diff options
Diffstat (limited to 'libavformat/mpegenc.c')
| -rw-r--r-- | libavformat/mpegenc.c | 1297 |
1 files changed, 1297 insertions, 0 deletions
diff --git a/libavformat/mpegenc.c b/libavformat/mpegenc.c new file mode 100644 index 0000000000..464a1f7bd7 --- /dev/null +++ b/libavformat/mpegenc.c @@ -0,0 +1,1297 @@ +/* + * MPEG1/2 muxer + * Copyright (c) 2000, 2001, 2002 Fabrice Bellard. + * + * This file is part of FFmpeg. + * + * FFmpeg is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * FFmpeg is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include "avformat.h" +#include "bitstream.h" +#include "fifo.h" +#include "mpeg.h" + +#define MAX_PAYLOAD_SIZE 4096 +//#define DEBUG_SEEK + +#undef NDEBUG +#include <assert.h> + +typedef struct PacketDesc { + int64_t pts; + int64_t dts; + int size; + int unwritten_size; + int flags; + struct PacketDesc *next; +} PacketDesc; + +typedef struct { + AVFifoBuffer fifo; + uint8_t id; + int max_buffer_size; /* in bytes */ + int buffer_index; + PacketDesc *predecode_packet; + PacketDesc *premux_packet; + PacketDesc **next_packet; + int packet_number; + uint8_t lpcm_header[3]; + int lpcm_align; + int bytes_to_iframe; + int align_iframe; + int64_t vobu_start_pts; +} StreamInfo; + +typedef struct { + int packet_size; /* required packet size */ + int packet_number; + int pack_header_freq; /* frequency (in packets^-1) at which we send pack headers */ + int system_header_freq; + int system_header_size; + int mux_rate; /* bitrate in units of 50 bytes/s */ + /* stream info */ + int audio_bound; + int video_bound; + int is_mpeg2; + int is_vcd; + int is_svcd; + int is_dvd; + int64_t last_scr; /* current system clock */ + + double vcd_padding_bitrate; //FIXME floats + int64_t vcd_padding_bytes_written; + +} MpegMuxContext; + +#ifdef CONFIG_MUXERS +AVOutputFormat mpeg1system_muxer; +AVOutputFormat mpeg1vcd_muxer; +AVOutputFormat mpeg2vob_muxer; +AVOutputFormat mpeg2svcd_muxer; +AVOutputFormat mpeg2dvd_muxer; + +static int put_pack_header(AVFormatContext *ctx, + uint8_t *buf, int64_t timestamp) +{ + MpegMuxContext *s = ctx->priv_data; + PutBitContext pb; + + init_put_bits(&pb, buf, 128); + + put_bits(&pb, 32, PACK_START_CODE); + if (s->is_mpeg2) { + put_bits(&pb, 2, 0x1); + } else { + put_bits(&pb, 4, 0x2); + } + put_bits(&pb, 3, (uint32_t)((timestamp >> 30) & 0x07)); + put_bits(&pb, 1, 1); + put_bits(&pb, 15, (uint32_t)((timestamp >> 15) & 0x7fff)); + put_bits(&pb, 1, 1); + put_bits(&pb, 15, (uint32_t)((timestamp) & 0x7fff)); + put_bits(&pb, 1, 1); + if (s->is_mpeg2) { + /* clock extension */ + put_bits(&pb, 9, 0); + } + put_bits(&pb, 1, 1); + put_bits(&pb, 22, s->mux_rate); + put_bits(&pb, 1, 1); + if (s->is_mpeg2) { + put_bits(&pb, 1, 1); + put_bits(&pb, 5, 0x1f); /* reserved */ + put_bits(&pb, 3, 0); /* stuffing length */ + } + flush_put_bits(&pb); + return pbBufPtr(&pb) - pb.buf; +} + +static int put_system_header(AVFormatContext *ctx, uint8_t *buf,int only_for_stream_id) +{ + MpegMuxContext *s = ctx->priv_data; + int size, i, private_stream_coded, id; + PutBitContext pb; + + init_put_bits(&pb, buf, 128); + + put_bits(&pb, 32, SYSTEM_HEADER_START_CODE); + put_bits(&pb, 16, 0); + put_bits(&pb, 1, 1); + + put_bits(&pb, 22, s->mux_rate); /* maximum bit rate of the multiplexed stream */ + put_bits(&pb, 1, 1); /* marker */ + if (s->is_vcd && only_for_stream_id==VIDEO_ID) { + /* This header applies only to the video stream (see VCD standard p. IV-7)*/ + put_bits(&pb, 6, 0); + } else + put_bits(&pb, 6, s->audio_bound); + + if (s->is_vcd) { + /* see VCD standard, p. IV-7*/ + put_bits(&pb, 1, 0); + put_bits(&pb, 1, 1); + } else { + put_bits(&pb, 1, 0); /* variable bitrate*/ + put_bits(&pb, 1, 0); /* non constrainted bit stream */ + } + + if (s->is_vcd || s->is_dvd) { + /* see VCD standard p IV-7 */ + put_bits(&pb, 1, 1); /* audio locked */ + put_bits(&pb, 1, 1); /* video locked */ + } else { + put_bits(&pb, 1, 0); /* audio locked */ + put_bits(&pb, 1, 0); /* video locked */ + } + + put_bits(&pb, 1, 1); /* marker */ + + if (s->is_vcd && only_for_stream_id==AUDIO_ID) { + /* This header