2 * "NUT" Container Format demuxer
3 * Copyright (c) 2004-2006 Michael Niedermayer
4 * Copyright (c) 2003 Alex Beregszaszi
6 * This file is part of FFmpeg.
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 #include "libavutil/avstring.h"
24 #include "libavutil/avassert.h"
25 #include "libavutil/bswap.h"
26 #include "libavutil/dict.h"
27 #include "libavutil/mathematics.h"
28 #include "libavutil/tree.h"
29 #include "avio_internal.h"
33 #define NUT_MAX_STREAMS 256 /* arbitrary sanity check value */
35 static int64_t nut_read_timestamp(AVFormatContext *s, int stream_index,
36 int64_t *pos_arg, int64_t pos_limit);
38 static int get_str(AVIOContext *bc, char *string, unsigned int maxlen)
40 unsigned int len = ffio_read_varlen(bc);
43 avio_read(bc, string, FFMIN(len, maxlen));
44 while (len > maxlen) {
50 string[FFMIN(len, maxlen - 1)] = 0;
58 static int64_t get_s(AVIOContext *bc)
60 int64_t v = ffio_read_varlen(bc) + 1;
68 static uint64_t get_fourcc(AVIOContext *bc)
70 unsigned int len = ffio_read_varlen(bc);
77 av_log(NULL, AV_LOG_ERROR, "Unsupported fourcc length %d\n", len);
83 static inline uint64_t get_v_trace(AVIOContext *bc, const char *file,
84 const char *func, int line)
86 uint64_t v = ffio_read_varlen(bc);
88 av_log(NULL, AV_LOG_DEBUG, "get_v %5"PRId64" / %"PRIX64" in %s %s:%d\n",
89 v, v, file, func, line);
93 static inline int64_t get_s_trace(AVIOContext *bc, const char *file,
94 const char *func, int line)
96 int64_t v = get_s(bc);
98 av_log(NULL, AV_LOG_DEBUG, "get_s %5"PRId64" / %"PRIX64" in %s %s:%d\n",
99 v, v, file, func, line);
103 static inline uint64_t get_4cc_trace(AVIOContext *bc, char *file,
104 char *func, int line)
106 uint64_t v = get_fourcc(bc);
108 av_log(NULL, AV_LOG_DEBUG, "get_fourcc %5"PRId64" / %"PRIX64" in %s %s:%d\n",
109 v, v, file, func, line);
112 #define ffio_read_varlen(bc) get_v_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
113 #define get_s(bc) get_s_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
114 #define get_fourcc(bc) get_4cc_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
117 static int get_packetheader(NUTContext *nut, AVIOContext *bc,
118 int calculate_checksum, uint64_t startcode)
121 // start = avio_tell(bc) - 8;
123 startcode = av_be2ne64(startcode);
124 startcode = ff_crc04C11DB7_update(0, (uint8_t*) &startcode, 8);
126 ffio_init_checksum(bc, ff_crc04C11DB7_update, startcode);
127 size = ffio_read_varlen(bc);
130 if (ffio_get_checksum(bc) && size > 4096)
133 ffio_init_checksum(bc, calculate_checksum ? ff_crc04C11DB7_update : NULL, 0);
138 static uint64_t find_any_startcode(AVIOContext *bc, int64_t pos)
143 /* Note, this may fail if the stream is not seekable, but that should
144 * not matter, as in this case we simply start where we currently are */
145 avio_seek(bc, pos, SEEK_SET);
146 while (!url_feof(bc)) {
147 state = (state << 8) | avio_r8(bc);
148 if ((state >> 56) != 'N')
152 case STREAM_STARTCODE:
153 case SYNCPOINT_STARTCODE:
155 case INDEX_STARTCODE:
164 * Find the given startcode.
