[FFmpeg-devel] [PATCH] lavf/mov: add support for sidx fragment indexes
wm4
nfxjfg at googlemail.com
Mon Oct 5 16:27:03 CEST 2015
On Sat, 3 Oct 2015 11:57:03 -0500
Rodger Combs <rodger.combs at gmail.com> wrote:
> Fixes trac #3842
> ---
> libavformat/isom.h | 2 +
> libavformat/mov.c | 250 ++++++++++++++++++++++++++++++++++++++++++++---------
> 2 files changed, 213 insertions(+), 39 deletions(-)
>
> diff --git a/libavformat/isom.h b/libavformat/isom.h
> index aee9d6e..6e921c0 100644
> --- a/libavformat/isom.h
> +++ b/libavformat/isom.h
> @@ -103,6 +103,7 @@ typedef struct MOVSbgp {
> typedef struct MOVFragmentIndexItem {
> int64_t moof_offset;
> int64_t time;
> + int headers_read;
> } MOVFragmentIndexItem;
>
> typedef struct MOVFragmentIndex {
> @@ -197,6 +198,7 @@ typedef struct MOVContext {
> int has_looked_for_mfra;
> MOVFragmentIndex** fragment_index_data;
> unsigned fragment_index_count;
> + int fragment_index_complete;
> int atom_depth;
> unsigned int aax_mode; ///< 'aax' file has been detected
> uint8_t file_key[20];
> diff --git a/libavformat/mov.c b/libavformat/mov.c
> index da170a6..5aa7491 100644
> --- a/libavformat/mov.c
> +++ b/libavformat/mov.c
> @@ -3349,7 +3349,7 @@ static int mov_read_tfhd(MOVContext *c, AVIOContext *pb, MOVAtom atom)
> MOVFragment *frag = &c->fragment;
> MOVTrackExt *trex = NULL;
> MOVFragmentIndex* index = NULL;
> - int flags, track_id, i;
> + int flags, track_id, i, found = 0;
>
> avio_r8(pb); /* version */
> flags = avio_rb24(pb);
> @@ -3367,15 +3367,6 @@ static int mov_read_tfhd(MOVContext *c, AVIOContext *pb, MOVAtom atom)
> av_log(c->fc, AV_LOG_ERROR, "could not find corresponding trex\n");
> return AVERROR_INVALIDDATA;
> }
> - for (i = 0; i < c->fragment_index_count; i++) {
> - MOVFragmentIndex* candidate = c->fragment_index_data[i];
> - if (candidate->track_id == frag->track_id) {
> - av_log(c->fc, AV_LOG_DEBUG,
> - "found fragment index for track %u\n", frag->track_id);
> - index = candidate;
> - break;
> - }
> - }
>
> frag->base_data_offset = flags & MOV_TFHD_BASE_DATA_OFFSET ?
> avio_rb64(pb) : flags & MOV_TFHD_DEFAULT_BASE_IS_MOOF ?
> @@ -3389,23 +3380,32 @@ static int mov_read_tfhd(MOVContext *c, AVIOContext *pb, MOVAtom atom)
> frag->flags = flags & MOV_TFHD_DEFAULT_FLAGS ?
> avio_rb32(pb) : trex->flags;
> frag->time = AV_NOPTS_VALUE;
> - if (index) {
> - int i, found = 0;
> - for (i = index->current_item; i < index->item_count; i++) {
> - if (frag->implicit_offset == index->items[i].moof_offset) {
> - av_log(c->fc, AV_LOG_DEBUG, "found fragment index entry "
> - "for track %u and moof_offset %"PRId64"\n",
> - frag->track_id, index->items[i].moof_offset);
> - frag->time = index->items[i].time;
> - index->current_item = i + 1;
> - found = 1;
> + for (i = 0; i < c->fragment_index_count; i++) {
> + int j;
> + MOVFragmentIndex* candidate = c->fragment_index_data[i];
> + if (candidate->track_id == frag->track_id) {
> + av_log(c->fc, AV_LOG_DEBUG,
> + "found fragment index for track %u\n", frag->track_id);
> + index = candidate;
> + for (j = index->current_item; j < index->item_count; j++) {
> + if (frag->implicit_offset == index->items[j].moof_offset) {
> + av_log(c->fc, AV_LOG_DEBUG, "found fragment index entry "
> + "for track %u and moof_offset %"PRId64"\n",
> + frag->track_id, index->items[j].moof_offset);
> + frag->time = index->items[j].time;
> + index->current_item = j + 1;
> + found = 1;
> + break;
> + }
> }
> + if (found)
> + break;
> }
> - if (!found) {
> - av_log(c->fc, AV_LOG_WARNING, "track %u has a fragment index "
> - "but it doesn't have an (in-order) entry for moof_offset "
> - "%"PRId64"\n", frag->track_id, frag->implicit_offset);
> - }
> + }
> + if (index && !found) {
> + av_log(c->fc, AV_LOG_DEBUG, "track %u has a fragment index but "
> + "it doesn't have an (in-order) entry for moof_offset "
