3 * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
24 #include "libavutil/attributes.h"
25 #include "libavutil/fifo.h"
26 #include "libavutil/log.h"
27 #include "libavutil/mathematics.h"
28 #include "libavutil/opt.h"
30 #include "libavcodec/put_bits.h"
36 #define MAX_PAYLOAD_SIZE 4096
38 typedef struct PacketDesc {
43 struct PacketDesc *next;
46 typedef struct StreamInfo {
49 int max_buffer_size; /* in bytes */
51 PacketDesc *predecode_packet;
52 PacketDesc *premux_packet;
53 PacketDesc **next_packet;
55 uint8_t lpcm_header[3];
59 int64_t vobu_start_pts;
62 typedef struct MpegMuxContext {
64 int packet_size; /* required packet size */
66 int pack_header_freq; /* frequency (in packets^-1) at which we send pack headers */
67 int system_header_freq;
68 int system_header_size;
69 int user_mux_rate; /* bitrate in units of bits/s */
70 int mux_rate; /* bitrate in units of 50 bytes/s */
78 int64_t last_scr; /* current system clock */
80 int64_t vcd_padding_bitrate_num;
81 int64_t vcd_padding_bytes_written;
86 extern AVOutputFormat ff_mpeg1vcd_muxer;
87 extern AVOutputFormat ff_mpeg2dvd_muxer;
88 extern AVOutputFormat ff_mpeg2svcd_muxer;
89 extern AVOutputFormat ff_mpeg2vob_muxer;
91 static int put_pack_header(AVFormatContext *ctx, uint8_t *buf,
94 MpegMuxContext *s = ctx->priv_data;
97 init_put_bits(&pb, buf, 128);
99 put_bits32(&pb, PACK_START_CODE);
101 put_bits(&pb, 2, 0x1);
103 put_bits(&pb, 4, 0x2);
104 put_bits(&pb, 3, (uint32_t)((timestamp >> 30) & 0x07));
106 put_bits(&pb, 15, (uint32_t)((timestamp >> 15) & 0x7fff));
108 put_bits(&pb, 15, (uint32_t)((timestamp) & 0x7fff));
111 /* clock extension */
114 put_bits(&pb, 22, s->mux_rate);
118 put_bits(&pb, 5, 0x1f); /* reserved */
119 put_bits(&pb, 3, 0); /* stuffing length */
122 return put_bits_ptr(&pb) - pb.buf;
125 static int put_system_header(AVFormatContext *ctx, uint8_t *buf,
126 int only_for_stream_id)
128 MpegMuxContext *s = ctx->priv_data;
129 int size, i, private_stream_coded, id;
132 init_put_bits(&pb, buf, 128);
134 put_bits32(&pb, SYSTEM_HEADER_START_CODE);
135 put_bits(&pb, 16, 0);
138 /* maximum bit rate of the multiplexed stream */
139 put_bits(&pb, 22, s->mux_rate);
140 put_bits(&pb, 1, 1); /* marker */
141 if (s->is_vcd && only_for_stream_id == VIDEO_ID) {
142 /* This header applies only to the video stream
143 * (see VCD standard p. IV-7) */
146 put_bits(&pb, 6, s->audio_bound);
149 /* see VCD standard, p. IV-7 */
153 put_bits(&pb, 1, 0); /* variable bitrate */
154 put_bits(&pb, 1, 0); /* non constrainted bit stream */
157 if (s->is_vcd || s->is_dvd) {
158 /* see VCD standard p IV-7 */
159 put_bits(&pb, 1, 1); /* audio locked */
160 put_bits(&pb, 1, 1); /* video locked */
162 put_bits(&pb, 1, 0); /* audio locked */
163 put_bits(&pb, 1, 0); /* video locked */
166 put_bits(&pb, 1, 1); /* marker */
168 if (s->is_vcd && (only_for_stream_id & 0xe0) == AUDIO_ID) {
169 /* This header applies only to the audio stream
170 * (see VCD standard p. IV-7) */
173 put_bits(&pb, 5, s->video_bound);
176 put_bits(&pb, 1, 0); /* packet_rate_restriction_flag */
177 put_bits(&pb, 7, 0x7f); /* reserved byte */
179 put_bits(&pb, 8, 0xff); /* reserved byte */
181 /* DVD-Video Stream_bound entries
182 * id (0xB9) video, maximum P-STD for stream 0xE0. (P-STD_buffer_bound_scale = 1)
183 * 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)
184 * id (0xBD) private stream 1 (audio other than MPEG and subpictures). (P-STD_buffer_bound_scale = 1)
185 * id (0xBF) private stream 2, NAV packs, set to 2x1024. */
188 int P_STD_max_video = 0;
189 int P_STD_max_mpeg_audio = 0;
190 int P_STD_max_mpeg_PS1 = 0;
192 for (i = 0; i < ctx->nb_streams; i++) {
193 StreamInfo *stream = ctx->streams[i]->priv_data;
196 if (id == 0xbd && stream->max_buffer_size > P_STD_max_mpeg_PS1) {
197 P_STD_max_mpeg_PS1 = stream->max_buffer_size;
198 } else if (id >= 0xc0 && id <= 0xc7 &&
199 stream->max_buffer_size > P_STD_max_mpeg_audio) {
200 P_STD_max_mpeg_audio = stream->max_buffer_size;
201 } else if (id == 0xe0 &&
202 stream->max_buffer_size > P_STD_max_video) {
203 P_STD_max_video = stream->max_buffer_size;
208 put_bits(&pb, 8, 0xb9); /* stream ID */
211 put_bits(&pb, 13, P_STD_max_video / 1024);
214 if (P_STD_max_mpeg_audio == 0)
215 P_STD_max_mpeg_audio = 4096;
216 put_bits(&pb, 8, 0xb8); /* stream ID */
219 put_bits(&pb, 13, P_STD_max_mpeg_audio / 128);
221 /* private stream 1 */
222 put_bits(&pb, 8, 0xbd); /* stream ID */
225 put_bits(&pb, 13, P_STD_max_mpeg_PS1 / 128);
227 /* private stream 2 */
228 put_bits(&pb, 8, 0xbf); /* stream ID */
231 put_bits(&pb, 13, 2);
233 /* audio stream info */
234 private_stream_coded = 0;
235 for (i = 0; i < ctx->nb_streams; i++) {
236 StreamInfo *stream = ctx->streams[i]->priv_data;
238 /* For VCDs, only include the stream info for the stream
239 * that the pack which contains this system belongs to.
