3 * Copyright (c) 2004-2007 Michael Niedermayer
5 * This file is part of Libav.
7 * Libav 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 * Libav 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 Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 #include "libavutil/intreadwrite.h"
23 #include "libavutil/mathematics.h"
24 #include "libavutil/tree.h"
25 #include "libavutil/dict.h"
26 #include "libavcodec/mpegaudiodata.h"
29 #include "avio_internal.h"
32 static int find_expected_header(AVCodecContext *c, int size, int key_frame,
35 int sample_rate = c->sample_rate;
42 if (c->codec_id == AV_CODEC_ID_MPEG4) {
49 } else if (c->codec_id == AV_CODEC_ID_MPEG1VIDEO ||
50 c->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
52 } else if (c->codec_id == AV_CODEC_ID_H264) {
54 } else if (c->codec_id == AV_CODEC_ID_MP3 ||
55 c->codec_id == AV_CODEC_ID_MP2) {
56 int lsf, mpeg25, sample_rate_index, bitrate_index, frame_size;
57 int layer = c->codec_id == AV_CODEC_ID_MP3 ? 3 : 2;
58 unsigned int header = 0xFFF00000;
60 lsf = sample_rate < (24000 + 32000) / 2;
61 mpeg25 = sample_rate < (12000 + 16000) / 2;
62 sample_rate <<= lsf + mpeg25;
63 if (sample_rate < (32000 + 44100) / 2)
64 sample_rate_index = 2;
65 else if (sample_rate < (44100 + 48000) / 2)
66 sample_rate_index = 0;
68 sample_rate_index = 1;
70 sample_rate = avpriv_mpa_freq_tab[sample_rate_index] >> (lsf + mpeg25);
72 for (bitrate_index = 2; bitrate_index < 30; bitrate_index++) {
74 avpriv_mpa_bitrate_tab[lsf][layer - 1][bitrate_index >> 1];
75 frame_size = (frame_size * 144000) / (sample_rate << lsf) +
78 if (frame_size == size)
82 header |= (!lsf) << 19;
83 header |= (4 - layer) << 17;
84 header |= 1 << 16; //no crc
87 return 2; //we guess there is no crc, if there is one the user clearly does not care about overhead
88 if (bitrate_index == 30)
89 return -1; //something is wrong ...
91 header |= (bitrate_index >> 1) << 12;
92 header |= sample_rate_index << 10;
93 header |= (bitrate_index & 1) << 9;
95 return 2; //FIXME actually put the needed ones in build_elision_headers()
96 //return 3; //we guess that the private bit is not set
97 //FIXME the above assumptions should be checked, if these turn out false too often something should be done
102 static int find_header_idx(AVFormatContext *s, AVCodecContext *c, int size,
105 NUTContext *nut = s->priv_data;
108 int len = find_expected_header(c, size, frame_type, out);
110 for (i = 1; i < nut->header_count; i++) {
111 if (len == nut->header_len[i] && !memcmp(out, nut->header[i], len)) {
119 static void build_elision_headers(AVFormatContext *s)
121 NUTContext *nut = s->priv_data;
124 //FIXME write a 2pass mode to find the maximal headers
125 static const uint8_t headers[][5] = {
126 { 3, 0x00, 0x00, 0x01 },
127 { 4, 0x00, 0x00, 0x01, 0xB6},
128 { 2, 0xFF, 0xFA }, //mp3+crc
129 { 2, 0xFF, 0xFB }, //mp3
130 { 2, 0xFF, 0xFC }, //mp2+crc
131 { 2, 0xFF, 0xFD }, //mp2
