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 return AVERROR(ENOMEM);
237 for (i = 0; i < nut->time_base_count; i++) {
238 GET_V(nut->time_base[i].num, tmp > 0 && tmp < (1ULL << 31));
239 GET_V(nut->time_base[i].den, tmp > 0 && tmp < (1ULL << 31));
240 if (av_gcd(nut->time_base[i].num, nut->time_base[i].den) != 1) {
241 av_log(s, AV_LOG_ERROR, "invalid time base %d/%d\n",
242 nut->time_base[i].num,
243 nut->time_base[i].den);
244 return AVERROR_INVALIDDATA;
251 for (i = 0; i < 256;) {
252 int tmp_flags = ffio_read_varlen(bc);
253 int tmp_fields = ffio_read_varlen(bc);
258 tmp_mul = ffio_read_varlen(bc);
260 tmp_stream = ffio_read_varlen(bc);
262 tmp_size = ffio_read_varlen(bc);
266 tmp_res = ffio_read_varlen(bc);
270 count = ffio_read_varlen(bc);
272 count = tmp_mul - tmp_size;
276 tmp_head_idx = ffio_read_varlen(bc);
278 while (tmp_fields-- > 8)
279 ffio_read_varlen(bc);
281 if (count == 0 || i + count > 256) {
282 av_log(s, AV_LOG_ERROR, "illegal count %d at %d\n", count, i);
283 return AVERROR_INVALIDDATA;
285 if (tmp_stream >= stream_count) {
286 av_log(s, AV_LOG_ERROR, "illegal stream number %d >= %d\n",
287 tmp_stream, stream_count);
288 return AVERROR_INVALIDDATA;
291 for (j = 0; j < count; j++, i++) {
293 nut->frame_code[i].flags = FLAG_INVALID;
297 nut->frame_code[i].flags = tmp_flags;
298 nut->frame_code[i].pts_delta = tmp_pts;
299 nut->frame_code[i].stream_id = tmp_stream;
300 nut->frame_code[i].size_mul = tmp_mul;
301 nut->frame_code[i].size_lsb = tmp_size + j;
302 nut->frame_code[i].reserved_count = tmp_res;
303 nut->frame_code[i].header_idx = tmp_head_idx;
306 assert(nut->frame_code['N'].flags == FLAG_INVALID);
308 if (end > avio_tell(bc) + 4) {
310 GET_V(nut->header_count, tmp < 128U);
312 for (i = 1; i < nut->header_count; i++) {
314 GET_V(nut->header_len[i], tmp > 0 && tmp < 256);
315 if (rem < nut->header_len[i]) {
316 av_log(s, AV_LOG_ERROR,
317 "invalid elision header %d : %d > %d\n",
318 i, nut->header_len[i], rem);
319 return AVERROR_INVALIDDATA;
321 rem -= nut->header_len[i];
322 hdr = av_malloc(nut->header_len[i]);
324 return AVERROR(ENOMEM);
325 avio_read(bc, hdr, nut->header_len[i]);
326 nut->header[i] = hdr;
328 assert(nut->header_len[0] == 0);
331 // flags had been effectively introduced in version 4
332 if (nut->version > NUT_STABLE_VERSION) {
333 nut->flags = ffio_read_varlen(bc);
336 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
337 av_log(s, AV_LOG_ERROR, "main header checksum mismatch\n");
338 return AVERROR_INVALIDDATA;
341 nut->stream = av_mallocz(sizeof(StreamContext) * stream_count);
343 return AVERROR(ENOMEM);
344 for (i = 0; i < stream_count; i++)
345 avformat_new_stream(s, NULL);
350 static int decode_stream_header(NUTContext *nut)
352 AVFormatContext *s = nut->avf;
353 AVIOContext *bc = s->pb;
355 int class, stream_id;