165 * @param code the startcode
166 * @param pos the start position of the search, or -1 if the current position
167 * @return the position of the startcode or -1 if not found
169 static int64_t find_startcode(AVIOContext *bc, uint64_t code, int64_t pos)
172 uint64_t startcode = find_any_startcode(bc, pos);
173 if (startcode == code)
174 return avio_tell(bc) - 8;
175 else if (startcode == 0)
181 static int nut_probe(AVProbeData *p)
186 for (i = 0; i < p->buf_size; i++) {
187 code = (code << 8) | p->buf[i];
188 if (code == MAIN_STARTCODE)
189 return AVPROBE_SCORE_MAX;
194 #define GET_V(dst, check) \
196 tmp = ffio_read_varlen(bc); \
198 av_log(s, AV_LOG_ERROR, "Error " #dst " is (%"PRId64")\n", tmp); \
199 return AVERROR_INVALIDDATA; \
204 static int skip_reserved(AVIOContext *bc, int64_t pos)
206 pos -= avio_tell(bc);
208 avio_seek(bc, pos, SEEK_CUR);
209 return AVERROR_INVALIDDATA;
217 static int decode_main_header(NUTContext *nut)
219 AVFormatContext *s = nut->avf;
220 AVIOContext *bc = s->pb;
222 unsigned int stream_count;
224 int tmp_stream, tmp_mul, tmp_pts, tmp_size, tmp_res, tmp_head_idx;
226 end = get_packetheader(nut, bc, 1, MAIN_STARTCODE);
227 end += avio_tell(bc);
229 tmp = ffio_read_varlen(bc);
230 if (tmp < 2 && tmp > NUT_VERSION) {
231 av_log(s, AV_LOG_ERROR, "Version %"PRId64" not supported.\n",
233 return AVERROR(ENOSYS);
236 GET_V(stream_count, tmp > 0 && tmp <= NUT_MAX_STREAMS);
238 nut->max_distance = ffio_read_varlen(bc);
239 if (nut->max_distance > 65536) {
240 av_log(s, AV_LOG_DEBUG, "max_distance %d\n", nut->max_distance);
241 nut->max_distance = 65536;
244 GET_V(nut->time_base_count, tmp > 0 && tmp < INT_MAX / sizeof(AVRational));
245 nut->time_base = av_malloc(nut->time_base_count * sizeof(AVRational));
247 return AVERROR(ENOMEM);
249 for (i = 0; i < nut->time_base_count; i++) {
250 GET_V(nut->time_base[i].num, tmp > 0 && tmp < (1ULL << 31));
251 GET_V(nut->time_base[i].den, tmp > 0 && tmp < (1ULL << 31));
252 if (av_gcd(nut->time_base[i].num, nut->time_base[i].den) != 1) {
253 av_log(s, AV_LOG_ERROR, "time base invalid\n");
254 return AVERROR_INVALIDDATA;
261 for (i = 0; i < 256;) {
262 int tmp_flags = ffio_read_varlen(bc);
263 int tmp_fields = ffio_read_varlen(bc);
268 tmp_mul = ffio_read_varlen(bc);
270 tmp_stream = ffio_read_varlen(bc);
272 tmp_size = ffio_read_varlen(bc);
276 tmp_res = ffio_read_varlen(bc);
280 count = ffio_read_varlen(bc);
282 count = tmp_mul - tmp_size;
286 tmp_head_idx = ffio_read_varlen(bc);
288 while (tmp_fields-- > 8)
289 ffio_read_varlen(bc);
291 if (count == 0 || i + count > 256) {
292 av_log(s, AV_LOG_ERROR, "illegal count %d at %d\n", count, i);
293 return AVERROR_INVALIDDATA;
295 if (tmp_stream >= stream_count) {
296 av_log(s, AV_LOG_ERROR, "illegal stream number\n");
297 return AVERROR_INVALIDDATA;
300 for (j = 0; j < count; j++, i++) {
302 nut->frame_code[i].flags = FLAG_INVALID;
306 nut->frame_code[i].flags = tmp_flags;
307 nut->frame_code[i].pts_delta = tmp_pts;
308 nut->frame_code[i].stream_id = tmp_stream;
309 nut->frame_code[i].size_mul = tmp_mul;
310 nut->frame_code[i].size_lsb = tmp_size + j;
311 nut->frame_code[i].reserved_count = tmp_res;
312 nut->frame_code[i].header_idx = tmp_head_idx;
315 av_assert0(nut->frame_code['N'].flags == FLAG_INVALID);
317 if (end > avio_tell(bc) + 4) {
319 GET_V(nut->header_count, tmp < 128U);
321 for (i = 1; i < nut->header_count; i++) {
323 GET_V(nut->header_len[i], tmp > 0 && tmp < 256);
324 rem -= nut->header_len[i];
