packet header. */ |
|
static int get_packet_payload_size(AVFormatContext *ctx, int stream_index, |
|
int64_t pts, int64_t dts) |
|
{ |
|
MpegMuxContext *s = ctx->priv_data; |
|
int buf_index; |
|
StreamInfo *stream; |
|
|
|
stream = ctx->streams[stream_index]->priv_data; |
|
|
|
buf_index = 0; |
|
if (((s->packet_number % s->pack_header_freq) == 0)) { |
|
/* pack header size */ |
|
if (s->is_mpeg2) |
|
buf_index += 14; |
|
else |
|
buf_index += 12; |
|
|
|
if (s->is_vcd) { |
|
/* there is exactly one system header for each stream in a VCD MPEG, |
|
One in the very first video packet and one in the very first |
|
audio packet (see VCD standard p. IV-7 and IV-8).*/ |
|
|
|
if (stream->packet_number==0) |
|
/* The system headers refer only to the stream they occur in, |
|
so they have a constant size.*/ |
|
buf_index += 15; |
|
|
|
} else { |
|
if ((s->packet_number % s->system_header_freq) == 0) |
|
buf_index += s->system_header_size; |
|
} |
|
} |
|
|
|
if ((s->is_vcd && stream->packet_number==0) |
|
|| (s->is_svcd && s->packet_number==0)) |
|
/* the first pack of each stream contains only the pack header, |
|
the system header and some padding (see VCD standard p. IV-6) |
|
Add the padding size, so that the actual payload becomes 0.*/ |
|
buf_index += s->packet_size - buf_index; |
|
else { |
|
/* packet header size */ |
|
buf_index += 6; |
|
if (s->is_mpeg2) { |
|
buf_index += 3; |
|
if (stream->packet_number==0) |
|
buf_index += 3; /* PES extension */ |
|
buf_index += 1; /* obligatory stuffing byte */ |
|
} |
|
if (pts != AV_NOPTS_VALUE) { |
|
if (dts != pts) |
|
buf_index += 5 + 5; |
|
else |
|
buf_index += 5; |
|
|
|
} else { |
|
if (!s->is_mpeg2) |
|
buf_index++; |
|
} |
|
|
|
if (stream->id < 0xc0) { |
|
/* AC3/LPCM private data header */ |
|
buf_index += 4; |
|
if (stream->id >= 0xa0) { |
|
int n; |
|
buf_index += 3; |
|
/* NOTE: we round the payload size to an integer number of |
|
LPCM samples */ |
|
n = (s->packet_size - buf_index) % stream->lpcm_align; |
|
if (n) |
|
buf_index += (stream->lpcm_align - n); |
|
} |
|
} |
|
|
|
if (s->is_vcd && stream->id == AUDIO_ID) |
|
/* The VCD standard demands that 20 zero bytes follow |
|
each audio packet (see standard p. IV-8).*/ |
|
buf_index+=20; |
|
} |
|
return s->packet_size - buf_index; |
|
} |
|
#endif |
|
|
|
/* Write an MPEG padding packet header. */ |
|
static void put_padding_packet(AVFormatContext *ctx, ByteIOContext *pb,int packet_bytes) |
|
{ |
|
MpegMuxContext *s = ctx->priv_data; |
|
int i; |
|
|
|
put_be32(pb, PADDING_STREAM); |
|
put_be16(pb, packet_bytes - 6); |
|
if (!s->is_mpeg2) { |
|
put_byte(pb, 0x0f); |
|
packet_bytes -= 7; |
|
} else |
|
packet_bytes -= 6; |
|
|
|
for(i=0;i<packet_bytes;i++) |
|
put_byte(pb, 0xff); |
|
} |
|
|
|
static int get_nb_frames(AVFormatContext *ctx, StreamInfo *stream, int len){ |
|
int nb_frames=0; |
|
PacketDesc *pkt_desc= stream->premux_packet; |
|
|
|
while(len>0){ |
|
if(pkt_desc->size == pkt_desc->unwritten_size) |
|
nb_frames++; |
|
len -= pkt_desc->unwritten_size; |
|
pkt_desc= pkt_desc->next; |
|
} |
|
|
|
return nb_frames; |
|
} |
|
|
|
/* flush the packet on stream stream_index */ |
|
static int flush_packet(AVFormatContext *ctx, int stream_index, |
|
int64_t pts, int64_t dts, int64_t scr, int trailer_size) |
|
{ |
|
MpegMuxContext *s = ctx->priv_data; |
|
StreamInfo *stream = ctx->streams[stream_index]->priv_data; |
|
uint8_t *buf_ptr; |
|
int size, payload_size, startcode, id, stuffing_size, i, header_len; |
|
int packet_size; |
|
uint8_t buffer[128]; |
|
int zero_trail_bytes = 0; |
|
int pad_packet_bytes = 0; |
|
int pes_flags; |
|
int general_pack = 0; /*"general" pack without data specific to one stream?*/ |
|
int nb_frames; |
|
|
|
id = stream->id; |
|
|
|
#if 0 |
|
printf("packet ID=%2x PTS=%0.3f\n", |
|
id, pts / 90000.0); |
|
#endif |
|
|
|
buf_ptr = buffer; |
|
|
|
if ((s->packet_number % s->pack_header_freq) == 0 || s->last_scr != scr) { |
|
/* output pack and systems header if needed */ |
|
size = put_pack_header(ctx, buf_ptr, scr); |
|
buf_ptr += size; |
|
s->last_scr= scr; |
|
|
|
if (s->is_vcd) { |
|
/* there is exactly one system header for each stream in a VCD MPEG, |
|
One in the very first video packet and one in the very first |
|
audio packet (see VCD standard p. IV-7 and IV-8).*/ |
|
|
|
if (stream->packet_number==0) { |
|
size = put_system_header(ctx, buf_ptr, id); |
|
buf_ptr += size; |
|
} |
|
} else if (s->is_dvd) { |
|
