[Libva] libva introductory article for newbies?

[Rinat Ibragimov]

Среда,  6 февраля 2013, 13:24 +08:00 от "Xiang, Haihao" <haihao.xiang at intel.com>:
>On Tue, 2013-02-05 at 23:41 +0400, Ibragimov Rinat wrote: 
>> Hi,
>> 
>> During making attempts to use VAAPI I faced with couple of difficulties
>> and then realized I have no high-level understanding of how it should
>> be used. Philosophy of libva, if you like. Is there exists some
>> introductory article about?
>
>You can build the documentation which contains some pseudo code.

Thank you. First I tried to enable doxygen output, and got empty result, as master branch
did not have all required formatting. Staging branch contains all I need.

>
>> 
>> I don't understand why in i965 driver vaQueryImageFormats returns formats
>> in YUV-colorspace only (YV12, I420, NV12) but vaCreateImage have some code
>> with BGRA too. 
>
>The image formats returned from vaQuerySubpictureFormats() are valid to
>vaCreateImage()
>

One more question. 
Is it correct that one can not display RGB VAImage other than rendering it to YUV surface with
vaPutImage and then calling vaPutSurface? This will introduce slight quality loss and I would
prefer to avoid that.

--
Rinat