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); \
204 static int skip_reserved(AVIOContext *bc, int64_t pos)
206 pos -= avio_tell(bc);
208 avio_seek(bc, pos, SEEK_CUR);
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 GET_V(tmp, tmp >= 2 && tmp <= 3);
230 GET_V(stream_count, tmp > 0 && tmp <= NUT_MAX_STREAMS);
232 nut->max_distance = ffio_read_varlen(bc);
233 if (nut->max_distance > 65536) {
234 av_log(s, AV_LOG_DEBUG, "max_distance %d\n", nut->max_distance);
235 nut->max_distance = 65536;
238 GET_V(nut->time_base_count, tmp > 0 && tmp < INT_MAX / sizeof(AVRational));
239 nut->time_base = av_malloc(nut->time_base_count * sizeof(AVRational));
241 for (i = 0; i < nut->time_base_count; i++) {
242 GET_V(nut->time_base[i].num, tmp > 0 && tmp < (1ULL << 31));
243 GET_V(nut->time_base[i].den, tmp > 0 && tmp < (1ULL << 31));
244 if (av_gcd(nut->time_base[i].num, nut->time_base[i].den) != 1) {
245 av_log(s, AV_LOG_ERROR, "time base invalid\n");
246 return AVERROR_INVALIDDATA;
253 for (i = 0; i < 256;) {
254 int tmp_flags = ffio_read_varlen(bc);
255 int tmp_fields = ffio_read_varlen(bc);
260 tmp_mul = ffio_read_varlen(bc);
262 tmp_stream = ffio_read_varlen(bc);
264 tmp_size = ffio_read_varlen(bc);
268 tmp_res = ffio_read_varlen(bc);
272 count = ffio_read_varlen(bc);
274 count = tmp_mul - tmp_size;
278 tmp_head_idx = ffio_read_varlen(bc);
280 while (tmp_fields-- > 8)
281 ffio_read_varlen(bc);
283 if (count == 0 || i + count > 256) {
284 av_log(s, AV_LOG_ERROR, "illegal count %d at %d\n", count, i);
285 return AVERROR_INVALIDDATA;
287 if (tmp_stream >= stream_count) {
288 av_log(s, AV_LOG_ERROR, "illegal stream number\n");
289 return AVERROR_INVALIDDATA;
292 for (j = 0; j < count; j++, i++) {
294 nut->frame_code[i].flags = FLAG_INVALID;
298 nut->frame_code[i].flags = tmp_flags;
299 nut->frame_code[i].pts_delta = tmp_pts;
300 nut->frame_code[i].stream_id = tmp_stream;
301 nut->frame_code[i].size_mul = tmp_mul;
302 nut->frame_code[i].size_lsb = tmp_size + j;
303 nut->frame_code[i].reserved_count = tmp_res;
304 nut->frame_code[i].header_idx = tmp_head_idx;
307 av_assert0(nut->frame_code['N'].flags == FLAG_INVALID);
309 if (end > avio_tell(bc) + 4) {
311 GET_V(nut->header_count, tmp < 128U);
313 for (i = 1; i < nut->header_count; i++) {
315 GET_V(nut->header_len[i], tmp > 0 && tmp < 256);
316 rem -= nut->header_len[i];
318 av_log(s, AV_LOG_ERROR, "invalid elision header\n");
319 return AVERROR_INVALIDDATA;
321 hdr = av_malloc(nut->header_len[i]);
323 return AVERROR(ENOMEM);
324 avio_read(bc, hdr, nut->header_len[i]);
325 nut->header[i] = hdr;
327 av_assert0(nut->header_len[0] == 0);
330 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
331 av_log(s, AV_LOG_ERROR, "main header checksum mismatch\n");
332 return AVERROR_INVALIDDATA;
335 nut->stream = av_mallocz(sizeof(StreamContext) * stream_count);
336 for (i = 0; i < stream_count; i++)
337 avformat_new_stream(s, NULL);
342 static int decode_stream_header(NUTContext *nut)
344 AVFormatContext *s = nut->avf;
345 AVIOContext *bc = s->pb;
347 int class, stream_id;
351 end = get_packetheader(nut, bc, 1, STREAM_STARTCODE);
352 end += avio_tell(bc);
354 GET_V(stream_id, tmp < s->nb_streams && !nut->stream[tmp].time_base);
355 stc = &nut->stream[stream_id];
356 st = s->streams[stream_id];
358 return AVERROR(ENOMEM);
360 class = ffio_read_varlen(bc);
361 tmp = get_fourcc(bc);
362 st->codec->codec_tag = tmp;
365 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
