[FFmpeg-devel] [PATCH 4/6] lavf/mov: set AV_PKT_FLAG_DISPOSABLE from sdtp box
Sasi Inguva
isasi at google.com
Mon Feb 12 22:56:18 EET 2018
On Sun, Nov 19, 2017 at 12:46 PM, John Stebbins <jstebbins at jetheaddev.com>
wrote:
> ---
> libavformat/isom.h | 10 ++++++
> libavformat/mov.c | 92 ++++++++++++++++++++++++++++++
> ++++++++++++++++++++---
> libavformat/utils.c | 3 +-
> 3 files changed, 99 insertions(+), 6 deletions(-)
>
> diff --git a/libavformat/isom.h b/libavformat/isom.h
> index 65676fb0f5..646b31ccc7 100644
> --- a/libavformat/isom.h
> +++ b/libavformat/isom.h
> @@ -137,11 +137,19 @@ typedef struct MOVIndexRange {
> int64_t end;
> } MOVIndexRange;
>
> +typedef struct MOVIndexEntry {
> +#define MOVINDEX_DISPOSABLE 0x01
> + int8_t flags;
> +} MOVIndexEntry;
> +
> typedef struct MOVStreamContext {
> AVIOContext *pb;
> int pb_is_copied;
> int ffindex; ///< AVStream index
> int next_chunk;
> + MOVIndexEntry * mov_index_entries;
> + int nb_mov_index_entries;
> + unsigned int mov_index_allocated_size;
> unsigned int chunk_count;
> int64_t *chunk_offsets;
> unsigned int stts_count;
> @@ -166,6 +174,8 @@ typedef struct MOVStreamContext {
> int keyframe_absent;
> unsigned int keyframe_count;
> int *keyframes;
> + unsigned int frame_deps_count;
> + int *frame_deps;
>
should this be uint8_t ?
Also this will increase the memory requirement quite a bit, since we are
storing for 2 int's for every sample . If we are doing this only to find
the disposable samples then, can we just store the sample indices of the
samples which are disposable while parsing sdtp instead of having one entry
for each sample.
> int time_scale;
> int64_t time_offset; ///< time offset of the edit list entries
> int current_sample;
> diff --git a/libavformat/mov.c b/libavformat/mov.c
> index 5c9f926bce..b064708ced 100644
> --- a/libavformat/mov.c
> +++ b/libavformat/mov.c
> @@ -2680,6 +2680,43 @@ static int mov_read_stps(MOVContext *c, AVIOContext
> *pb, MOVAtom atom)
> return 0;
> }
>
> +static int mov_read_sdtp(MOVContext *c, AVIOContext *pb, MOVAtom atom)
> +{
> + AVStream *st;
> + MOVStreamContext *sc;
> + unsigned int i, entries;
> +
> + if (c->fc->nb_streams < 1)
> + return 0;
> + st = c->fc->streams[c->fc->nb_streams-1];
> + sc = st->priv_data;
> +
> + if (atom.size < 8)
> + return 0;
> +
> + avio_r8(pb); /* version */
> + avio_rb24(pb); /* flags */
> +
> + entries = atom.size - 4;
> + sc->frame_deps_count = 0;
> + sc->frame_deps = av_malloc_array(entries, sizeof(*sc->frame_deps));
> +
> + if (!sc->frame_deps)
> + return AVERROR(ENOMEM);
> +
> + for (i = 0; i < entries && !pb->eof_reached; i++) {
> + sc->frame_deps[i] = avio_r8(pb);
> + }
> +
> + sc->frame_deps_count = i;
> +
> + if (pb->eof_reached)
> + return AVERROR_EOF;
> +
> +
> + return 0;
> +}
> +
> static int mov_read_stss(MOVContext *c, AVIOContext *pb, MOVAtom atom)
> {
> AVStream *st;
> @@ -3635,15 +3672,40 @@ static void mov_build_index(MOVContext *mov,
> AVStream *st)
>
> if (!sc->sample_count || st->nb_index_entries)
> return;
> - if (sc->sample_count >= UINT_MAX / sizeof(*st->index_entries) -