240 * (see VCD standard p. IV-7) */
241 if (!s->is_vcd || stream->id == only_for_stream_id ||
242 only_for_stream_id == 0) {
245 /* special case for private streams (AC-3 uses that) */
246 if (private_stream_coded)
248 private_stream_coded = 1;
251 put_bits(&pb, 8, id); /* stream ID */
256 put_bits(&pb, 13, stream->max_buffer_size / 128);
260 put_bits(&pb, 13, stream->max_buffer_size / 1024);
267 size = put_bits_ptr(&pb) - pb.buf;
268 /* patch packet size */
269 AV_WB16(buf + 4, size - 6);
274 static int get_system_header_size(AVFormatContext *ctx)
276 int buf_index, i, private_stream_coded;
278 MpegMuxContext *s = ctx->priv_data;
281 return 18; // DVD-Video system headers are 18 bytes fixed length.
284 private_stream_coded = 0;
285 for (i = 0; i < ctx->nb_streams; i++) {
286 stream = ctx->streams[i]->priv_data;
287 if (stream->id < 0xc0) {
288 if (private_stream_coded)
290 private_stream_coded = 1;
297 static av_cold int mpeg_mux_init(AVFormatContext *ctx)
299 MpegMuxContext *s = ctx->priv_data;
300 int bitrate, i, mpa_id, mpv_id, h264_id, mps_id, ac3_id, dts_id, lpcm_id, j;
306 s->packet_number = 0;
307 s->is_vcd = (CONFIG_MPEG1VCD_MUXER && ctx->oformat == &ff_mpeg1vcd_muxer);
308 s->is_svcd = (CONFIG_MPEG2SVCD_MUXER && ctx->oformat == &ff_mpeg2svcd_muxer);
309 s->is_mpeg2 = ((CONFIG_MPEG2VOB_MUXER && ctx->oformat == &ff_mpeg2vob_muxer) ||
310 (CONFIG_MPEG2DVD_MUXER && ctx->oformat == &ff_mpeg2dvd_muxer) ||
311 (CONFIG_MPEG2SVCD_MUXER && ctx->oformat == &ff_mpeg2svcd_muxer));
312 s->is_dvd = (CONFIG_MPEG2DVD_MUXER && ctx->oformat == &ff_mpeg2dvd_muxer);
314 if (ctx->packet_size) {
315 if (ctx->packet_size < 20 || ctx->packet_size > (1 << 23) + 10) {
316 av_log(ctx, AV_LOG_ERROR, "Invalid packet size %d\n",
320 s->packet_size = ctx->packet_size;
322 s->packet_size = 2048;
323 if (ctx->max_delay < 0) /* Not set by the caller */
324 ctx->max_delay = AV_TIME_BASE*7/10;
326 s->vcd_padding_bytes_written = 0;
327 s->vcd_padding_bitrate_num = 0;
340 for (i = 0; i < ctx->nb_streams; i++) {
341 st = ctx->streams[i];
342 stream = av_mallocz(sizeof(StreamInfo));
345 st->priv_data = stream;
347 avpriv_set_pts_info(st, 64, 1, 90000);
349 switch (st->codec->codec_type) {
350 case AVMEDIA_TYPE_AUDIO:
352 (st->codec->codec_id == AV_CODEC_ID_AC3 ||
353 st->codec->codec_id == AV_CODEC_ID_DTS ||
354 st->codec->codec_id == AV_CODEC_ID_PCM_S16BE))
355 av_log(ctx, AV_LOG_WARNING,
356 "%s in MPEG-1 system streams is not widely supported, "
357 "consider using the vob or the dvd muxer "
358 "to force a MPEG-2 program stream.\n",
359 avcodec_get_name(st->codec->codec_id));
360 if (st->codec->codec_id == AV_CODEC_ID_AC3) {
361 stream->id = ac3_id++;
362 } else if (st->codec->codec_id == AV_CODEC_ID_DTS) {
363 stream->id = dts_id++;
364 } else if (st->codec->codec_id == AV_CODEC_ID_PCM_S16BE) {
365 stream->id = lpcm_id++;
366 for (j = 0; j < 4; j++) {
367 if (lpcm_freq_tab[j] == st->codec->sample_rate)
372 if (st->codec->channels > 8)
374 stream->lpcm_header[0] = 0x0c;
375 stream->lpcm_header[1] = (st->codec->channels - 1) | (j << 4);
376 stream->lpcm_header[2] = 0x80;
377 stream->lpcm_align = st->codec->channels * 2;
379 stream->id = mpa_id++;
382 /* This value HAS to be used for VCD (see VCD standard, p. IV-7).