326 av_log(s, AV_LOG_ERROR, "invalid elision header\n");
327 return AVERROR_INVALIDDATA;
329 hdr = av_malloc(nut->header_len[i]);
331 return AVERROR(ENOMEM);
332 avio_read(bc, hdr, nut->header_len[i]);
333 nut->header[i] = hdr;
335 av_assert0(nut->header_len[0] == 0);
338 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
339 av_log(s, AV_LOG_ERROR, "main header checksum mismatch\n");
340 return AVERROR_INVALIDDATA;
343 nut->stream = av_calloc(stream_count, sizeof(StreamContext));
345 return AVERROR(ENOMEM);
346 for (i = 0; i < stream_count; i++)
347 avformat_new_stream(s, NULL);
352 static int decode_stream_header(NUTContext *nut)
354 AVFormatContext *s = nut->avf;
355 AVIOContext *bc = s->pb;
357 int class, stream_id;
361 end = get_packetheader(nut, bc, 1, STREAM_STARTCODE);
362 end += avio_tell(bc);
364 GET_V(stream_id, tmp < s->nb_streams && !nut->stream[tmp].time_base);
365 stc = &nut->stream[stream_id];
366 st = s->streams[stream_id];
368 return AVERROR(ENOMEM);
370 class = ffio_read_varlen(bc);
371 tmp = get_fourcc(bc);
372 st->codec->codec_tag = tmp;
375 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
376 st->codec->codec_id = av_codec_get_id((const AVCodecTag * const []) {
384 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
385 st->codec->codec_id = av_codec_get_id((const AVCodecTag * const []) {
393 st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
394 st->codec->codec_id = ff_codec_get_id(ff_nut_subtitle_tags, tmp);
397 st->codec->codec_type = AVMEDIA_TYPE_DATA;
398 st->codec->codec_id = ff_codec_get_id(ff_nut_data_tags, tmp);
401 av_log(s, AV_LOG_ERROR, "unknown stream class (%d)\n", class);
402 return AVERROR(ENOSYS);
404 if (class < 3 && st->codec->codec_id == AV_CODEC_ID_NONE)
405 av_log(s, AV_LOG_ERROR,
406 "Unknown codec tag '0x%04x' for stream number %d\n",
407 (unsigned int) tmp, stream_id);
409 GET_V(stc->time_base_id, tmp < nut->time_base_count);
410 GET_V(stc->msb_pts_shift, tmp < 16);
411 stc->max_pts_distance = ffio_read_varlen(bc);
412 GET_V(stc->decode_delay, tmp < 1000); // sanity limit, raise this if Moore's law is true
413 st->codec->has_b_frames = stc->decode_delay;
414 ffio_read_varlen(bc); // stream flags
416 GET_V(st->codec->extradata_size, tmp < (1 << 30));
417 if (st->codec->extradata_size) {
418 if (ff_alloc_extradata(st->codec, st->codec->extradata_size))
419 return AVERROR(ENOMEM);
420 avio_read(bc, st->codec->extradata, st->codec->extradata_size);
423 if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
424 GET_V(st->codec->width, tmp > 0);
425 GET_V(st->codec->height, tmp > 0);
426 st->sample_aspect_ratio.num = ffio_read_varlen(bc);
427 st->sample_aspect_ratio.den = ffio_read_varlen(bc);
428 if ((!st->sample_aspect_ratio.num) != (!st->sample_aspect_ratio.den)) {
429 av_log(s, AV_LOG_ERROR, "invalid aspect ratio %d/%d\n",
430 st->sample_aspect_ratio.num, st->sample_aspect_ratio.den);
431 return AVERROR_INVALIDDATA;
433 ffio_read_varlen(bc); /* csp type */
434 } else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
435 GET_V(st->codec->sample_rate, tmp > 0);
436 ffio_read_varlen(bc); // samplerate_den
437 GET_V(st->codec->channels, tmp > 0);
439 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
440 av_log(s, AV_LOG_ERROR,
441 "stream header %d checksum mismatch\n", stream_id);
442 return AVERROR_INVALIDDATA;
444 stc->time_base = &nut->time_base[stc->time_base_id];
445 avpriv_set_pts_info(s->streams[stream_id], 63, stc->time_base->num,
446 stc->time_base->den);
450 static void set_disposition_bits(AVFormatContext *avf, char *value,
