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"
32 #define NUT_MAX_STREAMS 256 /* arbitrary sanity check value */
34 static int64_t nut_read_timestamp(AVFormatContext *s, int stream_index,
35 int64_t *pos_arg, int64_t pos_limit);
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 static inline uint64_t get_4cc_trace(AVIOContext *bc, char *file,
101 char *func, int line)
103 uint64_t v = get_fourcc(bc);
105 av_log(NULL, AV_LOG_DEBUG, "get_fourcc %5"PRId64" / %"PRIX64" in %s %s:%d\n",
106 v, v, file, func, line);
109 #define ffio_read_varlen(bc) get_v_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
110 #define get_s(bc) get_s_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
111 #define get_fourcc(bc) get_4cc_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
114 static int get_packetheader(NUTContext *nut, AVIOContext *bc,
115 int calculate_checksum, uint64_t startcode)
118 // start = avio_tell(bc) - 8;
120 startcode = av_be2ne64(startcode);
121 startcode = ff_crc04C11DB7_update(0, (uint8_t*) &startcode, 8);
123 ffio_init_checksum(bc, ff_crc04C11DB7_update, startcode);
124 size = ffio_read_varlen(bc);
127 if (ffio_get_checksum(bc) && size > 4096)
130 ffio_init_checksum(bc, calculate_checksum ? ff_crc04C11DB7_update : NULL, 0);
135 static uint64_t find_any_startcode(AVIOContext *bc, int64_t pos)
140 /* Note, this may fail if the stream is not seekable, but that should
141 * not matter, as in this case we simply start where we currently are */
142 avio_seek(bc, pos, SEEK_SET);
143 while (!url_feof(bc)) {
144 state = (state << 8) | avio_r8(bc);
145 if ((state >> 56) != 'N')
149 case STREAM_STARTCODE:
150 case SYNCPOINT_STARTCODE:
152 case INDEX_STARTCODE:
161 * Find the given startcode.
162 * @param code the startcode
163 * @param pos the start position of the search, or -1 if the current position
164 * @return the position of the startcode or -1 if not found
166 static int64_t find_startcode(AVIOContext *bc, uint64_t code, int64_t pos)
169 uint64_t startcode = find_any_startcode(bc, pos);
170 if (startcode == code)
171 return avio_tell(bc) - 8;
172 else if (startcode == 0)
178 static int nut_probe(AVProbeData *p)
183 for (i = 0; i < p->buf_size; i++) {
184 code = (code << 8) | p->buf[i];
185 if (code == MAIN_STARTCODE)
186 return AVPROBE_SCORE_MAX;
191 #define GET_V(dst, check) \
193 tmp = ffio_read_varlen(bc); \
195 av_log(s, AV_LOG_ERROR, "Error " #dst " is (%"PRId64")\n", tmp); \
201 static int skip_reserved(AVIOContext *bc, int64_t pos)
203 pos -= avio_tell(bc);
205 avio_seek(bc, pos, SEEK_CUR);
214 static int decode_main_header(NUTContext *nut)
216 AVFormatContext *s = nut->avf;
217 AVIOContext *bc = s->pb;
219 unsigned int stream_count;
221 int tmp_stream, tmp_mul, tmp_pts, tmp_size, tmp_res, tmp_head_idx;
223 end = get_packetheader(nut, bc, 1, MAIN_STARTCODE);
224 end += avio_tell(bc);
226 GET_V(tmp, tmp >= 2 && tmp <= 3);
227 GET_V(stream_count, tmp > 0 && tmp <= NUT_MAX_STREAMS);
229 nut->max_distance = ffio_read_varlen(bc);
230 if (nut->max_distance > 65536) {
231 av_log(s, AV_LOG_DEBUG, "max_distance %d\n", nut->max_distance);
232 nut->max_distance = 65536;
235 GET_V(nut->time_base_count, tmp > 0 && tmp < INT_MAX / sizeof(AVRational));
236 nut->time_base = av_malloc(nut->time_base_count * sizeof(AVRational));
