2 * "NUT" Container Format demuxer
3 * Copyright (c) 2004-2006 Michael Niedermayer
4 * Copyright (c) 2003 Alex Beregszaszi
6 * This file is part of Libav.
8 * Libav 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 * Libav 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 Libav; 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/bswap.h"
25 #include "libavutil/dict.h"
26 #include "libavutil/mathematics.h"
27 #include "libavutil/tree.h"
28 #include "avio_internal.h"
35 #define NUT_MAX_STREAMS 256 /* arbitrary sanity check value */
37 static int get_str(AVIOContext *bc, char *string, unsigned int maxlen)
39 unsigned int len = ffio_read_varlen(bc);
42 avio_read(bc, string, FFMIN(len, maxlen));
43 while (len > maxlen) {
49 string[FFMIN(len, maxlen - 1)] = 0;
57 static int64_t get_s(AVIOContext *bc)
59 int64_t v = ffio_read_varlen(bc) + 1;
67 static uint64_t get_fourcc(AVIOContext *bc)
69 unsigned int len = ffio_read_varlen(bc);
80 static inline uint64_t get_v_trace(AVIOContext *bc, const char *file,
81 const char *func, int line)
83 uint64_t v = ffio_read_varlen(bc);
85 av_log(NULL, AV_LOG_DEBUG, "get_v %5"PRId64" / %"PRIX64" in %s %s:%d\n",
86 v, v, file, func, line);
90 static inline int64_t get_s_trace(AVIOContext *bc, const char *file,
91 const char *func, int line)
93 int64_t v = get_s(bc);
95 av_log(NULL, AV_LOG_DEBUG, "get_s %5"PRId64" / %"PRIX64" in %s %s:%d\n",
96 v, v, file, func, line);
100 #define ffio_read_varlen(bc) get_v_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
101 #define get_s(bc) get_s_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
104 static int get_packetheader(NUTContext *nut, AVIOContext *bc,
105 int calculate_checksum, uint64_t startcode)
108 // start = avio_tell(bc) - 8;
110 startcode = av_be2ne64(startcode);
111 startcode = ff_crc04C11DB7_update(0, (uint8_t*) &startcode, 8);
113 ffio_init_checksum(bc, ff_crc04C11DB7_update, startcode);
114 size = ffio_read_varlen(bc);
117 if (ffio_get_checksum(bc) && size > 4096)
120 ffio_init_checksum(bc, calculate_checksum ? ff_crc04C11DB7_update : NULL, 0);
125 static uint64_t find_any_startcode(AVIOContext *bc, int64_t pos)
130 /* Note, this may fail if the stream is not seekable, but that should
131 * not matter, as in this case we simply start where we currently are */
132 avio_seek(bc, pos, SEEK_SET);
133 while (!bc->eof_reached) {
134 state = (state << 8) | avio_r8(bc);
135 if ((state >> 56) != 'N')
139 case STREAM_STARTCODE:
140 case SYNCPOINT_STARTCODE:
142 case INDEX_STARTCODE:
151 * Find the given startcode.