383 * Right now it is also used for everything else. */
384 stream->max_buffer_size = 4 * 1024;
387 case AVMEDIA_TYPE_VIDEO:
388 if (st->codec->codec_id == AV_CODEC_ID_H264)
389 stream->id = h264_id++;
391 stream->id = mpv_id++;
392 if (st->codec->rc_buffer_size)
393 stream->max_buffer_size = 6 * 1024 + st->codec->rc_buffer_size / 8;
395 av_log(ctx, AV_LOG_WARNING,
396 "VBV buffer size not set, using default size of 130KB\n"
397 "If you want the mpeg file to be compliant to some specification\n"
398 "Like DVD, VCD or others, make sure you set the correct buffer size\n");
399 // FIXME: this is probably too small as default
400 stream->max_buffer_size = 230 * 1024;
402 if (stream->max_buffer_size > 1024 * 8191) {
403 av_log(ctx, AV_LOG_WARNING, "buffer size %d, too large\n", stream->max_buffer_size);
404 stream->max_buffer_size = 1024 * 8191;
408 case AVMEDIA_TYPE_SUBTITLE:
409 stream->id = mps_id++;
410 stream->max_buffer_size = 16 * 1024;
413 av_log(ctx, AV_LOG_ERROR, "Invalid media type %s for output stream #%d\n",
414 av_get_media_type_string(st->codec->codec_type), i);
415 return AVERROR(EINVAL);
417 stream->fifo = av_fifo_alloc(16);
424 for (i = 0; i < ctx->nb_streams; i++) {
426 st = ctx->streams[i];
427 stream = (StreamInfo *)st->priv_data;
429 if (st->codec->rc_max_rate ||
430 st->codec->codec_type == AVMEDIA_TYPE_VIDEO)
431 codec_rate = st->codec->rc_max_rate;
433 codec_rate = st->codec->bit_rate;
436 codec_rate = (1 << 21) * 8 * 50 / ctx->nb_streams;
438 bitrate += codec_rate;
440 if ((stream->id & 0xe0) == AUDIO_ID)
441 audio_bitrate += codec_rate;
442 else if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO)
443 video_bitrate += codec_rate;
446 if (s->user_mux_rate) {
447 s->mux_rate = (s->user_mux_rate + (8 * 50) - 1) / (8 * 50);
449 /* we increase slightly the bitrate to take into account the
450 * headers. XXX: compute it exactly */
451 bitrate += bitrate / 20;
453 s->mux_rate = (bitrate + (8 * 50) - 1) / (8 * 50);
454 if (s->mux_rate >= (1<<22)) {
455 av_log(ctx, AV_LOG_WARNING, "mux rate %d is too large\n", s->mux_rate);
456 s->mux_rate = (1<<22) - 1;
461 int64_t overhead_rate;
463 /* The VCD standard mandates that the mux_rate field is 3528
464 * (see standard p. IV-6).
465 * The value is actually "wrong", i.e. if you calculate
466 * it using the normal formula and the 75 sectors per second transfer
467 * rate you get a different value because the real pack size is 2324,
468 * not 2352. But the standard explicitly specifies that the mux_rate
469 * field in the header must have this value. */
470 // s->mux_rate = 2352 * 75 / 50; /* = 3528 */
472 /* The VCD standard states that the muxed stream must be
473 * exactly 75 packs / second (the data rate of a single speed cdrom).
474 * Since the video bitrate (probably 1150000 bits/sec) will be below
475 * the theoretical maximum we have to add some padding packets
476 * to make up for the lower data rate.
477 * (cf. VCD standard p. IV-6 ) */
479 /* Add the header overhead to the data rate.
480 * 2279 data bytes per audio pack, 2294 data bytes per video pack */
481 overhead_rate = audio_bitrate * 2294LL * (2324 - 2279);
482 overhead_rate += video_bitrate * 2279LL * (2324 - 2294);
484 /* Add padding so that the full bitrate is 2324*75 bytes/sec */
485 s->vcd_padding_bitrate_num = (2324LL * 75 * 8 - bitrate) * 2279 * 2294 - overhead_rate;
486 #define VCD_PADDING_BITRATE_DEN (2279 * 2294)
489 if (s->is_vcd || s->is_mpeg2)
491 s->pack_header_freq = 1;
493 /* every 2 seconds */
494 s->pack_header_freq = 2 * bitrate / s->packet_size / 8;
496 /* the above seems to make pack_header_freq zero sometimes */
497 if (s->pack_header_freq == 0)
498 s->pack_header_freq = 1;
501 /* every 200 packets. Need to look at the spec. */
502 s->system_header_freq = s->pack_header_freq * 40;
504 /* the standard mandates that there are only two system headers
505 * in the whole file: one in the first packet of each stream.
