/* * "NUT" Container Format demuxer * Copyright (c) 2004-2006 Michael Niedermayer * Copyright (c) 2003 Alex Beregszaszi * * This file is part of Libav. * * Libav is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * Libav is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include "libavutil/avstring.h" #include "libavutil/bswap.h" #include "libavutil/dict.h" #include "libavutil/mathematics.h" #include "libavutil/tree.h" #include "avio_internal.h" #include "nut.h" #undef NDEBUG #include <assert.h> #define NUT_MAX_STREAMS 256 /* arbitrary sanity check value */ static int get_str(AVIOContext *bc, char *string, unsigned int maxlen) { unsigned int len = ffio_read_varlen(bc); if (len && maxlen) avio_read(bc, string, FFMIN(len, maxlen)); while (len > maxlen) { avio_r8(bc); len--; } if (maxlen) string[FFMIN(len, maxlen - 1)] = 0; if (maxlen == len) return -1; else return 0; } static int64_t get_s(AVIOContext *bc) { int64_t v = ffio_read_varlen(bc) + 1; if (v & 1) return -(v >> 1); else return (v >> 1); } static uint64_t get_fourcc(AVIOContext *bc) { unsigned int len = ffio_read_varlen(bc); if (len == 2) return avio_rl16(bc); else if (len == 4) return avio_rl32(bc); else return -1; } #ifdef TRACE static inline uint64_t get_v_trace(AVIOContext *bc, char *file, char *func, int line) { uint64_t v = ffio_read_varlen(bc); av_log(NULL, AV_LOG_DEBUG, "get_v %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line); return v; } static inline int64_t get_s_trace(AVIOContext *bc, char *file, char *func, int line) { int64_t v = get_s(bc); av_log(NULL, AV_LOG_DEBUG, "get_s %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line); return v; } static inline uint64_t get_vb_trace(AVIOContext *bc, char *file, char *func, int line) { uint64_t v = get_vb(bc); av_log(NULL, AV_LOG_DEBUG, "get_vb %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line); return v; } #define ffio_read_varlen(bc) get_v_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__) #define get_s(bc) get_s_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__) #define get_vb(bc) get_vb_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__) #endif static int get_packetheader(NUTContext *nut, AVIOContext *bc, int calculate_checksum, uint64_t startcode) { int64_t size; // start = avio_tell(bc) - 8; startcode = av_be2ne64(startcode); startcode = ff_crc04C11DB7_update(0, (uint8_t*) &startcode, 8); ffio_init_checksum(bc, ff_crc04C11DB7_update, startcode); size = ffio_read_varlen(bc); if (size > 4096) avio_rb32(bc); if (ffio_get_checksum(bc) && size > 4096) return -1; ffio_init_checksum(bc, calculate_checksum ? ff_crc04C11DB7_update : NULL, 0); return size; } static uint64_t find_any_startcode(AVIOContext *bc, int64_t pos) { uint64_t state = 0; if (pos >= 0) /* Note, this may fail if the stream is not seekable, but that should * not matter, as in this case we simply start where we currently are */ avio_seek(bc, pos, SEEK_SET); while (!bc->eof_reached) { state = (state << 8) | avio_r8(bc); if ((state >> 56) != 'N') continue; switch (state) { case MAIN_STARTCODE: case STREAM_STARTCODE: case SYNCPOINT_STARTCODE: case INFO_STARTCODE: case INDEX_STARTCODE: return state; } } return 0; } /** * Find the given startcode. * @param code the startcode * @param pos the start position of the search, or -1 if the current position * @return the position of the startcode or -1 if not found */ static int64_t find_startcode(AVIOContext *bc, uint64_t code, int64_t pos) { for (;;) { uint64_t startcode = find_any_startcode(bc, pos); if (startcode == code) return avio_tell(bc) - 8; else if (startcode == 0) return -1; pos = -1; } } static int nut_probe(AVProbeData *p) { int i; uint64_t code = 0; for (i = 0; i < p->buf_size; i++) { code = (code << 8) | p->buf[i]; if (code == MAIN_STARTCODE) return AVPROBE_SCORE_MAX; } return 0; } #define GET_V(dst, check) \ tmp = ffio_read_varlen(bc); \ if (!(check)) { \ av_log(s, AV_LOG_ERROR, "Error " #dst " is (%"PRId64")\n", tmp); \ return -1; \ } \ dst = tmp; static int skip_reserved(AVIOContext *bc, int64_t pos) { pos -= avio_tell(bc); if (pos < 0) { avio_seek(bc, pos, SEEK_CUR); return -1; } else { while (pos--) avio_r8(bc); return 0; } } static int decode_main_header(NUTContext *nut) { AVFormatContext *s = nut->avf; AVIOContext *bc = s->pb; uint64_t tmp, end; unsigned int stream_count; int i, j, count; int tmp_stream, tmp_mul, tmp_pts, tmp_size, tmp_res, tmp_head_idx; end = get_packetheader(nut, bc, 1, MAIN_STARTCODE); end += avio_tell(bc); GET_V(tmp, tmp >= 2 && tmp <= 3) GET_V(stream_count, tmp > 0 && tmp <= NUT_MAX_STREAMS) nut->max_distance = ffio_read_varlen(bc); if (nut->max_distance > 65536) { av_log(s, AV_LOG_DEBUG, "max_distance %d\n", nut->max_distance); nut->max_distance = 65536; } GET_V(nut->time_base_count, tmp > 0 && tmp < INT_MAX / sizeof(AVRational)) nut->time_base = av_malloc(nut->time_base_count * sizeof(AVRational)); for (i = 0; i < nut->time_base_count; i++) { GET_V(nut->time_base[i].num, tmp > 0 && tmp < (1ULL << 31)) GET_V(nut->time_base[i].den, tmp > 0 && tmp < (1ULL << 31)) if (av_gcd(nut->time_base[i].num, nut->time_base[i].den) != 1) { av_log(s, AV_LOG_ERROR, "time base invalid\n"); return AVERROR_INVALIDDATA; } } tmp_pts = 0; tmp_mul = 1; tmp_stream = 0; tmp_head_idx = 0; for (i = 0; i < 256;) { int tmp_flags = ffio_read_varlen(bc); int tmp_fields = ffio_read_varlen(bc); if (tmp_fields > 0) tmp_pts = get_s(bc); if (tmp_fields > 1) tmp_mul = ffio_read_varlen(bc); if (tmp_fields > 2) tmp_stream = ffio_read_varlen(bc); if (tmp_fields > 3) tmp_size = ffio_read_varlen(bc); else tmp_size = 0; if (tmp_fields > 4) tmp_res = ffio_read_varlen(bc); else tmp_res = 0; if (tmp_fields > 5) count = ffio_read_varlen(bc); else count = tmp_mul - tmp_size; if (tmp_fields > 6) get_s(bc); if (tmp_fields > 7) tmp_head_idx = ffio_read_varlen(bc); while (tmp_fields-- > 8) ffio_read_varlen(bc); if (count == 0 || i + count > 256) { av_log(s, AV_LOG_ERROR, "illegal count %d at %d\n", count, i); return AVERROR_INVALIDDATA; } if (tmp_stream >= stream_count) { av_log(s, AV_LOG_ERROR, "illegal stream number\n"); return AVERROR_INVALIDDATA; } for (j = 0; j < count; j++, i++) { if (i == 