if (stream->align_iframe || s->packet_number == 0){ |
|
int bytes_to_iframe; |
|
int PES_bytes_to_fill; |
|
if (stream->fifo_iframe_ptr >= stream->fifo.rptr) { |
|
bytes_to_iframe = stream->fifo_iframe_ptr - stream->fifo.rptr; |
|
} else { |
|
bytes_to_iframe = (stream->fifo.end - stream->fifo.rptr) + (stream->fifo_iframe_ptr - stream->fifo.buffer); |
|
} |
|
PES_bytes_to_fill = s->packet_size - size - 10; |
|
|
|
if (pts != AV_NOPTS_VALUE) { |
|
if (dts != pts) |
|
PES_bytes_to_fill -= 5 + 5; |
|
else |
|
PES_bytes_to_fill -= 5; |
|
} |
|
|
|
if (bytes_to_iframe == 0 || s->packet_number == 0) { |
|
size = put_system_header(ctx, buf_ptr, 0); |
|
buf_ptr += size; |
|
size = buf_ptr - buffer; |
|
put_buffer(&ctx->pb, buffer, size); |
|
|
|
put_be32(&ctx->pb, PRIVATE_STREAM_2); |
|
put_be16(&ctx->pb, 0x03d4); // length |
|
put_byte(&ctx->pb, 0x00); // substream ID, 00=PCI |
|
for (i = 0; i < 979; i++) |
|
put_byte(&ctx->pb, 0x00); |
|
|
|
put_be32(&ctx->pb, PRIVATE_STREAM_2); |
|
put_be16(&ctx->pb, 0x03fa); // length |
|
put_byte(&ctx->pb, 0x01); // substream ID, 01=DSI |
|
for (i = 0; i < 1017; i++) |
|
put_byte(&ctx->pb, 0x00); |
|
|
|
memset(buffer, 0, 128); |
|
buf_ptr = buffer; |
|
s->packet_number++; |
|
stream->align_iframe = 0; |
|
scr += s->packet_size*90000LL / (s->mux_rate*50LL); //FIXME rounding and first few bytes of each packet |
|
size = put_pack_header(ctx, buf_ptr, scr); |
|
s->last_scr= scr; |
|
buf_ptr += size; |
|
/* GOP Start */ |
|
} else if (bytes_to_iframe < PES_bytes_to_fill) { |
|
pad_packet_bytes = PES_bytes_to_fill - bytes_to_iframe; |
|
} |
|
} |
|
} else { |
|
if ((s->packet_number % s->system_header_freq) == 0) { |
|
size = put_system_header(ctx, buf_ptr, 0); |
|
buf_ptr += size; |
|
} |
|
} |
|
} |
|
size = buf_ptr - buffer; |
|
put_buffer(&ctx->pb, buffer, size); |
|
|
|
packet_size = s->packet_size - size; |
|
|
|
if (s->is_vcd && id == AUDIO_ID) |
|
/* The VCD standard demands that 20 zero bytes follow |
|
each audio pack (see standard p. IV-8).*/ |
|
zero_trail_bytes += 20; |
|
|
|
if ((s->is_vcd && stream->packet_number==0) |
|
|| (s->is_svcd && s->packet_number==0)) { |
|
/* for VCD the first pack of each stream contains only the pack header, |
|
the system header and lots of padding (see VCD standard p. IV-6). |
|
In the case of an audio pack, 20 zero bytes are also added at |
|
the end.*/ |
|
/* For SVCD we fill the very first pack to increase compatibility with |
|
some DVD players. Not mandated by the standard.*/ |
|
if (s->is_svcd) |
|
general_pack = 1; /* the system header refers to both streams and no stream data*/ |
|
pad_packet_bytes = packet_size - zero_trail_bytes; |
|
} |
|
|
|
packet_size -= pad_packet_bytes + zero_trail_bytes; |
|
|
|
if (packet_size > 0) { |
|
|
|
/* packet header size */ |
|
packet_size -= 6; |
|
|
|
/* packet header */ |
|
if (s->is_mpeg2) { |
|
header_len = 3; |
|
if (stream->packet_number==0) |
|
header_len += 3; /* PES extension */ |
|
header_len += 1; /* obligatory stuffing byte */ |
|
} else { |
|
header_len = 0; |
|
} |
|
if (pts != AV_NOPTS_VALUE) { |
|
if (dts != pts) |
|
header_len += 5 + 5; |
|
else |
|
header_len += 5; |
|
} else { |
|
if (!s->is_mpeg2) |
|
header_len++; |
|
} |
|
|
|
payload_size = packet_size - header_len; |
|
if (id < 0xc0) { |
|
startcode = PRIVATE_STREAM_1; |
|
payload_size -= 1; |
|
if (id >= 0x40) { |
|
payload_size -= 3; |
|
if (id >= 0xa0) |
|
payload_size -= 3; |
|
} |
|
} else { |
|
startcode = 0x100 + id; |
|
} |
|
|
|
stuffing_size = payload_size - fifo_size(&stream->fifo, stream->fifo.rptr); |
|
|
|
// first byte doesnt fit -> reset pts/dts + stuffing |
|
if(payload_size <= trailer_size && pts != AV_NOPTS_VALUE){ |
|
int timestamp_len=0; |
|
if(dts != pts) |
|
timestamp_len += 5; |
|
if(pts != AV_NOPTS_VALUE) |
|
timestamp_len += s->is_mpeg2 ? 5 : 4; |
|
pts=dts= AV_NOPTS_VALUE; |
|
header_len -= timestamp_len; |
|
if (s->is_dvd && stream->align_iframe) { |
|
pad_packet_bytes += timestamp_len; |
|
packet_size -= timestamp_len; |
|
} else { |
|
payload_size += timestamp_len; |
|
} |
|
stuffing_size += timestamp_len; |
|
if(payload_size > trailer_size) |
|
stuffing_size += payload_size - trailer_size; |
|
} |
|
|
|
if (pad_packet_bytes > 0 && pad_packet_bytes <= 7) { // can't use padding, so use stuffing |
|
packet_size += pad_packet_bytes; |
|
payload_size += pad_packet_bytes; // undo the previous adjustment |
|
if (stuffing_size < 0) { |
|
stuffing_size = pad_packet_bytes; |
|