455 for (i = 0; ff_nut_dispositions[i].flag; ++i)
456 if (!strcmp(ff_nut_dispositions[i].str, value))
457 flag = ff_nut_dispositions[i].flag;
459 av_log(avf, AV_LOG_INFO, "unknown disposition type '%s'\n", value);
460 for (i = 0; i < avf->nb_streams; ++i)
461 if (stream_id == i || stream_id == -1)
462 avf->streams[i]->disposition |= flag;
465 static int decode_info_header(NUTContext *nut)
467 AVFormatContext *s = nut->avf;
468 AVIOContext *bc = s->pb;
469 uint64_t tmp, chapter_start, chapter_len;
470 unsigned int stream_id_plus1, count;
473 char name[256], str_value[1024], type_str[256];
475 AVChapter *chapter = NULL;
477 AVDictionary **metadata = NULL;
479 end = get_packetheader(nut, bc, 1, INFO_STARTCODE);
480 end += avio_tell(bc);
482 GET_V(stream_id_plus1, tmp <= s->nb_streams);
483 chapter_id = get_s(bc);
484 chapter_start = ffio_read_varlen(bc);
485 chapter_len = ffio_read_varlen(bc);
486 count = ffio_read_varlen(bc);
488 if (chapter_id && !stream_id_plus1) {
489 int64_t start = chapter_start / nut->time_base_count;
490 chapter = avpriv_new_chapter(s, chapter_id,
491 nut->time_base[chapter_start %
492 nut->time_base_count],
493 start, start + chapter_len, NULL);
494 metadata = &chapter->metadata;
495 } else if (stream_id_plus1) {
496 st = s->streams[stream_id_plus1 - 1];
497 metadata = &st->metadata;
499 metadata = &s->metadata;
501 for (i = 0; i < count; i++) {
502 get_str(bc, name, sizeof(name));
506 get_str(bc, str_value, sizeof(str_value));
507 } else if (value == -2) {
508 get_str(bc, type_str, sizeof(type_str));
510 get_str(bc, str_value, sizeof(str_value));
511 } else if (value == -3) {
514 } else if (value == -4) {
516 value = ffio_read_varlen(bc);
517 } else if (value < -4) {
524 if (stream_id_plus1 > s->nb_streams) {
525 av_log(s, AV_LOG_ERROR, "invalid stream id for info packet\n");
529 if (!strcmp(type, "UTF-8")) {
530 if (chapter_id == 0 && !strcmp(name, "Disposition")) {
531 set_disposition_bits(s, str_value, stream_id_plus1 - 1);
535 if (stream_id_plus1 && !strcmp(name, "r_frame_rate")) {
536 sscanf(str_value, "%d/%d", &st->r_frame_rate.num, &st->r_frame_rate.den);
537 if (st->r_frame_rate.num >= 1000LL*st->r_frame_rate.den)
538 st->r_frame_rate.num = st->r_frame_rate.den = 0;
542 if (metadata && av_strcasecmp(name, "Uses") &&
543 av_strcasecmp(name, "Depends") && av_strcasecmp(name, "Replaces"))
544 av_dict_set(metadata, name, str_value, 0);
548 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
549 av_log(s, AV_LOG_ERROR, "info header checksum mismatch\n");
550 return AVERROR_INVALIDDATA;
555 static int decode_syncpoint(NUTContext *nut, int64_t *ts, int64_t *back_ptr)
557 AVFormatContext *s = nut->avf;
558 AVIOContext *bc = s->pb;
562 nut->last_syncpoint_pos = avio_tell(bc) - 8;
564 end = get_packetheader(nut, bc, 1, SYNCPOINT_STARTCODE);
565 end += avio_tell(bc);
567 tmp = ffio_read_varlen(bc);
568 *back_ptr = nut->last_syncpoint_pos - 16 * ffio_read_varlen(bc);
570 return AVERROR_INVALIDDATA;
572 ff_nut_reset_ts(nut, nut->time_base[tmp % nut->time_base_count],
573 tmp / nut->time_base_count);
575 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
576 av_log(s, AV_LOG_ERROR, "sync point checksum mismatch\n");
577 return AVERROR_INVALIDDATA;
580 *ts = tmp / nut->time_base_count *
581 av_q2d(nut->time_base[tmp % nut->time_base_count]) * AV_TIME_BASE;
582 ff_nut_add_sp(nut, nut->last_syncpoint_pos, *back_ptr, *ts);
587 //FIXME calculate exactly, this is just a good approximation.
