Re: impostor yv12

D Richard Felker III said:
> On Wed, Feb 04, 2004 at 02:42:04AM +0200, Ivan Kalvachev wrote:
>> Hello,
>> I had send few patches and few mails to xvid people
>> regarding their handling of YV12 format.
>> In short they claimed that it is reversed and they swaped the UV
>> planes. I had tracked a bug in DSHOW and VfW handling of
>> IYUV - they had mapped it to yv12, while IYUV is the same as I420.
>> Few weaks ago I checked the image.c routines and noticed that
>> the thing are unchanged, but later i found out that the VfW/DShow issues
>> have been sorted.
>>
>> So,
>> In short the YV12 format is not the format that mplayer claims it is.
>> YV12 is in fact YVU / YCrCb /, that is in no way the default MPEG
>> standart
>> color format. As you know in MPEG 0,1,2,3 blocks are Y, Cb is #4 block,
>> Cr
>> is #5 block.
>> Yes, I know that all code over mplayer-g1 use IMGFMT_YV12 as YUV, but in
>> fact this format is the I420 or IYUV format. The real conversion is done
>> at vo_xv (in draw_slice around line 488). Same for vo_directx and
>> probably
>> all that support planar formats. I should say that now I see the reason
>> mplayer to have always U as plane[1] and V as plane[2].
>>
>> Well, I don't want to change all IMGFMT_YV12 to I420, or to IMGFMT_YUV,
>> as it is a too global change. But we should make G2 in the right way.
>> Of cource if it is not already done.
>
> RTFM, this is all nonsense. MPlayer does not care about plane order,
> except when allocating or exporting buffers for crappy external
> codecs/filters/vo's that care.
I DO RTFM and RTFS
Thx for you both explaining me things I know and explain too.
This what I say is that we always have Y U V order in planes
and YV12 should be with flag SWAPPED set becouse it have
its plains in YVU order.
I would like to avoid referencing to yv12 as defalut and normal standart.


Best Regards
   Ivan Kalvachev
  iive