152 * @param code the startcode
153 * @param pos the start position of the search, or -1 if the current position
154 * @return the position of the startcode or -1 if not found
156 static int64_t find_startcode(AVIOContext *bc, uint64_t code, int64_t pos)
159 uint64_t startcode = find_any_startcode(bc, pos);
160 if (startcode == code)
161 return avio_tell(bc) - 8;
162 else if (startcode == 0)
168 static int nut_probe(AVProbeData *p)
173 for (i = 0; i < p->buf_size; i++) {
174 code = (code << 8) | p->buf[i];
175 if (code == MAIN_STARTCODE)
176 return AVPROBE_SCORE_MAX;
181 #define GET_V(dst, check) \
183 tmp = ffio_read_varlen(bc); \
185 av_log(s, AV_LOG_ERROR, "Error " #dst " is (%"PRId64")\n", tmp); \
186 return AVERROR_INVALIDDATA; \
191 static int skip_reserved(AVIOContext *bc, int64_t pos)
193 pos -= avio_tell(bc);
195 avio_seek(bc, pos, SEEK_CUR);
196 return AVERROR_INVALIDDATA;
204 static int decode_main_header(NUTContext *nut)
206 AVFormatContext *s = nut->avf;
207 AVIOContext *bc = s->pb;
209 unsigned int stream_count;
211 int tmp_stream, tmp_mul, tmp_pts, tmp_size, tmp_res, tmp_head_idx;
213 end = get_packetheader(nut, bc, 1, MAIN_STARTCODE);
214 end += avio_tell(bc);
216 nut->version = ffio_read_varlen(bc);
217 if (nut->version < NUT_MIN_VERSION &&
218 nut->version > NUT_MAX_VERSION) {
219 av_log(s, AV_LOG_ERROR, "Version %d not supported.\n",
221 return AVERROR(ENOSYS);
224 GET_V(stream_count, tmp > 0 && tmp <= NUT_MAX_STREAMS);
226 nut->max_distance = ffio_read_varlen(bc);
227 if (nut->max_distance > 65536) {
228 av_log(s, AV_LOG_DEBUG, "max_distance %d\n", nut->max_distance);
229 nut->max_distance = 65536;
232 GET_V(nut->time_base_count, tmp > 0 && tmp < INT_MAX / sizeof(AVRational));
233 nut->time_base = av_malloc(nut->time_base_count * sizeof(AVRational));
235 for (i = 0; i < nut->time_base_count; i++) {
236 GET_V(nut->time_base[i].num, tmp > 0 && tmp < (1ULL << 31));
237 GET_V(nut->time_base[i].den, tmp > 0 && tmp < (1ULL << 31));
238 if (av_gcd(nut->time_base[i].num, nut->time_base[i].den) != 1) {
239 av_log(s, AV_LOG_ERROR, "time base invalid\n");
240 return AVERROR_INVALIDDATA;
247 for (i = 0; i < 256;) {
248 int tmp_flags = ffio_read_varlen(bc);
249 int tmp_fields = ffio_read_varlen(bc);
254 tmp_mul = ffio_read_varlen(bc);
256 tmp_stream = ffio_read_varlen(bc);
258 tmp_size = ffio_read_varlen(bc);
262 tmp_res = ffio_read_varlen(bc);
266 count = ffio_read_varlen(bc);
268 count = tmp_mul - tmp_size;
272 tmp_head_idx = ffio_read_varlen(bc);
274 while (tmp_fields-- > 8)
275 ffio_read_varlen(bc);
277 if (count == 0 || i + count > 256) {
278 av_log(s, AV_LOG_ERROR, "illegal count %d at %d\n", count, i);
279 return AVERROR_INVALIDDATA;
281 if (tmp_stream >= stream_count) {
282 av_log(s, AV_LOG_ERROR, "illegal stream number\n");
283 return AVERROR_INVALIDDATA;
286 for (j = 0; j < count; j++, i++) {
288 nut->frame_code[i].flags = FLAG_INVALID;
292 nut->frame_code[i].flags = tmp_flags;
293 nut->frame_code[i].pts_delta = tmp_pts;
294 nut->frame_code[i].stream_id = tmp_stream;