366 st->codec->codec_id = av_codec_get_id((const AVCodecTag * const []) {
374 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
375 st->codec->codec_id = av_codec_get_id((const AVCodecTag * const []) {
383 st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
384 st->codec->codec_id = ff_codec_get_id(ff_nut_subtitle_tags, tmp);
387 st->codec->codec_type = AVMEDIA_TYPE_DATA;
388 st->codec->codec_id = ff_codec_get_id(ff_nut_data_tags, tmp);
391 av_log(s, AV_LOG_ERROR, "unknown stream class (%d)\n", class);
394 if (class < 3 && st->codec->codec_id == AV_CODEC_ID_NONE)
395 av_log(s, AV_LOG_ERROR,
396 "Unknown codec tag '0x%04x' for stream number %d\n",
397 (unsigned int) tmp, stream_id);
399 GET_V(stc->time_base_id, tmp < nut->time_base_count);
400 GET_V(stc->msb_pts_shift, tmp < 16);
401 stc->max_pts_distance = ffio_read_varlen(bc);
402 GET_V(stc->decode_delay, tmp < 1000); // sanity limit, raise this if Moore's law is true
403 st->codec->has_b_frames = stc->decode_delay;
404 ffio_read_varlen(bc); // stream flags
406 GET_V(st->codec->extradata_size, tmp < (1 << 30));
407 if (st->codec->extradata_size) {
408 st->codec->extradata = av_mallocz(st->codec->extradata_size +
409 FF_INPUT_BUFFER_PADDING_SIZE);
410 avio_read(bc, st->codec->extradata, st->codec->extradata_size);
413 if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
414 GET_V(st->codec->width, tmp > 0);
415 GET_V(st->codec->height, tmp > 0);
416 st->sample_aspect_ratio.num = ffio_read_varlen(bc);
417 st->sample_aspect_ratio.den = ffio_read_varlen(bc);
418 if ((!st->sample_aspect_ratio.num) != (!st->sample_aspect_ratio.den)) {
419 av_log(s, AV_LOG_ERROR, "invalid aspect ratio %d/%d\n",
420 st->sample_aspect_ratio.num, st->sample_aspect_ratio.den);
423 ffio_read_varlen(bc); /* csp type */
424 } else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
425 GET_V(st->codec->sample_rate, tmp > 0);
426 ffio_read_varlen(bc); // samplerate_den
427 GET_V(st->codec->channels, tmp > 0);
429 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
430 av_log(s, AV_LOG_ERROR,
431 "stream header %d checksum mismatch\n", stream_id);
434 stc->time_base = &nut->time_base[stc->time_base_id];
435 avpriv_set_pts_info(s->streams[stream_id], 63, stc->time_base->num,
436 stc->time_base->den);
440 static void set_disposition_bits(AVFormatContext *avf, char *value,
445 for (i = 0; ff_nut_dispositions[i].flag; ++i)
446 if (!strcmp(ff_nut_dispositions[i].str, value))
447 flag = ff_nut_dispositions[i].flag;
449 av_log(avf, AV_LOG_INFO, "unknown disposition type '%s'\n", value);
450 for (i = 0; i < avf->nb_streams; ++i)
451 if (stream_id == i || stream_id == -1)
452 avf->streams[i]->disposition |= flag;
455 static int decode_info_header(NUTContext *nut)
457 AVFormatContext *s = nut->avf;
458 AVIOContext *bc = s->pb;
459 uint64_t tmp, chapter_start, chapter_len;
460 unsigned int stream_id_plus1, count;
463 char name[256], str_value[1024], type_str[256];
465 AVChapter *chapter = NULL;
467 AVDictionary **metadata = NULL;
469 end = get_packetheader(nut, bc, 1, INFO_STARTCODE);
470 end += avio_tell(bc);
472 GET_V(stream_id_plus1, tmp <= s->nb_streams);
473 chapter_id = get_s(bc);
474 chapter_start = ffio_read_varlen(bc);
475 chapter_len = ffio_read_varlen(bc);
476 count = ffio_read_varlen(bc);
478 if (chapter_id && !stream_id_plus1) {
479 int64_t start = chapter_start / nut->time_base_count;
480 chapter = avpriv_new_chapter(s, chapter_id,