> st->nb_index_entries)
> + if (sc->sample_count >= UINT_MAX / sizeof(*st->index_entries))
> return;
> - if (av_reallocp_array(&st->index_entries,
> - st->nb_index_entries + sc->sample_count,
> + if (av_reallocp_array(&st->index_entries, sc->sample_count,
> sizeof(*st->index_entries)) < 0) {
> st->nb_index_entries = 0;
> return;
> }
> - st->index_entries_allocated_size = (st->nb_index_entries +
> sc->sample_count) * sizeof(*st->index_entries);
> + st->index_entries_allocated_size = sc->sample_count *
> + sizeof(*st->index_entries);
> +
> + // realloc mov_index_entries if needed for frame dependencies
> + // or if it already exists for ctts
> + if (sc->frame_deps || sc->mov_index_entries) {
> + // make mov_index_entries the same number of entries as
> + // index_entries
> + if (av_reallocp_array(&sc->mov_index_entries,
> + sc->sample_count,
> + sizeof(*sc->mov_index_entries)) < 0) {
> + sc->nb_mov_index_entries = 0;
> + return;
> + }
> + sc->mov_index_allocated_size = sc->sample_count *
> + sizeof(*sc->mov_index_
> entries);
> +
> + if (sc->sample_count > sc->nb_mov_index_entries)
> + // In case there were samples without ctts entries,
> ensure they
> + // get zero valued entries. This ensures clips which mix
> boxes
> + // with and without ctts entries don't pickup
> uninitialized
> + // data.
> + memset(sc->mov_index_entries + sc->nb_mov_index_entries,
> 0,
> + (sc->sample_count - sc->nb_mov_index_entries) *
> + sizeof(*sc->mov_index_entries));
> + sc->nb_mov_index_entries = sc->sample_count;
> + }
>
> for (i = 0; i < sc->chunk_count; i++) {
> int64_t next_offset = i+1 < sc->chunk_count ?
> sc->chunk_offsets[i+1] : INT64_MAX;
> @@ -3664,10 +3726,14 @@ static void mov_build_index(MOVContext *mov,
> AVStream *st)
>
> for (j = 0; j < sc->stsc_data[stsc_index].count; j++) {
> int keyframe = 0;
> + int disposable = 0;
> if (current_sample >= sc->sample_count) {
> av_log(mov->fc, AV_LOG_ERROR, "wrong sample count\n");
> return;
> }
> + if (sc->frame_deps && current_sample <
> sc->frame_deps_count)
> + disposable = ((sc->frame_deps[current_sample] >> 2)
> & 3) ==
> + MOV_SAMPLE_DEPENDENCY_NO;
>
> if (!sc->keyframe_absent && (!sc->keyframe_count ||
> current_sample+key_off == sc->keyframes[stss_index])) {
> keyframe = 1;
> @@ -3697,16 +3763,22 @@ static void mov_build_index(MOVContext *mov,
> AVStream *st)
> if (sc->pseudo_stream_id == -1 ||
> sc->stsc_data[stsc_index].id - 1 ==
> sc->pseudo_stream_id) {
> AVIndexEntry *e;
> + MOVIndexEntry *me;
> if (sample_size > 0x3FFFFFFF) {
> av_log(mov->fc, AV_LOG_ERROR, "Sample size %u is
> too large\n", sample_size);
> return;
> }
> - e = &st->index_entries[st->nb_index_entries++];
> + e = &st->index_entries[st->nb_index_entries];
> e->pos = current_offset;
> e->timestamp = current_dts;
> e->size = sample_size;
> e->min_distance = distance;
> e->flags = keyframe ? AVINDEX_KEYFRAME : 0;
> + if (sc->mov_index_entries) {
> + me = &sc->mov_index_entries[st->nb_
> index_entries];
> + me->flags = disposable ? MOVINDEX_DISPOSABLE : 0;
>
why can't we reuse AVIndexEntry instead of creating a new MovIndexEntry ?