} else { |
|
stuffing_size += pad_packet_bytes; |
|
} |
|
pad_packet_bytes = 0; |
|
} |
|
|
|
if (stuffing_size < 0) |
|
stuffing_size = 0; |
|
if (stuffing_size > 16) { /*<=16 for MPEG-1, <=32 for MPEG-2*/ |
|
pad_packet_bytes += stuffing_size; |
|
packet_size -= stuffing_size; |
|
payload_size -= stuffing_size; |
|
stuffing_size = 0; |
|
} |
|
|
|
nb_frames= get_nb_frames(ctx, stream, payload_size - stuffing_size); |
|
|
|
put_be32(&ctx->pb, startcode); |
|
|
|
put_be16(&ctx->pb, packet_size); |
|
|
|
if (!s->is_mpeg2) |
|
for(i=0;i<stuffing_size;i++) |
|
put_byte(&ctx->pb, 0xff); |
|
|
|
if (s->is_mpeg2) { |
|
put_byte(&ctx->pb, 0x80); /* mpeg2 id */ |
|
|
|
pes_flags=0; |
|
|
|
if (pts != AV_NOPTS_VALUE) { |
|
pes_flags |= 0x80; |
|
if (dts != pts) |
|
pes_flags |= 0x40; |
|
} |
|
|
|
/* Both the MPEG-2 and the SVCD standards demand that the |
|
P-STD_buffer_size field be included in the first packet of |
|
every stream. (see SVCD standard p. 26 V.2.3.1 and V.2.3.2 |
|
and MPEG-2 standard 2.7.7) */ |
|
if (stream->packet_number == 0) |
|
pes_flags |= 0x01; |
|
|
|
put_byte(&ctx->pb, pes_flags); /* flags */ |
|
put_byte(&ctx->pb, header_len - 3 + stuffing_size); |
|
|
|
if (pes_flags & 0x80) /*write pts*/ |
|
put_timestamp(&ctx->pb, (pes_flags & 0x40) ? 0x03 : 0x02, pts); |
|
if (pes_flags & 0x40) /*write dts*/ |
|
put_timestamp(&ctx->pb, 0x01, dts); |
|
|
|
if (pes_flags & 0x01) { /*write pes extension*/ |
|
put_byte(&ctx->pb, 0x10); /* flags */ |
|
|
|
/* P-STD buffer info */ |
|
if (id == AUDIO_ID) |
|
put_be16(&ctx->pb, 0x4000 | stream->max_buffer_size/128); |
|
else |
|
put_be16(&ctx->pb, 0x6000 | stream->max_buffer_size/1024); |
|
} |
|
|
|
} else { |
|
if (pts != AV_NOPTS_VALUE) { |
|
if (dts != pts) { |
|
put_timestamp(&ctx->pb, 0x03, pts); |
|
put_timestamp(&ctx->pb, 0x01, dts); |
|
} else { |
|
put_timestamp(&ctx->pb, 0x02, pts); |
|
} |
|
} else { |
|
put_byte(&ctx->pb, 0x0f); |
|
} |
|
} |
|
|
|
if (s->is_mpeg2) { |
|
/* special stuffing byte that is always written |
|
to prevent accidental generation of start codes. */ |
|
put_byte(&ctx->pb, 0xff); |
|
|
|
for(i=0;i<stuffing_size;i++) |
|
put_byte(&ctx->pb, 0xff); |
|
} |
|
|
|
if (startcode == PRIVATE_STREAM_1) { |
|
put_byte(&ctx->pb, id); |
|
if (id >= 0xa0) { |
|
/* LPCM (XXX: check nb_frames) */ |
|
put_byte(&ctx->pb, 7); |
|
put_be16(&ctx->pb, 4); /* skip 3 header bytes */ |
|
put_byte(&ctx->pb, stream->lpcm_header[0]); |
|
put_byte(&ctx->pb, stream->lpcm_header[1]); |
|
put_byte(&ctx->pb, stream->lpcm_header[2]); |
|
} else if (id >= 0x40) { |
|
/* AC3 */ |
|
put_byte(&ctx->pb, nb_frames); |
|
put_be16(&ctx->pb, trailer_size+1); |
|
} |
|
} |
|
|
|
/* output data */ |
|
if(put_fifo(&ctx->pb, &stream->fifo, payload_size - stuffing_size, &stream->fifo.rptr) < 0) |
|
return -1; |
|
}else{ |
|
payload_size= |
|
stuffing_size= 0; |
|
} |
|
|
|
if (pad_packet_bytes > 0) |
|
put_padding_packet(ctx,&ctx->pb, pad_packet_bytes); |
|
|
|
for(i=0;i<zero_trail_bytes;i++) |
|
put_byte(&ctx->pb, 0x00); |
|
|
|
put_flush_packet(&ctx->pb); |
|
|
|
s->packet_number++; |
|
|
|
/* only increase the stream packet number if this pack actually contains |
|
something that is specific to this stream! I.e. a dedicated header |
|
or some data.*/ |
|
if (!general_pack) |
|
stream->packet_number++; |
|
|
|
return payload_size - stuffing_size; |
|
} |
|
|
|
static void put_vcd_padding_sector(AVFormatContext *ctx) |
|
{ |
|
/* There are two ways to do this padding: writing a sector/pack |
|
of 0 values, or writing an MPEG padding pack. Both seem to |
|
work with most decoders, BUT the VCD standard only allows a 0-sector |
|
(see standard p. IV-4, IV-5). |
|
So a 0-sector it is...*/ |
|
|
|
MpegMuxContext *s = ctx->priv_data; |
|
int i; |
|
|
|
for(i=0;i<s->packet_size;i++) |
|
put_byte(&ctx->pb, 0); |
|
|
|
s->vcd_padding_bytes_written += s->packet_size; |
|
|
|
put_flush_packet(&ctx->pb); |
|
|
|
/* increasing the packet number is correct. The SCR of the following packs |
|
is calculated from the packet_number and it has to include the padding |
|
sector (it represents the sector index, not the MPEG pack index) |
|
(see VCD standard p. IV-6)*/ |
|
s->packet_number++; |
|
} |
|
|
|
#if 0 /* unused, remove? */ |
|
static int64_t get_vcd_scr(AVFormatContext *ctx,int stream_index,int64_t pts) |
|
{ |
|
MpegMuxContext *s = ctx->priv_data; |
|
int64_t scr; |
|
|
|
/* Since the data delivery rate is constant, SCR is computed |
|