481 nut->time_base[chapter_start %
482 nut->time_base_count],
483 start, start + chapter_len, NULL);
484 metadata = &chapter->metadata;
485 } else if (stream_id_plus1) {
486 st = s->streams[stream_id_plus1 - 1];
487 metadata = &st->metadata;
489 metadata = &s->metadata;
491 for (i = 0; i < count; i++) {
492 get_str(bc, name, sizeof(name));
496 get_str(bc, str_value, sizeof(str_value));
497 } else if (value == -2) {
498 get_str(bc, type_str, sizeof(type_str));
500 get_str(bc, str_value, sizeof(str_value));
501 } else if (value == -3) {
504 } else if (value == -4) {
506 value = ffio_read_varlen(bc);
507 } else if (value < -4) {
514 if (stream_id_plus1 > s->nb_streams) {
515 av_log(s, AV_LOG_ERROR, "invalid stream id for info packet\n");
519 if (!strcmp(type, "UTF-8")) {
520 if (chapter_id == 0 && !strcmp(name, "Disposition")) {
521 set_disposition_bits(s, str_value, stream_id_plus1 - 1);
525 if (stream_id_plus1 && !strcmp(name, "r_frame_rate")) {
526 sscanf(str_value, "%d/%d", &st->r_frame_rate.num, &st->r_frame_rate.den);
527 if (st->r_frame_rate.num >= 1000LL*st->r_frame_rate.den)
528 st->r_frame_rate.num = st->r_frame_rate.den = 0;
532 if (metadata && av_strcasecmp(name, "Uses") &&
533 av_strcasecmp(name, "Depends") && av_strcasecmp(name, "Replaces"))
534 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");
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);
560 return AVERROR_INVALIDDATA;
562 ff_nut_reset_ts(nut, nut->time_base[tmp % nut->time_base_count],
563 tmp / nut->time_base_count);
565 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
566 av_log(s, AV_LOG_ERROR, "sync point checksum mismatch\n");
567 return AVERROR_INVALIDDATA;
570 *ts = tmp / nut->time_base_count *
571 av_q2d(nut->time_base[tmp % nut->time_base_count]) * AV_TIME_BASE;
572 ff_nut_add_sp(nut, nut->last_syncpoint_pos, *back_ptr, *ts);
577 //FIXME calculate exactly, this is just a good approximation.
578 static int64_t find_duration(NUTContext *nut, int64_t filesize)
580 AVFormatContext *s = nut->avf;
581 int64_t duration = 0;
583 int64_t pos = FFMAX(0, filesize - 2*nut->max_distance);
585 int64_t ts = nut_read_timestamp(s, -1, &pos, INT64_MAX);
588 duration = FFMAX(duration, ts);
592 s->duration_estimation_method = AVFMT_DURATION_FROM_PTS;
596 static int find_and_decode_index(NUTContext *nut)
598 AVFormatContext *s = nut->avf;
599 AVIOContext *bc = s->pb;
601 int i, j, syncpoint_count;
602 int64_t filesize = avio_size(bc);
605 int8_t *has_keyframe;
611 avio_seek(bc, filesize - 12, SEEK_SET);
612 avio_seek(bc, filesize - avio_rb64(bc), SEEK_SET);
613 if (avio_rb64(bc) != INDEX_STARTCODE) {
614 av_log(s, AV_LOG_ERROR, "no index at the end\n");
617 s->duration = find_duration(nut, filesize);
621 end = get_packetheader(nut, bc, 1, INDEX_STARTCODE);
622 end += avio_tell(bc);
624 max_pts = ffio_read_varlen(bc);
625 s->duration = av_rescale_q(max_pts / nut->time_base_count,
626 nut->time_base[max_pts % nut->time_base_count],
628 s->duration_estimation_method = AVFMT_DURATION_FROM_PTS;
630 GET_V(syncpoint_count, tmp < INT_MAX / 8 && tmp > 0);
631 syncpoints = av_malloc(sizeof(int64_t) * syncpoint_count);
632 has_keyframe = av_malloc(sizeof(int8_t) * (syncpoint_count + 1));
633 for (i = 0; i < syncpoint_count; i++) {
634 syncpoints[i] = ffio_read_varlen(bc);
635 if (syncpoints[i] <= 0)
638 syncpoints[i] += syncpoints[i - 1];
641 for (i = 0; i < s->nb_streams; i++) {
642 int64_t last_pts = -1;
643 for (j = 0; j < syncpoint_count;) {