'N') { nut->frame_code[i].flags = FLAG_INVALID; j--; continue; } nut->frame_code[i].flags = tmp_flags; nut->frame_code[i].pts_delta = tmp_pts; nut->frame_code[i].stream_id = tmp_stream; nut->frame_code[i].size_mul = tmp_mul; nut->frame_code[i].size_lsb = tmp_size + j; nut->frame_code[i].reserved_count = tmp_res; nut->frame_code[i].header_idx = tmp_head_idx; } } assert(nut->frame_code['N'].flags == FLAG_INVALID); if (end > avio_tell(bc) + 4) { int rem = 1024; GET_V(nut->header_count, tmp < 128U) nut->header_count++; for (i = 1; i < nut->header_count; i++) { uint8_t *hdr; GET_V(nut->header_len[i], tmp > 0 && tmp < 256); rem -= nut->header_len[i]; if (rem < 0) { av_log(s, AV_LOG_ERROR, "invalid elision header\n"); return AVERROR_INVALIDDATA; } hdr = av_malloc(nut->header_len[i]); if (!hdr) return AVERROR(ENOMEM); avio_read(bc, hdr, nut->header_len[i]); nut->header[i] = hdr; } assert(nut->header_len[0] == 0); } if (skip_reserved(bc, end) || ffio_get_checksum(bc)) { av_log(s, AV_LOG_ERROR, "main header checksum mismatch\n"); return AVERROR_INVALIDDATA; } nut->stream = av_mallocz(sizeof(StreamContext) * stream_count); for (i = 0; i < stream_count; i++) avformat_new_stream(s, NULL); return 0; } static int decode_stream_header(NUTContext *nut) { AVFormatContext *s = nut->avf; AVIOContext *bc = s->pb; StreamContext *stc; int class, stream_id; uint64_t tmp, end; AVStream *st; end = get_packetheader(nut, bc, 1, STREAM_STARTCODE); end += avio_tell(bc); GET_V(stream_id, tmp < s->nb_streams && !nut->stream[tmp].time_base); stc = &nut->stream[stream_id]; st = s->streams[stream_id]; if (!st) return AVERROR(ENOMEM); class = ffio_read_varlen(bc); tmp = get_fourcc(bc); st->codec->codec_tag = tmp; switch (class) { case 0: st->codec->codec_type = AVMEDIA_TYPE_VIDEO; st->codec->codec_id = av_codec_get_id((const AVCodecTag * const []) { ff_codec_bmp_tags, ff_nut_video_tags, 0 }, tmp); break; case 1: st->codec->codec_type = AVMEDIA_TYPE_AUDIO; st->codec->codec_id = ff_codec_get_id(ff_codec_wav_tags, tmp); break; case 2: st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE; st->codec->codec_id = ff_codec_get_id(ff_nut_subtitle_tags, tmp); break; case 3: st->codec->codec_type = AVMEDIA_TYPE_DATA; break; default: av_log(s, AV_LOG_ERROR, "unknown stream class (%d)\n", class); return -1; } if (class < 3 && st->codec->codec_id == CODEC_ID_NONE) av_log(s, AV_LOG_ERROR, "Unknown codec tag '0x%04x' for stream number %d\n", (unsigned int) tmp, stream_id); GET_V(stc->time_base_id, tmp < nut->time_base_count); GET_V(stc->msb_pts_shift, tmp < 16); stc->max_pts_distance = ffio_read_varlen(bc); GET_V(stc->decode_delay, tmp < 1000); // sanity limit, raise this if Moore's law is true st->codec->has_b_frames = stc->decode_delay; ffio_read_varlen(bc); // stream flags GET_V(st->codec->extradata_size, tmp < (1 << 30)); if (st->codec->extradata_size) { st->codec->extradata = av_mallocz(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE); avio_read(bc, st->codec->extradata, st->codec->extradata_size); } if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) { GET_V(st->codec->width, tmp > 0) GET_V(st->codec->height, tmp > 0) st->sample_aspect_ratio.num = ffio_read_varlen(bc); st->sample_aspect_ratio.den = ffio_read_varlen(bc); if ((!st->sample_aspect_ratio.num) != (!st->sample_aspect_ratio.den)) { av_log(s, AV_LOG_ERROR, "invalid aspect ratio %d/%d\n", st->sample_aspect_ratio.num, st->sample_aspect_ratio.den); return -1; } ffio_read_varlen(bc); /* csp type */ } else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) { GET_V(st->codec->sample_rate, tmp > 0) ffio_read_varlen(bc); // samplerate_den GET_V(st->codec->channels, tmp > 0) } if (skip_reserved(bc, end) || ffio_get_checksum(bc)) { av_log(s, AV_LOG_ERROR, "stream header %d checksum mismatch\n", stream_id); return -1; } stc->time_base = &nut->time_base[stc->time_base_id]; avpriv_set_pts_info(s->streams[stream_id], 63, stc->time_base->num, stc->time_base->den); return 0; } static void set_disposition_bits(AVFormatContext *avf, char *value, int stream_id) { int flag = 0, i; for (i = 0; ff_nut_dispositions[i].flag; ++i) if (!strcmp(ff_nut_dispositions[i].str, value)) flag = ff_nut_dispositions[i].flag; if (!flag) av_log(avf, AV_LOG_INFO, "unknown disposition type '%s'\n", value); for (i = 0; i < avf->nb_streams; ++i) if (stream_id == i || stream_id == -1) avf->streams[i]->disposition |= flag; } static int decode_info_header(NUTContext *nut) { AVFormatContext *s = nut->avf; AVIOContext *bc = s->pb; uint64_t tmp, chapter_start, chapter_len; unsigned int stream_id_plus1, count; int chapter_id, i; int64_t value, end; char name[256], str_value[1024], type_str[256]; const char *type; AVChapter *chapter = NULL; AVStream *st = NULL; AVDictionary **metadata = NULL; end = get_packetheader(nut, bc, 1, INFO_STARTCODE); end += avio_tell(bc); GET_V(stream_id_plus1, tmp <= s->nb_streams) chapter_id = get_s(bc); chapter_start = ffio_read_varlen(bc); chapter_len = ffio_read_varlen(bc); count = ffio_read_varlen(bc); if (chapter_id && !stream_id_plus1) { int64_t start = chapter_start / nut->time_base_count; chapter = avpriv_new_chapter(s, chapter_id, nut->time_base[chapter_start % nut->time_base_count], start, start + chapter_len, NULL); metadata = &chapter->metadata; } else if (stream_id_plus1) { st = s->streams[stream_id_plus1 - 1]; metadata = &st->metadata; } else metadata = &s->metadata; for (i = 0; i < count; i++) { get_str(bc, name, sizeof(name)); value = get_s(bc); if (value == -1) { type = "UTF-8"; get_str(bc, str_value, sizeof(str_value)); } else if (value == -2) { get_str(bc, type_str, sizeof(type_str)); type = type_str; get_str(bc, str_value, sizeof(str_value)); } else if (value == -3) { type = "s"; value = get_s(bc); } else if (value == -4) { type = "t"; value = ffio_read_varlen(bc); } else if (value < -4) { type = "r"; get_s(bc); } else { type = "v"; } if (stream_id_plus1 > s->nb_streams) { av_log(s, AV_LOG_ERROR, "invalid stream id for info packet\n"); continue; } if (!strcmp(type, "UTF-8")) { if (chapter_id == 0 && !strcmp(name, "Disposition")) { set_disposition_bits(s, str_value, stream_id_plus1 - 1); continue; } if (metadata && av_strcasecmp(name, "Uses") && av_strcasecmp(name, "Depends") && av_strcasecmp(name, "Replaces")) av_dict_set(metadata, name, str_value, 0); } } if (skip_reserved(bc, end) || ffio_get_checksum(bc)) { av_log(s, AV_LOG_ERROR, "info header checksum mismatch\n"); return -1; } return 0; } static int decode_syncpoint(NUTContext *nut, int64_t *ts, int64_t *back_ptr) { AVFormatContext *s = nut->avf; AVIOContext *bc = s->pb; int64_t end, tmp; nut->last_syncpoint_pos = avio_tell(bc) - 8; end = get_packetheader(nut, bc, 1, SYNCPOINT_STARTCODE); end += avio_tell(bc); tmp = ffio_read_varlen(bc); *back_ptr = nut->last_syncpoint_pos - 16 * ffio_read_varlen(bc); if (*back_ptr < 0) return -1; ff_nut_reset_ts(nut, nut->time_base[tmp % nut->time_base_count], tmp / nut->time_base_count); if (skip_reserved(bc, end) || ffio_get_checksum(bc)) { av_log(s, AV_LOG_ERROR, "sync point checksum mismatch\n"); return -1; } *ts = tmp / s->nb_streams * av_q2d(nut->time_base[tmp % s->nb_streams]) * AV_TIME_BASE; ff_nut_add_sp(nut, nut->last_syncpoint_pos, *back_ptr, *ts); return 0; } static int find_and_decode_index(NUTContext *nut) { AVFormatContext *s = nut->avf; AVIOContext *bc = s->pb; uint64_t tmp, end; int i, j, syncpoint_count; int64_t filesize = avio_size(bc); int64_t *syncpoints; int8_t *has_keyframe; int ret = -1; avio_seek(bc, filesize - 12, SEEK_SET); avio_seek(bc, filesize - avio_rb64(bc), SEEK_SET); if (avio_rb64(bc) != INDEX_STARTCODE) { av_log(s, AV_LOG_ERROR, "no index at the end\n"); return -1; } end = get_packetheader(nut, bc, 1, INDEX_STARTCODE); end += avio_tell(bc); ffio_read_varlen(bc); // max_pts GET_V(syncpoint_count, tmp < INT_MAX / 8 && tmp > 0) syncpoints = av_malloc(sizeof(int64_t) * syncpoint_count); has_keyframe = av_malloc(sizeof(int8_t) * (syncpoint_count + 1)); for (i = 0; i < syncpoint_count; i++) { syncpoints[i] = ffio_read_varlen(bc); if (syncpoints[i] <= 0) goto fail; if (i) syncpoints[i] += syncpoints[i - 1]; } for (i = 0; i < s->nb_streams; i++) { int64_t last_pts = -1; for (j = 0; j < syncpoint_count;) { uint64_t x = ffio_read_varlen(bc); int type = x & 1; int n = j; x >>= 1; if (type) { int flag = x & 1; x >>= 1; if (n + x >= syncpoint_count + 1) { av_log(s, AV_LOG_ERROR, "index overflow A\n"); goto fail; } while (x--) has_keyframe[n++] = flag; has_keyframe[n++] = !flag; } else { while (x != 1) { if (n >= syncpoint_count + 1) { av_log(s, AV_LOG_ERROR, "index overflow B\n"); goto fail; } has_keyframe[n++] = x & 1; x >>= 1; } } if (has_keyframe[0]) { av_log(s, AV_LOG_ERROR, "keyframe before first syncpoint in index\n"); goto fail; } assert(n <= syncpoint_count + 1); for (; j < n && j < syncpoint_count; j++) { if (has_keyframe[j]) { uint64_t B, A = ffio_read_varlen(bc); if (!A) { A = ffio_read_varlen(bc); B = ffio_read_varlen(bc); // eor_pts[j][i] = last_pts + A + B } else B = 0; av_add_index_entry(s->streams[i], 16 * syncpoints[j - 1], last_pts + A, 0, 0, AVINDEX_KEYFRAME); last_pts += A + B; } } } } if (skip_reserved(bc, end) || ffio_get_checksum(bc)) { av_log(s, AV_LOG_ERROR, "index checksum mismatch\n"); goto fail; } ret = 0; fail: av_free(syncpoints); av_free(has_keyframe); return ret; } static int nut_read_header(AVFormatContext *s) { NUTContext *nut = s->priv_data; AVIOContext *bc = s->pb; int64_t pos; int initialized_stream_count; nut->avf = s; /* main header */ pos = 0; do { pos = find_startcode(bc, MAIN_STARTCODE, pos) + 1; if (pos < 0 + 1) { av_log(s, AV_LOG_ERROR, "No main startcode found.