134 nut->header_count = 7;
135 for (i = 1; i < nut->header_count; i++) {
136 nut->header_len[i] = headers[i - 1][0];
137 nut->header[i] = &headers[i - 1][1];
141 static void build_frame_code(AVFormatContext *s)
143 NUTContext *nut = s->priv_data;
144 int key_frame, index, pred, stream_id;
147 int keyframe_0_esc = s->nb_streams > 2;
151 ft = &nut->frame_code[start];
152 ft->flags = FLAG_CODED;
157 if (keyframe_0_esc) {
158 /* keyframe = 0 escape */
159 FrameCode *ft = &nut->frame_code[start];
160 ft->flags = FLAG_STREAM_ID | FLAG_SIZE_MSB | FLAG_CODED_PTS;
165 for (stream_id = 0; stream_id < s->nb_streams; stream_id++) {
166 int start2 = start + (end - start) * stream_id / s->nb_streams;
167 int end2 = start + (end - start) * (stream_id + 1) / s->nb_streams;
168 AVCodecContext *codec = s->streams[stream_id]->codec;
169 int is_audio = codec->codec_type == AVMEDIA_TYPE_AUDIO;
170 int intra_only = /*codec->intra_only || */ is_audio;
173 for (key_frame = 0; key_frame < 2; key_frame++) {
174 if (!intra_only || !keyframe_0_esc || key_frame != 0) {
175 FrameCode *ft = &nut->frame_code[start2];
176 ft->flags = FLAG_KEY * key_frame;
177 ft->flags |= FLAG_SIZE_MSB | FLAG_CODED_PTS;
178 ft->stream_id = stream_id;
181 ft->header_idx = find_header_idx(s, codec, -1, key_frame);
186 key_frame = intra_only;
188 int frame_bytes = codec->frame_size * (int64_t)codec->bit_rate /
189 (8 * codec->sample_rate);
191 for (pts = 0; pts < 2; pts++)
192 for (pred = 0; pred < 2; pred++) {
193 FrameCode *ft = &nut->frame_code[start2];
194 ft->flags = FLAG_KEY * key_frame;
195 ft->stream_id = stream_id;
196 ft->size_mul = frame_bytes + 2;
197 ft->size_lsb = frame_bytes + pred;
199 ft->header_idx = find_header_idx(s, codec, frame_bytes + pred, key_frame);
203 FrameCode *ft = &nut->frame_code[start2];
204 ft->flags = FLAG_KEY | FLAG_SIZE_MSB;
205 ft->stream_id = stream_id;
211 if (codec->has_b_frames) {
218 } else if (codec->codec_id == AV_CODEC_ID_VORBIS) {
228 for (pred = 0; pred < pred_count; pred++) {
229 int start3 = start2 + (end2 - start2) * pred / pred_count;
230 int end3 = start2 + (end2 - start2) * (pred + 1) / pred_count;
232 for (index = start3; index < end3; index++) {
233 FrameCode *ft = &nut->frame_code[index];
234 ft->flags = FLAG_KEY * key_frame;
235 ft->flags |= FLAG_SIZE_MSB;
236 ft->stream_id = stream_id;
237 //FIXME use single byte size and pred from last
238 ft->size_mul = end3 - start3;
239 ft->size_lsb = index - start3;
240 ft->pts_delta = pred_table[pred];
242 ft->header_idx = find_header_idx(s, codec, -1, key_frame);
246 memmove(&nut->frame_code['N' + 1], &nut->frame_code['N'],
247 sizeof(FrameCode) * (255 - 'N'));
248 nut->frame_code[0].flags =
249 nut->frame_code[255].flags =
250 nut->frame_code['N'].flags = FLAG_INVALID;
253 static void put_tt(NUTContext *nut, AVRational *time_base, AVIOContext *bc,
256 val *= nut->time_base_count;
257 val += time_base - nut->time_base;
261 * Store a string as vb.