644 uint64_t x = ffio_read_varlen(bc);
651 if (n + x >= syncpoint_count + 1) {
652 av_log(s, AV_LOG_ERROR, "index overflow A %d + %"PRIu64" >= %d\n", n, x, syncpoint_count + 1);
656 has_keyframe[n++] = flag;
657 has_keyframe[n++] = !flag;
660 if (n >= syncpoint_count + 1) {
661 av_log(s, AV_LOG_ERROR, "index overflow B\n");
664 has_keyframe[n++] = x & 1;
668 if (has_keyframe[0]) {
669 av_log(s, AV_LOG_ERROR, "keyframe before first syncpoint in index\n");
672 av_assert0(n <= syncpoint_count + 1);
673 for (; j < n && j < syncpoint_count; j++) {
674 if (has_keyframe[j]) {
675 uint64_t B, A = ffio_read_varlen(bc);
677 A = ffio_read_varlen(bc);
678 B = ffio_read_varlen(bc);
679 // eor_pts[j][i] = last_pts + A + B
682 av_add_index_entry(s->streams[i], 16 * syncpoints[j - 1],
683 last_pts + A, 0, 0, AVINDEX_KEYFRAME);
690 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
691 av_log(s, AV_LOG_ERROR, "index checksum mismatch\n");
698 av_free(has_keyframe);
702 static int nut_read_header(AVFormatContext *s)
704 NUTContext *nut = s->priv_data;
705 AVIOContext *bc = s->pb;
707 int initialized_stream_count;
714 pos = find_startcode(bc, MAIN_STARTCODE, pos) + 1;
716 av_log(s, AV_LOG_ERROR, "No main startcode found.\n");
717 return AVERROR_INVALIDDATA;
719 } while (decode_main_header(nut) < 0);
723 for (initialized_stream_count = 0; initialized_stream_count < s->nb_streams;) {
724 pos = find_startcode(bc, STREAM_STARTCODE, pos) + 1;
726 av_log(s, AV_LOG_ERROR, "Not all stream headers found.\n");
727 return AVERROR_INVALIDDATA;
729 if (decode_stream_header(nut) >= 0)
730 initialized_stream_count++;
736 uint64_t startcode = find_any_startcode(bc, pos);
739 if (startcode == 0) {
740 av_log(s, AV_LOG_ERROR, "EOF before video frames\n");
741 return AVERROR_INVALIDDATA;
742 } else if (startcode == SYNCPOINT_STARTCODE) {
743 nut->next_startcode = startcode;
745 } else if (startcode != INFO_STARTCODE) {
749 decode_info_header(nut);
752 s->data_offset = pos - 8;
755 int64_t orig_pos = avio_tell(bc);
756 find_and_decode_index(nut);
757 avio_seek(bc, orig_pos, SEEK_SET);
759 av_assert0(nut->next_startcode == SYNCPOINT_STARTCODE);
761 ff_metadata_conv_ctx(s, NULL, ff_nut_metadata_conv);
766 static int decode_frame_header(NUTContext *nut, int64_t *pts, int *stream_id,
767 uint8_t *header_idx, int frame_code)
769 AVFormatContext *s = nut->avf;
770 AVIOContext *bc = s->pb;
772 int size, flags, size_mul, pts_delta, i, reserved_count;
775 if (avio_tell(bc) > nut->last_syncpoint_pos + nut->max_distance) {
776 av_log(s, AV_LOG_ERROR,
777 "Last frame must have been damaged %"PRId64" > %"PRId64" + %d\n",
778 avio_tell(bc), nut->last_syncpoint_pos, nut->max_distance);
779 return AVERROR_INVALIDDATA;
782 flags = nut->frame_code[frame_code].flags;
783 size_mul = nut->frame_code[frame_code].size_mul;
784 size = nut->frame_code[frame_code].size_lsb;
785 *stream_id = nut->frame_code[frame_code].stream_id;
786 pts_delta = nut->frame_code[frame_code].pts_delta;
787 reserved_count = nut->frame_code[frame_code].reserved_count;
788 *header_idx = nut->frame_code[frame_code].header_idx;
790 if (flags & FLAG_INVALID)
791 return AVERROR_INVALIDDATA;
792 if (flags & FLAG_CODED)
793 flags ^= ffio_read_varlen(bc);
794 if (flags & FLAG_STREAM_ID) {
795 GET_V(*stream_id, tmp < s->nb_streams);
797 stc = &nut->stream[*stream_id];
798 if (flags & FLAG_CODED_PTS) {
799 int coded_pts = ffio_read_varlen(bc);
800 // FIXME check last_pts validity?