> + "%"PRId64"\n", frag->track_id, frag->implicit_offset);
> }
> av_log(c->fc, AV_LOG_TRACE, "frag flags 0x%x\n", frag->flags);
> return 0;
> @@ -3596,7 +3596,99 @@ static int mov_read_trun(MOVContext *c, AVIOContext *pb, MOVAtom atom)
> return AVERROR_EOF;
>
> frag->implicit_offset = offset;
> - st->duration = sc->track_end = dts + sc->time_offset;
> +
> + sc->track_end = dts + sc->time_offset;
> + if (st->duration < sc->track_end)
> + st->duration = sc->track_end;
> +
> + return 0;
> +}
> +
> +static int mov_read_sidx(MOVContext *c, AVIOContext *pb, MOVAtom atom)
> +{
> + int64_t offset = avio_tell(pb) + atom.size, pts;
> + uint8_t version;
> + unsigned i, track_id;
> + AVStream *st = NULL;
> + MOVStreamContext *sc;
> + MOVFragmentIndex *index;
> + MOVFragmentIndex **tmp;
> + AVRational timescale;
> +
> + version = avio_r8(pb);
> + if (version > 1)
> + return AVERROR_PATCHWELCOME;
> +
> + avio_rb24(pb); // flags
> +
> + track_id = avio_rb32(pb); // Reference ID
> + for (i = 0; i < c->fc->nb_streams; i++) {
> + if (c->fc->streams[i]->id == track_id) {
> + st = c->fc->streams[i];
> + break;
> + }
> + }
> + if (!st) {
> + av_log(c->fc, AV_LOG_ERROR, "could not find corresponding track id %d\n", track_id);
> + return AVERROR_INVALIDDATA;
> + }
> +
> + sc = st->priv_data;
> +
> + timescale = av_make_q(1, avio_rb32(pb));
> +
> + if (version == 0) {
> + pts = avio_rb32(pb);
> + offset += avio_rb32(pb);
> + } else {
> + pts = avio_rb64(pb);
> + offset += avio_rb64(pb);
> + }
> +
> + avio_rb16(pb); // reserved
> +
> + index = av_mallocz(sizeof(MOVFragmentIndex));
> + if (!index) {
> + return AVERROR(ENOMEM);
> + }
> +
> + index->track_id = track_id;
> +
> + index->item_count = avio_rb16(pb);
> + index->items = av_mallocz_array(
> + index->item_count, sizeof(MOVFragmentIndexItem));
> +
> + if (!index->items) {
> + av_freep(&index);
> + return AVERROR(ENOMEM);
> + }
> +
> + tmp = av_realloc_array(c->fragment_index_data,
> + c->fragment_index_count + 1,
> + sizeof(MOVFragmentIndex*));
> + if (!tmp) {
> + av_freep(&index->items);
> + av_freep(&index);
> + return AVERROR(ENOMEM);
> + }
> + c->fragment_index_data = tmp;
> + c->fragment_index_data[c->fragment_index_count++] = index;
> +
> + for (i = 0; i < index->item_count; i++) {
> + uint32_t size = avio_rb32(pb) & 0x7FFFFFFF;
> + uint32_t duration = avio_rb32(pb);
> + avio_rb32(pb); // sap_flags
> + index->items[i].moof_offset = offset;
> + index->items[i].time = av_rescale_q(pts, st->time_base, timescale);
> + offset += size;
> + pts += duration;
> + }
> +
> + st->duration = sc->track_end = pts;
> +
> + if (offset == avio_size(pb))
> + c->fragment_index_complete = 1;
> +
> return 0;
> }
>
> @@ -3854,6 +3946,7 @@ static const MOVParseTableEntry mov_default_parse_table[] = {
> { MKTAG('a','l','a','c'), mov_read_alac }, /* alac specific atom */
> { MKTAG('a','v','c','C'), mov_read_glbl },
> { MKTAG('p','a','s','p'), mov_read_pasp },
> +{ MKTAG('s','i','d','x'), mov_read_sidx },
> { MKTAG('s','t','b','l'), mov_read_default },
> { MKTAG('s','t','c','o'), mov_read_stco },
> { MKTAG('s','t','p','s'), mov_read_stps },
> @@ -3978,9 +4071,9 @@ static int mov_read_default(MOVContext *c, AVIOContext *pb, MOVAtom atom)
> return err;
> }
> if (c->found_moov && c->found_mdat &&
> - ((!pb->seekable || c->fc->flags & AVFMT_FLAG_IGNIDX) ||
> + ((!pb->seekable || c->fc->flags & AVFMT_FLAG_IGNIDX || c->fragment_index_complete) ||
> start_pos + a.size == avio_size(pb))) {
> - if (!pb->seekable || c->fc->flags & AVFMT_FLAG_IGNIDX)
> + if (!pb->seekable || c->fc->flags & AVFMT_FLAG_IGNIDX || c->fragment_index_complete)
> c->next_root_atom = start_pos + a.size;
> c->atom_depth --;
> return 0;
> @@ -4585,6 +4678,52 @@ static int should_retry(AVIOContext *pb, int error_code) {
> return 1;
> }
>
> +static int mov_switch_root(AVFormatContext *s, int64_t target)