506 * (see standard p. IV-7 and IV-8) */
507 s->system_header_freq = 0x7fffffff;
509 s->system_header_freq = s->pack_header_freq * 5;
511 for (i = 0; i < ctx->nb_streams; i++) {
512 stream = ctx->streams[i]->priv_data;
513 stream->packet_number = 0;
515 s->system_header_size = get_system_header_size(ctx);
516 s->last_scr = AV_NOPTS_VALUE;
520 for (i = 0; i < ctx->nb_streams; i++)
521 av_freep(&ctx->streams[i]->priv_data);
522 return AVERROR(ENOMEM);
525 static inline void put_timestamp(AVIOContext *pb, int id, int64_t timestamp)
527 avio_w8(pb, (id << 4) | (((timestamp >> 30) & 0x07) << 1) | 1);
528 avio_wb16(pb, (uint16_t)((((timestamp >> 15) & 0x7fff) << 1) | 1));
529 avio_wb16(pb, (uint16_t)((((timestamp) & 0x7fff) << 1) | 1));
532 /* return the number of padding bytes that should be inserted into
533 * the multiplexed stream. */
534 static int get_vcd_padding_size(AVFormatContext *ctx, int64_t pts)
536 MpegMuxContext *s = ctx->priv_data;
539 if (s->vcd_padding_bitrate_num > 0 && pts != AV_NOPTS_VALUE) {
540 int64_t full_pad_bytes;
542 // FIXME: this is wrong
544 av_rescale(s->vcd_padding_bitrate_num, pts, 90000LL * 8 * VCD_PADDING_BITRATE_DEN);
545 pad_bytes = (int)(full_pad_bytes - s->vcd_padding_bytes_written);
548 /* might happen if we have already padded to a later timestamp. This
549 * can occur if another stream has already advanced further. */
556 /* Write an MPEG padding packet header. */
557 static void put_padding_packet(AVFormatContext *ctx, AVIOContext *pb,
560 MpegMuxContext *s = ctx->priv_data;
563 avio_wb32(pb, PADDING_STREAM);
564 avio_wb16(pb, packet_bytes - 6);
571 for (i = 0; i < packet_bytes; i++)
575 static int get_nb_frames(AVFormatContext *ctx, StreamInfo *stream, int len)
578 PacketDesc *pkt_desc = stream->premux_packet;
581 if (pkt_desc->size == pkt_desc->unwritten_size)
583 len -= pkt_desc->unwritten_size;
584 pkt_desc = pkt_desc->next;
590 /* flush the packet on stream stream_index */
591 static int flush_packet(AVFormatContext *ctx, int stream_index,
592 int64_t pts, int64_t dts, int64_t scr, int trailer_size)
594 MpegMuxContext *s = ctx->priv_data;
595 StreamInfo *stream = ctx->streams[stream_index]->priv_data;
597 int size, payload_size, startcode, id, stuffing_size, i, header_len;
600 int zero_trail_bytes = 0;
601 int pad_packet_bytes = 0;
603 /* "general" pack without data specific to one stream? */
604 int general_pack = 0;
609 av_log(ctx, AV_LOG_TRACE, "packet ID=%2x PTS=%0.3f\n", id, pts / 90000.0);
613 if ((s->packet_number % s->pack_header_freq) == 0 || s->last_scr != scr) {
614 /* output pack and systems header if needed */
615 size = put_pack_header(ctx, buf_ptr, scr);
620 /* there is exactly one system header for each stream in a VCD MPEG,
621 * One in the very first video packet and one in the very first
622 * audio packet (see VCD standard p. IV-7 and IV-8). */
624 if (stream->packet_number == 0) {
625 size = put_system_header(ctx, buf_ptr, id);
628 } else if (s->is_dvd) {
629 if (stream->align_iframe || s->packet_number == 0) {
630 int PES_bytes_to_fill = s->packet_size - size - 10;
632 if (pts != AV_NOPTS_VALUE) {
634 PES_bytes_to_fill -= 5 + 5;
636 PES_bytes_to_fill -= 5;
639 if (stream->bytes_to_iframe == 0 || s->packet_number == 0) {
640 size = put_system_header(ctx, buf_ptr, 0);
642 size = buf_ptr - buffer;
643 avio_write(ctx->pb, buffer, size);
645 avio_wb32(ctx->pb, PRIVATE_STREAM_2);
646 avio_wb16(ctx->pb, 0x03d4); // length
647 avio_w8(ctx->pb, 0x00); // substream ID, 00=PCI
648 for (i = 0; i < 979; i++)
649 avio_w8(ctx->pb, 0x00);
651 avio_wb32(ctx->pb, PRIVATE_STREAM_2);
652 avio_wb16(ctx->pb, 0x03fa); // length
653 avio_w8(ctx->pb, 0x01); // substream ID, 01=DSI
654 for (i = 0; i < 1017; i++)
655 avio_w8(ctx->pb, 0x00);
657 memset(buffer, 0, 128);
660 stream->align_iframe = 0;
661 // FIXME: rounding and first few bytes of each packet
662 scr += s->packet_size * 90000LL /
663 (s->mux_rate * 50LL);
664 size = put_pack_header(ctx, buf_ptr, scr);
668 } else if (stream->bytes_to_iframe < PES_bytes_to_fill) {
669 pad_packet_bytes = PES_bytes_to_fill -
670 stream->bytes_to_iframe;
674 if ((s->packet_number % s->system_header_freq) == 0) {
675 size = put_system_header(ctx, buf_ptr, 0);
680 size = buf_ptr - buffer;
681 avio_write(ctx->pb, buffer, size);
683 packet_size = s->packet_size - size;
685 if (s->is_vcd && (id & 0xe0) == AUDIO_ID)
686 /* The VCD standard demands that 20 zero bytes follow
687 * each audio pack (see standard p. IV-8). */
688 zero_trail_bytes += 20;
690 if ((s->is_vcd && stream->packet_number == 0) ||
691 (s->is_svcd && s->packet_number == 0)) {
692 /* for VCD the first pack of each stream contains only the pack header,
693 * the system header and lots of padding (see VCD standard p. IV-6).