using the formula C + i * 1200 where C is the start constant |
|
and i is the pack index. |
|
It is recommended that SCR 0 is at the beginning of the VCD front |
|
margin (a sequence of empty Form 2 sectors on the CD). |
|
It is recommended that the front margin is 30 sectors long, so |
|
we use C = 30*1200 = 36000 |
|
(Note that even if the front margin is not 30 sectors the file |
|
will still be correct according to the standard. It just won't have |
|
the "recommended" value).*/ |
|
scr = 36000 + s->packet_number * 1200; |
|
|
|
return scr; |
|
} |
|
#endif |
|
|
|
static int remove_decoded_packets(AVFormatContext *ctx, int64_t scr){ |
|
// MpegMuxContext *s = ctx->priv_data; |
|
int i; |
|
|
|
for(i=0; i<ctx->nb_streams; i++){ |
|
AVStream *st = ctx->streams[i]; |
|
StreamInfo *stream = st->priv_data; |
|
PacketDesc *pkt_desc= stream->predecode_packet; |
|
|
|
while(pkt_desc && scr > pkt_desc->dts){ //FIXME > vs >= |
|
if(stream->buffer_index < pkt_desc->size || |
|
stream->predecode_packet == stream->premux_packet){ |
|
av_log(ctx, AV_LOG_ERROR, "buffer underflow\n"); |
|
break; |
|
} |
|
stream->buffer_index -= pkt_desc->size; |
|
|
|
stream->predecode_packet= pkt_desc->next; |
|
av_freep(&pkt_desc); |
|
} |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
static int output_packet(AVFormatContext *ctx, int flush){ |
|
MpegMuxContext *s = ctx->priv_data; |
|
AVStream *st; |
|
StreamInfo *stream; |
|
int i, avail_space, es_size, trailer_size; |
|
int best_i= -1; |
|
int best_score= INT_MIN; |
|
int ignore_constraints=0; |
|
int64_t scr= s->last_scr; |
|
PacketDesc *timestamp_packet; |
|
const int64_t max_delay= av_rescale(ctx->max_delay, 90000, AV_TIME_BASE); |
|
|
|
retry: |
|
for(i=0; i<ctx->nb_streams; i++){ |
|
AVStream *st = ctx->streams[i]; |
|
StreamInfo *stream = st->priv_data; |
|
const int avail_data= fifo_size(&stream->fifo, stream->fifo.rptr); |
|
const int space= stream->max_buffer_size - stream->buffer_index; |
|
int rel_space= 1024*space / stream->max_buffer_size; |
|
PacketDesc *next_pkt= stream->premux_packet; |
|
|
|
/* for subtitle, a single PES packet must be generated, |
|
so we flush after every single subtitle packet */ |
|
if(s->packet_size > avail_data && !flush |
|
&& st->codec->codec_type != CODEC_TYPE_SUBTITLE) |
|
return 0; |
|
if(avail_data==0) |
|
continue; |
|
assert(avail_data>0); |
|
|
|
if(space < s->packet_size && !ignore_constraints) |
|
continue; |
|
|
|
if(next_pkt && next_pkt->dts - scr > max_delay) |
|
continue; |
|
|
|
if(rel_space > best_score){ |
|
best_score= rel_space; |
|
best_i = i; |
|
avail_space= space; |
|
} |
|
} |
|
|
|
if(best_i < 0){ |
|
int64_t best_dts= INT64_MAX; |
|
|
|
for(i=0; i<ctx->nb_streams; i++){ |
|
AVStream *st = ctx->streams[i]; |
|
StreamInfo *stream = st->priv_data; |
|
PacketDesc *pkt_desc= stream->predecode_packet; |
|
if(pkt_desc && pkt_desc->dts < best_dts) |
|
best_dts= pkt_desc->dts; |
|
} |
|
|
|
#if 0 |
|
av_log(ctx, AV_LOG_DEBUG, "bumping scr, scr:%f, dts:%f\n", |
|
scr/90000.0, best_dts/90000.0); |
|
#endif |
|
if(best_dts == INT64_MAX) |
|
return 0; |
|
|
|
if(scr >= best_dts+1 && !ignore_constraints){ |
|
av_log(ctx, AV_LOG_ERROR, "packet too large, ignoring buffer limits to mux it\n"); |
|
ignore_constraints= 1; |
|
} |
|
scr= FFMAX(best_dts+1, scr); |
|
if(remove_decoded_packets(ctx, scr) < 0) |
|
return -1; |
|
goto retry; |
|
} |
|
|
|
assert(best_i >= 0); |
|
|
|
st = ctx->streams[best_i]; |
|
stream = st->priv_data; |
|
|
|
assert(fifo_size(&stream->fifo, stream->fifo.rptr) > 0); |
|
|
|
assert(avail_space >= s->packet_size || ignore_constraints); |
|
|
|
timestamp_packet= stream->premux_packet; |
|
if(timestamp_packet->unwritten_size == timestamp_packet->size){ |
|
trailer_size= 0; |
|
}else{ |
|
trailer_size= timestamp_packet->unwritten_size; |
|
timestamp_packet= timestamp_packet->next; |
|
} |
|
|
|
if(timestamp_packet){ |
|
//av_log(ctx, AV_LOG_DEBUG, "dts:%f pts:%f scr:%f stream:%d\n", timestamp_packet->dts/90000.0, timestamp_packet->pts/90000.0, scr/90000.0, best_i); |
|
es_size= flush_packet(ctx, best_i, timestamp_packet->pts, timestamp_packet->dts, scr, trailer_size); |
|
}else{ |
|
assert(fifo_size(&stream->fifo, stream->fifo.rptr) == trailer_size); |
|
es_size= flush_packet(ctx, best_i, AV_NOPTS_VALUE, AV_NOPTS_VALUE, scr, trailer_size); |
|
} |
|
|
|
if (s->is_vcd) { |
|
/* Write one or more padding sectors, if necessary, to reach |
|
the constant overall bitrate.*/ |
|