238 for (i = 0; i < nut->time_base_count; i++) {
239 GET_V(nut->time_base[i].num, tmp > 0 && tmp < (1ULL << 31));
240 GET_V(nut->time_base[i].den, tmp > 0 && tmp < (1ULL << 31));
241 if (av_gcd(nut->time_base[i].num, nut->time_base[i].den) != 1) {
242 av_log(s, AV_LOG_ERROR, "time base invalid\n");
243 return AVERROR_INVALIDDATA;
250 for (i = 0; i < 256;) {
251 int tmp_flags = ffio_read_varlen(bc);
252 int tmp_fields = ffio_read_varlen(bc);
257 tmp_mul = ffio_read_varlen(bc);
259 tmp_stream = ffio_read_varlen(bc);
261 tmp_size = ffio_read_varlen(bc);
265 tmp_res = ffio_read_varlen(bc);
269 count = ffio_read_varlen(bc);
271 count = tmp_mul - tmp_size;
275 tmp_head_idx = ffio_read_varlen(bc);
277 while (tmp_fields-- > 8)
278 ffio_read_varlen(bc);
280 if (count == 0 || i + count > 256) {
281 av_log(s, AV_LOG_ERROR, "illegal count %d at %d\n", count, i);
282 return AVERROR_INVALIDDATA;
284 if (tmp_stream >= stream_count) {
285 av_log(s, AV_LOG_ERROR, "illegal stream number\n");
286 return AVERROR_INVALIDDATA;
289 for (j = 0; j < count; j++, i++) {
291 nut->frame_code[i].flags = FLAG_INVALID;
295 nut->frame_code[i].flags = tmp_flags;
296 nut->frame_code[i].pts_delta = tmp_pts;
297 nut->frame_code[i].stream_id = tmp_stream;
298 nut->frame_code[i].size_mul = tmp_mul;
299 nut->frame_code[i].size_lsb = tmp_size + j;
300 nut->frame_code[i].reserved_count = tmp_res;
301 nut->frame_code[i].header_idx = tmp_head_idx;
304 av_assert0(nut->frame_code['N'].flags == FLAG_INVALID);
306 if (end > avio_tell(bc) + 4) {
308 GET_V(nut->header_count, tmp < 128U);
310 for (i = 1; i < nut->header_count; i++) {
312 GET_V(nut->header_len[i], tmp > 0 && tmp < 256);
313 rem -= nut->header_len[i];
315 av_log(s, AV_LOG_ERROR, "invalid elision header\n");
316 return AVERROR_INVALIDDATA;
318 hdr = av_malloc(nut->header_len[i]);
320 return AVERROR(ENOMEM);
321 avio_read(bc, hdr, nut->header_len[i]);
322 nut->header[i] = hdr;
324 av_assert0(nut->header_len[0] == 0);
327 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
328 av_log(s, AV_LOG_ERROR, "main header checksum mismatch\n");
329 return AVERROR_INVALIDDATA;
332 nut->stream = av_mallocz(sizeof(StreamContext) * stream_count);
333 for (i = 0; i < stream_count; i++)
334 avformat_new_stream(s, NULL);
339 static int decode_stream_header(NUTContext *nut)
341 AVFormatContext *s = nut->avf;
342 AVIOContext *bc = s->pb;
344 int class, stream_id;
348 end = get_packetheader(nut, bc, 1, STREAM_STARTCODE);
349 end += avio_tell(bc);
351 GET_V(stream_id, tmp < s->nb_streams && !nut->stream[tmp].time_base);
352 stc = &nut->stream[stream_id];
353 st = s->streams[stream_id];
355 return AVERROR(ENOMEM);
357 class = ffio_read_varlen(bc);
358 tmp = get_fourcc(bc);
359 st->codec->codec_tag = tmp;
362 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
363 st->codec->codec_id = av_codec_get_id((const AVCodecTag * const []) {
371 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
372 st->codec->codec_id = av_codec_get_id((const AVCodecTag * const []) {
380 st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
381 st->codec->codec_id = ff_codec_get_id(ff_nut_subtitle_tags, tmp);
384 st->codec->codec_type = AVMEDIA_TYPE_DATA;
387 av_log(s, AV_LOG_ERROR, "unknown stream class (%d)\n", class);
390 if (class < 3 && st->codec->codec_id == AV_CODEC_ID_NONE)