694 * In the case of an audio pack, 20 zero bytes are also added at
696 /* For SVCD we fill the very first pack to increase compatibility with
697 * some DVD players. Not mandated by the standard. */
699 /* the system header refers to both streams and no stream data */
701 pad_packet_bytes = packet_size - zero_trail_bytes;
704 packet_size -= pad_packet_bytes + zero_trail_bytes;
706 if (packet_size > 0) {
707 /* packet header size */
713 if (stream->packet_number == 0)
714 header_len += 3; /* PES extension */
715 header_len += 1; /* obligatory stuffing byte */
719 if (pts != AV_NOPTS_VALUE) {
729 payload_size = packet_size - header_len;
731 startcode = PRIVATE_STREAM_1;
739 startcode = 0x100 + id;
742 stuffing_size = payload_size - av_fifo_size(stream->fifo);
744 // first byte does not fit -> reset pts/dts + stuffing
745 if (payload_size <= trailer_size && pts != AV_NOPTS_VALUE) {
746 int timestamp_len = 0;
749 if (pts != AV_NOPTS_VALUE)
750 timestamp_len += s->is_mpeg2 ? 5 : 4;
752 dts = AV_NOPTS_VALUE;
753 header_len -= timestamp_len;
754 if (s->is_dvd && stream->align_iframe) {
755 pad_packet_bytes += timestamp_len;
756 packet_size -= timestamp_len;
758 payload_size += timestamp_len;
760 stuffing_size += timestamp_len;
761 if (payload_size > trailer_size)
762 stuffing_size += payload_size - trailer_size;
765 // can't use padding, so use stuffing
766 if (pad_packet_bytes > 0 && pad_packet_bytes <= 7) {
767 packet_size += pad_packet_bytes;
768 payload_size += pad_packet_bytes; // undo the previous adjustment
769 if (stuffing_size < 0)
770 stuffing_size = pad_packet_bytes;
772 stuffing_size += pad_packet_bytes;
773 pad_packet_bytes = 0;
776 if (stuffing_size < 0)
779 if (startcode == PRIVATE_STREAM_1 && id >= 0xa0) {
780 if (payload_size < av_fifo_size(stream->fifo))
781 stuffing_size += payload_size % stream->lpcm_align;
784 if (stuffing_size > 16) { /* <=16 for MPEG-1, <=32 for MPEG-2 */
785 pad_packet_bytes += stuffing_size;
786 packet_size -= stuffing_size;
787 payload_size -= stuffing_size;
791 nb_frames = get_nb_frames(ctx, stream, payload_size - stuffing_size);
793 avio_wb32(ctx->pb, startcode);
795 avio_wb16(ctx->pb, packet_size);
798 for (i = 0; i < stuffing_size; i++)
799 avio_w8(ctx->pb, 0xff);
802 avio_w8(ctx->pb, 0x80); /* mpeg2 id */
806 if (pts != AV_NOPTS_VALUE) {
812 /* Both the MPEG-2 and the SVCD standards demand that the
813 * P-STD_buffer_size field be included in the first packet of
814 * every stream. (see SVCD standard p. 26 V.2.3.1 and V.2.3.2
815 * and MPEG-2 standard 2.7.7) */
816 if (stream->packet_number == 0)
819 avio_w8(ctx->pb, pes_flags); /* flags */
820 avio_w8(ctx->pb, header_len - 3 + stuffing_size);
822 if (pes_flags & 0x80) /* write pts */
823 put_timestamp(ctx->pb, (pes_flags & 0x40) ? 0x03 : 0x02, pts);
824 if (pes_flags & 0x40) /* write dts */
825 put_timestamp(ctx->pb, 0x01, dts);
827 if (pes_flags & 0x01) { /* write pes extension */
828 avio_w8(ctx->pb, 0x10); /* flags */
830 /* P-STD buffer info */
831 if ((id & 0xe0) == AUDIO_ID)
832 avio_wb16(ctx->pb, 0x4000 | stream->max_buffer_size / 128);
834 avio_wb16(ctx->pb, 0x6000 | stream->max_buffer_size / 1024);
837 if (pts != AV_NOPTS_VALUE) {
839 put_timestamp(ctx->pb, 0x03, pts);
840 put_timestamp(ctx->pb, 0x01, dts);
842 put_timestamp(ctx->pb, 0x02, pts);
845 avio_w8(ctx->pb, 0x0f);
850 /* special stuffing byte that is always written
851 * to prevent accidental generation of start codes. */
852 avio_w8(ctx->pb, 0xff);
854 for (i = 0; i < stuffing_size; i++)
855 avio_w8(ctx->pb, 0xff);
858 if (startcode == PRIVATE_STREAM_1) {
859 avio_w8(ctx->pb, id);
861 /* LPCM (XXX: check nb_frames) */
863 avio_wb16(ctx->pb, 4); /* skip 3 header bytes */
864 avio_w8(ctx->pb, stream->lpcm_header[0]);
865 avio_w8(ctx->pb, stream->lpcm_header[1]);
866 avio_w8(ctx->pb, stream->lpcm_header[2]);
867 } else if (id >= 0x40) {
869 avio_w8(ctx->pb, nb_frames);
870 avio_wb16(ctx->pb, trailer_size + 1);
875 av_assert0(payload_size - stuffing_size <= av_fifo_size(stream->fifo));
876 av_fifo_generic_read(stream->fifo, ctx->pb,
877 payload_size - stuffing_size,
878 (void (*)(void*, void*, int))avio_write);
879 stream->bytes_to_iframe -= payload_size - stuffing_size;
885 if (pad_packet_bytes > 0)
886 put_padding_packet(ctx, ctx->pb, pad_packet_bytes);
888 for (i = 0; i < zero_trail_bytes; i++)
889 avio_w8(ctx->pb, 0x00);
895 /* only increase the stream packet number if this pack actually contains
896 * something that is specific to this stream! I.e. a dedicated header
899 stream->packet_number++;
901 return payload_size - stuffing_size;
904 static void put_vcd_padding_sector(AVFormatContext *ctx)
906 /* There are two ways to do this padding: writing a sector/pack
907 * of 0 values, or writing an MPEG padding pack. Both seem to
908 * work with most decoders, BUT the VCD standard only allows a 0-sector
909 * (see standard p. IV-4, IV-5).