295 nut->frame_code[i].size_mul = tmp_mul;
296 nut->frame_code[i].size_lsb = tmp_size + j;
297 nut->frame_code[i].reserved_count = tmp_res;
298 nut->frame_code[i].header_idx = tmp_head_idx;
301 assert(nut->frame_code['N'].flags == FLAG_INVALID);
303 if (end > avio_tell(bc) + 4) {
305 GET_V(nut->header_count, tmp < 128U);
307 for (i = 1; i < nut->header_count; i++) {
309 GET_V(nut->header_len[i], tmp > 0 && tmp < 256);
310 rem -= nut->header_len[i];
312 av_log(s, AV_LOG_ERROR, "invalid elision header\n");
313 return AVERROR_INVALIDDATA;
315 hdr = av_malloc(nut->header_len[i]);
317 return AVERROR(ENOMEM);
318 avio_read(bc, hdr, nut->header_len[i]);
319 nut->header[i] = hdr;
321 assert(nut->header_len[0] == 0);
324 // flags had been effectively introduced in version 4
325 if (nut->version > NUT_STABLE_VERSION) {
326 nut->flags = ffio_read_varlen(bc);
329 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
330 av_log(s, AV_LOG_ERROR, "main header checksum mismatch\n");
331 return AVERROR_INVALIDDATA;
334 nut->stream = av_mallocz(sizeof(StreamContext) * stream_count);
335 for (i = 0; i < stream_count; i++)
336 avformat_new_stream(s, NULL);
341 static int decode_stream_header(NUTContext *nut)
343 AVFormatContext *s = nut->avf;
344 AVIOContext *bc = s->pb;
346 int class, stream_id;
350 end = get_packetheader(nut, bc, 1, STREAM_STARTCODE);
351 end += avio_tell(bc);
353 GET_V(stream_id, tmp < s->nb_streams && !nut->stream[tmp].time_base);
354 stc = &nut->stream[stream_id];
355 st = s->streams[stream_id];
357 return AVERROR(ENOMEM);
359 class = ffio_read_varlen(bc);
360 tmp = get_fourcc(bc);
361 st->codec->codec_tag = tmp;
364 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
365 st->codec->codec_id = av_codec_get_id((const AVCodecTag * const []) {
373 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
374 st->codec->codec_id = av_codec_get_id((const AVCodecTag * const []) {
382 st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
383 st->codec->codec_id = ff_codec_get_id(ff_nut_subtitle_tags, tmp);
386 st->codec->codec_type = AVMEDIA_TYPE_DATA;
387 st->codec->codec_id = ff_codec_get_id(ff_nut_data_tags, tmp);
390 av_log(s, AV_LOG_ERROR, "unknown stream class (%d)\n", class);
391 return AVERROR(ENOSYS);
393 if (class < 3 && st->codec->codec_id == AV_CODEC_ID_NONE)
394 av_log(s, AV_LOG_ERROR,
395 "Unknown codec tag '0x%04x' for stream number %d\n",
396 (unsigned int) tmp, stream_id);
398 GET_V(stc->time_base_id, tmp < nut->time_base_count);
399 GET_V(stc->msb_pts_shift, tmp < 16);
400 stc->max_pts_distance = ffio_read_varlen(bc);
401 GET_V(stc->decode_delay, tmp < 1000); // sanity limit, raise this if Moore's law is true
402 st->codec->has_b_frames = stc->decode_delay;
403 ffio_read_varlen(bc); // stream flags
405 GET_V(st->codec->extradata_size, tmp < (1 << 30));
406 if (st->codec->extradata_size) {
407 st->codec->extradata = av_mallocz(st->codec->extradata_size +
408 FF_INPUT_BUFFER_PADDING_SIZE);
409 avio_read(bc, st->codec->extradata, st->codec->extradata_size);