391 av_log(s, AV_LOG_ERROR,
392 "Unknown codec tag '0x%04x' for stream number %d\n",
393 (unsigned int) tmp, stream_id);
395 GET_V(stc->time_base_id, tmp < nut->time_base_count);
396 GET_V(stc->msb_pts_shift, tmp < 16);
397 stc->max_pts_distance = ffio_read_varlen(bc);
398 GET_V(stc->decode_delay, tmp < 1000); // sanity limit, raise this if Moore's law is true
399 st->codec->has_b_frames = stc->decode_delay;
400 ffio_read_varlen(bc); // stream flags
402 GET_V(st->codec->extradata_size, tmp < (1 << 30));
403 if (st->codec->extradata_size) {
404 st->codec->extradata = av_mallocz(st->codec->extradata_size +
405 FF_INPUT_BUFFER_PADDING_SIZE);
406 avio_read(bc, st->codec->extradata, st->codec->extradata_size);
409 if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
410 GET_V(st->codec->width, tmp > 0);
411 GET_V(st->codec->height, tmp > 0);
412 st->sample_aspect_ratio.num = ffio_read_varlen(bc);
413 st->sample_aspect_ratio.den = ffio_read_varlen(bc);
414 if ((!st->sample_aspect_ratio.num) != (!st->sample_aspect_ratio.den)) {
415 av_log(s, AV_LOG_ERROR, "invalid aspect ratio %d/%d\n",
416 st->sample_aspect_ratio.num, st->sample_aspect_ratio.den);
419 ffio_read_varlen(bc); /* csp type */
420 } else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
421 GET_V(st->codec->sample_rate, tmp > 0);
422 ffio_read_varlen(bc); // samplerate_den
423 GET_V(st->codec->channels, tmp > 0);
425 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
426 av_log(s, AV_LOG_ERROR,
427 "stream header %d checksum mismatch\n", stream_id);
430 stc->time_base = &nut->time_base[stc->time_base_id];
431 avpriv_set_pts_info(s->streams[stream_id], 63, stc->time_base->num,
432 stc->time_base->den);
436 static void set_disposition_bits(AVFormatContext *avf, char *value,
441 for (i = 0; ff_nut_dispositions[i].flag; ++i)
442 if (!strcmp(ff_nut_dispositions[i].str, value))
443 flag = ff_nut_dispositions[i].flag;
445 av_log(avf, AV_LOG_INFO, "unknown disposition type '%s'\n", value);
446 for (i = 0; i < avf->nb_streams; ++i)
447 if (stream_id == i || stream_id == -1)
448 avf->streams[i]->disposition |= flag;
451 static int decode_info_header(NUTContext *nut)
453 AVFormatContext *s = nut->avf;
454 AVIOContext *bc = s->pb;
455 uint64_t tmp, chapter_start, chapter_len;
456 unsigned int stream_id_plus1, count;
459 char name[256], str_value[1024], type_str[256];
461 AVChapter *chapter = NULL;
463 AVDictionary **metadata = NULL;
465 end = get_packetheader(nut, bc, 1, INFO_STARTCODE);
466 end += avio_tell(bc);
468 GET_V(stream_id_plus1, tmp <= s->nb_streams);
469 chapter_id = get_s(bc);
470 chapter_start = ffio_read_varlen(bc);
471 chapter_len = ffio_read_varlen(bc);
472 count = ffio_read_varlen(bc);
474 if (chapter_id && !stream_id_plus1) {
475 int64_t start = chapter_start / nut->time_base_count;
476 chapter = avpriv_new_chapter(s, chapter_id,
477 nut->time_base[chapter_start %
478 nut->time_base_count],
479 start, start + chapter_len, NULL);
480 metadata = &chapter->metadata;
481 } else if (stream_id_plus1) {
482 st = s->streams[stream_id_plus1 - 1];
483 metadata = &st->metadata;
485 metadata = &s->metadata;
487 for (i = 0; i < count; i++) {
488 get_str(bc, name, sizeof(name));
492 get_str(bc, str_value, sizeof(str_value));
493 } else if (value == -2) {
