[FFmpeg-devel] [PATCH] Support > 8 bit input in yuv2rgb.

[Ronald S. Bultje]

Hi,


On Wed, Nov 6, 2013 at 4:15 PM, Reimar Döffinger
<Reimar.Doeffinger at gmx.de>wrote:

> Fairly ugly but about 3x faster than the default path (tested on ARM).
>
> Signed-off-by: Reimar Döffinger <Reimar.Doeffinger at gmx.de>
> ---
>  libswscale/swscale_unscaled.c |   3 +
>  libswscale/yuv2rgb.c          | 540
> ++++++------------------------------------
>  libswscale/yuv2rgb_template.c | 458 +++++++++++++++++++++++++++++++++++
>  3 files changed, 532 insertions(+), 469 deletions(-)
>  create mode 100644 libswscale/yuv2rgb_template.c
>
> diff --git a/libswscale/swscale_unscaled.c b/libswscale/swscale_unscaled.c
> index 83086f7..4864f46 100644
> --- a/libswscale/swscale_unscaled.c
> +++ b/libswscale/swscale_unscaled.c
> @@ -1217,6 +1217,9 @@ void ff_get_unscaled_swscale(SwsContext *c)
>      }
>      /* yuv2bgr */
>      if ((srcFormat == AV_PIX_FMT_YUV420P || srcFormat ==
> AV_PIX_FMT_YUV422P ||
> +         srcFormat == AV_PIX_FMT_YUV420P9LE || srcFormat ==
> AV_PIX_FMT_YUV422P9LE ||
> +         srcFormat == AV_PIX_FMT_YUV420P10LE || srcFormat ==
> AV_PIX_FMT_YUV422P10LE ||
> +         srcFormat == AV_PIX_FMT_YUV420P16LE || srcFormat ==
> AV_PIX_FMT_YUV422P16LE ||
>           srcFormat == AV_PIX_FMT_YUVA420P) && isAnyRGB(dstFormat) &&
>          !(flags & SWS_ACCURATE_RND) && (c->dither == SWS_DITHER_BAYER ||
> c->dither == SWS_DITHER_AUTO) && !(dstH & 1)) {
>          c->swscale = ff_yuv2rgb_get_func_ptr(c);
> diff --git a/libswscale/yuv2rgb.c b/libswscale/yuv2rgb.c
> index 77c56a9..946ed79 100644
> --- a/libswscale/yuv2rgb.c
> +++ b/libswscale/yuv2rgb.c
> @@ -54,66 +54,66 @@ const int *sws_getCoefficients(int colorspace)
>  }
>
>  #define LOADCHROMA(i)                               \
> -    U = pu[i];                                      \
> -    V = pv[i];                                      \
> +    U = pu[i] >> shift;                             \
> +    V = pv[i] >> shift;                             \
>      r = (void *)c->table_rV[V+YUVRGB_TABLE_HEADROOM];
> \
>      g = (void *)(c->table_gU[U+YUVRGB_TABLE_HEADROOM] +
> c->table_gV[V+YUVRGB_TABLE_HEADROOM]);  \
>      b = (void *)c->table_bU[U+YUVRGB_TABLE_HEADROOM];



So ... I'm going to have to ask this, I'm sure you understand. Why on earth
are you using 10bits video in whatever it is you're doing if you end up
clipping it back to 8bits again? Isn't it much, much faster to just serve
8bits?

Ronald