359 end = get_packetheader(nut, bc, 1, STREAM_STARTCODE);
360 end += avio_tell(bc);
362 GET_V(stream_id, tmp < s->nb_streams && !nut->stream[tmp].time_base);
363 stc = &nut->stream[stream_id];
364 st = s->streams[stream_id];
366 return AVERROR(ENOMEM);
368 class = ffio_read_varlen(bc);
369 tmp = get_fourcc(bc);
370 st->codec->codec_tag = tmp;
373 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
374 st->codec->codec_id = av_codec_get_id((const AVCodecTag * const []) {
382 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
383 st->codec->codec_id = av_codec_get_id((const AVCodecTag * const []) {
391 st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
392 st->codec->codec_id = ff_codec_get_id(ff_nut_subtitle_tags, tmp);
395 st->codec->codec_type = AVMEDIA_TYPE_DATA;
396 st->codec->codec_id = ff_codec_get_id(ff_nut_data_tags, tmp);
399 av_log(s, AV_LOG_ERROR, "unknown stream class (%d)\n", class);
400 return AVERROR(ENOSYS);
402 if (class < 3 && st->codec->codec_id == AV_CODEC_ID_NONE)
403 av_log(s, AV_LOG_ERROR,
404 "Unknown codec tag '0x%04x' for stream number %d\n",
405 (unsigned int) tmp, stream_id);
407 GET_V(stc->time_base_id, tmp < nut->time_base_count);
408 GET_V(stc->msb_pts_shift, tmp < 16);
409 stc->max_pts_distance = ffio_read_varlen(bc);
410 GET_V(stc->decode_delay, tmp < 1000); // sanity limit, raise this if Moore's law is true
411 ffio_read_varlen(bc); // stream flags
413 GET_V(st->codec->extradata_size, tmp < (1 << 30));
414 if (st->codec->extradata_size) {
415 st->codec->extradata = av_mallocz(st->codec->extradata_size +
416 AV_INPUT_BUFFER_PADDING_SIZE);
417 if (!st->codec->extradata)
418 return AVERROR(ENOMEM);
419 avio_read(bc, st->codec->extradata, st->codec->extradata_size);
422 if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
423 GET_V(st->codec->width, tmp > 0);
424 GET_V(st->codec->height, tmp > 0);
425 st->sample_aspect_ratio.num = ffio_read_varlen(bc);
426 st->sample_aspect_ratio.den = ffio_read_varlen(bc);
427 if ((!st->sample_aspect_ratio.num) != (!st->sample_aspect_ratio.den)) {
428 av_log(s, AV_LOG_ERROR, "invalid aspect ratio %d/%d\n",
429 st->sample_aspect_ratio.num, st->sample_aspect_ratio.den);
430 return AVERROR_INVALIDDATA;
432 ffio_read_varlen(bc); /* csp type */
433 } else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
434 GET_V(st->codec->sample_rate, tmp > 0);
435 ffio_read_varlen(bc); // samplerate_den
436 GET_V(st->codec->channels, tmp > 0);
438 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
439 av_log(s, AV_LOG_ERROR,
440 "stream header %d checksum mismatch\n", stream_id);
441 return AVERROR_INVALIDDATA;
443 stc->time_base = &nut->time_base[stc->time_base_id];
444 avpriv_set_pts_info(s->streams[stream_id], 63, stc->time_base->num,
445 stc->time_base->den);