910 * So a 0-sector it is... */
912 MpegMuxContext *s = ctx->priv_data;
915 for (i = 0; i < s->packet_size; i++)
918 s->vcd_padding_bytes_written += s->packet_size;
922 /* increasing the packet number is correct. The SCR of the following packs
923 * is calculated from the packet_number and it has to include the padding
924 * sector (it represents the sector index, not the MPEG pack index)
925 * (see VCD standard p. IV-6) */
929 static int remove_decoded_packets(AVFormatContext *ctx, int64_t scr)
933 for (i = 0; i < ctx->nb_streams; i++) {
934 AVStream *st = ctx->streams[i];
935 StreamInfo *stream = st->priv_data;
936 PacketDesc *pkt_desc;
938 while ((pkt_desc = stream->predecode_packet) &&
939 scr > pkt_desc->dts) { // FIXME: > vs >=
940 if (stream->buffer_index < pkt_desc->size ||
941 stream->predecode_packet == stream->premux_packet) {
942 av_log(ctx, AV_LOG_ERROR,
943 "buffer underflow st=%d bufi=%d size=%d\n",
944 i, stream->buffer_index, pkt_desc->size);
947 stream->buffer_index -= pkt_desc->size;
948 stream->predecode_packet = pkt_desc->next;
956 static int output_packet(AVFormatContext *ctx, int flush)
958 MpegMuxContext *s = ctx->priv_data;
961 int i, avail_space = 0, es_size, trailer_size;
963 int best_score = INT_MIN;
964 int ignore_constraints = 0;
965 int ignore_delay = 0;
966 int64_t scr = s->last_scr;
967 PacketDesc *timestamp_packet;
968 const int64_t max_delay = av_rescale(ctx->max_delay, 90000, AV_TIME_BASE);
971 for (i = 0; i < ctx->nb_streams; i++) {
972 AVStream *st = ctx->streams[i];
973 StreamInfo *stream = st->priv_data;
974 const int avail_data = av_fifo_size(stream->fifo);
975 const int space = stream->max_buffer_size - stream->buffer_index;
976 int rel_space = 1024LL * space / stream->max_buffer_size;
977 PacketDesc *next_pkt = stream->premux_packet;
979 /* for subtitle, a single PES packet must be generated,
980 * so we flush after every single subtitle packet */
981 if (s->packet_size > avail_data && !flush
982 && st->codec->codec_type != AVMEDIA_TYPE_SUBTITLE)
986 av_assert0(avail_data > 0);
988 if (space < s->packet_size && !ignore_constraints)
991 if (next_pkt && next_pkt->dts - scr > max_delay && !ignore_delay)
993 if ( stream->predecode_packet
994 && stream->predecode_packet->size > stream->buffer_index)
996 if (rel_space > best_score) {
997 best_score = rel_space;
1004 int64_t best_dts = INT64_MAX;
1007 for (i = 0; i < ctx->nb_streams; i++) {
1008 AVStream *st = ctx->streams[i];
1009 StreamInfo *stream = st->priv_data;
1010 PacketDesc *pkt_desc = stream->predecode_packet;
1011 if (pkt_desc && pkt_desc->dts < best_dts)
1012 best_dts = pkt_desc->dts;
1013 has_premux |= !!stream->premux_packet;
1016 if (best_dts < INT64_MAX) {
1017 av_log(ctx, AV_LOG_TRACE, "bumping scr, scr:%f, dts:%f\n",
1018 scr / 90000.0, best_dts / 90000.0);
1020 if (scr >= best_dts + 1 && !ignore_constraints) {
1021 av_log(ctx, AV_LOG_ERROR,
1022 "packet too large, ignoring buffer limits to mux it\n");
1023 ignore_constraints = 1;
1025 scr = FFMAX(best_dts + 1, scr);
1026 if (remove_decoded_packets(ctx, scr) < 0)
1028 } else if (has_premux && flush) {
1029 av_log(ctx, AV_LOG_ERROR,
1030 "delay too large, ignoring ...\n");
1032 ignore_constraints = 1;
1039 av_assert0(best_i >= 0);
1041 st = ctx->streams[best_i];
1042 stream = st->priv_data;
1044 av_assert0(av_fifo_size(stream->fifo) > 0);
1046 av_assert0(avail_space >= s->packet_size || ignore_constraints);
1048 timestamp_packet = stream->premux_packet;
1049 if (timestamp_packet->unwritten_size == timestamp_packet->size) {
1052 trailer_size = timestamp_packet->unwritten_size;