412 if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
413 GET_V(st->codec->width, tmp > 0);
414 GET_V(st->codec->height, tmp > 0);
415 st->sample_aspect_ratio.num = ffio_read_varlen(bc);
416 st->sample_aspect_ratio.den = ffio_read_varlen(bc);
417 if ((!st->sample_aspect_ratio.num) != (!st->sample_aspect_ratio.den)) {
418 av_log(s, AV_LOG_ERROR, "invalid aspect ratio %d/%d\n",
419 st->sample_aspect_ratio.num, st->sample_aspect_ratio.den);
420 return AVERROR_INVALIDDATA;
422 ffio_read_varlen(bc); /* csp type */
423 } else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
424 GET_V(st->codec->sample_rate, tmp > 0);
425 ffio_read_varlen(bc); // samplerate_den
426 GET_V(st->codec->channels, tmp > 0);
428 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
429 av_log(s, AV_LOG_ERROR,
430 "stream header %d checksum mismatch\n", stream_id);
431 return AVERROR_INVALIDDATA;
433 stc->time_base = &nut->time_base[stc->time_base_id];
434 avpriv_set_pts_info(s->streams[stream_id], 63, stc->time_base->num,
435 stc->time_base->den);
439 static void set_disposition_bits(AVFormatContext *avf, char *value,
444 for (i = 0; ff_nut_dispositions[i].flag; ++i)
445 if (!strcmp(ff_nut_dispositions[i].str, value))
446 flag = ff_nut_dispositions[i].flag;
448 av_log(avf, AV_LOG_INFO, "unknown disposition type '%s'\n", value);
449 for (i = 0; i < avf->nb_streams; ++i)
450 if (stream_id == i || stream_id == -1)
451 avf->streams[i]->disposition |= flag;
454 static int decode_info_header(NUTContext *nut)
456 AVFormatContext *s = nut->avf;
457 AVIOContext *bc = s->pb;
458 uint64_t tmp, chapter_start, chapter_len;
459 unsigned int stream_id_plus1, count;
462 char name[256], str_value[1024], type_str[256];
465 AVChapter *chapter = NULL;
467 AVDictionary **metadata = NULL;
468 int metadata_flag = 0;
470 end = get_packetheader(nut, bc, 1, INFO_STARTCODE);
471 end += avio_tell(bc);
473 GET_V(stream_id_plus1, tmp <= s->nb_streams);
474 chapter_id = get_s(bc);
475 chapter_start = ffio_read_varlen(bc);
476 chapter_len = ffio_read_varlen(bc);
477 count = ffio_read_varlen(bc);
479 if (chapter_id && !stream_id_plus1) {
480 int64_t start = chapter_start / nut->time_base_count;
481 chapter = avpriv_new_chapter(s, chapter_id,
482 nut->time_base[chapter_start %
483 nut->time_base_count],
484 start, start + chapter_len, NULL);
485 metadata = &chapter->metadata;
486 } else if (stream_id_plus1) {
487 st = s->streams[stream_id_plus1 - 1];
488 metadata = &st->metadata;
489 event_flags = &st->event_flags;
490 metadata_flag = AVSTREAM_EVENT_FLAG_METADATA_UPDATED;
492 metadata = &s->metadata;
493 event_flags = &s->event_flags;
494 metadata_flag = AVFMT_EVENT_FLAG_METADATA_UPDATED;
497 for (i = 0; i < count; i++) {
498 get_str(bc, name, sizeof(name));
502 get_str(bc, str_value, sizeof(str_value));
503 } else if (value == -2) {
504 get_str(bc, type_str, sizeof(type_str));
506 get_str(bc, str_value, sizeof(str_value));
507 } else if (value == -3) {
510 } else if (value == -4) {
512 value = ffio_read_varlen(bc);
513 } else if (value < -4) {
520 if (stream_id_plus1 > s->nb_streams) {