449 static void set_disposition_bits(AVFormatContext *avf, char *value,
454 for (i = 0; ff_nut_dispositions[i].flag; ++i)
455 if (!strcmp(ff_nut_dispositions[i].str, value))
456 flag = ff_nut_dispositions[i].flag;
458 av_log(avf, AV_LOG_INFO, "unknown disposition type '%s'\n", value);
459 for (i = 0; i < avf->nb_streams; ++i)
460 if (stream_id == i || stream_id == -1)
461 avf->streams[i]->disposition |= flag;
464 static int decode_info_header(NUTContext *nut)
466 AVFormatContext *s = nut->avf;
467 AVIOContext *bc = s->pb;
468 uint64_t tmp, chapter_start, chapter_len;
469 unsigned int stream_id_plus1, count;
472 char name[256], str_value[1024], type_str[256];
474 int *event_flags = NULL;
475 AVChapter *chapter = NULL;
477 AVDictionary **metadata = NULL;
478 int metadata_flag = 0;
480 end = get_packetheader(nut, bc, 1, INFO_STARTCODE);
481 end += avio_tell(bc);
483 GET_V(stream_id_plus1, tmp <= s->nb_streams);
484 chapter_id = get_s(bc);
485 chapter_start = ffio_read_varlen(bc);
486 chapter_len = ffio_read_varlen(bc);
487 count = ffio_read_varlen(bc);
489 if (chapter_id && !stream_id_plus1) {
490 int64_t start = chapter_start / nut->time_base_count;
491 chapter = avpriv_new_chapter(s, chapter_id,
492 nut->time_base[chapter_start %
493 nut->time_base_count],
494 start, start + chapter_len, NULL);
496 av_log(s, AV_LOG_ERROR, "Could not create chapter.\n");
497 return AVERROR(ENOMEM);
499 metadata = &chapter->metadata;
500 } else if (stream_id_plus1) {
501 st = s->streams[stream_id_plus1 - 1];
502 metadata = &st->metadata;
503 event_flags = &st->event_flags;
504 metadata_flag = AVSTREAM_EVENT_FLAG_METADATA_UPDATED;
506 metadata = &s->metadata;
507 event_flags = &s->event_flags;
508 metadata_flag = AVFMT_EVENT_FLAG_METADATA_UPDATED;
511 for (i = 0; i < count; i++) {
512 get_str(bc, name, sizeof(name));
516 get_str(bc, str_value, sizeof(str_value));
517 } else if (value == -2) {
518 get_str(bc, type_str, sizeof(type_str));
520 get_str(bc, str_value, sizeof(str_value));
521 } else if (value == -3) {
524 } else if (value == -4) {
526 value = ffio_read_varlen(bc);
527 } else if (value < -4) {
534 if (stream_id_plus1 > s->nb_streams) {
535 av_log(s, AV_LOG_ERROR, "invalid stream id for info packet\n");
539 if (!strcmp(type, "UTF-8")) {
540 if (chapter_id == 0 && !strcmp(name, "Disposition")) {
541 set_disposition_bits(s, str_value, stream_id_plus1 - 1);
544 if (metadata && av_strcasecmp(name, "Uses") &&
545 av_strcasecmp(name, "Depends") && av_strcasecmp(name, "Replaces")) {
547 *event_flags |= metadata_flag;
548 av_dict_set(metadata, name, str_value, 0);
553 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
554 av_log(s, AV_LOG_ERROR, "info header checksum mismatch\n");
555 return AVERROR_INVALIDDATA;
560 static int decode_syncpoint(NUTContext *nut, int64_t *ts, int64_t *back_ptr)
