[FFmpeg-devel] [PATCH] avcodec/ffv1: Only allocate ThreadFrames for the decoder

[Andreas Rheinhardt]

Andreas Rheinhardt:
> The FFV1 decoder only uses the last frame's data to conceal
> errors. The encoder does not have this problem and therefore
> only uses the current frame and none of the ThreadFrames.
> So only allocate them for the decoder.
> 
> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
> ---
>  libavcodec/ffv1.c    | 13 -------------
>  libavcodec/ffv1dec.c | 23 ++++++++++++++++++++++-
>  2 files changed, 22 insertions(+), 14 deletions(-)
> 
> diff --git a/libavcodec/ffv1.c b/libavcodec/ffv1.c
> index c8781cdaaa..b6204740ed 100644
> --- a/libavcodec/ffv1.c
> +++ b/libavcodec/ffv1.c
> @@ -43,11 +43,6 @@ av_cold int ff_ffv1_common_init(AVCodecContext *avctx)
>      s->avctx = avctx;
>      s->flags = avctx->flags;
>  
> -    s->picture.f = av_frame_alloc();
> -    s->last_picture.f = av_frame_alloc();
> -    if (!s->picture.f || !s->last_picture.f)
> -        return AVERROR(ENOMEM);
> -
>      s->width  = avctx->width;
>      s->height = avctx->height;
>  
> @@ -198,14 +193,6 @@ av_cold int ff_ffv1_close(AVCodecContext *avctx)
>      FFV1Context *s = avctx->priv_data;
>      int i, j;
>  
> -    if (s->picture.f)
> -        ff_thread_release_ext_buffer(avctx, &s->picture);
> -    av_frame_free(&s->picture.f);
> -
> -    if (s->last_picture.f)
> -        ff_thread_release_ext_buffer(avctx, &s->last_picture);
> -    av_frame_free(&s->last_picture.f);
> -
>      for (j = 0; j < s->max_slice_count; j++) {
>          FFV1Context *fs = s->slice_context[j];
>          for (i = 0; i < s->plane_count; i++) {
> diff --git a/libavcodec/ffv1dec.c b/libavcodec/ffv1dec.c
> index 794c58cc40..d4bc60a7da 100644
> --- a/libavcodec/ffv1dec.c
> +++ b/libavcodec/ffv1dec.c
> @@ -823,6 +823,11 @@ static av_cold int decode_init(AVCodecContext *avctx)
>      if ((ret = ff_ffv1_common_init(avctx)) < 0)
>          return ret;
>  
> +    f->picture.f      = av_frame_alloc();
> +    f->last_picture.f = av_frame_alloc();
> +    if (!f->picture.f || !f->last_picture.f)
> +        return AVERROR(ENOMEM);
> +
>      if (avctx->extradata_size > 0 && (ret = read_extra_header(f)) < 0)
>          return ret;
>  
> @@ -1068,6 +1073,22 @@ static int update_thread_context(AVCodecContext *dst, const AVCodecContext *src)
>  }
>  #endif
>  
> +static av_cold int ffv1_decode_close(AVCodecContext *avctx)
> +{
> +    FFV1Context *const s = avctx->priv_data;
> +
> +    if (s->picture.f) {
> +        ff_thread_release_ext_buffer(avctx, &s->picture);
> +        av_frame_free(&s->picture.f);
> +    }
> +
> +    if (s->last_picture.f) {
> +        ff_thread_release_ext_buffer(avctx, &s->last_picture);
> +        av_frame_free(&s->last_picture.f);
> +    }
> +    return ff_ffv1_close(avctx);
> +}
> +
>  const FFCodec ff_ffv1_decoder = {
>      .p.name         = "ffv1",
>      CODEC_LONG_NAME("FFmpeg video codec #1"),
> @@ -1075,7 +1096,7 @@ const FFCodec ff_ffv1_decoder = {
>      .p.id           = AV_CODEC_ID_FFV1,
>      .priv_data_size = sizeof(FFV1Context),
>      .init           = decode_init,
> -    .close          = ff_ffv1_close,
> +    .close          = ffv1_decode_close,
>      FF_CODEC_DECODE_CB(decode_frame),
>      UPDATE_THREAD_CONTEXT(update_thread_context),
>      .p.capabilities = AV_CODEC_CAP_DR1 /*| AV_CODEC_CAP_DRAW_HORIZ_BAND*/ |

Will apply this tomorrow unless there are objections.

- Andreas