521 av_log(s, AV_LOG_ERROR, "invalid stream id for info packet\n");
525 if (!strcmp(type, "UTF-8")) {
526 if (chapter_id == 0 && !strcmp(name, "Disposition")) {
527 set_disposition_bits(s, str_value, stream_id_plus1 - 1);
530 if (metadata && av_strcasecmp(name, "Uses") &&
531 av_strcasecmp(name, "Depends") && av_strcasecmp(name, "Replaces")) {
532 *event_flags |= metadata_flag;
533 av_dict_set(metadata, name, str_value, 0);
538 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
539 av_log(s, AV_LOG_ERROR, "info header checksum mismatch\n");
540 return AVERROR_INVALIDDATA;
545 static int decode_syncpoint(NUTContext *nut, int64_t *ts, int64_t *back_ptr)
547 AVFormatContext *s = nut->avf;
548 AVIOContext *bc = s->pb;
552 nut->last_syncpoint_pos = avio_tell(bc) - 8;
554 end = get_packetheader(nut, bc, 1, SYNCPOINT_STARTCODE);
555 end += avio_tell(bc);
557 tmp = ffio_read_varlen(bc);
558 *back_ptr = nut->last_syncpoint_pos - 16 * ffio_read_varlen(bc);
562 ff_nut_reset_ts(nut, nut->time_base[tmp % nut->time_base_count],
563 tmp / nut->time_base_count);
565 if (nut->flags & NUT_BROADCAST) {
566 tmp = ffio_read_varlen(bc);
567 av_log(s, AV_LOG_VERBOSE, "Syncpoint wallclock %"PRId64"\n",
568 av_rescale_q(tmp / nut->time_base_count,
569 nut->time_base[tmp % nut->time_base_count],
573 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
574 av_log(s, AV_LOG_ERROR, "sync point checksum mismatch\n");
575 return AVERROR_INVALIDDATA;
578 *ts = tmp / s->nb_streams *
579 av_q2d(nut->time_base[tmp % s->nb_streams]) * AV_TIME_BASE;
581 if ((ret = ff_nut_add_sp(nut, nut->last_syncpoint_pos, *back_ptr, *ts)) < 0)
587 static int find_and_decode_index(NUTContext *nut)
589 AVFormatContext *s = nut->avf;
590 AVIOContext *bc = s->pb;
592 int i, j, syncpoint_count;
593 int64_t filesize = avio_size(bc);
595 int8_t *has_keyframe;
596 int ret = AVERROR_INVALIDDATA;
598 avio_seek(bc, filesize - 12, SEEK_SET);
599 avio_seek(bc, filesize - avio_rb64(bc), SEEK_SET);
600 if (avio_rb64(bc) != INDEX_STARTCODE) {
601 av_log(s, AV_LOG_ERROR, "no index at the end\n");
605 end = get_packetheader(nut, bc, 1, INDEX_STARTCODE);
606 end += avio_tell(bc);
608 ffio_read_varlen(bc); // max_pts
609 GET_V(syncpoint_count, tmp < INT_MAX / 8 && tmp > 0);
610 syncpoints = av_malloc(sizeof(int64_t) * syncpoint_count);
611 has_keyframe = av_malloc(sizeof(int8_t) * (syncpoint_count + 1));
612 for (i = 0; i < syncpoint_count; i++) {
613 syncpoints[i] = ffio_read_varlen(bc);
614 if (syncpoints[i] <= 0)
617 syncpoints[i] += syncpoints[i - 1];
620 for (i = 0; i < s->nb_streams; i++) {
621 int64_t last_pts = -1;
622 for (j = 0; j < syncpoint_count;) {
623 uint64_t x = ffio_read_varlen(bc);
630 if (n + x >= syncpoint_count + 1) {
631 av_log(s, AV_LOG_ERROR, "index overflow A\n");
635 has_keyframe[n++] = flag;
636 has_keyframe[n++] = !flag;
639 if (n >= syncpoint_count + 1) {
640 av_log(s, AV_LOG_ERROR, "index overflow B\n");
643 has_keyframe[n++] = x & 1;
647 if (has_keyframe[0]) {
648 av_log(s, AV_LOG_ERROR, "keyframe before first syncpoint in index\n");