562 AVFormatContext *s = nut->avf;
563 AVIOContext *bc = s->pb;
567 nut->last_syncpoint_pos = avio_tell(bc) - 8;
569 end = get_packetheader(nut, bc, 1, SYNCPOINT_STARTCODE);
570 end += avio_tell(bc);
572 tmp = ffio_read_varlen(bc);
573 *back_ptr = nut->last_syncpoint_pos - 16 * ffio_read_varlen(bc);
577 ff_nut_reset_ts(nut, nut->time_base[tmp % nut->time_base_count],
578 tmp / nut->time_base_count);
580 if (nut->flags & NUT_BROADCAST) {
581 tmp = ffio_read_varlen(bc);
582 av_log(s, AV_LOG_VERBOSE, "Syncpoint wallclock %"PRId64"\n",
583 av_rescale_q(tmp / nut->time_base_count,
584 nut->time_base[tmp % nut->time_base_count],
588 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
589 av_log(s, AV_LOG_ERROR, "sync point checksum mismatch\n");
590 return AVERROR_INVALIDDATA;
593 *ts = tmp / s->nb_streams *
594 av_q2d(nut->time_base[tmp % s->nb_streams]) * AV_TIME_BASE;
596 if ((ret = ff_nut_add_sp(nut, nut->last_syncpoint_pos, *back_ptr, *ts)) < 0)
602 static int find_and_decode_index(NUTContext *nut)
604 AVFormatContext *s = nut->avf;
605 AVIOContext *bc = s->pb;
607 int i, j, syncpoint_count;
608 int64_t filesize = avio_size(bc);
610 int8_t *has_keyframe;
611 int ret = AVERROR_INVALIDDATA;
613 avio_seek(bc, filesize - 12, SEEK_SET);
614 avio_seek(bc, filesize - avio_rb64(bc), SEEK_SET);
615 if (avio_rb64(bc) != INDEX_STARTCODE) {
616 av_log(s, AV_LOG_ERROR, "no index at the end\n");
620 end = get_packetheader(nut, bc, 1, INDEX_STARTCODE);
621 end += avio_tell(bc);
623 ffio_read_varlen(bc); // max_pts
624 GET_V(syncpoint_count, tmp < INT_MAX / 8 && tmp > 0);
625 syncpoints = av_malloc(sizeof(int64_t) * syncpoint_count);
626 has_keyframe = av_malloc(sizeof(int8_t) * (syncpoint_count + 1));
627 if (!syncpoints || !has_keyframe) {
628 ret = AVERROR(ENOMEM);
631 for (i = 0; i < syncpoint_count; i++) {
632 syncpoints[i] = ffio_read_varlen(bc);
633 if (syncpoints[i] <= 0)
636 syncpoints[i] += syncpoints[i - 1];
639 for (i = 0; i < s->nb_streams; i++) {
640 int64_t last_pts = -1;
641 for (j = 0; j < syncpoint_count;) {
642 uint64_t x = ffio_read_varlen(bc);
649 if (n + x >= syncpoint_count + 1) {
650 av_log(s, AV_LOG_ERROR, "index overflow A\n");
654 has_keyframe[n++] = flag;
655 has_keyframe[n++] = !flag;
658 if (n >= syncpoint_count + 1) {
659 av_log(s, AV_LOG_ERROR, "index overflow B\n");
662 has_keyframe[n++] = x & 1;
666 if (has_keyframe[0]) {
667 av_log(s, AV_LOG_ERROR, "keyframe before first syncpoint in index\n");
670 assert(n <= syncpoint_count + 1);
671 for (; j < n && j < syncpoint_count; j++) {
672 if (has_keyframe[j]) {
673 uint64_t B, A = ffio_read_varlen(bc);
675 A = ffio_read_varlen(bc);
676 B = ffio_read_varlen(bc);
677 // eor_pts[j][i] = last_pts + A + B
680 av_add_index_entry(s->streams[i], 16 * syncpoints[j - 1],
681 last_pts + A, 0, 0, AVINDEX_KEYFRAME);