> +{
> + MOVContext *mov = s->priv_data;
> + int i, j;
> + int already_read = 0;
> +
> + if (avio_seek(s->pb, target, SEEK_SET) != target) {
> + av_log(mov->fc, AV_LOG_ERROR, "root atom offset 0x%"PRIx64": partial file\n", target);
> + return AVERROR_INVALIDDATA;
> + }
> +
> + mov->next_root_atom = 0;
> +
> + for (i = 0; i < mov->fragment_index_count; i++) {
> + MOVFragmentIndex *index = mov->fragment_index_data[i];
> + int found = 0;
> + for (j = 0; j < index->item_count; j++) {
> + MOVFragmentIndexItem *item = &index->items[j];
> + if (found) {
> + mov->next_root_atom = item->moof_offset;
> + break; // Advance to next index in outer loop
> + } else if (item->moof_offset == target) {
> + index->current_item = FFMIN(j, index->current_item);
> + if (item->headers_read)
> + already_read = 1;
> + item->headers_read = 1;
> + found = 1;
> + }
> + }
> + if (!found)
> + index->current_item = 0;
> + }
> +
> + if (already_read)
> + return 0;
> +
> + mov->found_mdat = 0;
> +
> + if (mov_read_default(mov, s->pb, (MOVAtom){ AV_RL32("root"), INT64_MAX }) < 0 ||
> + avio_feof(s->pb))
> + return AVERROR_EOF;
> + av_log(s, AV_LOG_TRACE, "read fragments, offset 0x%"PRIx64"\n", avio_tell(s->pb));
> +
> + return 1;
> +}
> +
> static int mov_read_packet(AVFormatContext *s, AVPacket *pkt)
> {
> MOVContext *mov = s->priv_data;
> @@ -4595,19 +4734,11 @@ static int mov_read_packet(AVFormatContext *s, AVPacket *pkt)
> mov->fc = s;
> retry:
> sample = mov_find_next_sample(s, &st);
> - if (!sample) {
> - mov->found_mdat = 0;
> + if (!sample || (mov->next_root_atom && sample->pos > mov->next_root_atom)) {
> if (!mov->next_root_atom)
> return AVERROR_EOF;
> - if (avio_seek(s->pb, mov->next_root_atom, SEEK_SET) != mov->next_root_atom) {
> - av_log(mov->fc, AV_LOG_ERROR, "next root atom offset 0x%"PRIx64": partial file\n", mov->next_root_atom);
> - return AVERROR_INVALIDDATA;
> - }
> - mov->next_root_atom = 0;
> - if (mov_read_default(mov, s->pb, (MOVAtom){ AV_RL32("root"), INT64_MAX }) < 0 ||
> - avio_feof(s->pb))
> - return AVERROR_EOF;
> - av_log(s, AV_LOG_TRACE, "read fragments, offset 0x%"PRIx64"\n", avio_tell(s->pb));
> + if ((ret = mov_switch_root(s, mov->next_root_atom)) < 0)
> + return ret;
> goto retry;
> }
> sc = st->priv_data;
> @@ -4685,12 +4816,53 @@ static int mov_read_packet(AVFormatContext *s, AVPacket *pkt)
> return 0;
> }
>
> +static int mov_seek_fragment(AVFormatContext *s, AVStream *st, int64_t timestamp)
> +{
> + MOVContext *mov = s->priv_data;
> + int64_t offset = -1;
> + MOVFragmentIndex *index = NULL;
> + int i;
> +
> + if (!mov->fragment_index_count)
> + return 0;
> +
> + for (i = 0; i < mov->fragment_index_count; i++) {
> + if (mov->fragment_index_data[i]->track_id == st->id) {
> + index = mov->fragment_index_data[i];
> + break;
> + }
> + }
> + if (!index)
> + return 0;
> +
> + if (mov->fragment_index_complete) {
> + for (i = index->item_count - 1; i >= 0; i--) {
> + if (index->items[i].time <= timestamp) {
> + if (index->items[i].headers_read)
> + return 0;
> +
> + offset = index->items[i].moof_offset;
> + break;
> + }
> + }
> + }
> +
> + if (offset == -1)
> + return 0;
> +
> + return mov_switch_root(s, offset);
> +}
> +
> static int mov_seek_stream(AVFormatContext *s, AVStream *st, int64_t timestamp, int flags)
> {
> MOVStreamContext *sc = st->priv_data;
> int sample, time_sample;
> int i;
>
> + int ret = mov_seek_fragment(s, st, timestamp);
> + if (ret < 0)
> + return ret;
> +
> sample = av_index_search_timestamp(st, timestamp, flags);
> av_log(s, AV_LOG_TRACE, "stream %d, timestamp %"PRId64", sample %d\n", st->index, timestamp, sample);
> if (sample < 0 && st->nb_index_entries && timestamp < st->index_entries[0].timestamp)
What's the status of this? Can it be merged?
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