651 assert(n <= syncpoint_count + 1);
652 for (; j < n && j < syncpoint_count; j++) {
653 if (has_keyframe[j]) {
654 uint64_t B, A = ffio_read_varlen(bc);
656 A = ffio_read_varlen(bc);
657 B = ffio_read_varlen(bc);
658 // eor_pts[j][i] = last_pts + A + B
661 av_add_index_entry(s->streams[i], 16 * syncpoints[j - 1],
662 last_pts + A, 0, 0, AVINDEX_KEYFRAME);
669 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
670 av_log(s, AV_LOG_ERROR, "index checksum mismatch\n");
677 av_free(has_keyframe);
681 static int nut_read_header(AVFormatContext *s)
683 NUTContext *nut = s->priv_data;
684 AVIOContext *bc = s->pb;
686 int initialized_stream_count;
693 pos = find_startcode(bc, MAIN_STARTCODE, pos) + 1;
695 av_log(s, AV_LOG_ERROR, "No main startcode found.\n");
696 return AVERROR_INVALIDDATA;
698 } while (decode_main_header(nut) < 0);
702 for (initialized_stream_count = 0; initialized_stream_count < s->nb_streams;) {
703 pos = find_startcode(bc, STREAM_STARTCODE, pos) + 1;
705 av_log(s, AV_LOG_ERROR, "Not all stream headers found.\n");
706 return AVERROR_INVALIDDATA;
708 if (decode_stream_header(nut) >= 0)
709 initialized_stream_count++;
715 uint64_t startcode = find_any_startcode(bc, pos);
718 if (startcode == 0) {
719 av_log(s, AV_LOG_ERROR, "EOF before video frames\n");
720 return AVERROR_INVALIDDATA;
721 } else if (startcode == SYNCPOINT_STARTCODE) {
722 nut->next_startcode = startcode;
724 } else if (startcode != INFO_STARTCODE) {
728 decode_info_header(nut);
731 s->data_offset = pos - 8;
734 int64_t orig_pos = avio_tell(bc);
735 find_and_decode_index(nut);
736 avio_seek(bc, orig_pos, SEEK_SET);
738 assert(nut->next_startcode == SYNCPOINT_STARTCODE);
740 ff_metadata_conv_ctx(s, NULL, ff_nut_metadata_conv);
745 static int decode_frame_header(NUTContext *nut, int64_t *pts, int *stream_id,
746 uint8_t *header_idx, int frame_code)
748 AVFormatContext *s = nut->avf;
749 AVIOContext *bc = s->pb;
751 int size, flags, size_mul, pts_delta, i, reserved_count;
754 if (!(nut->flags & NUT_PIPE) &&
755 avio_tell(bc) > nut->last_syncpoint_pos + nut->max_distance) {
756 av_log(s, AV_LOG_ERROR,
757 "Last frame must have been damaged %"PRId64" > %"PRId64" + %d\n",
758 avio_tell(bc), nut->last_syncpoint_pos, nut->max_distance);
759 return AVERROR_INVALIDDATA;
762 flags = nut->frame_code[frame_code].flags;
763 size_mul = nut->frame_code[frame_code].size_mul;
764 size = nut->frame_code[frame_code].size_lsb;
765 *stream_id = nut->frame_code[frame_code].stream_id;
766 pts_delta = nut->frame_code[frame_code].pts_delta;
767 reserved_count = nut->frame_code[frame_code].reserved_count;
768 *header_idx = nut->frame_code[frame_code].header_idx;
770 if (flags & FLAG_INVALID)
771 return AVERROR_INVALIDDATA;
772 if (flags & FLAG_CODED)
773 flags ^= ffio_read_varlen(bc);
774 if (flags & FLAG_STREAM_ID) {
775 GET_V(*stream_id, tmp < s->nb_streams);
777 stc = &nut->stream[*stream_id];
778 if (flags & FLAG_CODED_PTS) {
779 int coded_pts = ffio_read_varlen(bc);
780 // FIXME check last_pts validity?