688 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
689 av_log(s, AV_LOG_ERROR, "index checksum mismatch\n");
696 av_free(has_keyframe);
700 static int nut_read_close(AVFormatContext *s)
702 NUTContext *nut = s->priv_data;
705 av_freep(&nut->time_base);
706 av_freep(&nut->stream);
708 for (i = 1; i < nut->header_count; i++)
709 av_freep(&nut->header[i]);
714 static int nut_read_header(AVFormatContext *s)
716 NUTContext *nut = s->priv_data;
717 AVIOContext *bc = s->pb;
719 int initialized_stream_count;
726 pos = find_startcode(bc, MAIN_STARTCODE, pos) + 1;
728 av_log(s, AV_LOG_ERROR, "No main startcode found.\n");
731 } while (decode_main_header(nut) < 0);
735 for (initialized_stream_count = 0; initialized_stream_count < s->nb_streams;) {
736 pos = find_startcode(bc, STREAM_STARTCODE, pos) + 1;
738 av_log(s, AV_LOG_ERROR, "Not all stream headers found.\n");
741 if (decode_stream_header(nut) >= 0)
742 initialized_stream_count++;
748 uint64_t startcode = find_any_startcode(bc, pos);
751 if (startcode == 0) {
752 av_log(s, AV_LOG_ERROR, "EOF before video frames\n");
754 } else if (startcode == SYNCPOINT_STARTCODE) {
755 nut->next_startcode = startcode;
757 } else if (startcode != INFO_STARTCODE) {
761 decode_info_header(nut);
764 s->internal->data_offset = pos - 8;
767 int64_t orig_pos = avio_tell(bc);
768 find_and_decode_index(nut);
769 avio_seek(bc, orig_pos, SEEK_SET);
771 assert(nut->next_startcode == SYNCPOINT_STARTCODE);
773 ff_metadata_conv_ctx(s, NULL, ff_nut_metadata_conv);
780 return AVERROR_INVALIDDATA;
783 static int decode_frame_header(NUTContext *nut, int64_t *pts, int *stream_id,
784 uint8_t *header_idx, int frame_code)
786 AVFormatContext *s = nut->avf;
787 AVIOContext *bc = s->pb;
789 int size, flags, size_mul, pts_delta, i, reserved_count;
792 if (!(nut->flags & NUT_PIPE) &&
793 avio_tell(bc) > nut->last_syncpoint_pos + nut->max_distance) {
794 av_log(s, AV_LOG_ERROR,
795 "Last frame must have been damaged %"PRId64" > %"PRId64" + %d\n",
796 avio_tell(bc), nut->last_syncpoint_pos, nut->max_distance);
797 return AVERROR_INVALIDDATA;
800 flags = nut->frame_code[frame_code].flags;
801 size_mul = nut->frame_code[frame_code].size_mul;
802 size = nut->frame_code[frame_code].size_lsb;
803 *stream_id = nut->frame_code[frame_code].stream_id;
804 pts_delta = nut->frame_code[frame_code].pts_delta;
805 reserved_count = nut->frame_code[frame_code].reserved_count;
806 *header_idx = nut->frame_code[frame_code].header_idx;
808 if (flags & FLAG_INVALID)
809 return AVERROR_INVALIDDATA;
810 if (flags & FLAG_CODED)
811 flags ^= ffio_read_varlen(bc);
812 if (flags & FLAG_STREAM_ID) {
813 GET_V(*stream_id, tmp < s->nb_streams);
815 stc = &nut->stream[*stream_id];
816 if (flags & FLAG_CODED_PTS) {
817 int coded_pts = ffio_read_varlen(bc);
818 // FIXME check last_pts validity?