int vcd_pad_bytes; |
|
|
|
while((vcd_pad_bytes = get_vcd_padding_size(ctx,stream->premux_packet->pts) ) >= s->packet_size){ //FIXME pts cannot be correct here |
|
put_vcd_padding_sector(ctx); |
|
s->last_scr += s->packet_size*90000LL / (s->mux_rate*50LL); //FIXME rounding and first few bytes of each packet |
|
} |
|
} |
|
|
|
stream->buffer_index += es_size; |
|
s->last_scr += s->packet_size*90000LL / (s->mux_rate*50LL); //FIXME rounding and first few bytes of each packet |
|
|
|
while(stream->premux_packet && stream->premux_packet->unwritten_size <= es_size){ |
|
es_size -= stream->premux_packet->unwritten_size; |
|
stream->premux_packet= stream->premux_packet->next; |
|
} |
|
if(es_size) |
|
stream->premux_packet->unwritten_size -= es_size; |
|
|
|
if(remove_decoded_packets(ctx, s->last_scr) < 0) |
|
return -1; |
|
|
|
return 1; |
|
} |
|
|
|
static int mpeg_mux_write_packet(AVFormatContext *ctx, AVPacket *pkt) |
|
{ |
|
MpegMuxContext *s = ctx->priv_data; |
|
int stream_index= pkt->stream_index; |
|
int size= pkt->size; |
|
uint8_t *buf= pkt->data; |
|
AVStream *st = ctx->streams[stream_index]; |
|
StreamInfo *stream = st->priv_data; |
|
int64_t pts, dts; |
|
PacketDesc *pkt_desc; |
|
const int preload= av_rescale(ctx->preload, 90000, AV_TIME_BASE); |
|
const int is_iframe = st->codec->codec_type == CODEC_TYPE_VIDEO && (pkt->flags & PKT_FLAG_KEY); |
|
|
|
pts= pkt->pts; |
|
dts= pkt->dts; |
|
|
|
if(pts != AV_NOPTS_VALUE) pts += preload; |
|
if(dts != AV_NOPTS_VALUE) dts += preload; |
|
|
|
//av_log(ctx, AV_LOG_DEBUG, "dts:%f pts:%f flags:%d stream:%d nopts:%d\n", dts/90000.0, pts/90000.0, pkt->flags, pkt->stream_index, pts != AV_NOPTS_VALUE); |
|
if (!stream->premux_packet) |
|
stream->next_packet = &stream->premux_packet; |
|
*stream->next_packet= |
|
pkt_desc= av_mallocz(sizeof(PacketDesc)); |
|
pkt_desc->pts= pts; |
|
pkt_desc->dts= dts; |
|
pkt_desc->unwritten_size= |
|
pkt_desc->size= size; |
|
if(!stream->predecode_packet) |
|
stream->predecode_packet= pkt_desc; |
|
stream->next_packet= &pkt_desc->next; |
|
|
|
fifo_realloc(&stream->fifo, fifo_size(&stream->fifo, NULL) + size + 1); |
|
|
|
if (s->is_dvd){ |
|
if (is_iframe && (s->packet_number == 0 || (pts - stream->vobu_start_pts >= 36000))) { // min VOBU length 0.4 seconds (mpucoder) |
|
stream->fifo_iframe_ptr = stream->fifo.wptr; |
|
stream->align_iframe = 1; |
|
stream->vobu_start_pts = pts; |
|
} else { |
|
stream->align_iframe = 0; |
|
} |
|
} |
|
|
|
fifo_write(&stream->fifo, buf, size, &stream->fifo.wptr); |
|
|
|
for(;;){ |
|
int ret= output_packet(ctx, 0); |
|
if(ret<=0) |
|
return ret; |
|
} |
|
} |
|
|
|
static int mpeg_mux_end(AVFormatContext *ctx) |
|
{ |
|
// MpegMuxContext *s = ctx->priv_data; |
|
StreamInfo *stream; |
|
int i; |
|
|
|
for(;;){ |
|
int ret= output_packet(ctx, 1); |
|
if(ret<0) |
|
return ret; |
|
else if(ret==0) |
|
break; |
|
} |
|
|
|
/* End header according to MPEG1 systems standard. We do not write |
|
it as it is usually not needed by decoders and because it |
|
complicates MPEG stream concatenation. */ |
|
//put_be32(&ctx->pb, ISO_11172_END_CODE); |
|
//put_flush_packet(&ctx->pb); |
|
|
|
for(i=0;i<ctx->nb_streams;i++) { |
|
stream = ctx->streams[i]->priv_data; |
|
|
|
assert(fifo_size(&stream->fifo, stream->fifo.rptr) == 0); |
|
fifo_free(&stream->fifo); |
|
} |
|
return 0; |
|
} |
|
#endif //CONFIG_MUXERS |
|
|
|
/*********************************************/ |
|
/* demux code */ |
|
|
|
#define MAX_SYNC_SIZE 100000 |
|
|
|
static int mpegps_probe(AVProbeData *p) |
|
{ |
|
uint32_t code= -1; |
|
int sys=0, pspack=0, priv1=0, vid=0, audio=0; |
|
int i; |
|
|
|
for(i=0; i<p->buf_size; i++){ |
|
code = (code<<8) + p->buf[i]; |
|
if ((code & 0xffffff00) == 0x100) { |
|
if(code == SYSTEM_HEADER_START_CODE) sys++; |
|
else if(code == PRIVATE_STREAM_1) priv1++; |
|
else if(code == PACK_START_CODE) pspack++; |
|
else if((code & 0xf0) == VIDEO_ID) vid++; |
|
else if((code & 0xe0) == AUDIO_ID) audio++; |
|
} |
|
} |
|
if(sys && sys*9 <= pspack*10) |
|
return AVPROBE_SCORE_MAX/2+2; // +1 for .mpg |
|
if((priv1 || vid || audio) && (priv1+vid+audio)*9 <= pspack*10) |
|
return AVPROBE_SCORE_MAX/2+2; // +1 for .mpg |
|
if((!!vid ^ !!audio) && !sys && !pspack) /* PES stream */ |
|
return AVPROBE_SCORE_MAX/2+2; |
|
if(vid || audio) /* invalid VDR files */ |
|
return AVPROBE_SCORE_MAX/2+2; |
|
return 0; |
|
} |
|
|
|
|
|
typedef struct MpegDemuxContext { |
|
int header_state; |
|
