[FFmpeg-devel] [PATCH] avcodec/vaapi_encode_vp8: Use av_clip_uintp2()

[Mark Thompson]

On 16/02/17 16:20, Michael Niedermayer wrote:
> Its used elsewhere for 2^p-1 cliping
> 
> Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
> ---
>  libavcodec/vaapi_encode_vp8.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/libavcodec/vaapi_encode_vp8.c b/libavcodec/vaapi_encode_vp8.c
> index 4a1c85e66c..3d3831c46d 100644
> --- a/libavcodec/vaapi_encode_vp8.c
> +++ b/libavcodec/vaapi_encode_vp8.c
> @@ -161,12 +161,12 @@ static av_cold int vaapi_encode_vp8_configure(AVCodecContext *avctx)
>      VAAPIEncodeContext     *ctx = avctx->priv_data;
>      VAAPIEncodeVP8Context *priv = ctx->priv_data;
>  
> -    priv->q_index_p = av_clip(avctx->global_quality, 0, 127);
> +    priv->q_index_p = av_clip_uintp2(avctx->global_quality, 7);
>      if (avctx->i_quant_factor > 0.0)
> -        priv->q_index_i = av_clip((avctx->global_quality *
> +        priv->q_index_i = av_clip_uintp2((avctx->global_quality *
>                                     avctx->i_quant_factor +
>                                     avctx->i_quant_offset) + 0.5,
> -                                  0, 127);
> +                                  7);
>      else
>          priv->q_index_i = priv->q_index_p;

IMO this makes the code less readable, not more.  It doesn't really matter to anything, though, so commit it if you really want to.

(If this is mainly objecting to the magic number being visible there then please do introduce a constant to hide it rather than making the constant smaller - VP8_QINDEX_RANGE, say, to match <https://tools.ietf.org/html/rfc6386#section-14.1>.)