819 if (coded_pts < (1 << stc->msb_pts_shift)) {
820 *pts = ff_lsb2full(stc, coded_pts);
822 *pts = coded_pts - (1 << stc->msb_pts_shift);
824 *pts = stc->last_pts + pts_delta;
825 if (flags & FLAG_SIZE_MSB)
826 size += size_mul * ffio_read_varlen(bc);
827 if (flags & FLAG_MATCH_TIME)
829 if (flags & FLAG_HEADER_IDX)
830 *header_idx = ffio_read_varlen(bc);
831 if (flags & FLAG_RESERVED)
832 reserved_count = ffio_read_varlen(bc);
833 for (i = 0; i < reserved_count; i++)
834 ffio_read_varlen(bc);
836 if (*header_idx >= (unsigned)nut->header_count) {
837 av_log(s, AV_LOG_ERROR, "header_idx invalid\n");
838 return AVERROR_INVALIDDATA;
842 size -= nut->header_len[*header_idx];
844 if (flags & FLAG_CHECKSUM) {
845 avio_rb32(bc); // FIXME check this
846 } else if (!(nut->flags & NUT_PIPE) &&
847 size > 2 * nut->max_distance ||
848 FFABS(stc->last_pts - *pts) > stc->max_pts_distance) {
849 av_log(s, AV_LOG_ERROR, "frame size > 2max_distance and no checksum\n");
850 return AVERROR_INVALIDDATA;
853 stc->last_pts = *pts;
854 stc->last_flags = flags;
859 static int decode_frame(NUTContext *nut, AVPacket *pkt, int frame_code)
861 AVFormatContext *s = nut->avf;
862 AVIOContext *bc = s->pb;
863 int size, stream_id, discard, ret;
864 int64_t pts, last_IP_pts;
868 size = decode_frame_header(nut, &pts, &stream_id, &header_idx, frame_code);
872 stc = &nut->stream[stream_id];
874 if (stc->last_flags & FLAG_KEY)
875 stc->skip_until_key_frame = 0;
877 discard = s->streams[stream_id]->discard;
878 last_IP_pts = s->streams[stream_id]->last_IP_pts;
879 if ((discard >= AVDISCARD_NONKEY && !(stc->last_flags & FLAG_KEY)) ||
880 (discard >= AVDISCARD_BIDIR && last_IP_pts != AV_NOPTS_VALUE &&
881 last_IP_pts > pts) ||
882 discard >= AVDISCARD_ALL ||
883 stc->skip_until_key_frame) {
888 ret = av_new_packet(pkt, size + nut->header_len[header_idx]);
891 memcpy(pkt->data, nut->header[header_idx], nut->header_len[header_idx]);
892 pkt->pos = avio_tell(bc); // FIXME
893 avio_read(bc, pkt->data + nut->header_len[header_idx], size);
895 pkt->stream_index = stream_id;
896 if (stc->last_flags & FLAG_KEY)
897 pkt->flags |= AV_PKT_FLAG_KEY;
903 static int nut_read_packet(AVFormatContext *s, AVPacket *pkt)
905 NUTContext *nut = s->priv_data;
906 AVIOContext *bc = s->pb;
907 int i, frame_code = 0, ret, skip;
908 int64_t ts, back_ptr;
911 int64_t pos = avio_tell(bc);
912 uint64_t tmp = nut->next_startcode;
913 nut->next_startcode = 0;
918 frame_code = avio_r8(bc);
921 if (frame_code == 'N') {
923 for (i = 1; i < 8; i++)
924 tmp = (tmp << 8) + avio_r8(bc);
929 case STREAM_STARTCODE:
930 case INDEX_STARTCODE:
931 skip = get_packetheader(nut, bc, 0, tmp);
935 if (decode_info_header(nut) < 0)
938 case SYNCPOINT_STARTCODE:
939 if (decode_syncpoint(nut, &ts, &back_ptr) < 0)
941 frame_code = avio_r8(bc);
943 ret = decode_frame(nut, pkt, frame_code);
946 else if (ret == 1) // OK but discard packet
950 av_log(s, AV_LOG_DEBUG, "syncing from %"PRId64"\n", pos);
951 tmp = find_any_startcode(bc, nut->last_syncpoint_pos + 1);
953 return AVERROR_INVALIDDATA;
954 av_log(s, AV_LOG_DEBUG, "sync\n");
955 nut->next_startcode = tmp;