unsigned char psm_es_type[256]; |
|
} MpegDemuxContext; |
|
|
|
static int mpegps_read_header(AVFormatContext *s, |
|
AVFormatParameters *ap) |
|
{ |
|
MpegDemuxContext *m = s->priv_data; |
|
m->header_state = 0xff; |
|
s->ctx_flags |= AVFMTCTX_NOHEADER; |
|
|
|
/* no need to do more */ |
|
return 0; |
|
} |
|
|
|
static int64_t get_pts(ByteIOContext *pb, int c) |
|
{ |
|
int64_t pts; |
|
int val; |
|
|
|
if (c < 0) |
|
c = get_byte(pb); |
|
pts = (int64_t)((c >> 1) & 0x07) << 30; |
|
val = get_be16(pb); |
|
pts |= (int64_t)(val >> 1) << 15; |
|
val = get_be16(pb); |
|
pts |= (int64_t)(val >> 1); |
|
return pts; |
|
} |
|
|
|
static int find_next_start_code(ByteIOContext *pb, int *size_ptr, |
|
uint32_t *header_state) |
|
{ |
|
unsigned int state, v; |
|
int val, n; |
|
|
|
state = *header_state; |
|
n = *size_ptr; |
|
while (n > 0) { |
|
if (url_feof(pb)) |
|
break; |
|
v = get_byte(pb); |
|
n--; |
|
if (state == 0x000001) { |
|
state = ((state << 8) | v) & 0xffffff; |
|
val = state; |
|
goto found; |
|
} |
|
state = ((state << 8) | v) & 0xffffff; |
|
} |
|
val = -1; |
|
found: |
|
*header_state = state; |
|
*size_ptr = n; |
|
return val; |
|
} |
|
|
|
#if 0 /* unused, remove? */ |
|
/* XXX: optimize */ |
|
static int find_prev_start_code(ByteIOContext *pb, int *size_ptr) |
|
{ |
|
int64_t pos, pos_start; |
|
int max_size, start_code; |
|
|
|
max_size = *size_ptr; |
|
pos_start = url_ftell(pb); |
|
|
|
/* in order to go faster, we fill the buffer */ |
|
pos = pos_start - 16386; |
|
if (pos < 0) |
|
pos = 0; |
|
url_fseek(pb, pos, SEEK_SET); |
|
get_byte(pb); |
|
|
|
pos = pos_start; |
|
for(;;) { |
|
pos--; |
|
if (pos < 0 || (pos_start - pos) >= max_size) { |
|
start_code = -1; |
|
goto the_end; |
|
} |
|
url_fseek(pb, pos, SEEK_SET); |
|
start_code = get_be32(pb); |
|
if ((start_code & 0xffffff00) == 0x100) |
|
break; |
|
} |
|
the_end: |
|
*size_ptr = pos_start - pos; |
|
return start_code; |
|
} |
|
#endif |
|
|
|
/** |
|
* Extracts stream types from a program stream map |
|
* According to ISO/IEC 13818-1 ('MPEG-2 Systems') table 2-35 |
|
* |
|
* @return number of bytes occupied by PSM in the bitstream |
|
*/ |
|
static long mpegps_psm_parse(MpegDemuxContext *m, ByteIOContext *pb) |
|
{ |
|
int psm_length, ps_info_length, es_map_length; |
|
|
|
psm_length = get_be16(pb); |
|
get_byte(pb); |
|
get_byte(pb); |
|
ps_info_length = get_be16(pb); |
|
|
|
/* skip program_stream_info */ |
|
url_fskip(pb, ps_info_length); |
|
es_map_length = get_be16(pb); |
|
|
|
/* at least one es available? */ |
|
while (es_map_length >= 4){ |
|
unsigned char type = get_byte(pb); |
|
unsigned char es_id = get_byte(pb); |
|
uint16_t es_info_length = get_be16(pb); |
|
/* remember mapping from stream id to stream type */ |
|
m->psm_es_type[es_id] = type; |
|
/* skip program_stream_info */ |
|
url_fskip(pb, es_info_length); |
|
es_map_length -= 4 + es_info_length; |
|
} |
|
get_be32(pb); /* crc32 */ |
|
return 2 + psm_length; |
|
} |
|
|
|
/* read the next PES header. Return its position in ppos |
|
(if not NULL), and its start code, pts and dts. |
|
*/ |
|
static int mpegps_read_pes_header(AVFormatContext *s, |
|
int64_t *ppos, int *pstart_code, |
|
int64_t *ppts, int64_t *pdts) |
|
{ |
|
MpegDemuxContext *m = s->priv_data; |
|
int len, size, startcode, c, flags, header_len; |
|
int64_t pts, dts, last_pos; |
|
|
|
last_pos = -1; |
|
redo: |
|
/* next start code (should be immediately after) */ |
|
m->header_state = 0xff; |
|
size = MAX_SYNC_SIZE; |
|
startcode = find_next_start_code(&s->pb, &size, &m->header_state); |
|
//printf("startcode=%x pos=0x%Lx\n", startcode, url_ftell(&s->pb)); |
|
if (startcode < 0) |
|
return AVERROR_IO; |
|
if (startcode == PACK_START_CODE) |
|
goto redo; |
|
if (startcode == SYSTEM_HEADER_START_CODE) |
|
goto redo; |
|
if (startcode == PADDING_STREAM || |
|
startcode == PRIVATE_STREAM_2) { |
|
/* skip them */ |
|
len = get_be16(&s->pb); |
|
url_fskip(&s->pb, len); |
|
goto redo; |
|
} |
|
if (startcode == PROGRAM_STREAM_MAP) { |
|
mpegps_psm_parse(m, &s->pb); |
|
goto redo; |
|
} |
|
|
|
/* find matching stream */ |
|
if (!((startcode >= 0x1c0 && startcode <= 0x1df) || |
|
(startcode >= 0x1e0 && startcode <= 0x1ef) || |
|
(startcode == 0x1bd))) |
|
goto redo; |
|
if (ppos) { |
|
*ppos = url_ftell(&s->pb) - 4; |
|
} |
|
len = get_be16(&s->pb); |
|
pts = AV_NOPTS_VALUE; |
|
dts = AV_NOPTS_VALUE; |
|
/* stuffing */ |
|
for(;;) { |
|
if (len < 1) |
|
goto redo; |
|