588 static int64_t find_duration(NUTContext *nut, int64_t filesize)
590 AVFormatContext *s = nut->avf;
591 int64_t duration = 0;
593 ff_find_last_ts(s, -1, &duration, NULL, nut_read_timestamp);
596 s->duration_estimation_method = AVFMT_DURATION_FROM_PTS;
600 static int find_and_decode_index(NUTContext *nut)
602 AVFormatContext *s = nut->avf;
603 AVIOContext *bc = s->pb;
605 int i, j, syncpoint_count;
606 int64_t filesize = avio_size(bc);
609 int8_t *has_keyframe;
610 int ret = AVERROR_INVALIDDATA;
615 avio_seek(bc, filesize - 12, SEEK_SET);
616 avio_seek(bc, filesize - avio_rb64(bc), SEEK_SET);
617 if (avio_rb64(bc) != INDEX_STARTCODE) {
618 av_log(s, AV_LOG_ERROR, "no index at the end\n");
621 s->duration = find_duration(nut, filesize);
625 end = get_packetheader(nut, bc, 1, INDEX_STARTCODE);
626 end += avio_tell(bc);
628 max_pts = ffio_read_varlen(bc);
629 s->duration = av_rescale_q(max_pts / nut->time_base_count,
630 nut->time_base[max_pts % nut->time_base_count],
632 s->duration_estimation_method = AVFMT_DURATION_FROM_PTS;
634 GET_V(syncpoint_count, tmp < INT_MAX / 8 && tmp > 0);
635 syncpoints = av_malloc_array(syncpoint_count, sizeof(int64_t));
636 has_keyframe = av_malloc_array(syncpoint_count + 1, sizeof(int8_t));
637 if (!syncpoints || !has_keyframe) {
638 ret = AVERROR(ENOMEM);
641 for (i = 0; i < syncpoint_count; i++) {
642 syncpoints[i] = ffio_read_varlen(bc);
643 if (syncpoints[i] <= 0)
646 syncpoints[i] += syncpoints[i - 1];
649 for (i = 0; i < s->nb_streams; i++) {
650 int64_t last_pts = -1;
651 for (j = 0; j < syncpoint_count;) {
652 uint64_t x = ffio_read_varlen(bc);
659 if (n + x >= syncpoint_count + 1) {
660 av_log(s, AV_LOG_ERROR, "index overflow A %d + %"PRIu64" >= %d\n", n, x, syncpoint_count + 1);
664 has_keyframe[n++] = flag;
665 has_keyframe[n++] = !flag;
668 if (n >= syncpoint_count + 1) {
669 av_log(s, AV_LOG_ERROR, "index overflow B\n");
672 has_keyframe[n++] = x & 1;
676 if (has_keyframe[0]) {
677 av_log(s, AV_LOG_ERROR, "keyframe before first syncpoint in index\n");
680 av_assert0(n <= syncpoint_count + 1);
681 for (; j < n && j < syncpoint_count; j++) {
682 if (has_keyframe[j]) {
683 uint64_t B, A = ffio_read_varlen(bc);
685 A = ffio_read_varlen(bc);
686 B = ffio_read_varlen(bc);
687 // eor_pts[j][i] = last_pts + A + B
690 av_add_index_entry(s->streams[i], 16 * syncpoints[j - 1],
691 last_pts + A, 0, 0, AVINDEX_KEYFRAME);
698 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
699 av_log(s, AV_LOG_ERROR, "index checksum mismatch\n");