781 if (coded_pts < (1 << stc->msb_pts_shift)) {
782 *pts = ff_lsb2full(stc, coded_pts);
784 *pts = coded_pts - (1 << stc->msb_pts_shift);
786 *pts = stc->last_pts + pts_delta;
787 if (flags & FLAG_SIZE_MSB)
788 size += size_mul * ffio_read_varlen(bc);
789 if (flags & FLAG_MATCH_TIME)
791 if (flags & FLAG_HEADER_IDX)
792 *header_idx = ffio_read_varlen(bc);
793 if (flags & FLAG_RESERVED)
794 reserved_count = ffio_read_varlen(bc);
795 for (i = 0; i < reserved_count; i++)
796 ffio_read_varlen(bc);
798 if (*header_idx >= (unsigned)nut->header_count) {
799 av_log(s, AV_LOG_ERROR, "header_idx invalid\n");
800 return AVERROR_INVALIDDATA;
804 size -= nut->header_len[*header_idx];
806 if (flags & FLAG_CHECKSUM) {
807 avio_rb32(bc); // FIXME check this
808 } else if (!(nut->flags & NUT_PIPE) &&
809 size > 2 * nut->max_distance ||
810 FFABS(stc->last_pts - *pts) > stc->max_pts_distance) {
811 av_log(s, AV_LOG_ERROR, "frame size > 2max_distance and no checksum\n");
812 return AVERROR_INVALIDDATA;
815 stc->last_pts = *pts;
816 stc->last_flags = flags;
821 static int decode_frame(NUTContext *nut, AVPacket *pkt, int frame_code)
823 AVFormatContext *s = nut->avf;
824 AVIOContext *bc = s->pb;
825 int size, stream_id, discard;
826 int64_t pts, last_IP_pts;
830 size = decode_frame_header(nut, &pts, &stream_id, &header_idx, frame_code);
834 stc = &nut->stream[stream_id];
836 if (stc->last_flags & FLAG_KEY)
837 stc->skip_until_key_frame = 0;
839 discard = s->streams[stream_id]->discard;
840 last_IP_pts = s->streams[stream_id]->last_IP_pts;
841 if ((discard >= AVDISCARD_NONKEY && !(stc->last_flags & FLAG_KEY)) ||
842 (discard >= AVDISCARD_BIDIR && last_IP_pts != AV_NOPTS_VALUE &&
843 last_IP_pts > pts) ||
844 discard >= AVDISCARD_ALL ||
845 stc->skip_until_key_frame) {
850 av_new_packet(pkt, size + nut->header_len[header_idx]);
851 memcpy(pkt->data, nut->header[header_idx], nut->header_len[header_idx]);
852 pkt->pos = avio_tell(bc); // FIXME
853 avio_read(bc, pkt->data + nut->header_len[header_idx], size);
855 pkt->stream_index = stream_id;
856 if (stc->last_flags & FLAG_KEY)
857 pkt->flags |= AV_PKT_FLAG_KEY;
863 static int nut_read_packet(AVFormatContext *s, AVPacket *pkt)
865 NUTContext *nut = s->priv_data;
866 AVIOContext *bc = s->pb;
867 int i, frame_code = 0, ret, skip;
868 int64_t ts, back_ptr;
871 int64_t pos = avio_tell(bc);
872 uint64_t tmp = nut->next_startcode;
873 nut->next_startcode = 0;
878 frame_code = avio_r8(bc);
881 if (frame_code == 'N') {
883 for (i = 1; i < 8; i++)
884 tmp = (tmp << 8) + avio_r8(bc);
889 case STREAM_STARTCODE:
890 case INDEX_STARTCODE:
891 skip = get_packetheader(nut, bc, 0, tmp);
895 if (decode_info_header(nut) < 0)
898 case SYNCPOINT_STARTCODE:
899 if (decode_syncpoint(nut, &ts, &back_ptr) < 0)
901 frame_code = avio_r8(bc);
903 ret = decode_frame(nut, pkt, frame_code);
906 else if (ret == 1) // OK but discard packet
910 av_log(s, AV_LOG_DEBUG, "syncing from %"PRId64"\n", pos);
911 tmp = find_any_startcode(bc, nut->last_syncpoint_pos + 1);
913 return AVERROR_INVALIDDATA;
914 av_log(s, AV_LOG_DEBUG, "sync\n");
915 nut->next_startcode = tmp;
920 static int64_t nut_read_timestamp(AVFormatContext *s, int stream_index,
921 int64_t *pos_arg, int64_t pos_limit)
923 NUTContext *nut = s->priv_data;