\n"); return AVERROR_INVALIDDATA; } } while (decode_main_header(nut) < 0); /* stream headers */ pos = 0; for (initialized_stream_count = 0; initialized_stream_count < s->nb_streams;) { pos = find_startcode(bc, STREAM_STARTCODE, pos) + 1; if (pos < 0 + 1) { av_log(s, AV_LOG_ERROR, "Not all stream headers found.\n"); return AVERROR_INVALIDDATA; } if (decode_stream_header(nut) >= 0) initialized_stream_count++; } /* info headers */ pos = 0; for (;;) { uint64_t startcode = find_any_startcode(bc, pos); pos = avio_tell(bc); if (startcode == 0) { av_log(s, AV_LOG_ERROR, "EOF before video frames\n"); return AVERROR_INVALIDDATA; } else if (startcode == SYNCPOINT_STARTCODE) { nut->next_startcode = startcode; break; } else if (startcode != INFO_STARTCODE) { continue; } decode_info_header(nut); } s->data_offset = pos - 8; if (bc->seekable) { int64_t orig_pos = avio_tell(bc); find_and_decode_index(nut); avio_seek(bc, orig_pos, SEEK_SET); } assert(nut->next_startcode == SYNCPOINT_STARTCODE); ff_metadata_conv_ctx(s, NULL, ff_nut_metadata_conv); return 0; } static int decode_frame_header(NUTContext *nut, int64_t *pts, int *stream_id, uint8_t *header_idx, int frame_code) { AVFormatContext *s = nut->avf; AVIOContext *bc = s->pb; StreamContext *stc; int size, flags, size_mul, pts_delta, i, reserved_count; uint64_t tmp; if (avio_tell(bc) > nut->last_syncpoint_pos + nut->max_distance) { av_log(s, AV_LOG_ERROR, "Last frame must have been damaged %"PRId64" > %"PRId64" + %d\n", avio_tell(bc), nut->last_syncpoint_pos, nut->max_distance); return AVERROR_INVALIDDATA; } flags = nut->frame_code[frame_code].flags; size_mul = nut->frame_code[frame_code].size_mul; size = nut->frame_code[frame_code].size_lsb; *stream_id = nut->frame_code[frame_code].stream_id; pts_delta = nut->frame_code[frame_code].pts_delta; reserved_count = nut->frame_code[frame_code].reserved_count; *header_idx = nut->frame_code[frame_code].header_idx; if (flags & FLAG_INVALID) return AVERROR_INVALIDDATA; if (flags & FLAG_CODED) flags ^= ffio_read_varlen(bc); if (flags & FLAG_STREAM_ID) { GET_V(*stream_id, tmp < s->nb_streams) } stc = &nut->stream[*stream_id]; if (flags & FLAG_CODED_PTS) { int coded_pts = ffio_read_varlen(bc); // FIXME check last_pts validity? if (coded_pts < (1 << stc->msb_pts_shift)) { *pts = ff_lsb2full(stc, coded_pts); } else *pts = coded_pts - (1 << stc->msb_pts_shift); } else *pts = stc->last_pts + pts_delta; if (flags & FLAG_SIZE_MSB) size += size_mul * ffio_read_varlen(bc); if (flags & FLAG_MATCH_TIME) get_s(bc); if (flags & FLAG_HEADER_IDX) *header_idx = ffio_read_varlen(bc); if (flags & FLAG_RESERVED) reserved_count = ffio_read_varlen(bc); for (i = 0; i < reserved_count; i++) ffio_read_varlen(bc); if (*header_idx >= (unsigned)nut->header_count) { av_log(s, AV_LOG_ERROR, "header_idx invalid\n"); return AVERROR_INVALIDDATA; } if (size > 4096) *header_idx = 0; size -= nut->header_len[*header_idx]; if (flags & FLAG_CHECKSUM) { avio_rb32(bc); // FIXME check this } else if (size > 2 * nut->max_distance || FFABS(stc->last_pts - *pts) > stc->max_pts_distance) { av_log(s, AV_LOG_ERROR, "frame size > 2max_distance and no checksum\n"); return AVERROR_INVALIDDATA; } stc->last_pts = *pts; stc->last_flags = flags; return size; } static int decode_frame(NUTContext *nut, AVPacket *pkt, int frame_code) { AVFormatContext *s = nut->avf; AVIOContext *bc = s->pb; int size, stream_id, discard; int64_t pts, last_IP_pts; StreamContext *stc; uint8_t header_idx; size = decode_frame_header(nut, &pts, &stream_id, &header_idx, frame_code); if (size < 0) return size; stc = &nut->stream[stream_id]; if (stc->last_flags & FLAG_KEY) stc->skip_until_key_frame = 0; discard = s->streams[stream_id]->discard; last_IP_pts = s->streams[stream_id]->last_IP_pts; if ((discard >= AVDISCARD_NONKEY && !(stc->last_flags & FLAG_KEY)) || (discard >= AVDISCARD_BIDIR && last_IP_pts != AV_NOPTS_VALUE && last_IP_pts > pts) || discard >= AVDISCARD_ALL || stc->skip_until_key_frame) { avio_skip(bc, size); return 1; } av_new_packet(pkt, size + nut->header_len[header_idx]); memcpy(pkt->data, nut->header[header_idx], nut->header_len[header_idx]); pkt->pos = avio_tell(bc); // FIXME avio_read(bc, pkt->data + nut->header_len[header_idx], size); pkt->stream_index = stream_id; if (stc->last_flags & FLAG_KEY) pkt->flags |= AV_PKT_FLAG_KEY; pkt->pts = pts; return 0; } static int nut_read_packet(AVFormatContext *s, AVPacket *pkt) { NUTContext *nut = s->priv_data; AVIOContext *bc = s->pb; int i, frame_code = 0, ret, skip; int64_t ts, back_ptr; for (;;) { int64_t pos = avio_tell(bc); uint64_t tmp = nut->next_startcode; nut->next_startcode = 0; if (tmp) { pos -= 8; } else { frame_code = avio_r8(bc); if (bc->eof_reached) return -1; if (frame_code == 'N') { tmp = frame_code; for (i = 1; i < 8; i++) tmp = (tmp << 8) + avio_r8(bc); } } switch (tmp) { case MAIN_STARTCODE: case STREAM_STARTCODE: case INDEX_STARTCODE: skip = get_packetheader(nut, bc, 0, tmp); avio_skip(bc, skip); break; case INFO_STARTCODE: if (decode_info_header(nut) < 0) goto resync; break; case SYNCPOINT_STARTCODE: if (decode_syncpoint(nut, &ts, &back_ptr) < 0) goto resync; frame_code = avio_r8(bc); case 0: ret = decode_frame(nut, pkt, frame_code); if (ret == 0) return 0; else if (ret == 1) // OK but discard packet break; default: resync: av_log(s, AV_LOG_DEBUG, "syncing from %"PRId64"\n", pos); tmp = find_any_startcode(bc, nut->last_syncpoint_pos + 1); if (tmp == 0) return AVERROR_INVALIDDATA; av_log(s, AV_LOG_DEBUG, "sync\n"); nut->next_startcode = tmp; } } } static int64_t nut_read_timestamp(AVFormatContext *s, int stream_index, int64_t *pos_arg, int64_t pos_limit) { NUTContext *nut = s->priv_data; AVIOContext *bc = s->pb; int64_t pos, pts, back_ptr; av_log(s, AV_LOG_DEBUG, "read_timestamp(X,%d,%"PRId64",%"PRId64")\n", stream_index, *pos_arg, pos_limit); pos = *pos_arg; do { pos = find_startcode(bc, SYNCPOINT_STARTCODE, pos) + 1; if (pos < 1) { assert(nut->next_startcode == 0); av_log(s, AV_LOG_ERROR, "read_timestamp failed.