1053 timestamp_packet = timestamp_packet->next;
1056 if (timestamp_packet) {
1057 av_log(ctx, AV_LOG_TRACE, "dts:%f pts:%f scr:%f stream:%d\n",
1058 timestamp_packet->dts / 90000.0,
1059 timestamp_packet->pts / 90000.0,
1060 scr / 90000.0, best_i);
1061 es_size = flush_packet(ctx, best_i, timestamp_packet->pts,
1062 timestamp_packet->dts, scr, trailer_size);
1064 av_assert0(av_fifo_size(stream->fifo) == trailer_size);
1065 es_size = flush_packet(ctx, best_i, AV_NOPTS_VALUE, AV_NOPTS_VALUE, scr,
1070 /* Write one or more padding sectors, if necessary, to reach
1071 * the constant overall bitrate. */
1074 // FIXME: pts cannot be correct here
1075 while ((vcd_pad_bytes = get_vcd_padding_size(ctx, stream->premux_packet->pts)) >= s->packet_size) {
1076 put_vcd_padding_sector(ctx);
1077 // FIXME: rounding and first few bytes of each packet
1078 s->last_scr += s->packet_size * 90000LL / (s->mux_rate * 50LL);
1082 stream->buffer_index += es_size;
1083 // FIXME: rounding and first few bytes of each packet
1084 s->last_scr += s->packet_size * 90000LL / (s->mux_rate * 50LL);
1086 while (stream->premux_packet &&
1087 stream->premux_packet->unwritten_size <= es_size) {
1088 es_size -= stream->premux_packet->unwritten_size;
1089 stream->premux_packet = stream->premux_packet->next;
1092 av_assert0(stream->premux_packet);
1093 stream->premux_packet->unwritten_size -= es_size;
1096 if (remove_decoded_packets(ctx, s->last_scr) < 0)
1102 static int mpeg_mux_write_packet(AVFormatContext *ctx, AVPacket *pkt)
1104 int stream_index = pkt->stream_index;
1105 int size = pkt->size;
1106 uint8_t *buf = pkt->data;
1107 MpegMuxContext *s = ctx->priv_data;
1108 AVStream *st = ctx->streams[stream_index];
1109 StreamInfo *stream = st->priv_data;
1111 PacketDesc *pkt_desc;
1113 const int is_iframe = st->codec->codec_type == AVMEDIA_TYPE_VIDEO &&
1114 (pkt->flags & AV_PKT_FLAG_KEY);
1116 preload = av_rescale(s->preload, 90000, AV_TIME_BASE);
1121 if (s->last_scr == AV_NOPTS_VALUE) {
1122 if (dts == AV_NOPTS_VALUE || (dts < preload && ctx->avoid_negative_ts) || s->is_dvd) {
1123 if (dts != AV_NOPTS_VALUE)
1124 s->preload += av_rescale(-dts, AV_TIME_BASE, 90000);
1127 s->last_scr = dts - preload;
1130 preload = av_rescale(s->preload, 90000, AV_TIME_BASE);
1131 av_log(ctx, AV_LOG_DEBUG, "First SCR: %"PRId64" First DTS: %"PRId64"\n", s->last_scr, dts + preload);
1134 if (dts != AV_NOPTS_VALUE) dts += preload;
1135 if (pts != AV_NOPTS_VALUE) pts += preload;
1137 av_log(ctx, AV_LOG_TRACE, "dts:%f pts:%f flags:%d stream:%d nopts:%d\n",
1138 dts / 90000.0, pts / 90000.0, pkt->flags,
1139 pkt->stream_index, pts != AV_NOPTS_VALUE);
1140 if (!stream->premux_packet)
1141 stream->next_packet = &stream->premux_packet;
1142 *stream->next_packet =
1143 pkt_desc = av_mallocz(sizeof(PacketDesc));
1144 pkt_desc->pts = pts;
1145 pkt_desc->dts = dts;
1146 pkt_desc->unwritten_size =
1147 pkt_desc->size = size;
1148 if (!stream->predecode_packet)
1149 stream->predecode_packet = pkt_desc;
1150 stream->next_packet = &pkt_desc->next;
1152 if (av_fifo_realloc2(stream->fifo, av_fifo_size(stream->fifo) + size) < 0)
1156 // min VOBU length 0.4 seconds (mpucoder)
1158 (s->packet_number == 0 ||
1159 (pts - stream->vobu_start_pts >= 36000))) {
1160 stream->bytes_to_iframe = av_fifo_size(stream->fifo);
1161 stream->align_iframe = 1;
1162 stream->vobu_start_pts = pts;
1166 av_fifo_generic_write(stream->fifo, buf, size, NULL);
1169 int ret = output_packet(ctx, 0);
1175 static int mpeg_mux_end(AVFormatContext *ctx)
1181 int ret = output_packet(ctx, 1);