c = get_byte(&s->pb); |
|
len--; |
|
/* XXX: for mpeg1, should test only bit 7 */ |
|
if (c != 0xff) |
|
break; |
|
} |
|
if ((c & 0xc0) == 0x40) { |
|
/* buffer scale & size */ |
|
if (len < 2) |
|
goto redo; |
|
get_byte(&s->pb); |
|
c = get_byte(&s->pb); |
|
len -= 2; |
|
} |
|
if ((c & 0xf0) == 0x20) { |
|
if (len < 4) |
|
goto redo; |
|
dts = pts = get_pts(&s->pb, c); |
|
len -= 4; |
|
} else if ((c & 0xf0) == 0x30) { |
|
if (len < 9) |
|
goto redo; |
|
pts = get_pts(&s->pb, c); |
|
dts = get_pts(&s->pb, -1); |
|
len -= 9; |
|
} else if ((c & 0xc0) == 0x80) { |
|
/* mpeg 2 PES */ |
|
#if 0 /* some streams have this field set for no apparent reason */ |
|
if ((c & 0x30) != 0) { |
|
/* Encrypted multiplex not handled */ |
|
goto redo; |
|
} |
|
#endif |
|
flags = get_byte(&s->pb); |
|
header_len = get_byte(&s->pb); |
|
len -= 2; |
|
if (header_len > len) |
|
goto redo; |
|
if ((flags & 0xc0) == 0x80) { |
|
dts = pts = get_pts(&s->pb, -1); |
|
if (header_len < 5) |
|
goto redo; |
|
header_len -= 5; |
|
len -= 5; |
|
} if ((flags & 0xc0) == 0xc0) { |
|
pts = get_pts(&s->pb, -1); |
|
dts = get_pts(&s->pb, -1); |
|
if (header_len < 10) |
|
goto redo; |
|
header_len -= 10; |
|
len -= 10; |
|
} |
|
len -= header_len; |
|
while (header_len > 0) { |
|
get_byte(&s->pb); |
|
header_len--; |
|
} |
|
} |
|
else if( c!= 0xf ) |
|
goto redo; |
|
|
|
if (startcode == PRIVATE_STREAM_1 && !m->psm_es_type[startcode & 0xff]) { |
|
if (len < 1) |
|
goto redo; |
|
startcode = get_byte(&s->pb); |
|
len--; |
|
if (startcode >= 0x80 && startcode <= 0xbf) { |
|
/* audio: skip header */ |
|
if (len < 3) |
|
goto redo; |
|
get_byte(&s->pb); |
|
get_byte(&s->pb); |
|
get_byte(&s->pb); |
|
len -= 3; |
|
} |
|
} |
|
if(dts != AV_NOPTS_VALUE && ppos){ |
|
int i; |
|
for(i=0; i<s->nb_streams; i++){ |
|
if(startcode == s->streams[i]->id) { |
|
av_add_index_entry(s->streams[i], *ppos, dts, 0, 0, AVINDEX_KEYFRAME /* FIXME keyframe? */); |
|
} |
|
} |
|
} |
|
|
|
*pstart_code = startcode; |
|
*ppts = pts; |
|
*pdts = dts; |
|
return len; |
|
} |
|
|
|
static int mpegps_read_packet(AVFormatContext *s, |
|
AVPacket *pkt) |
|
{ |
|
MpegDemuxContext *m = s->priv_data; |
|
AVStream *st; |
|
int len, startcode, i, type, codec_id = 0, es_type; |
|
int64_t pts, dts, dummy_pos; //dummy_pos is needed for the index building to work |
|
|
|
redo: |
|
len = mpegps_read_pes_header(s, &dummy_pos, &startcode, &pts, &dts); |
|
if (len < 0) |
|
return len; |
|
|
|
/* now find stream */ |
|
for(i=0;i<s->nb_streams;i++) { |
|
st = s->streams[i]; |
|
if (st->id == startcode) |
|
goto found; |
|
} |
|
|
|
es_type = m->psm_es_type[startcode & 0xff]; |
|
if(es_type > 0){ |
|
if(es_type == STREAM_TYPE_VIDEO_MPEG1){ |
|
codec_id = CODEC_ID_MPEG2VIDEO; |
|
type = CODEC_TYPE_VIDEO; |
|
} else if(es_type == STREAM_TYPE_VIDEO_MPEG2){ |
|
codec_id = CODEC_ID_MPEG2VIDEO; |
|
type = CODEC_TYPE_VIDEO; |
|
} else if(es_type == STREAM_TYPE_AUDIO_MPEG1 || |
|
es_type == STREAM_TYPE_AUDIO_MPEG2){ |
|
codec_id = CODEC_ID_MP3; |
|
type = CODEC_TYPE_AUDIO; |
|
} else if(es_type == STREAM_TYPE_AUDIO_AAC){ |
|
codec_id = CODEC_ID_AAC; |
|
type = CODEC_TYPE_AUDIO; |
|
} else if(es_type == STREAM_TYPE_VIDEO_MPEG4){ |
|
codec_id = CODEC_ID_MPEG4; |
|
type = CODEC_TYPE_VIDEO; |
|
} else if(es_type == STREAM_TYPE_VIDEO_H264){ |
|
codec_id = CODEC_ID_H264; |
|
type = CODEC_TYPE_VIDEO; |
|
} else if(es_type == STREAM_TYPE_AUDIO_AC3){ |
|
codec_id = CODEC_ID_AC3; |
|
type = CODEC_TYPE_AUDIO; |
|
} else { |
|
goto skip; |
|
} |
|
} else if (startcode >= 0x1e0 && startcode <= 0x1ef) { |
|
static const unsigned char avs_seqh[4] = { 0, 0, 1, 0xb0 }; |
|
unsigned char buf[8]; |
|
get_buffer(&s->pb, buf, 8); |
|
url_fseek(&s->pb, -8, SEEK_CUR); |
|
if(!memcmp(buf, avs_seqh, 4) && (buf[6] != 0 || buf[7] != 1)) |
|
codec_id = CODEC_ID_CAVS; |
|
else |
|
codec_id = CODEC_ID_MPEG2VIDEO; |
|
type = CODEC_TYPE_VIDEO; |
|
} else if (startcode >= 0x1c0 && startcode <= 0x1df) { |
|
type = CODEC_TYPE_AUDIO; |
|
codec_id = CODEC_ID_MP2; |
|
} else if (startcode >= 0x80 && startcode <= 0x87) { |
|
type = CODEC_TYPE_AUDIO; |
|
codec_id = CODEC_ID_AC3; |
|
} else if (startcode >= 0x88 && startcode <= 0x9f) { |
|
type = CODEC_TYPE_AUDIO; |
|
codec_id = CODEC_ID_DTS; |
|
} else if (startcode >= 0xa0 && startcode <= 0xbf) { |
|
type = CODEC_TYPE_AUDIO; |
|
codec_id = CODEC_ID_PCM_S16BE; |
|
} else if (startcode >= 0x20 && startcode <= 0x3f) { |
|
type = CODEC_TYPE_SUBTITLE; |
|