494 get_str(bc, type_str, sizeof(type_str));
496 get_str(bc, str_value, sizeof(str_value));
497 } else if (value == -3) {
500 } else if (value == -4) {
502 value = ffio_read_varlen(bc);
503 } else if (value < -4) {
510 if (stream_id_plus1 > s->nb_streams) {
511 av_log(s, AV_LOG_ERROR, "invalid stream id for info packet\n");
515 if (!strcmp(type, "UTF-8")) {
516 if (chapter_id == 0 && !strcmp(name, "Disposition")) {
517 set_disposition_bits(s, str_value, stream_id_plus1 - 1);
521 if (stream_id_plus1 && !strcmp(name, "r_frame_rate")) {
522 sscanf(str_value, "%d/%d", &st->r_frame_rate.num, &st->r_frame_rate.den);
526 if (metadata && av_strcasecmp(name, "Uses") &&
527 av_strcasecmp(name, "Depends") && av_strcasecmp(name, "Replaces"))
528 av_dict_set(metadata, name, str_value, 0);
532 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
533 av_log(s, AV_LOG_ERROR, "info header checksum mismatch\n");
539 static int decode_syncpoint(NUTContext *nut, int64_t *ts, int64_t *back_ptr)
541 AVFormatContext *s = nut->avf;
542 AVIOContext *bc = s->pb;
546 nut->last_syncpoint_pos = avio_tell(bc) - 8;
548 end = get_packetheader(nut, bc, 1, SYNCPOINT_STARTCODE);
549 end += avio_tell(bc);
551 tmp = ffio_read_varlen(bc);
552 *back_ptr = nut->last_syncpoint_pos - 16 * ffio_read_varlen(bc);
556 ff_nut_reset_ts(nut, nut->time_base[tmp % nut->time_base_count],
557 tmp / nut->time_base_count);
559 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
560 av_log(s, AV_LOG_ERROR, "sync point checksum mismatch\n");
564 *ts = tmp / nut->time_base_count *
565 av_q2d(nut->time_base[tmp % nut->time_base_count]) * AV_TIME_BASE;
566 ff_nut_add_sp(nut, nut->last_syncpoint_pos, *back_ptr, *ts);
571 //FIXME calculate exactly, this is just a good approximation.
572 static int64_t find_duration(NUTContext *nut, int64_t filesize)
574 AVFormatContext *s = nut->avf;
575 int64_t duration = 0;
577 int64_t pos = FFMAX(0, filesize - 2*nut->max_distance);
579 int64_t ts = nut_read_timestamp(s, -1, &pos, INT64_MAX);
582 duration = FFMAX(duration, ts);
586 s->duration_estimation_method = AVFMT_DURATION_FROM_PTS;
590 static int find_and_decode_index(NUTContext *nut)
592 AVFormatContext *s = nut->avf;
593 AVIOContext *bc = s->pb;
595 int i, j, syncpoint_count;
596 int64_t filesize = avio_size(bc);
598 int8_t *has_keyframe;
604 avio_seek(bc, filesize - 12, SEEK_SET);
605 avio_seek(bc, filesize - avio_rb64(bc), SEEK_SET);
606 if (avio_rb64(bc) != INDEX_STARTCODE) {
607 av_log(s, AV_LOG_ERROR, "no index at the end\n");
610 s->duration = find_duration(nut, filesize);
614 end = get_packetheader(nut, bc, 1, INDEX_STARTCODE);
615 end += avio_tell(bc);
617 ffio_read_varlen(bc); // max_pts
618 GET_V(syncpoint_count, tmp < INT_MAX / 8 && tmp > 0);
619 syncpoints = av_malloc(sizeof(int64_t) * syncpoint_count);
620 has_keyframe = av_malloc(sizeof(int8_t) * (syncpoint_count + 1));
621 for (i = 0; i < syncpoint_count; i++) {
622 syncpoints[i] = ffio_read_varlen(bc);
623 if (syncpoints[i] <= 0)
626 syncpoints[i] += syncpoints[i - 1];
629 for (i = 0; i < s->nb_streams; i++) {
630 int64_t last_pts = -1;
631 for (j = 0; j < syncpoint_count;) {
632 uint64_t x = ffio_read_varlen(bc);
639 if (n + x >= syncpoint_count + 1) {
640 av_log(s, AV_LOG_ERROR, "index overflow A %d + %"PRIu64" >= %d\n", n, x, syncpoint_count + 1);