263 static void put_str(AVIOContext *bc, const char *string)
265 int len = strlen(string);
268 avio_write(bc, string, len);
271 static void put_s(AVIOContext *bc, int64_t val)
273 ff_put_v(bc, 2 * FFABS(val) - (val > 0));
277 static inline void ff_put_v_trace(AVIOContext *bc, uint64_t v, const char *file,
278 const char *func, int line)
280 av_log(NULL, AV_LOG_DEBUG, "ff_put_v %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
285 static inline void put_s_trace(AVIOContext *bc, int64_t v, const char *file,
286 const char *func, int line)
288 av_log(NULL, AV_LOG_DEBUG, "put_s %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
292 #define ff_put_v(bc, v) ff_put_v_trace(bc, v, __FILE__, __PRETTY_FUNCTION__, __LINE__)
293 #define put_s(bc, v) put_s_trace(bc, v, __FILE__, __PRETTY_FUNCTION__, __LINE__)
296 //FIXME remove calculate_checksum
297 static void put_packet(NUTContext *nut, AVIOContext *bc, AVIOContext *dyn_bc,
298 int calculate_checksum, uint64_t startcode)
300 uint8_t *dyn_buf = NULL;
301 int dyn_size = avio_close_dyn_buf(dyn_bc, &dyn_buf);
302 int forw_ptr = dyn_size + 4 * calculate_checksum;
305 ffio_init_checksum(bc, ff_crc04C11DB7_update, 0);
306 avio_wb64(bc, startcode);
307 ff_put_v(bc, forw_ptr);
309 avio_wl32(bc, ffio_get_checksum(bc));
311 if (calculate_checksum)
312 ffio_init_checksum(bc, ff_crc04C11DB7_update, 0);
313 avio_write(bc, dyn_buf, dyn_size);
314 if (calculate_checksum)
315 avio_wl32(bc, ffio_get_checksum(bc));
320 static void write_mainheader(NUTContext *nut, AVIOContext *bc)
322 int i, j, tmp_pts, tmp_flags, tmp_stream, tmp_mul, tmp_size, tmp_fields,
326 ff_put_v(bc, NUT_VERSION);
327 ff_put_v(bc, nut->avf->nb_streams);
328 ff_put_v(bc, nut->max_distance);
329 ff_put_v(bc, nut->time_base_count);
331 for (i = 0; i < nut->time_base_count; i++) {
332 ff_put_v(bc, nut->time_base[i].num);
333 ff_put_v(bc, nut->time_base[i].den);
339 tmp_match = 1 - (1LL << 62);
341 for (i = 0; i < 256; ) {
345 if (tmp_pts != nut->frame_code[i].pts_delta)
347 if (tmp_mul != nut->frame_code[i].size_mul)
349 if (tmp_stream != nut->frame_code[i].stream_id)
351 if (tmp_size != nut->frame_code[i].size_lsb)
353 // if(tmp_res != nut->frame_code[i].res ) tmp_fields=5;
354 if (tmp_head_idx != nut->frame_code[i].header_idx)
357 tmp_pts = nut->frame_code[i].pts_delta;
358 tmp_flags = nut->frame_code[i].flags;
359 tmp_stream = nut->frame_code[i].stream_id;
360 tmp_mul = nut->frame_code[i].size_mul;
361 tmp_size = nut->frame_code[i].size_lsb;
362 // tmp_res = nut->frame_code[i].res;
363 tmp_head_idx = nut->frame_code[i].header_idx;
365 for (j = 0; i < 256; j++, i++) {
370 if (nut->frame_code[i].pts_delta != tmp_pts ||
371 nut->frame_code[i].flags != tmp_flags ||
372 nut->frame_code[i].stream_id != tmp_stream ||
373 nut->frame_code[i].size_mul != tmp_mul ||
374 nut->frame_code[i].size_lsb != tmp_size + j ||
375 // nut->frame_code[i].res != tmp_res ||
376 nut->frame_code[i].header_idx != tmp_head_idx)
379 if (j != tmp_mul - tmp_size)
382 ff_put_v(bc, tmp_flags);
383 ff_put_v(bc, tmp_fields);
387 ff_put_v(bc, tmp_mul);
389 ff_put_v(bc, tmp_stream);
391 ff_put_v(bc, tmp_size);
393 ff_put_v(bc, 0 /*tmp_res*/);