codec_id = CODEC_ID_DVD_SUBTITLE; |
|
} else { |
|
skip: |
|
/* skip packet */ |
|
url_fskip(&s->pb, len); |
|
goto redo; |
|
} |
|
/* no stream found: add a new stream */ |
|
st = av_new_stream(s, startcode); |
|
if (!st) |
|
goto skip; |
|
st->codec->codec_type = type; |
|
st->codec->codec_id = codec_id; |
|
if (codec_id != CODEC_ID_PCM_S16BE) |
|
st->need_parsing = 1; |
|
found: |
|
if(st->discard >= AVDISCARD_ALL) |
|
goto skip; |
|
if (startcode >= 0xa0 && startcode <= 0xbf) { |
|
int b1, freq; |
|
|
|
/* for LPCM, we just skip the header and consider it is raw |
|
audio data */ |
|
if (len <= 3) |
|
goto skip; |
|
get_byte(&s->pb); /* emphasis (1), muse(1), reserved(1), frame number(5) */ |
|
b1 = get_byte(&s->pb); /* quant (2), freq(2), reserved(1), channels(3) */ |
|
get_byte(&s->pb); /* dynamic range control (0x80 = off) */ |
|
len -= 3; |
|
freq = (b1 >> 4) & 3; |
|
st->codec->sample_rate = lpcm_freq_tab[freq]; |
|
st->codec->channels = 1 + (b1 & 7); |
|
st->codec->bit_rate = st->codec->channels * st->codec->sample_rate * 2; |
|
} |
|
av_new_packet(pkt, len); |
|
get_buffer(&s->pb, pkt->data, pkt->size); |
|
pkt->pts = pts; |
|
pkt->dts = dts; |
|
pkt->stream_index = st->index; |
|
#if 0 |
|
av_log(s, AV_LOG_DEBUG, "%d: pts=%0.3f dts=%0.3f size=%d\n", |
|
pkt->stream_index, pkt->pts / 90000.0, pkt->dts / 90000.0, pkt->size); |
|
#endif |
|
|
|
return 0; |
|
} |
|
|
|
static int mpegps_read_close(AVFormatContext *s) |
|
{ |
|
return 0; |
|
} |
|
|
|
static int64_t mpegps_read_dts(AVFormatContext *s, int stream_index, |
|
int64_t *ppos, int64_t pos_limit) |
|
{ |
|
int len, startcode; |
|
int64_t pos, pts, dts; |
|
|
|
pos = *ppos; |
|
#ifdef DEBUG_SEEK |
|
printf("read_dts: pos=0x%llx next=%d -> ", pos, find_next); |
|
#endif |
|
url_fseek(&s->pb, pos, SEEK_SET); |
|
for(;;) { |
|
len = mpegps_read_pes_header(s, &pos, &startcode, &pts, &dts); |
|
if (len < 0) { |
|
#ifdef DEBUG_SEEK |
|
printf("none (ret=%d)\n", len); |
|
#endif |
|
return AV_NOPTS_VALUE; |
|
} |
|
if (startcode == s->streams[stream_index]->id && |
|
dts != AV_NOPTS_VALUE) { |
|
break; |
|
} |
|
url_fskip(&s->pb, len); |
|
} |
|
#ifdef DEBUG_SEEK |
|
printf("pos=0x%llx dts=0x%llx %0.3f\n", pos, dts, dts / 90000.0); |
|
#endif |
|
*ppos = pos; |
|
return dts; |
|
} |
|
|
|
#ifdef CONFIG_MUXERS |
|
static AVOutputFormat mpeg1system_mux = { |
|
"mpeg", |
|
"MPEG1 System format", |
|
"video/mpeg", |
|
"mpg,mpeg", |
|
sizeof(MpegMuxContext), |
|
CODEC_ID_MP2, |
|
CODEC_ID_MPEG1VIDEO, |
|
mpeg_mux_init, |
|
mpeg_mux_write_packet, |
|
mpeg_mux_end, |
|
}; |
|
|
|
static AVOutputFormat mpeg1vcd_mux = { |
|
"vcd", |
|
"MPEG1 System format (VCD)", |
|
"video/mpeg", |
|
NULL, |
|
sizeof(MpegMuxContext), |
|
CODEC_ID_MP2, |
|
CODEC_ID_MPEG1VIDEO, |
|
mpeg_mux_init, |
|
mpeg_mux_write_packet, |
|
mpeg_mux_end, |
|
}; |
|
|
|
static AVOutputFormat mpeg2vob_mux = { |
|
"vob", |
|
"MPEG2 PS format (VOB)", |
|
"video/mpeg", |
|
"vob", |
|
sizeof(MpegMuxContext), |
|
CODEC_ID_MP2, |
|
CODEC_ID_MPEG2VIDEO, |
|
mpeg_mux_init, |
|
mpeg_mux_write_packet, |
|
mpeg_mux_end, |
|
}; |
|
|
|
/* Same as mpeg2vob_mux except that the pack size is 2324 */ |
|
static AVOutputFormat mpeg2svcd_mux = { |
|
"svcd", |
|
"MPEG2 PS format (VOB)", |
|
"video/mpeg", |
|
"vob", |
|
sizeof(MpegMuxContext), |
|
CODEC_ID_MP2, |
|
CODEC_ID_MPEG2VIDEO, |
|
mpeg_mux_init, |
|
mpeg_mux_write_packet, |
|
mpeg_mux_end, |
|
}; |
|
|
|
/* Same as mpeg2vob_mux except the 'is_dvd' flag is set to produce NAV pkts */ |
|
static AVOutputFormat mpeg2dvd_mux = { |
|
"dvd", |
|
"MPEG2 PS format (DVD VOB)", |
|
"video/mpeg", |
|
"dvd", |
|
sizeof(MpegMuxContext), |
|
CODEC_ID_MP2, |
|
CODEC_ID_MPEG2VIDEO, |
|
mpeg_mux_init, |
|
mpeg_mux_write_packet, |
|
mpeg_mux_end, |
|
}; |
|
|
|
#endif //CONFIG_MUXERS |
|
|
|
AVInputFormat mpegps_demux = { |
|
"mpeg", |
|
"MPEG PS format", |
|
sizeof(MpegDemuxContext), |
|
mpegps_probe, |
|
mpegps_read_header, |
|
mpegps_read_packet, |
|
mpegps_read_close, |
|
NULL, //mpegps_read_seek, |
|
mpegps_read_dts, |
|
.flags = AVFMT_SHOW_IDS, |
|
}; |
|
|
|
int mpegps_init(void) |
|
{ |
|
#ifdef CONFIG_MUXERS |
|
av_register_output_format(&mpeg1system_mux); |
|
av_register_output_format(&mpeg1vcd_mux); |
|
av_register_output_format(&mpeg2vob_mux); |
|
av_register_output_format(&mpeg2svcd_mux); |
|
av_register_output_format(&mpeg2dvd_mux); |
|
#endif //CONFIG_MUXERS |
|
av_register_input_format(&mpegps_demux); |
|
return 0; |
|
}
|
|
|