644 has_keyframe[n++] = flag;
645 has_keyframe[n++] = !flag;
648 if (n >= syncpoint_count + 1) {
649 av_log(s, AV_LOG_ERROR, "index overflow B\n");
652 has_keyframe[n++] = x & 1;
656 if (has_keyframe[0]) {
657 av_log(s, AV_LOG_ERROR, "keyframe before first syncpoint in index\n");
660 av_assert0(n <= syncpoint_count + 1);
661 for (; j < n && j < syncpoint_count; j++) {
662 if (has_keyframe[j]) {
663 uint64_t B, A = ffio_read_varlen(bc);
665 A = ffio_read_varlen(bc);
666 B = ffio_read_varlen(bc);
667 // eor_pts[j][i] = last_pts + A + B
670 av_add_index_entry(s->streams[i], 16 * syncpoints[j - 1],
671 last_pts + A, 0, 0, AVINDEX_KEYFRAME);
678 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
679 av_log(s, AV_LOG_ERROR, "index checksum mismatch\n");
686 av_free(has_keyframe);
690 static int nut_read_header(AVFormatContext *s)
692 NUTContext *nut = s->priv_data;
693 AVIOContext *bc = s->pb;
695 int initialized_stream_count;
702 pos = find_startcode(bc, MAIN_STARTCODE, pos) + 1;
704 av_log(s, AV_LOG_ERROR, "No main startcode found.\n");
705 return AVERROR_INVALIDDATA;
707 } while (decode_main_header(nut) < 0);
711 for (initialized_stream_count = 0; initialized_stream_count < s->nb_streams;) {
712 pos = find_startcode(bc, STREAM_STARTCODE, pos) + 1;
714 av_log(s, AV_LOG_ERROR, "Not all stream headers found.\n");
715 return AVERROR_INVALIDDATA;
717 if (decode_stream_header(nut) >= 0)
718 initialized_stream_count++;
724 uint64_t startcode = find_any_startcode(bc, pos);
727 if (startcode == 0) {
728 av_log(s, AV_LOG_ERROR, "EOF before video frames\n");
729 return AVERROR_INVALIDDATA;
730 } else if (startcode == SYNCPOINT_STARTCODE) {
731 nut->next_startcode = startcode;
733 } else if (startcode != INFO_STARTCODE) {
737 decode_info_header(nut);
740 s->data_offset = pos - 8;
743 int64_t orig_pos = avio_tell(bc);
744 find_and_decode_index(nut);
745 avio_seek(bc, orig_pos, SEEK_SET);
747 av_assert0(nut->next_startcode == SYNCPOINT_STARTCODE);
749 ff_metadata_conv_ctx(s, NULL, ff_nut_metadata_conv);
754 static int decode_frame_header(NUTContext *nut, int64_t *pts, int *stream_id,
755 uint8_t *header_idx, int frame_code)
757 AVFormatContext *s = nut->avf;
758 AVIOContext *bc = s->pb;
760 int size, flags, size_mul, pts_delta, i, reserved_count;
763 if (avio_tell(bc) > nut->last_syncpoint_pos + nut->max_distance) {
764 av_log(s, AV_LOG_ERROR,
765 "Last frame must have been damaged %"PRId64" > %"PRId64" + %d\n",
766 avio_tell(bc), nut->last_syncpoint_pos, nut->max_distance);
767 return AVERROR_INVALIDDATA;
770 flags = nut->frame_code[frame_code].flags;
771 size_mul = nut->frame_code[frame_code].size_mul;
772 size = nut->frame_code[frame_code].size_lsb;
773 *stream_id = nut->frame_code[frame_code].stream_id;
774 pts_delta = nut->frame_code[frame_code].pts_delta;
775 reserved_count = nut->frame_code[frame_code].reserved_count;
776 *header_idx = nut->frame_code[frame_code].header_idx;
778 if (flags & FLAG_INVALID)
779 return AVERROR_INVALIDDATA;
780 if (flags & FLAG_CODED)
781 flags ^= ffio_read_varlen(bc);
782 if (flags & FLAG_STREAM_ID) {
783 GET_V(*stream_id, tmp < s->nb_streams);
785 stc = &nut->stream[*stream_id];
786 if (flags & FLAG_CODED_PTS) {
787 int coded_pts = ffio_read_varlen(bc);
788 // FIXME check last_pts validity?