801 if (coded_pts < (1 << stc->msb_pts_shift)) {
802 *pts = ff_lsb2full(stc, coded_pts);
804 *pts = coded_pts - (1LL << stc->msb_pts_shift);
806 *pts = stc->last_pts + pts_delta;
807 if (flags & FLAG_SIZE_MSB)
808 size += size_mul * ffio_read_varlen(bc);
809 if (flags & FLAG_MATCH_TIME)
811 if (flags & FLAG_HEADER_IDX)
812 *header_idx = ffio_read_varlen(bc);
813 if (flags & FLAG_RESERVED)
814 reserved_count = ffio_read_varlen(bc);
815 for (i = 0; i < reserved_count; i++)
816 ffio_read_varlen(bc);
818 if (*header_idx >= (unsigned)nut->header_count) {
819 av_log(s, AV_LOG_ERROR, "header_idx invalid\n");
820 return AVERROR_INVALIDDATA;
824 size -= nut->header_len[*header_idx];
826 if (flags & FLAG_CHECKSUM) {
827 avio_rb32(bc); // FIXME check this
828 } else if (size > 2 * nut->max_distance || FFABS(stc->last_pts - *pts) >
829 stc->max_pts_distance) {
830 av_log(s, AV_LOG_ERROR, "frame size > 2max_distance and no checksum\n");
831 return AVERROR_INVALIDDATA;
834 stc->last_pts = *pts;
835 stc->last_flags = flags;
840 static int decode_frame(NUTContext *nut, AVPacket *pkt, int frame_code)
842 AVFormatContext *s = nut->avf;
843 AVIOContext *bc = s->pb;
844 int size, stream_id, discard;
845 int64_t pts, last_IP_pts;
849 size = decode_frame_header(nut, &pts, &stream_id, &header_idx, frame_code);
853 stc = &nut->stream[stream_id];
855 if (stc->last_flags & FLAG_KEY)
856 stc->skip_until_key_frame = 0;
858 discard = s->streams[stream_id]->discard;
859 last_IP_pts = s->streams[stream_id]->last_IP_pts;
860 if ((discard >= AVDISCARD_NONKEY && !(stc->last_flags & FLAG_KEY)) ||
861 (discard >= AVDISCARD_BIDIR && last_IP_pts != AV_NOPTS_VALUE &&
862 last_IP_pts > pts) ||
863 discard >= AVDISCARD_ALL ||
864 stc->skip_until_key_frame) {
869 if (av_new_packet(pkt, size + nut->header_len[header_idx]) < 0)
870 return AVERROR(ENOMEM);
871 memcpy(pkt->data, nut->header[header_idx], nut->header_len[header_idx]);
872 pkt->pos = avio_tell(bc); // FIXME
873 avio_read(bc, pkt->data + nut->header_len[header_idx], size);
875 pkt->stream_index = stream_id;
876 if (stc->last_flags & FLAG_KEY)
877 pkt->flags |= AV_PKT_FLAG_KEY;
883 static int nut_read_packet(AVFormatContext *s, AVPacket *pkt)
885 NUTContext *nut = s->priv_data;
886 AVIOContext *bc = s->pb;
887 int i, frame_code = 0, ret, skip;
888 int64_t ts, back_ptr;
891 int64_t pos = avio_tell(bc);
892 uint64_t tmp = nut->next_startcode;
893 nut->next_startcode = 0;
898 frame_code = avio_r8(bc);
901 if (frame_code == 'N') {
903 for (i = 1; i < 8; i++)
904 tmp = (tmp << 8) + avio_r8(bc);
909 case STREAM_STARTCODE:
910 case INDEX_STARTCODE:
911 skip = get_packetheader(nut, bc, 0, tmp);
915 if (decode_info_header(nut) < 0)
918 case SYNCPOINT_STARTCODE:
919 if (decode_syncpoint(nut, &ts, &back_ptr) < 0)
921 frame_code = avio_r8(bc);
923 ret = decode_frame(nut, pkt, frame_code);
926 else if (ret == 1) // OK but discard packet
930 av_log(s, AV_LOG_DEBUG, "syncing from %"PRId64"\n", pos);
931 tmp = find_any_startcode(bc, nut->last_syncpoint_pos + 1);
933 return AVERROR_INVALIDDATA;
934 av_log(s, AV_LOG_DEBUG, "sync\n");
935 nut->next_startcode = tmp;
940 static int64_t nut_read_timestamp(AVFormatContext *s, int stream_index,
941 int64_t *pos_arg, int64_t pos_limit)
943 NUTContext *nut = s->priv_data;
