[FFmpeg-devel] [PATCH] v210dec: Fix width calculation

[Reimar Döffinger]

On Sat, Nov 22, 2014 at 07:11:57PM +0000, Kieran Kunhya wrote:
> ---
>  libavcodec/v210dec.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/libavcodec/v210dec.c b/libavcodec/v210dec.c
> index ae03952..978dffe 100644
> --- a/libavcodec/v210dec.c
> +++ b/libavcodec/v210dec.c
> @@ -117,7 +117,7 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
>          const uint32_t *src = (const uint32_t*)psrc;
>          uint32_t val;
>  
> -        w = (avctx->width / 6) * 6;
> +        w = ((avctx->width - 5) / 6) * 6;

Why?
The original code is correct for v210_planar_unpack_c.
The x86 asm code unfortunately doesn't document its assumptions,
but I doubt that even for those this would be exactly right.