706 av_free(has_keyframe);
710 static int nut_read_header(AVFormatContext *s)
712 NUTContext *nut = s->priv_data;
713 AVIOContext *bc = s->pb;
715 int initialized_stream_count;
722 pos = find_startcode(bc, MAIN_STARTCODE, pos) + 1;
724 av_log(s, AV_LOG_ERROR, "No main startcode found.\n");
725 return AVERROR_INVALIDDATA;
727 } while (decode_main_header(nut) < 0);
731 for (initialized_stream_count = 0; initialized_stream_count < s->nb_streams;) {
732 pos = find_startcode(bc, STREAM_STARTCODE, pos) + 1;
734 av_log(s, AV_LOG_ERROR, "Not all stream headers found.\n");
735 return AVERROR_INVALIDDATA;
737 if (decode_stream_header(nut) >= 0)
738 initialized_stream_count++;
744 uint64_t startcode = find_any_startcode(bc, pos);
747 if (startcode == 0) {
748 av_log(s, AV_LOG_ERROR, "EOF before video frames\n");
749 return AVERROR_INVALIDDATA;
750 } else if (startcode == SYNCPOINT_STARTCODE) {
751 nut->next_startcode = startcode;
753 } else if (startcode != INFO_STARTCODE) {
757 decode_info_header(nut);
760 s->data_offset = pos - 8;
763 int64_t orig_pos = avio_tell(bc);
764 find_and_decode_index(nut);
765 avio_seek(bc, orig_pos, SEEK_SET);
767 av_assert0(nut->next_startcode == SYNCPOINT_STARTCODE);
769 ff_metadata_conv_ctx(s, NULL, ff_nut_metadata_conv);
774 static int decode_frame_header(NUTContext *nut, int64_t *pts, int *stream_id,
775 uint8_t *header_idx, int frame_code)
777 AVFormatContext *s = nut->avf;
778 AVIOContext *bc = s->pb;
780 int size, flags, size_mul, pts_delta, i, reserved_count;
783 if (avio_tell(bc) > nut->last_syncpoint_pos + nut->max_distance) {
784 av_log(s, AV_LOG_ERROR,
785 "Last frame must have been damaged %"PRId64" > %"PRId64" + %d\n",
786 avio_tell(bc), nut->last_syncpoint_pos, nut->max_distance);
787 return AVERROR_INVALIDDATA;
790 flags = nut->frame_code[frame_code].flags;
791 size_mul = nut->frame_code[frame_code].size_mul;
792 size = nut->frame_code[frame_code].size_lsb;
793 *stream_id = nut->frame_code[frame_code].stream_id;
794 pts_delta = nut->frame_code[frame_code].pts_delta;
795 reserved_count = nut->frame_code[frame_code].reserved_count;
796 *header_idx = nut->frame_code[frame_code].header_idx;
798 if (flags & FLAG_INVALID)
799 return AVERROR_INVALIDDATA;
800 if (flags & FLAG_CODED)
801 flags ^= ffio_read_varlen(bc);
802 if (flags & FLAG_STREAM_ID) {
803 GET_V(*stream_id, tmp < s->nb_streams);
805 stc = &nut->stream[*stream_id];
806 if (flags & FLAG_CODED_PTS) {
807 int coded_pts = ffio_read_varlen(bc);
808 // FIXME check last_pts validity?