\n"); return AV_NOPTS_VALUE; } } while (decode_syncpoint(nut, &pts, &back_ptr) < 0); *pos_arg = pos - 1; assert(nut->last_syncpoint_pos == *pos_arg); av_log(s, AV_LOG_DEBUG, "return %"PRId64" %"PRId64"\n", pts, back_ptr); if (stream_index == -1) return pts; else if (stream_index == -2) return back_ptr; assert(0); } static int read_seek(AVFormatContext *s, int stream_index, int64_t pts, int flags) { NUTContext *nut = s->priv_data; AVStream *st = s->streams[stream_index]; Syncpoint dummy = { .ts = pts * av_q2d(st->time_base) * AV_TIME_BASE }; Syncpoint nopts_sp = { .ts = AV_NOPTS_VALUE, .back_ptr = AV_NOPTS_VALUE }; Syncpoint *sp, *next_node[2] = { &nopts_sp, &nopts_sp }; int64_t pos, pos2, ts; int i; if (st->index_entries) { int index = av_index_search_timestamp(st, pts, flags); if (index < 0) return -1; pos2 = st->index_entries[index].pos; ts = st->index_entries[index].timestamp; } else { av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pts_cmp, (void **) next_node); av_log(s, AV_LOG_DEBUG, "%"PRIu64"-%"PRIu64" %"PRId64"-%"PRId64"\n", next_node[0]->pos, next_node[1]->pos, next_node[0]->ts, next_node[1]->ts); pos = ff_gen_search(s, -1, dummy.ts, next_node[0]->pos, next_node[1]->pos, next_node[1]->pos, next_node[0]->ts, next_node[1]->ts, AVSEEK_FLAG_BACKWARD, &ts, nut_read_timestamp); if (!(flags & AVSEEK_FLAG_BACKWARD)) { dummy.pos = pos + 16; next_node[1] = &nopts_sp; av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp, (void **) next_node); pos2 = ff_gen_search(s, -2, dummy.pos, next_node[0]->pos, next_node[1]->pos, next_node[1]->pos, next_node[0]->back_ptr, next_node[1]->back_ptr, flags, &ts, nut_read_timestamp); if (pos2 >= 0) pos = pos2; // FIXME dir but I think it does not matter } dummy.pos = pos; sp = av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp, NULL); assert(sp); pos2 = sp->back_ptr - 15; } av_log(NULL, AV_LOG_DEBUG, "SEEKTO: %"PRId64"\n", pos2); pos = find_startcode(s->pb, SYNCPOINT_STARTCODE, pos2); avio_seek(s->pb, pos, SEEK_SET); av_log(NULL, AV_LOG_DEBUG, "SP: %"PRId64"\n", pos); if (pos2 > pos || pos2 + 15 < pos) av_log(NULL, AV_LOG_ERROR, "no syncpoint at backptr pos\n"); for (i = 0; i < s->nb_streams; i++) nut->stream[i].skip_until_key_frame = 1; return 0; } static int nut_read_close(AVFormatContext *s) { NUTContext *nut = s->priv_data; int i; av_freep(&nut->time_base); av_freep(&nut->stream); ff_nut_free_sp(nut); for (i = 1; i < nut->header_count; i++) av_freep(&nut->header[i]); return 0; } AVInputFormat ff_nut_demuxer = { .name = "nut", .long_name = NULL_IF_CONFIG_SMALL("NUT format"), .priv_data_size = sizeof(NUTContext), .read_probe = nut_probe, .read_header = nut_read_header, .read_packet = nut_read_packet, .read_close = nut_read_close, .read_seek = read_seek, .extensions = "nut", .codec_tag = (const AVCodecTag * const []) { ff_codec_bmp_tags, ff_nut_video_tags, ff_codec_wav_tags, ff_nut_subtitle_tags, 0 }, };