397 ff_put_v(bc, tmp_match);
399 ff_put_v(bc, tmp_head_idx);
401 ff_put_v(bc, nut->header_count - 1);
402 for (i = 1; i < nut->header_count; i++) {
403 ff_put_v(bc, nut->header_len[i]);
404 avio_write(bc, nut->header[i], nut->header_len[i]);
408 static int write_streamheader(AVFormatContext *avctx, AVIOContext *bc,
411 NUTContext *nut = avctx->priv_data;
412 AVCodecContext *codec = st->codec;
413 unsigned codec_tag = av_codec_get_tag(ff_nut_codec_tags, codec->codec_id);
416 switch (codec->codec_type) {
417 case AVMEDIA_TYPE_VIDEO:
420 case AVMEDIA_TYPE_AUDIO:
423 case AVMEDIA_TYPE_SUBTITLE:
432 if (!codec_tag || codec->codec_id == AV_CODEC_ID_RAWVIDEO)
433 codec_tag = codec->codec_tag;
436 avio_wl32(bc, codec_tag);
438 av_log(avctx, AV_LOG_ERROR, "No codec tag defined for stream %d\n", i);
439 return AVERROR(EINVAL);
442 ff_put_v(bc, nut->stream[i].time_base - nut->time_base);
443 ff_put_v(bc, nut->stream[i].msb_pts_shift);
444 ff_put_v(bc, nut->stream[i].max_pts_distance);
445 ff_put_v(bc, codec->has_b_frames);
446 avio_w8(bc, 0); /* flags: 0x1 - fixed_fps, 0x2 - index_present */
448 ff_put_v(bc, codec->extradata_size);
449 avio_write(bc, codec->extradata, codec->extradata_size);
451 switch (codec->codec_type) {
452 case AVMEDIA_TYPE_AUDIO:
453 ff_put_v(bc, codec->sample_rate);
455 ff_put_v(bc, codec->channels);
457 case AVMEDIA_TYPE_VIDEO:
458 ff_put_v(bc, codec->width);
459 ff_put_v(bc, codec->height);
461 if (st->sample_aspect_ratio.num <= 0 ||
462 st->sample_aspect_ratio.den <= 0) {
466 ff_put_v(bc, st->sample_aspect_ratio.num);
467 ff_put_v(bc, st->sample_aspect_ratio.den);
469 ff_put_v(bc, 0); /* csp type -- unknown */
477 static int add_info(AVIOContext *bc, const char *type, const char *value)
485 static int write_globalinfo(NUTContext *nut, AVIOContext *bc)
487 AVFormatContext *s = nut->avf;
488 AVDictionaryEntry *t = NULL;
490 uint8_t *dyn_buf = NULL;
491 int count = 0, dyn_size;
492 int ret = avio_open_dyn_buf(&dyn_bc);
496 while ((t = av_dict_get(s->metadata, "", t, AV_DICT_IGNORE_SUFFIX)))
497 count += add_info(dyn_bc, t->key, t->value);
499 ff_put_v(bc, 0); //stream_if_plus1
500 ff_put_v(bc, 0); //chapter_id
501 ff_put_v(bc, 0); //timestamp_start
502 ff_put_v(bc, 0); //length
506 dyn_size = avio_close_dyn_buf(dyn_bc, &dyn_buf);
507 avio_write(bc, dyn_buf, dyn_size);
512 static int write_streaminfo(NUTContext *nut, AVIOContext *bc, int stream_id){
513 AVFormatContext *s= nut->avf;
514 AVStream* st = s->streams[stream_id];
516 uint8_t *dyn_buf=NULL;
517 int count=0, dyn_size, i;
518 int ret = avio_open_dyn_buf(&dyn_bc);
522 for (i=0; ff_nut_dispositions[i].flag; ++i) {
523 if (st->disposition & ff_nut_dispositions[i].flag)
524 count += add_info(dyn_bc, "Disposition", ff_nut_dispositions[i].str);
526 dyn_size = avio_close_dyn_buf(dyn_bc, &dyn_buf);
529 ff_put_v(bc, stream_id + 1); //stream_id_plus1
530 ff_put_v(bc, 0); //chapter_id
531 ff_put_v(bc, 0); //timestamp_start
532 ff_put_v(bc, 0); //length
536 avio_write(bc, dyn_buf, dyn_size);
543 static int write_chapter(NUTContext *nut, AVIOContext *bc, int id)
546 uint8_t *dyn_buf = NULL;
547 AVDictionaryEntry *t = NULL;
