[FFmpeg-devel] [PATCH] lavc/lscrdec: use ff_reget_buffer()

[James Almer]

On 2/24/2021 5:40 AM, Anton Khirnov wrote:
> It is simpler and more efficient.
> 
> Suggested-by: James Almer <jamrial at gmail.com>
> ---
>   libavcodec/lscrdec.c | 17 ++++++-----------
>   1 file changed, 6 insertions(+), 11 deletions(-)
> 
> diff --git a/libavcodec/lscrdec.c b/libavcodec/lscrdec.c
> index d5388c22ac..e706dda9da 100644
> --- a/libavcodec/lscrdec.c
> +++ b/libavcodec/lscrdec.c
> @@ -105,7 +105,7 @@ static int decode_frame_lscr(AVCodecContext *avctx,
>   {
>       LSCRContext *const s = avctx->priv_data;
>       GetByteContext *gb = &s->gb;
> -    AVFrame *frame = data;
> +    AVFrame *frame = s->last_picture;
>       int ret, nb_blocks, offset = 0;
>   
>       if (avpkt->size < 2)
> @@ -115,18 +115,14 @@ static int decode_frame_lscr(AVCodecContext *avctx,
>   
>       bytestream2_init(gb, avpkt->data, avpkt->size);
>   
> -    if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
> -        return ret;
> -
>       nb_blocks = bytestream2_get_le16(gb);
>       if (bytestream2_get_bytes_left(gb) < 2 + nb_blocks * (12 + 8))
>           return AVERROR_INVALIDDATA;
>   
> -    if (s->last_picture->data[0]) {
> -        ret = av_frame_copy(frame, s->last_picture);
> -        if (ret < 0)
> -            return ret;
> -    }
> +    ret = ff_reget_buffer(avctx, frame,
> +                          nb_blocks ? 0 : FF_REGET_BUFFER_FLAG_READONLY);
> +    if (ret < 0)
> +        return ret;
>   
>       for (int b = 0; b < nb_blocks; b++) {
>           int x, y, x2, y2, w, h, left;
> @@ -216,8 +212,7 @@ static int decode_frame_lscr(AVCodecContext *avctx,
>   
>       frame->pict_type = frame->key_frame ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
>   
> -    av_frame_unref(s->last_picture);
> -    if ((ret = av_frame_ref(s->last_picture, frame)) < 0)
> +    if ((ret = av_frame_ref(data, frame)) < 0)
>           return ret;
>   
>       *got_frame = 1;

LGTM.