789 if (coded_pts < (1 << stc->msb_pts_shift)) {
790 *pts = ff_lsb2full(stc, coded_pts);
792 *pts = coded_pts - (1 << stc->msb_pts_shift);
794 *pts = stc->last_pts + pts_delta;
795 if (flags & FLAG_SIZE_MSB)
796 size += size_mul * ffio_read_varlen(bc);
797 if (flags & FLAG_MATCH_TIME)
799 if (flags & FLAG_HEADER_IDX)
800 *header_idx = ffio_read_varlen(bc);
801 if (flags & FLAG_RESERVED)
802 reserved_count = ffio_read_varlen(bc);
803 for (i = 0; i < reserved_count; i++)
804 ffio_read_varlen(bc);
806 if (*header_idx >= (unsigned)nut->header_count) {
807 av_log(s, AV_LOG_ERROR, "header_idx invalid\n");
808 return AVERROR_INVALIDDATA;
812 size -= nut->header_len[*header_idx];
814 if (flags & FLAG_CHECKSUM) {
815 avio_rb32(bc); // FIXME check this
816 } else if (size > 2 * nut->max_distance || FFABS(stc->last_pts - *pts) >
817 stc->max_pts_distance) {
818 av_log(s, AV_LOG_ERROR, "frame size > 2max_distance and no checksum\n");
819 return AVERROR_INVALIDDATA;
822 stc->last_pts = *pts;
823 stc->last_flags = flags;
828 static int decode_frame(NUTContext *nut, AVPacket *pkt, int frame_code)
830 AVFormatContext *s = nut->avf;
831 AVIOContext *bc = s->pb;
832 int size, stream_id, discard;
833 int64_t pts, last_IP_pts;
837 size = decode_frame_header(nut, &pts, &stream_id, &header_idx, frame_code);
841 stc = &nut->stream[stream_id];
843 if (stc->last_flags & FLAG_KEY)
844 stc->skip_until_key_frame = 0;
846 discard = s->streams[stream_id]->discard;
847 last_IP_pts = s->streams[stream_id]->last_IP_pts;
848 if ((discard >= AVDISCARD_NONKEY && !(stc->last_flags & FLAG_KEY)) ||
849 (discard >= AVDISCARD_BIDIR && last_IP_pts != AV_NOPTS_VALUE &&
850 last_IP_pts > pts) ||
851 discard >= AVDISCARD_ALL ||
852 stc->skip_until_key_frame) {
857 if (av_new_packet(pkt, size + nut->header_len[header_idx]) < 0)
858 return AVERROR(ENOMEM);
859 memcpy(pkt->data, nut->header[header_idx], nut->header_len[header_idx]);
860 pkt->pos = avio_tell(bc); // FIXME
861 avio_read(bc, pkt->data + nut->header_len[header_idx], size);
863 pkt->stream_index = stream_id;
864 if (stc->last_flags & FLAG_KEY)
865 pkt->flags |= AV_PKT_FLAG_KEY;
871 static int nut_read_packet(AVFormatContext *s, AVPacket *pkt)
873 NUTContext *nut = s->priv_data;
874 AVIOContext *bc = s->pb;
875 int i, frame_code = 0, ret, skip;
876 int64_t ts, back_ptr;
879 int64_t pos = avio_tell(bc);
880 uint64_t tmp = nut->next_startcode;
881 nut->next_startcode = 0;
886 frame_code = avio_r8(bc);
889 if (frame_code == 'N') {
891 for (i = 1; i < 8; i++)
892 tmp = (tmp << 8) + avio_r8(bc);
897 case STREAM_STARTCODE:
898 case INDEX_STARTCODE:
899 skip = get_packetheader(nut, bc, 0, tmp);
903 if (decode_info_header(nut) < 0)
906 case SYNCPOINT_STARTCODE:
907 if (decode_syncpoint(nut, &ts, &back_ptr) < 0)
909 frame_code = avio_r8(bc);
911 ret = decode_frame(nut, pkt, frame_code);
914 else if (ret == 1) // OK but discard packet
918 av_log(s, AV_LOG_DEBUG, "syncing from %"PRId64"\n", pos);
919 tmp = find_any_startcode(bc, nut->last_syncpoint_pos + 1);
921 return AVERROR_INVALIDDATA;
922 av_log(s, AV_LOG_DEBUG, "sync\n");
923 nut->next_startcode = tmp;
928 static int64_t nut_read_timestamp(AVFormatContext *s, int stream_index,
929 int64_t *pos_arg, int64_t pos_limit)
931 NUTContext *nut = s->priv_data;