924 AVIOContext *bc = s->pb;
925 int64_t pos, pts, back_ptr;
926 av_log(s, AV_LOG_DEBUG, "read_timestamp(X,%d,%"PRId64",%"PRId64")\n",
927 stream_index, *pos_arg, pos_limit);
931 pos = find_startcode(bc, SYNCPOINT_STARTCODE, pos) + 1;
933 assert(nut->next_startcode == 0);
934 av_log(s, AV_LOG_ERROR, "read_timestamp failed.\n");
935 return AV_NOPTS_VALUE;
937 } while (decode_syncpoint(nut, &pts, &back_ptr) < 0);
939 assert(nut->last_syncpoint_pos == *pos_arg);
941 av_log(s, AV_LOG_DEBUG, "return %"PRId64" %"PRId64"\n", pts, back_ptr);
942 if (stream_index == -1)
944 else if (stream_index == -2)
947 return AV_NOPTS_VALUE;
950 static int read_seek(AVFormatContext *s, int stream_index,
951 int64_t pts, int flags)
953 NUTContext *nut = s->priv_data;
954 AVStream *st = s->streams[stream_index];
955 Syncpoint dummy = { .ts = pts * av_q2d(st->time_base) * AV_TIME_BASE };
956 Syncpoint nopts_sp = { .ts = AV_NOPTS_VALUE, .back_ptr = AV_NOPTS_VALUE };
957 Syncpoint *sp, *next_node[2] = { &nopts_sp, &nopts_sp };
958 int64_t pos, pos2, ts;
961 if (nut->flags & NUT_PIPE) {
962 return AVERROR(ENOSYS);
965 if (st->index_entries) {
966 int index = av_index_search_timestamp(st, pts, flags);
970 pos2 = st->index_entries[index].pos;
971 ts = st->index_entries[index].timestamp;
973 av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pts_cmp,
974 (void **) next_node);
975 av_log(s, AV_LOG_DEBUG, "%"PRIu64"-%"PRIu64" %"PRId64"-%"PRId64"\n",
976 next_node[0]->pos, next_node[1]->pos, next_node[0]->ts,
978 pos = ff_gen_search(s, -1, dummy.ts, next_node[0]->pos,
979 next_node[1]->pos, next_node[1]->pos,
980 next_node[0]->ts, next_node[1]->ts,
981 AVSEEK_FLAG_BACKWARD, &ts, nut_read_timestamp);
983 if (!(flags & AVSEEK_FLAG_BACKWARD)) {
984 dummy.pos = pos + 16;
985 next_node[1] = &nopts_sp;
986 av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp,
987 (void **) next_node);
988 pos2 = ff_gen_search(s, -2, dummy.pos, next_node[0]->pos,
989 next_node[1]->pos, next_node[1]->pos,
990 next_node[0]->back_ptr, next_node[1]->back_ptr,
991 flags, &ts, nut_read_timestamp);
994 // FIXME dir but I think it does not matter
997 sp = av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp,
1001 pos2 = sp->back_ptr - 15;
1003 av_log(NULL, AV_LOG_DEBUG, "SEEKTO: %"PRId64"\n", pos2);
1004 pos = find_startcode(s->pb, SYNCPOINT_STARTCODE, pos2);
1005 avio_seek(s->pb, pos, SEEK_SET);
1006 av_log(NULL, AV_LOG_DEBUG, "SP: %"PRId64"\n", pos);
1007 if (pos2 > pos || pos2 + 15 < pos)
1008 av_log(NULL, AV_LOG_ERROR, "no syncpoint at backptr pos\n");
1009 for (i = 0; i < s->nb_streams; i++)
1010 nut->stream[i].skip_until_key_frame = 1;
1015 static int nut_read_close(AVFormatContext *s)
1017 NUTContext *nut = s->priv_data;
1020 av_freep(&nut->time_base);
1021 av_freep(&nut->stream);
1022 ff_nut_free_sp(nut);
1023 for (i = 1; i < nut->header_count; i++)
1024 av_freep(&nut->header[i]);
1029 AVInputFormat ff_nut_demuxer = {
1031 .long_name = NULL_IF_CONFIG_SMALL("NUT"),
1032 .priv_data_size = sizeof(NUTContext),
1033 .read_probe = nut_probe,
1034 .read_header = nut_read_header,
1035 .read_packet = nut_read_packet,
1036 .read_close = nut_read_close,
1037 .read_seek = read_seek,
1038 .extensions = "nut",
1039 .codec_tag = ff_nut_codec_tags,