applies only to the audio stream (see VCD standard p. IV-7)*/ + put_bits(&pb, 5, 0); + } else + put_bits(&pb, 5, s->video_bound); + + if (s->is_dvd) { + put_bits(&pb, 1, 0); /* packet_rate_restriction_flag */ + put_bits(&pb, 7, 0x7f); /* reserved byte */ + } else + put_bits(&pb, 8, 0xff); /* reserved byte */ + + /* DVD-Video Stream_bound entries + id (0xB9) video, maximum P-STD for stream 0xE0. (P-STD_buffer_bound_scale = 1) + 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) + id (0xBD) private stream 1 (audio other than MPEG and subpictures). (P-STD_buffer_bound_scale = 1) + id (0xBF) private stream 2, NAV packs, set to 2x1024. */ + if (s->is_dvd) { + + int P_STD_max_video = 0; + int P_STD_max_mpeg_audio = 0; + int P_STD_max_mpeg_PS1 = 0; + + for(i=0;i<ctx->nb_streams;i++) { + StreamInfo *stream = ctx->streams[i]->priv_data; + + id = stream->id; + if (id == 0xbd && stream->max_buffer_size > P_STD_max_mpeg_PS1) { + P_STD_max_mpeg_PS1 = stream->max_buffer_size; + } else if (id >= 0xc0 && id <= 0xc7 && stream->max_buffer_size > P_STD_max_mpeg_audio) { + P_STD_max_mpeg_audio = stream->max_buffer_size; + } else if (id == 0xe0 && stream->max_buffer_size > P_STD_max_video) { + P_STD_max_video = stream->max_buffer_size; + } + } + + /* video */ + put_bits(&pb, 8, 0xb9); /* stream ID */ + put_bits(&pb, 2, 3); + put_bits(&pb, 1, 1); + put_bits(&pb, 13, P_STD_max_video / 1024); + + /* audio */ + if (P_STD_max_mpeg_audio == 0) + P_STD_max_mpeg_audio = 4096; + put_bits(&pb, 8, 0xb8); /* stream ID */ + put_bits(&pb, 2, 3); + put_bits(&pb, 1, 0); + put_bits(&pb, 13, P_STD_max_mpeg_audio / 128); + + /* private stream 1 */ + put_bits(&pb, 8, 0xbd); /* stream ID */ + put_bits(&pb, 2, 3); + put_bits(&pb, 1, 0); + put_bits(&pb, 13, P_STD_max_mpeg_PS1 / 128); + + /* private stream 2 */ + put_bits(&pb, 8, 0xbf); /* stream ID */ + put_bits(&pb, 2, 3); + put_bits(&pb, 1, 1); + put_bits(&pb, 13, 2); + } + else { + /* audio stream info */ + private_stream_coded = 0; + for(i=0;i<ctx->nb_streams;i++) { + StreamInfo *stream = ctx->streams[i]->priv_data; + + + /* For VCDs, only include the stream info for the stream + that the pack which contains this system belongs to. + (see VCD standard p. IV-7) */ + if ( !s->is_vcd || stream->id==only_for_stream_id + || only_for_stream_id==0) { + + id = stream->id; + if (id < 0xc0) { + /* special case for private streams (AC3 use that) */ + if (private_stream_coded) + continue; + private_stream_coded = 1; + id = 0xbd; + } + put_bits(&pb, 8, id); /* stream ID */ + put_bits(&pb, 2, 3); + if (id < 0xe0) { + /* audio */ + put_bits(&pb, 1, 0); + put_bits(&pb, 13, stream->max_buffer_size / 128); + } else { + /* video */ + put_bits(&pb, 1, 1); + put_bits(&pb, 13, stream->max_buffer_size / 1024); + } + } + } + } + + flush_put_bits(&pb); + size = pbBufPtr(&pb) - pb.buf; + /* patch packet size */ + buf[4] = (size - 6) >> 8; + buf[5] = (size - 6) & 0xff; + + return size; +} + +static int get_system_header_size(AVFormatContext *ctx) +{ + int buf_index, i, private_stream_coded; + StreamInfo *stream; + MpegMuxContext *s = ctx->priv_data; + + if (s->is_dvd) + return 18; // DVD-Video system headers are 18 bytes fixed length. + + buf_index = 12; + private_stream_coded = 0; + for(i=0;i<ctx->nb_streams;i++) { + stream = ctx->streams[i]->priv_data; + if (stream->id < 0xc0) { + if (private_stream_coded) + continue; + private_stream_coded = 1; + } + buf_index += 3; + } + return buf_index; +} + +static int mpeg_mux_init(AVFormatContext *ctx) +{ + MpegMuxContext *s = ctx->priv_data; + int bitrate, i, mpa_id, mpv_id, mps_id, ac3_id, dts_id, lpcm_id, j; + AVStream *st; + StreamInfo *stream; + int audio_bitrate; + int video_bitrate; + + s->packet_number = 0; + s->is_vcd = (ctx->oformat == &mpeg1vcd_muxer); + s->is_svcd = (ctx->oformat == &mpeg2svcd_muxer); + s->is_mpeg2 = (ctx->oformat == &mpeg2vob_muxer || ctx->oformat == &mpeg2svcd_muxer || ctx->oformat == &mpeg2dvd_muxer); + s->is_dvd = (ctx->oformat == &mpeg2dvd_muxer); + + if(ctx->packet_size) + s->packet_size = ctx->packet_size; + else + s->packet_size = 