944 AVIOContext *bc = s->pb;
945 int64_t pos, pts, back_ptr;
946 av_log(s, AV_LOG_DEBUG, "read_timestamp(X,%d,%"PRId64",%"PRId64")\n",
947 stream_index, *pos_arg, pos_limit);
951 pos = find_startcode(bc, SYNCPOINT_STARTCODE, pos) + 1;
953 av_log(s, AV_LOG_ERROR, "read_timestamp failed.\n");
954 return AV_NOPTS_VALUE;
956 } while (decode_syncpoint(nut, &pts, &back_ptr) < 0);
958 av_assert0(nut->last_syncpoint_pos == *pos_arg);
960 av_log(s, AV_LOG_DEBUG, "return %"PRId64" %"PRId64"\n", pts, back_ptr);
961 if (stream_index == -2)
963 av_assert0(stream_index == -1);
967 static int read_seek(AVFormatContext *s, int stream_index,
968 int64_t pts, int flags)
970 NUTContext *nut = s->priv_data;
971 AVStream *st = s->streams[stream_index];
972 Syncpoint dummy = { .ts = pts * av_q2d(st->time_base) * AV_TIME_BASE };
973 Syncpoint nopts_sp = { .ts = AV_NOPTS_VALUE, .back_ptr = AV_NOPTS_VALUE };
974 Syncpoint *sp, *next_node[2] = { &nopts_sp, &nopts_sp };
975 int64_t pos, pos2, ts;
978 if (st->index_entries) {
979 int index = av_index_search_timestamp(st, pts, flags);
981 index = av_index_search_timestamp(st, pts, flags ^ AVSEEK_FLAG_BACKWARD);
985 pos2 = st->index_entries[index].pos;
986 ts = st->index_entries[index].timestamp;
988 av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pts_cmp,
989 (void **) next_node);
990 av_log(s, AV_LOG_DEBUG, "%"PRIu64"-%"PRIu64" %"PRId64"-%"PRId64"\n",
991 next_node[0]->pos, next_node[1]->pos, next_node[0]->ts,
993 pos = ff_gen_search(s, -1, dummy.ts, next_node[0]->pos,
994 next_node[1]->pos, next_node[1]->pos,
995 next_node[0]->ts, next_node[1]->ts,
996 AVSEEK_FLAG_BACKWARD, &ts, nut_read_timestamp);
998 if (!(flags & AVSEEK_FLAG_BACKWARD)) {
999 dummy.pos = pos + 16;
1000 next_node[1] = &nopts_sp;
1001 av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp,
1002 (void **) next_node);
1003 pos2 = ff_gen_search(s, -2, dummy.pos, next_node[0]->pos,
1004 next_node[1]->pos, next_node[1]->pos,
1005 next_node[0]->back_ptr, next_node[1]->back_ptr,
1006 flags, &ts, nut_read_timestamp);
1009 // FIXME dir but I think it does not matter
1012 sp = av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp,
1016 pos2 = sp->back_ptr - 15;
1018 av_log(NULL, AV_LOG_DEBUG, "SEEKTO: %"PRId64"\n", pos2);
1019 pos = find_startcode(s->pb, SYNCPOINT_STARTCODE, pos2);
1020 avio_seek(s->pb, pos, SEEK_SET);
1021 av_log(NULL, AV_LOG_DEBUG, "SP: %"PRId64"\n", pos);
1022 if (pos2 > pos || pos2 + 15 < pos)
1023 av_log(NULL, AV_LOG_ERROR, "no syncpoint at backptr pos\n");
1024 for (i = 0; i < s->nb_streams; i++)
1025 nut->stream[i].skip_until_key_frame = 1;
1030 static int nut_read_close(AVFormatContext *s)
1032 NUTContext *nut = s->priv_data;
1035 av_freep(&nut->time_base);
1036 av_freep(&nut->stream);
1037 ff_nut_free_sp(nut);
1038 for (i = 1; i < nut->header_count; i++)
1039 av_freep(&nut->header[i]);
1044 AVInputFormat ff_nut_demuxer = {
1046 .long_name = NULL_IF_CONFIG_SMALL("NUT"),
1047 .flags = AVFMT_SEEK_TO_PTS,
1048 .priv_data_size = sizeof(NUTContext),
1049 .read_probe = nut_probe,
1050 .read_header = nut_read_header,
1051 .read_packet = nut_read_packet,
1052 .read_close = nut_read_close,
1053 .read_seek = read_seek,
1054 .extensions = "nut",
1055 .codec_tag = ff_nut_codec_tags,