809 if (coded_pts < (1 << stc->msb_pts_shift)) {
810 *pts = ff_lsb2full(stc, coded_pts);
812 *pts = coded_pts - (1LL << stc->msb_pts_shift);
814 *pts = stc->last_pts + pts_delta;
815 if (flags & FLAG_SIZE_MSB)
816 size += size_mul * ffio_read_varlen(bc);
817 if (flags & FLAG_MATCH_TIME)
819 if (flags & FLAG_HEADER_IDX)
820 *header_idx = ffio_read_varlen(bc);
821 if (flags & FLAG_RESERVED)
822 reserved_count = ffio_read_varlen(bc);
823 for (i = 0; i < reserved_count; i++)
824 ffio_read_varlen(bc);
826 if (*header_idx >= (unsigned)nut->header_count) {
827 av_log(s, AV_LOG_ERROR, "header_idx invalid\n");
828 return AVERROR_INVALIDDATA;
832 size -= nut->header_len[*header_idx];
834 if (flags & FLAG_CHECKSUM) {
835 avio_rb32(bc); // FIXME check this
836 } else if (size > 2 * nut->max_distance || FFABS(stc->last_pts - *pts) >
837 stc->max_pts_distance) {
838 av_log(s, AV_LOG_ERROR, "frame size > 2max_distance and no checksum\n");
839 return AVERROR_INVALIDDATA;
842 stc->last_pts = *pts;
843 stc->last_flags = flags;
848 static int decode_frame(NUTContext *nut, AVPacket *pkt, int frame_code)
850 AVFormatContext *s = nut->avf;
851 AVIOContext *bc = s->pb;
852 int size, stream_id, discard;
853 int64_t pts, last_IP_pts;
857 size = decode_frame_header(nut, &pts, &stream_id, &header_idx, frame_code);
861 stc = &nut->stream[stream_id];
863 if (stc->last_flags & FLAG_KEY)
864 stc->skip_until_key_frame = 0;
866 discard = s->streams[stream_id]->discard;
867 last_IP_pts = s->streams[stream_id]->last_IP_pts;
868 if ((discard >= AVDISCARD_NONKEY && !(stc->last_flags & FLAG_KEY)) ||
869 (discard >= AVDISCARD_BIDIR && last_IP_pts != AV_NOPTS_VALUE &&
870 last_IP_pts > pts) ||
871 discard >= AVDISCARD_ALL ||
872 stc->skip_until_key_frame) {
877 if (av_new_packet(pkt, size + nut->header_len[header_idx]) < 0)
878 return AVERROR(ENOMEM);
879 memcpy(pkt->data, nut->header[header_idx], nut->header_len[header_idx]);
880 pkt->pos = avio_tell(bc); // FIXME
881 avio_read(bc, pkt->data + nut->header_len[header_idx], size);
883 pkt->stream_index = stream_id;
884 if (stc->last_flags & FLAG_KEY)
885 pkt->flags |= AV_PKT_FLAG_KEY;
891 static int nut_read_packet(AVFormatContext *s, AVPacket *pkt)
893 NUTContext *nut = s->priv_data;
894 AVIOContext *bc = s->pb;
895 int i, frame_code = 0, ret, skip;
896 int64_t ts, back_ptr;
899 int64_t pos = avio_tell(bc);
900 uint64_t tmp = nut->next_startcode;
901 nut->next_startcode = 0;
906 frame_code = avio_r8(bc);
909 if (frame_code == 'N') {
911 for (i = 1; i < 8; i++)
912 tmp = (tmp << 8) + avio_r8(bc);
917 case STREAM_STARTCODE:
918 case INDEX_STARTCODE:
919 skip = get_packetheader(nut, bc, 0, tmp);
923 if (decode_info_header(nut) < 0)
926 case SYNCPOINT_STARTCODE:
927 if (decode_syncpoint(nut, &ts, &back_ptr) < 0)
929 frame_code = avio_r8(bc);
931 ret = decode_frame(nut, pkt, frame_code);
934 else if (ret == 1) // OK but discard packet
938 av_log(s, AV_LOG_DEBUG, "syncing from %"PRId64"\n", pos);
939 tmp = find_any_startcode(bc, nut->last_syncpoint_pos + 1);
941 return AVERROR_INVALIDDATA;
942 av_log(s, AV_LOG_DEBUG, "sync\n");
943 nut->next_startcode = tmp;
948 static int64_t nut_read_timestamp(AVFormatContext *s, int stream_index,
949 int64_t *pos_arg, int64_t pos_limit)
951 NUTContext *nut = s->priv_data;
