[FFmpeg-devel] [PATCH v2 4/4] avcodec/mediacodecdec: add workaround for buggy amlogic mpeg2 decoder

[Matthieu Bouron]

On Wed, May 02, 2018 at 07:25:00PM -0700, Aman Gupta wrote:
> From: Aman Gupta <aman at tmm1.net>
> 
> ---
>  libavcodec/mediacodecdec.c | 22 +++++++++++++++++++---
>  1 file changed, 19 insertions(+), 3 deletions(-)
> 
> diff --git a/libavcodec/mediacodecdec.c b/libavcodec/mediacodecdec.c
> index 2ac22dd1f6..3a4240aa95 100644
> --- a/libavcodec/mediacodecdec.c
> +++ b/libavcodec/mediacodecdec.c
> @@ -48,6 +48,7 @@ typedef struct MediaCodecH264DecContext {
>      AVPacket buffered_pkt;
>  
>      int delay_flush;
> +    int amlogic_mpeg2_api23_workaround;
>  
>  } MediaCodecH264DecContext;
>  
> @@ -287,6 +288,7 @@ static int common_set_extradata(AVCodecContext *avctx, FFAMediaFormat *format)
>  static av_cold int mediacodec_decode_init(AVCodecContext *avctx)
>  {
>      int ret;
> +    int sdk_int;
>  
>      const char *codec_mime = NULL;
>  
> @@ -377,7 +379,17 @@ static av_cold int mediacodec_decode_init(AVCodecContext *avctx)
>          goto done;
>      }
>  
> -    av_log(avctx, AV_LOG_INFO, "MediaCodec started successfully, ret = %d\n", ret);
> +    av_log(avctx, AV_LOG_INFO,
> +           "MediaCodec started successfully: codec = %s, ret = %d\n",
> +           s->ctx->codec_name, ret);
> +
> +    sdk_int = ff_Build_SDK_INT(avctx);
> +    if (sdk_int <= 23 &&
> +        strcmp(s->ctx->codec_name, "OMX.amlogic.mpeg2.decoder.awesome") == 0) {
> +        av_log(avctx, AV_LOG_INFO, "Enabling workaround for %s on API=%d\n",
> +               s->ctx->codec_name, sdk_int);
> +        s->amlogic_mpeg2_api23_workaround = 1;
> +    }
>  
>  done:
>      if (format) {
> @@ -434,8 +446,12 @@ static int mediacodec_receive_frame(AVCodecContext *avctx, AVFrame *frame)
>                  return ret;
>              }
>  
> -            /* poll for space again */
> -            continue;
> +            if (s->amlogic_mpeg2_api23_workaround && s->buffered_pkt.size <= 0) {
> +                /* fallthrough to fetch next packet regardless of input buffer space */
> +            } else {
> +                /* poll for space again */
> +                continue;
> +            }
>          }
>  
>          /* fetch new packet or eof */
> -- 
> 2.14.2
> 

Can you describe in the commit message what the issue is with this device
?

Thanks,

-- 
Matthieu B.