1188 /* End header according to MPEG1 systems standard. We do not write
1189 * it as it is usually not needed by decoders and because it
1190 * complicates MPEG stream concatenation. */
1191 // avio_wb32(ctx->pb, ISO_11172_END_CODE);
1192 // avio_flush(ctx->pb);
1194 for (i = 0; i < ctx->nb_streams; i++) {
1195 stream = ctx->streams[i]->priv_data;
1197 av_assert0(av_fifo_size(stream->fifo) == 0);
1198 av_fifo_freep(&stream->fifo);
1203 #define OFFSET(x) offsetof(MpegMuxContext, x)
1204 #define E AV_OPT_FLAG_ENCODING_PARAM
1205 static const AVOption options[] = {
1206 { "muxrate", NULL, OFFSET(user_mux_rate), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, ((1<<22) - 1) * (8 * 50), E },
1207 { "preload", "Initial demux-decode delay in microseconds.", OFFSET(preload), AV_OPT_TYPE_INT, { .i64 = 500000 }, 0, INT_MAX, E },
1211 #define MPEGENC_CLASS(flavor) \
1212 static const AVClass flavor ## _class = { \
1213 .class_name = #flavor " muxer", \
1214 .item_name = av_default_item_name, \
1215 .version = LIBAVUTIL_VERSION_INT, \
1216 .option = options, \
1219 #if CONFIG_MPEG1SYSTEM_MUXER
1221 AVOutputFormat ff_mpeg1system_muxer = {
1223 .long_name = NULL_IF_CONFIG_SMALL("MPEG-1 Systems / MPEG program stream"),
1224 .mime_type = "video/mpeg",
1225 .extensions = "mpg,mpeg",
1226 .priv_data_size = sizeof(MpegMuxContext),
1227 .audio_codec = AV_CODEC_ID_MP2,
1228 .video_codec = AV_CODEC_ID_MPEG1VIDEO,
1229 .write_header = mpeg_mux_init,
1230 .write_packet = mpeg_mux_write_packet,
1231 .write_trailer = mpeg_mux_end,
1232 .priv_class = &mpeg_class,
1236 #if CONFIG_MPEG1VCD_MUXER
1238 AVOutputFormat ff_mpeg1vcd_muxer = {
1240 .long_name = NULL_IF_CONFIG_SMALL("MPEG-1 Systems / MPEG program stream (VCD)"),
1241 .mime_type = "video/mpeg",
1242 .priv_data_size = sizeof(MpegMuxContext),
1243 .audio_codec = AV_CODEC_ID_MP2,
1244 .video_codec = AV_CODEC_ID_MPEG1VIDEO,
1245 .write_header = mpeg_mux_init,
1246 .write_packet = mpeg_mux_write_packet,
1247 .write_trailer = mpeg_mux_end,
1248 .priv_class = &vcd_class,
1252 #if CONFIG_MPEG2VOB_MUXER
1254 AVOutputFormat ff_mpeg2vob_muxer = {
1256 .long_name = NULL_IF_CONFIG_SMALL("MPEG-2 PS (VOB)"),
1257 .mime_type = "video/mpeg",
1258 .extensions = "vob",
1259 .priv_data_size = sizeof(MpegMuxContext),
1260 .audio_codec = AV_CODEC_ID_MP2,
1261 .video_codec = AV_CODEC_ID_MPEG2VIDEO,
1262 .write_header = mpeg_mux_init,
1263 .write_packet = mpeg_mux_write_packet,
1264 .write_trailer = mpeg_mux_end,
1265 .priv_class = &vob_class,
1269 /* Same as mpeg2vob_mux except that the pack size is 2324 */
1270 #if CONFIG_MPEG2SVCD_MUXER
1272 AVOutputFormat ff_mpeg2svcd_muxer = {
1274 .long_name = NULL_IF_CONFIG_SMALL("MPEG-2 PS (SVCD)"),
1275 .mime_type = "video/mpeg",
1276 .extensions = "vob",
1277 .priv_data_size = sizeof(MpegMuxContext),
1278 .audio_codec = AV_CODEC_ID_MP2,
1279 .video_codec = AV_CODEC_ID_MPEG2VIDEO,
1280 .write_header = mpeg_mux_init,
1281 .write_packet = mpeg_mux_write_packet,
1282 .write_trailer = mpeg_mux_end,
1283 .priv_class = &svcd_class,
1287 /* Same as mpeg2vob_mux except the 'is_dvd' flag is set to produce NAV pkts */
1288 #if CONFIG_MPEG2DVD_MUXER
1290 AVOutputFormat ff_mpeg2dvd_muxer = {
1292 .long_name = NULL_IF_CONFIG_SMALL("MPEG-2 PS (DVD VOB)"),
1293 .mime_type = "video/mpeg",
1294 .extensions = "dvd",
1295 .priv_data_size = sizeof(MpegMuxContext),
1296 .audio_codec = AV_CODEC_ID_MP2,
1297 .video_codec = AV_CODEC_ID_MPEG2VIDEO,
1298 .write_header = mpeg_mux_init,
1299 .write_packet = mpeg_mux_write_packet,
1300 .write_trailer = mpeg_mux_end,
1301 .priv_class = &dvd_class,