952 AVIOContext *bc = s->pb;
953 int64_t pos, pts, back_ptr;
954 av_log(s, AV_LOG_DEBUG, "read_timestamp(X,%d,%"PRId64",%"PRId64")\n",
955 stream_index, *pos_arg, pos_limit);
959 pos = find_startcode(bc, SYNCPOINT_STARTCODE, pos) + 1;
961 av_log(s, AV_LOG_ERROR, "read_timestamp failed.\n");
962 return AV_NOPTS_VALUE;
964 } while (decode_syncpoint(nut, &pts, &back_ptr) < 0);
966 av_assert0(nut->last_syncpoint_pos == *pos_arg);
968 av_log(s, AV_LOG_DEBUG, "return %"PRId64" %"PRId64"\n", pts, back_ptr);
969 if (stream_index == -2)
971 av_assert0(stream_index == -1);
975 static int read_seek(AVFormatContext *s, int stream_index,
976 int64_t pts, int flags)
978 NUTContext *nut = s->priv_data;
979 AVStream *st = s->streams[stream_index];
980 Syncpoint dummy = { .ts = pts * av_q2d(st->time_base) * AV_TIME_BASE };
981 Syncpoint nopts_sp = { .ts = AV_NOPTS_VALUE, .back_ptr = AV_NOPTS_VALUE };
982 Syncpoint *sp, *next_node[2] = { &nopts_sp, &nopts_sp };
983 int64_t pos, pos2, ts;
986 if (st->index_entries) {
987 int index = av_index_search_timestamp(st, pts, flags);
989 index = av_index_search_timestamp(st, pts, flags ^ AVSEEK_FLAG_BACKWARD);
993 pos2 = st->index_entries[index].pos;
994 ts = st->index_entries[index].timestamp;
996 av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pts_cmp,
997 (void **) next_node);
998 av_log(s, AV_LOG_DEBUG, "%"PRIu64"-%"PRIu64" %"PRId64"-%"PRId64"\n",
999 next_node[0]->pos, next_node[1]->pos, next_node[0]->ts,
1001 pos = ff_gen_search(s, -1, dummy.ts, next_node[0]->pos,
1002 next_node[1]->pos, next_node[1]->pos,
1003 next_node[0]->ts, next_node[1]->ts,
1004 AVSEEK_FLAG_BACKWARD, &ts, nut_read_timestamp);
1006 if (!(flags & AVSEEK_FLAG_BACKWARD)) {
1007 dummy.pos = pos + 16;
1008 next_node[1] = &nopts_sp;
1009 av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp,
1010 (void **) next_node);
1011 pos2 = ff_gen_search(s, -2, dummy.pos, next_node[0]->pos,
1012 next_node[1]->pos, next_node[1]->pos,
1013 next_node[0]->back_ptr, next_node[1]->back_ptr,
1014 flags, &ts, nut_read_timestamp);
1017 // FIXME dir but I think it does not matter
1020 sp = av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp,
1024 pos2 = sp->back_ptr - 15;
1026 av_log(NULL, AV_LOG_DEBUG, "SEEKTO: %"PRId64"\n", pos2);
1027 pos = find_startcode(s->pb, SYNCPOINT_STARTCODE, pos2);
1028 avio_seek(s->pb, pos, SEEK_SET);
1029 av_log(NULL, AV_LOG_DEBUG, "SP: %"PRId64"\n", pos);
1030 if (pos2 > pos || pos2 + 15 < pos)
1031 av_log(NULL, AV_LOG_ERROR, "no syncpoint at backptr pos\n");
1032 for (i = 0; i < s->nb_streams; i++)
1033 nut->stream[i].skip_until_key_frame = 1;
1038 static int nut_read_close(AVFormatContext *s)
1040 NUTContext *nut = s->priv_data;
1043 av_freep(&nut->time_base);
1044 av_freep(&nut->stream);
1045 ff_nut_free_sp(nut);
1046 for (i = 1; i < nut->header_count; i++)
1047 av_freep(&nut->header[i]);
1052 AVInputFormat ff_nut_demuxer = {
1054 .long_name = NULL_IF_CONFIG_SMALL("NUT"),
1055 .flags = AVFMT_SEEK_TO_PTS,
1056 .priv_data_size = sizeof(NUTContext),
1057 .read_probe = nut_probe,
1058 .read_header = nut_read_header,
1059 .read_packet = nut_read_packet,
1060 .read_close = nut_read_close,
1061 .read_seek = read_seek,
1062 .extensions = "nut",
1063 .codec_tag = ff_nut_codec_tags,