[FFmpeg-devel] [PATCH 3/3] avutil/pixfmt: Clarify the meaning of the alpha bits in rgb444 and similar formats

wm4 nfxjfg at googlemail.com
Fri Feb 6 21:49:17 CET 2015


On Fri,  6 Feb 2015 20:57:50 +0100
Michael Niedermayer <michaelni at gmx.at> wrote:

> Signed-off-by: Michael Niedermayer <michaelni at gmx.at>
> ---
>  libavutil/pixfmt.h |    8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/libavutil/pixfmt.h b/libavutil/pixfmt.h
> index cbcccb2..cee5f2c 100644
> --- a/libavutil/pixfmt.h
> +++ b/libavutil/pixfmt.h
> @@ -141,10 +141,10 @@ enum AVPixelFormat {
>  #endif
>      AV_PIX_FMT_DXVA2_VLD,    ///< HW decoding through DXVA2, Picture.data[3] contains a LPDIRECT3DSURFACE9 pointer
>  
> -    AV_PIX_FMT_RGB444LE,  ///< packed RGB 4:4:4, 16bpp, (msb)4A 4R 4G 4B(lsb), little-endian, most significant bits to 0
> -    AV_PIX_FMT_RGB444BE,  ///< packed RGB 4:4:4, 16bpp, (msb)4A 4R 4G 4B(lsb), big-endian, most significant bits to 0
> -    AV_PIX_FMT_BGR444LE,  ///< packed BGR 4:4:4, 16bpp, (msb)4A 4B 4G 4R(lsb), little-endian, most significant bits to 1
> -    AV_PIX_FMT_BGR444BE,  ///< packed BGR 4:4:4, 16bpp, (msb)4A 4B 4G 4R(lsb), big-endian, most significant bits to 1
> +    AV_PIX_FMT_RGB444LE,  ///< packed RGB 4:4:4, 16bpp, (msb)4u 4R 4G 4B(lsb), little-endian, most significant bits to 0
> +    AV_PIX_FMT_RGB444BE,  ///< packed RGB 4:4:4, 16bpp, (msb)4u 4R 4G 4B(lsb), big-endian, most significant bits to 0
> +    AV_PIX_FMT_BGR444LE,  ///< packed BGR 4:4:4, 16bpp, (msb)4u 4B 4G 4R(lsb), little-endian, most significant bits to 1
> +    AV_PIX_FMT_BGR444BE,  ///< packed BGR 4:4:4, 16bpp, (msb)4u 4B 4G 4R(lsb), big-endian, most significant bits to 1
>      AV_PIX_FMT_YA8,       ///< 8bit gray, 8bit alpha
>  
>      AV_PIX_FMT_Y400A = AV_PIX_FMT_YA8, ///< alias for AV_PIX_FMT_YA8

Doesn't explain what "u" means. Also, what does it mean by "most
significant bits to 1"?

Rest of the patches look fine to me.


More information about the ffmpeg-devel mailing list