960 static int64_t nut_read_timestamp(AVFormatContext *s, int stream_index,
961 int64_t *pos_arg, int64_t pos_limit)
963 NUTContext *nut = s->priv_data;
964 AVIOContext *bc = s->pb;
965 int64_t pos, pts, back_ptr;
966 av_log(s, AV_LOG_DEBUG, "read_timestamp(X,%d,%"PRId64",%"PRId64")\n",
967 stream_index, *pos_arg, pos_limit);
971 pos = find_startcode(bc, SYNCPOINT_STARTCODE, pos) + 1;
973 assert(nut->next_startcode == 0);
974 av_log(s, AV_LOG_ERROR, "read_timestamp failed.\n");
975 return AV_NOPTS_VALUE;
977 } while (decode_syncpoint(nut, &pts, &back_ptr) < 0);
979 assert(nut->last_syncpoint_pos == *pos_arg);
981 av_log(s, AV_LOG_DEBUG, "return %"PRId64" %"PRId64"\n", pts, back_ptr);
982 if (stream_index == -1)
984 else if (stream_index == -2)
987 return AV_NOPTS_VALUE;
990 static int read_seek(AVFormatContext *s, int stream_index,
991 int64_t pts, int flags)
993 NUTContext *nut = s->priv_data;
994 AVStream *st = s->streams[stream_index];
995 Syncpoint dummy = { .ts = pts * av_q2d(st->time_base) * AV_TIME_BASE };
996 Syncpoint nopts_sp = { .ts = AV_NOPTS_VALUE, .back_ptr = AV_NOPTS_VALUE };
997 Syncpoint *sp, *next_node[2] = { &nopts_sp, &nopts_sp };
998 int64_t pos, pos2, ts;
1001 if (nut->flags & NUT_PIPE) {
1002 return AVERROR(ENOSYS);
1005 if (st->index_entries) {
1006 int index = av_index_search_timestamp(st, pts, flags);
1010 pos2 = st->index_entries[index].pos;
1011 ts = st->index_entries[index].timestamp;
1013 av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pts_cmp,
1014 (void **) next_node);
1015 av_log(s, AV_LOG_DEBUG, "%"PRIu64"-%"PRIu64" %"PRId64"-%"PRId64"\n",
1016 next_node[0]->pos, next_node[1]->pos, next_node[0]->ts,
1018 pos = ff_gen_search(s, -1, dummy.ts, next_node[0]->pos,
1019 next_node[1]->pos, next_node[1]->pos,
1020 next_node[0]->ts, next_node[1]->ts,
1021 AVSEEK_FLAG_BACKWARD, &ts, nut_read_timestamp);
1023 if (!(flags & AVSEEK_FLAG_BACKWARD)) {
1024 dummy.pos = pos + 16;
1025 next_node[1] = &nopts_sp;
1026 av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp,
1027 (void **) next_node);
1028 pos2 = ff_gen_search(s, -2, dummy.pos, next_node[0]->pos,
1029 next_node[1]->pos, next_node[1]->pos,
1030 next_node[0]->back_ptr, next_node[1]->back_ptr,
1031 flags, &ts, nut_read_timestamp);
1034 // FIXME dir but I think it does not matter
1037 sp = av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp,
1041 pos2 = sp->back_ptr - 15;
1043 av_log(NULL, AV_LOG_DEBUG, "SEEKTO: %"PRId64"\n", pos2);
1044 pos = find_startcode(s->pb, SYNCPOINT_STARTCODE, pos2);
1045 avio_seek(s->pb, pos, SEEK_SET);
1046 av_log(NULL, AV_LOG_DEBUG, "SP: %"PRId64"\n", pos);
1047 if (pos2 > pos || pos2 + 15 < pos)
1048 av_log(NULL, AV_LOG_ERROR, "no syncpoint at backptr pos\n");
1049 for (i = 0; i < s->nb_streams; i++)
1050 nut->stream[i].skip_until_key_frame = 1;
1055 AVInputFormat ff_nut_demuxer = {
1057 .long_name = NULL_IF_CONFIG_SMALL("NUT"),
1058 .priv_data_size = sizeof(NUTContext),
1059 .read_probe = nut_probe,
1060 .read_header = nut_read_header,
1061 .read_packet = nut_read_packet,
1062 .read_close = nut_read_close,
1063 .read_seek = read_seek,
1064 .extensions = "nut",
1065 .codec_tag = ff_nut_codec_tags,