548 AVChapter *ch = nut->avf->chapters[id];
549 int ret, dyn_size, count = 0;
551 ret = avio_open_dyn_buf(&dyn_bc);
555 ff_put_v(bc, 0); // stream_id_plus1
556 put_s(bc, id + 1); // chapter_id
557 put_tt(nut, nut->chapter[id].time_base, bc, ch->start); // chapter_start
558 ff_put_v(bc, ch->end - ch->start); // chapter_len
560 while ((t = av_dict_get(ch->metadata, "", t, AV_DICT_IGNORE_SUFFIX)))
561 count += add_info(dyn_bc, t->key, t->value);
565 dyn_size = avio_close_dyn_buf(dyn_bc, &dyn_buf);
566 avio_write(bc, dyn_buf, dyn_size);
571 static int write_headers(AVFormatContext *avctx, AVIOContext *bc)
573 NUTContext *nut = avctx->priv_data;
577 ff_metadata_conv_ctx(avctx, ff_nut_metadata_conv, NULL);
579 ret = avio_open_dyn_buf(&dyn_bc);
582 write_mainheader(nut, dyn_bc);
583 put_packet(nut, bc, dyn_bc, 1, MAIN_STARTCODE);
585 for (i = 0; i < nut->avf->nb_streams; i++) {
586 ret = avio_open_dyn_buf(&dyn_bc);
589 ret = write_streamheader(avctx, dyn_bc, nut->avf->streams[i], i);
592 put_packet(nut, bc, dyn_bc, 1, STREAM_STARTCODE);
595 ret = avio_open_dyn_buf(&dyn_bc);
598 write_globalinfo(nut, dyn_bc);
599 put_packet(nut, bc, dyn_bc, 1, INFO_STARTCODE);
601 for (i = 0; i < nut->avf->nb_streams; i++) {
602 ret = avio_open_dyn_buf(&dyn_bc);
605 ret = write_streaminfo(nut, dyn_bc, i);
609 put_packet(nut, bc, dyn_bc, 1, INFO_STARTCODE);
612 avio_close_dyn_buf(dyn_bc, &buf);
617 for (i = 0; i < nut->avf->nb_chapters; i++) {
618 ret = avio_open_dyn_buf(&dyn_bc);
621 ret = write_chapter(nut, dyn_bc, i);
624 avio_close_dyn_buf(dyn_bc, &buf);
628 put_packet(nut, bc, dyn_bc, 1, INFO_STARTCODE);
631 nut->last_syncpoint_pos = INT_MIN;
636 static int nut_write_header(AVFormatContext *s)
638 NUTContext *nut = s->priv_data;
639 AVIOContext *bc = s->pb;
644 nut->stream = av_mallocz(sizeof(StreamContext) * s->nb_streams);
646 nut->chapter = av_mallocz(sizeof(ChapterContext) * s->nb_chapters);
647 nut->time_base = av_mallocz(sizeof(AVRational) * (s->nb_streams +
649 if (!nut->stream || (s->nb_chapters && !nut->chapter) || !nut->time_base) {
650 av_freep(&nut->stream);
651 av_freep(&nut->chapter);
652 av_freep(&nut->time_base);
653 return AVERROR(ENOMEM);
656 for (i = 0; i < s->nb_streams; i++) {
657 AVStream *st = s->streams[i];
659 AVRational time_base;
660 ff_parse_specific_params(st->codec, &time_base.den, &ssize,
663 avpriv_set_pts_info(st, 64, time_base.num, time_base.den);
665 for (j = 0; j < nut->time_base_count; j++)
666 if (!memcmp(&time_base, &nut->time_base[j], sizeof(AVRational))) {
669 nut->time_base[j] = time_base;
670 nut->stream[i].time_base = &nut->time_base[j];
671 if (j == nut->time_base_count)
672 nut->time_base_count++;
674 if (INT64_C(1000) * time_base.num >= time_base.den)
675 nut->stream[i].msb_pts_shift = 7;
677 nut->stream[i].msb_pts_shift = 14;
678 nut->stream[i].max_pts_distance =
679 FFMAX(time_base.den, time_base.num) / time_base.num;
682 for (i = 0; i < s->nb_chapters; i++) {
683 AVChapter *ch = s->chapters[i];
685 for (j = 0; j < nut->time_base_count; j++)
686 if (!memcmp(&ch->time_base, &nut->time_base[j], sizeof(AVRational)))
689 nut->time_base[j] = ch->time_base;
