[FFmpeg-devel] [PATCH] Make Immersive Audio Model optional for MOV demuxing

[James Almer]

On 3/27/2024 8:55 PM, Eugene Zemtsov via ffmpeg-devel wrote:
> From: Eugene Zemtsov <eugene at chromium.org>
> 
> Signed-off-by: Eugene Zemtsov <eugene at chromium.org>
> ---
>   libavformat/mov.c | 15 ++++++++++++++-
>   1 file changed, 14 insertions(+), 1 deletion(-)
> 
> diff --git a/libavformat/mov.c b/libavformat/mov.c
> index c55778f3ef..662301bf67 100644
> --- a/libavformat/mov.c
> +++ b/libavformat/mov.c
> @@ -839,6 +839,7 @@ static int mov_read_dac3(MOVContext *c, AVIOContext *pb, MOVAtom atom)
>       return 0;
>   }
>   
> +#if CONFIG_IAMFDEC
>   static int mov_read_iacb(MOVContext *c, AVIOContext *pb, MOVAtom atom)
>   {
>       AVStream *st;
> @@ -1015,6 +1016,7 @@ fail:
>   
>       return ret;
>   }
> +#endif
>   
>   static int mov_read_dec3(MOVContext *c, AVIOContext *pb, MOVAtom atom)
>   {
> @@ -4797,6 +4799,7 @@ static void fix_timescale(MOVContext *c, MOVStreamContext *sc)
>       }
>   }
>   
> +#if CONFIG_IAMFDEC
>   static int mov_update_iamf_streams(MOVContext *c, const AVStream *st)
>   {
>       const MOVStreamContext *sc = st->priv_data;
> @@ -4840,6 +4843,7 @@ static int mov_update_iamf_streams(MOVContext *c, const AVStream *st)
>   
>       return 0;
>   }
> +#endif
>   
>   static int mov_read_trak(MOVContext *c, AVIOContext *pb, MOVAtom atom)
>   {
> @@ -4921,11 +4925,13 @@ static int mov_read_trak(MOVContext *c, AVIOContext *pb, MOVAtom atom)
>   
>       mov_build_index(c, st);
>   
> +#if CONFIG_IAMFDEC
>       if (sc->iamf) {
>           ret = mov_update_iamf_streams(c, st);
>           if (ret < 0)
>               return ret;
>       }
> +#endif
>   
>       if (sc->dref_id-1 < sc->drefs_count && sc->drefs[sc->dref_id-1].path) {
>           MOVDref *dref = &sc->drefs[sc->dref_id - 1];
> @@ -8457,7 +8463,9 @@ static const MOVParseTableEntry mov_default_parse_table[] = {
>   { MKTAG('i','p','r','p'), mov_read_iprp },
>   { MKTAG('i','i','n','f'), mov_read_iinf },
>   { MKTAG('a','m','v','e'), mov_read_amve }, /* ambient viewing environment box */
> +#if CONFIG_IAMFDEC
>   { MKTAG('i','a','c','b'), mov_read_iacb },
> +#endif
>   { 0, NULL }
>   };
>   
> @@ -8929,8 +8937,10 @@ static void mov_free_stream_context(AVFormatContext *s, AVStream *st)
>       av_freep(&sc->coll);
>       av_freep(&sc->ambient);
>   
> +#if CONFIG_IAMFDEC
>       if (sc->iamf)
>           ff_iamf_read_deinit(sc->iamf);
> +#endif
>       av_freep(&sc->iamf);
>   }
>   
> @@ -9570,6 +9580,7 @@ static int mov_read_packet(AVFormatContext *s, AVPacket *pkt)
>   
>           if (st->codecpar->codec_id == AV_CODEC_ID_EIA_608 && sample->size > 8)
>               ret = get_eia608_packet(sc->pb, pkt, sample->size);
> +#if CONFIG_IAMFDEC
>           else if (sc->iamf) {
>               int64_t pts, dts, pos, duration;
>               int flags, size = sample->size;
> @@ -9592,7 +9603,9 @@ static int mov_read_packet(AVFormatContext *s, AVPacket *pkt)
>               }
>               if (!ret)
>                   return FFERROR_REDO;
> -        } else
> +        }
> +#endif
> +        else
>               ret = av_get_packet(sc->pb, pkt, sample->size);
>           if (ret < 0) {
>               if (should_retry(sc->pb, ret)) {

Can you elaborate why you need this? In configure the mov demuxer 
selects iamfdec, so it will always be present and compiled.