932 AVIOContext *bc = s->pb;
933 int64_t pos, pts, back_ptr;
934 av_log(s, AV_LOG_DEBUG, "read_timestamp(X,%d,%"PRId64",%"PRId64")\n",
935 stream_index, *pos_arg, pos_limit);
939 pos = find_startcode(bc, SYNCPOINT_STARTCODE, pos) + 1;
941 av_log(s, AV_LOG_ERROR, "read_timestamp failed.\n");
942 return AV_NOPTS_VALUE;
944 } while (decode_syncpoint(nut, &pts, &back_ptr) < 0);
946 av_assert0(nut->last_syncpoint_pos == *pos_arg);
948 av_log(s, AV_LOG_DEBUG, "return %"PRId64" %"PRId64"\n", pts, back_ptr);
949 if (stream_index == -2)
951 av_assert0(stream_index == -1);
955 static int read_seek(AVFormatContext *s, int stream_index,
956 int64_t pts, int flags)
958 NUTContext *nut = s->priv_data;
959 AVStream *st = s->streams[stream_index];
960 Syncpoint dummy = { .ts = pts * av_q2d(st->time_base) * AV_TIME_BASE };
961 Syncpoint nopts_sp = { .ts = AV_NOPTS_VALUE, .back_ptr = AV_NOPTS_VALUE };
962 Syncpoint *sp, *next_node[2] = { &nopts_sp, &nopts_sp };
963 int64_t pos, pos2, ts;
966 if (st->index_entries) {
967 int index = av_index_search_timestamp(st, pts, flags);
969 index = av_index_search_timestamp(st, pts, flags ^ AVSEEK_FLAG_BACKWARD);
973 pos2 = st->index_entries[index].pos;
974 ts = st->index_entries[index].timestamp;
976 av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pts_cmp,
977 (void **) next_node);
978 av_log(s, AV_LOG_DEBUG, "%"PRIu64"-%"PRIu64" %"PRId64"-%"PRId64"\n",
979 next_node[0]->pos, next_node[1]->pos, next_node[0]->ts,
981 pos = ff_gen_search(s, -1, dummy.ts, next_node[0]->pos,
982 next_node[1]->pos, next_node[1]->pos,
983 next_node[0]->ts, next_node[1]->ts,
984 AVSEEK_FLAG_BACKWARD, &ts, nut_read_timestamp);
986 if (!(flags & AVSEEK_FLAG_BACKWARD)) {
987 dummy.pos = pos + 16;
988 next_node[1] = &nopts_sp;
989 av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp,
990 (void **) next_node);
991 pos2 = ff_gen_search(s, -2, dummy.pos, next_node[0]->pos,
992 next_node[1]->pos, next_node[1]->pos,
993 next_node[0]->back_ptr, next_node[1]->back_ptr,
994 flags, &ts, nut_read_timestamp);
997 // FIXME dir but I think it does not matter
1000 sp = av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp,
1004 pos2 = sp->back_ptr - 15;
1006 av_log(NULL, AV_LOG_DEBUG, "SEEKTO: %"PRId64"\n", pos2);
1007 pos = find_startcode(s->pb, SYNCPOINT_STARTCODE, pos2);
1008 avio_seek(s->pb, pos, SEEK_SET);
1009 av_log(NULL, AV_LOG_DEBUG, "SP: %"PRId64"\n", pos);
1010 if (pos2 > pos || pos2 + 15 < pos)
1011 av_log(NULL, AV_LOG_ERROR, "no syncpoint at backptr pos\n");
1012 for (i = 0; i < s->nb_streams; i++)
1013 nut->stream[i].skip_until_key_frame = 1;
1018 static int nut_read_close(AVFormatContext *s)
1020 NUTContext *nut = s->priv_data;
1023 av_freep(&nut->time_base);
1024 av_freep(&nut->stream);
1025 ff_nut_free_sp(nut);
1026 for (i = 1; i < nut->header_count; i++)
1027 av_freep(&nut->header[i]);
1032 AVInputFormat ff_nut_demuxer = {
1034 .long_name = NULL_IF_CONFIG_SMALL("NUT"),
1035 .flags = AVFMT_SEEK_TO_PTS,
1036 .priv_data_size = sizeof(NUTContext),
1037 .read_probe = nut_probe,
1038 .read_header = nut_read_header,
1039 .read_packet = nut_read_packet,
1040 .read_close = nut_read_close,
1041 .read_seek = read_seek,
1042 .extensions = "nut",
1043 .codec_tag = ff_nut_codec_tags,