690 nut->chapter[i].time_base = &nut->time_base[j];
691 if (j == nut->time_base_count)
692 nut->time_base_count++;
695 nut->max_distance = MAX_DISTANCE;
696 build_elision_headers(s);
698 assert(nut->frame_code['N'].flags == FLAG_INVALID);
700 avio_write(bc, ID_STRING, strlen(ID_STRING));
703 if ((ret = write_headers(s, bc)) < 0)
713 static int get_needed_flags(NUTContext *nut, StreamContext *nus, FrameCode *fc,
718 if (pkt->flags & AV_PKT_FLAG_KEY)
720 if (pkt->stream_index != fc->stream_id)
721 flags |= FLAG_STREAM_ID;
722 if (pkt->size / fc->size_mul)
723 flags |= FLAG_SIZE_MSB;
724 if (pkt->pts - nus->last_pts != fc->pts_delta)
725 flags |= FLAG_CODED_PTS;
726 if (pkt->size > 2 * nut->max_distance)
727 flags |= FLAG_CHECKSUM;
728 if (FFABS(pkt->pts - nus->last_pts) > nus->max_pts_distance)
729 flags |= FLAG_CHECKSUM;
730 if (pkt->size < nut->header_len[fc->header_idx] ||
731 (pkt->size > 4096 && fc->header_idx) ||
732 memcmp(pkt->data, nut->header[fc->header_idx],
733 nut->header_len[fc->header_idx]))
734 flags |= FLAG_HEADER_IDX;
736 return flags | (fc->flags & FLAG_CODED);
739 static int find_best_header_idx(NUTContext *nut, AVPacket *pkt)
745 if (pkt->size > 4096)
748 for (i = 1; i < nut->header_count; i++)
749 if (pkt->size >= nut->header_len[i]
750 && nut->header_len[i] > best_len
751 && !memcmp(pkt->data, nut->header[i], nut->header_len[i])) {
753 best_len = nut->header_len[i];
758 static int nut_write_packet(AVFormatContext *s, AVPacket *pkt)
760 NUTContext *nut = s->priv_data;
761 StreamContext *nus = &nut->stream[pkt->stream_index];
762 AVIOContext *bc = s->pb, *dyn_bc;
765 int best_length, frame_code, flags, needed_flags, i, header_idx,
767 int key_frame = !!(pkt->flags & AV_PKT_FLAG_KEY);
772 av_log(s, AV_LOG_ERROR,
773 "Negative pts not supported stream %d, pts %"PRId64"\n",
774 pkt->stream_index, pkt->pts);
775 return AVERROR_INVALIDDATA;
778 if (1LL << (20 + 3 * nut->header_count) <= avio_tell(bc))
779 write_headers(s, bc);
781 if (key_frame && !(nus->last_flags & FLAG_KEY))
784 if (pkt->size + 30 /*FIXME check*/ + avio_tell(bc) >=
785 nut->last_syncpoint_pos + nut->max_distance)
788 //FIXME: Ensure store_sp is 1 in the first place.
791 Syncpoint *sp, dummy = { .pos = INT64_MAX };
793 ff_nut_reset_ts(nut, *nus->time_base, pkt->dts);
794 for (i = 0; i < s->nb_streams; i++) {
795 AVStream *st = s->streams[i];
796 int64_t dts_tb = av_rescale_rnd(pkt->dts,
797 nus->time_base->num * (int64_t)nut->stream[i].time_base->den,
798 nus->time_base->den * (int64_t)nut->stream[i].time_base->num,
800 int index = av_index_search_timestamp(st, dts_tb,
801 AVSEEK_FLAG_BACKWARD);
803 dummy.pos = FFMIN(dummy.pos, st->index_entries[index].pos);
805 if (dummy.pos == INT64_MAX)
807 sp = av_tree_find(nut->syncpoints, &dummy, (void *)ff_nut_sp_pos_cmp,
810 nut->last_syncpoint_pos = avio_tell(bc);
811 ret = avio_open_dyn_buf(&dyn_bc);
814 put_tt(nut, nus->time_base, dyn_bc, pkt->dts);
815 ff_put_v(dyn_bc, sp ? (nut->last_syncpoint_pos - sp->pos) >> 4 : 0);
816 put_packet(nut, bc, dyn_bc, 1, SYNCPOINT_STARTCODE);
818 if ((ret = ff_nut_add_sp(nut, nut->last_syncpoint_pos, 0 /*unused*/, pkt->dts)) < 0)
821 assert(nus->last_pts != AV_NOPTS_VALUE);