2048; + + s->vcd_padding_bytes_written = 0; + s->vcd_padding_bitrate=0; + + s->audio_bound = 0; + s->video_bound = 0; + mpa_id = AUDIO_ID; + ac3_id = AC3_ID; + dts_id = DTS_ID; + mpv_id = VIDEO_ID; + mps_id = SUB_ID; + lpcm_id = LPCM_ID; + for(i=0;i<ctx->nb_streams;i++) { + st = ctx->streams[i]; + stream = av_mallocz(sizeof(StreamInfo)); + if (!stream) + goto fail; + st->priv_data = stream; + + av_set_pts_info(st, 64, 1, 90000); + + switch(st->codec->codec_type) { + case CODEC_TYPE_AUDIO: + if (st->codec->codec_id == CODEC_ID_AC3) { + stream->id = ac3_id++; + } else if (st->codec->codec_id == CODEC_ID_DTS) { + stream->id = dts_id++; + } else if (st->codec->codec_id == CODEC_ID_PCM_S16BE) { + stream->id = lpcm_id++; + for(j = 0; j < 4; j++) { + if (lpcm_freq_tab[j] == st->codec->sample_rate) + break; + } + if (j == 4) + goto fail; + if (st->codec->channels > 8) + return -1; + stream->lpcm_header[0] = 0x0c; + stream->lpcm_header[1] = (st->codec->channels - 1) | (j << 4); + stream->lpcm_header[2] = 0x80; + stream->lpcm_align = st->codec->channels * 2; + } else { + stream->id = mpa_id++; + } + + /* 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; + s->audio_bound++; + break; + case CODEC_TYPE_VIDEO: + stream->id = mpv_id++; + if (st->codec->rc_buffer_size) + stream->max_buffer_size = 6*1024 + st->codec->rc_buffer_size/8; + else + stream->max_buffer_size = 230*1024; //FIXME this is probably too small as default +#if 0 + /* see VCD standard, p. IV-7*/ + stream->max_buffer_size = 46 * 1024; + else + /* 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; + } + av_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 AVERROR(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 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 (stream->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 (stream->bytes_to_iframe < PES_bytes_to_fill) { + pad_packet_bytes = PES_bytes_to_fill - stream->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 - av_fifo_size(&stream->fifo); + + // first byte does not 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(av_fifo_generic_read(&stream->fifo, payload_size - stuffing_size, &put_buffer, &ctx->pb) < 0) + return -1; + stream->bytes_to_iframe -= payload_size - stuffing_size; + }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; + + while((pkt_desc= stream->predecode_packet) + && 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 i=%d bufi=%d size=%d\n", + i, stream->buffer_index, pkt_desc->size); + 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= av_fifo_size(&stream->fifo); + 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(av_fifo_size(&stream->fifo) > 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(av_fifo_size(&stream->fifo) == 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; + + av_fifo_realloc(&stream->fifo, av_fifo_size(&stream->fifo) + 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->bytes_to_iframe = av_fifo_size(&stream->fifo); + stream->align_iframe = 1; + stream->vobu_start_pts = pts; + } else { + stream->align_iframe = 0; + } + } + + av_fifo_write(&stream->fifo, buf, size); + + 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(av_fifo_size(&stream->fifo) == 0); + av_fifo_free(&stream->fifo); + } + return 0; +} +#endif //CONFIG_MUXERS + +#ifdef CONFIG_MPEG1SYSTEM_MUXER +AVOutputFormat mpeg1system_muxer = { + "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, +}; +#endif +#ifdef CONFIG_MPEG1VCD_MUXER +AVOutputFormat mpeg1vcd_muxer = { + "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, +}; +#endif +#ifdef CONFIG_MPEG2VOB_MUXER +AVOutputFormat mpeg2vob_muxer = { + "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, +}; +#endif + +/* Same as mpeg2vob_mux except that the pack size is 2324 */ +#ifdef CONFIG_MPEG2SVCD_MUXER +AVOutputFormat mpeg2svcd_muxer = { + "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, +}; +#endif + +/* Same as mpeg2vob_mux except the 'is_dvd' flag is set to produce NAV pkts */ +#ifdef CONFIG_MPEG2DVD_MUXER +AVOutputFormat mpeg2dvd_muxer = { + "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 |