e->flags |= AV_PKT_DISPOSABLE
+ }
> + st->nb_index_entries++;
> av_log(mov->fc, AV_LOG_TRACE, "AVIndex stream %d,
> sample %u, offset %"PRIx64", dts %"PRId64", "
> "size %u, distance %u, keyframe %d\n",
> st->index, current_sample,
> current_offset, current_dts, sample_size,
> distance, keyframe);
> @@ -4073,6 +4145,7 @@ static int mov_read_trak(MOVContext *c, AVIOContext
> *pb, MOVAtom atom)
> av_freep(&sc->chunk_offsets);
> av_freep(&sc->sample_sizes);
> av_freep(&sc->keyframes);
> + av_freep(&sc->frame_deps);
> av_freep(&sc->stts_data);
> av_freep(&sc->stps_data);
> av_freep(&sc->elst_data);
> @@ -5878,6 +5951,7 @@ static const MOVParseTableEntry
> mov_default_parse_table[] = {
> { MKTAG('s','t','s','c'), mov_read_stsc },
> { MKTAG('s','t','s','d'), mov_read_stsd }, /* sample description */
> { MKTAG('s','t','s','s'), mov_read_stss }, /* sync sample */
> +{ MKTAG('s','d','t','p'), mov_read_sdtp }, /* sample dependencies */
> { MKTAG('s','t','s','z'), mov_read_stsz }, /* sample size */
> { MKTAG('s','t','t','s'), mov_read_stts },
> { MKTAG('s','t','z','2'), mov_read_stsz }, /* compact sample size */
> @@ -6308,6 +6382,7 @@ static int mov_read_close(AVFormatContext *s)
> continue;
>
> av_freep(&sc->ctts_data);
> + av_freep(&sc->mov_index_entries);
> for (j = 0; j < sc->drefs_count; j++) {
> av_freep(&sc->drefs[j].path);
> av_freep(&sc->drefs[j].dir);
> @@ -6324,6 +6399,7 @@ static int mov_read_close(AVFormatContext *s)
> av_freep(&sc->stsc_data);
> av_freep(&sc->sample_sizes);
> av_freep(&sc->keyframes);
> + av_freep(&sc->frame_deps);
> av_freep(&sc->stts_data);
> av_freep(&sc->stps_data);
> av_freep(&sc->elst_data);
> @@ -6810,6 +6886,7 @@ static int mov_read_packet(AVFormatContext *s,
> AVPacket *pkt)
> MOVContext *mov = s->priv_data;
> MOVStreamContext *sc;
> AVIndexEntry *sample;
> + MOVIndexEntry *movsample = NULL;
> AVStream *st = NULL;
> int64_t current_index;
> int ret;
> @@ -6824,6 +6901,8 @@ static int mov_read_packet(AVFormatContext *s,
> AVPacket *pkt)
> goto retry;
> }
> sc = st->priv_data;
> + if (sc->current_sample < sc->nb_mov_index_entries)
> + movsample = &sc->mov_index_entries[sc->current_sample];
> /* must be done just before reading, to avoid infinite loop on sample
> */
> current_index = sc->current_index;
> mov_current_sample_inc(sc);
> @@ -6906,6 +6985,9 @@ static int mov_read_packet(AVFormatContext *s,
> AVPacket *pkt)
> if (st->discard == AVDISCARD_ALL)
> goto retry;
> pkt->flags |= sample->flags & AVINDEX_KEYFRAME ? AV_PKT_FLAG_KEY : 0;
> + if (movsample)
> + pkt->flags |= movsample->flags & MOVINDEX_DISPOSABLE ?
> + AV_PKT_FLAG_DISPOSABLE : 0;
> pkt->pos = sample->pos;
>
> /* Multiple stsd handling. */
> diff --git a/libavformat/utils.c b/libavformat/utils.c
> index ff5e14df6c..a1aa8ac6a7 100644
> --- a/libavformat/utils.c
> +++ b/libavformat/utils.c
> @@ -1458,7 +1458,8 @@ static int parse_packet(AVFormatContext *s, AVPacket
> *pkt, int stream_index)
> out_pkt.pts = st->parser->pts;
> out_pkt.dts = st->parser->dts;
> out_pkt.pos = st->parser->pos;
> - out_pkt.flags |= pkt->flags & AV_PKT_FLAG_DISCARD;
> + out_pkt.flags |= pkt->flags & (AV_PKT_FLAG_DISCARD |
> + AV_PKT_FLAG_DISPOSABLE);
>
> if (st->need_parsing == AVSTREAM_PARSE_FULL_RAW)
> out_pkt.pos = st->parser->frame_offset;
> --
> 2.13.6
>
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