823 coded_pts = pkt->pts & ((1 << nus->msb_pts_shift) - 1);
824 if (ff_lsb2full(nus, coded_pts) != pkt->pts)
825 coded_pts = pkt->pts + (1 << nus->msb_pts_shift);
827 best_header_idx = find_best_header_idx(nut, pkt);
829 best_length = INT_MAX;
831 for (i = 0; i < 256; i++) {
833 FrameCode *fc = &nut->frame_code[i];
834 int flags = fc->flags;
836 if (flags & FLAG_INVALID)
838 needed_flags = get_needed_flags(nut, nus, fc, pkt);
840 if (flags & FLAG_CODED) {
842 flags = needed_flags;
845 if ((flags & needed_flags) != needed_flags)
848 if ((flags ^ needed_flags) & FLAG_KEY)
851 if (flags & FLAG_STREAM_ID)
852 length += ff_get_v_length(pkt->stream_index);
854 if (pkt->size % fc->size_mul != fc->size_lsb)
856 if (flags & FLAG_SIZE_MSB)
857 length += ff_get_v_length(pkt->size / fc->size_mul);
859 if (flags & FLAG_CHECKSUM)
862 if (flags & FLAG_CODED_PTS)
863 length += ff_get_v_length(coded_pts);
865 if ((flags & FLAG_CODED)
866 && nut->header_len[best_header_idx] >
867 nut->header_len[fc->header_idx] + 1) {
868 flags |= FLAG_HEADER_IDX;
871 if (flags & FLAG_HEADER_IDX) {
872 length += 1 - nut->header_len[best_header_idx];
874 length -= nut->header_len[fc->header_idx];
878 length += !(flags & FLAG_CODED_PTS);
879 length += !(flags & FLAG_CHECKSUM);
881 if (length < best_length) {
882 best_length = length;
886 assert(frame_code != -1);
887 fc = &nut->frame_code[frame_code];
889 needed_flags = get_needed_flags(nut, nus, fc, pkt);
890 header_idx = fc->header_idx;
892 ffio_init_checksum(bc, ff_crc04C11DB7_update, 0);
893 avio_w8(bc, frame_code);
894 if (flags & FLAG_CODED) {
895 ff_put_v(bc, (flags ^ needed_flags) & ~(FLAG_CODED));
896 flags = needed_flags;
898 if (flags & FLAG_STREAM_ID)
899 ff_put_v(bc, pkt->stream_index);
900 if (flags & FLAG_CODED_PTS)
901 ff_put_v(bc, coded_pts);
902 if (flags & FLAG_SIZE_MSB)
903 ff_put_v(bc, pkt->size / fc->size_mul);
904 if (flags & FLAG_HEADER_IDX)
905 ff_put_v(bc, header_idx = best_header_idx);
907 if (flags & FLAG_CHECKSUM)
908 avio_wl32(bc, ffio_get_checksum(bc));
910 ffio_get_checksum(bc);
912 avio_write(bc, pkt->data + nut->header_len[header_idx],
913 pkt->size - nut->header_len[header_idx]);
914 nus->last_flags = flags;
915 nus->last_pts = pkt->pts;
917 //FIXME just store one per syncpoint
918 if (flags & FLAG_KEY)
920 s->streams[pkt->stream_index],
921 nut->last_syncpoint_pos,
930 static int nut_write_trailer(AVFormatContext *s)
932 NUTContext *nut = s->priv_data;
933 AVIOContext *bc = s->pb;
935 while (nut->header_count < 3)
936 write_headers(s, bc);
939 av_freep(&nut->stream);
940 av_freep(&nut->chapter);
941 av_freep(&nut->time_base);
946 AVOutputFormat ff_nut_muxer = {
948 .long_name = NULL_IF_CONFIG_SMALL("NUT"),
949 .mime_type = "video/x-nut",
951 .priv_data_size = sizeof(NUTContext),
952 .audio_codec = CONFIG_LIBVORBIS ? AV_CODEC_ID_VORBIS :
953 CONFIG_LIBMP3LAME ? AV_CODEC_ID_MP3 : AV_CODEC_ID_MP2,
954 .video_codec = AV_CODEC_ID_MPEG4,
955 .write_header = nut_write_header,
956 .write_packet = nut_write_packet,
957 .write_trailer = nut_write_trailer,
958 .flags = AVFMT_GLOBALHEADER | AVFMT_VARIABLE_FPS,
959 .codec_tag = ff_nut_codec_tags,