[FFmpeg-devel] [PATCH] avformat/mov: get the correct fragment stsd_id when decrypting the sample

[Steven Liu]

Zhao Zhili <quinkblack at foxmail.com> 于2022年9月16日周五 17:28写道：
>
>
> > From: Wang Yaqiang <wangyaqiang03 at kuaishou.com>
> >
> > When determining whether a packet should be decrypted,
> > should use the stsd_id of the fragment where the current packet is located.
> >
> > Signed-off-by: Wang Yaqiang <wangyaqiang03 at kuaishou.com>
> > ---
> >  libavformat/isom.h | 1 +
> >  libavformat/mov.c  | 7 ++++---
> >  2 files changed, 5 insertions(+), 3 deletions(-)
> >
> > diff --git a/libavformat/isom.h b/libavformat/isom.h
> > index fd236b985f..64fb7065d5 100644
> > --- a/libavformat/isom.h
> > +++ b/libavformat/isom.h
> > @@ -139,6 +139,7 @@ typedef struct MOVFragmentStreamInfo {
> >      int index_base;
> >      int index_entry;
> >      MOVEncryptionIndex *encryption_index;
> > +    int stsd_id; // current fragment stsd_id
> >  } MOVFragmentStreamInfo;
> >
> >  typedef struct MOVFragmentIndexItem {
> > diff --git a/libavformat/mov.c b/libavformat/mov.c
> > index 35e2271b14..a2c6a4f2a3 100644
> > --- a/libavformat/mov.c
> > +++ b/libavformat/mov.c
> > @@ -4956,9 +4956,10 @@ static int mov_read_tfhd(MOVContext *c, AVIOContext *pb, MOVAtom atom)
> >      av_log(c->fc, AV_LOG_TRACE, "frag flags 0x%x\n", frag->flags);
> >
> >      frag_stream_info = get_current_frag_stream_info(&c->frag_index);
> > -    if (frag_stream_info)
> > +    if (frag_stream_info) {
> >          frag_stream_info->next_trun_dts = AV_NOPTS_VALUE;
> > -
> > +        frag_stream_info->stsd_id = frag->stsd_id;
> > +    }
> >      return 0;
> >  }
> >
> > @@ -7223,7 +7224,7 @@ static int cenc_filter(MOVContext *mov, AVStream* st, MOVStreamContext *sc, AVPa
> >      encryption_index = NULL;
> >      if (frag_stream_info) {
> >          // Note this only supports encryption info in the first sample descriptor.
> > -        if (mov->fragment.stsd_id == 1) {
> > +        if (frag_stream_info->stsd_id == 1) {
> >              if (frag_stream_info->encryption_index) {
> >                  encrypted_index = current_index - frag_stream_info->index_base;
> >                  encryption_index = frag_stream_info->encryption_index;
>
> LGTM.

Applied


Thanks
Steven