[FFmpeg-devel] [Hardware Accelerator for Video and Audio]

[Måns Rullgård]

Nico Sabbi wrote:
> On Thursday 21 February 2008 10:35:10 M?ns Rullg?rd wrote:
>> "Benjamin Zores" <ben at geexbox.org> writes:
>> > On Thu, Feb 21, 2008 at 10:12 AM, kenye ye <kenyeby at gmail.com>
> wrote:
>> >>  I'm thinking of this from a usability point of view.
>> >>
>> >>  > It's a bit annoying when you have a display dedicated to
>> >>  > videos. How and where is rendered the
>> >>  > GUI/WM/anything_else_that_is_not_video ?
>> >>
>> >>   We'll provide the channel for the GUI data, i.e. OSD engine.
>> >
>> > I.e a limited 256 colours OSD engine ?
>>
>> I don't see the 256-colour connection, although I agree the idea of
>> a dedicated video output device is mad.
>
> it is crazy (think of early DVB cards with a svhs output),
> but transferring back the decoded frames may require something
> almost equally crazy: 1920x1088x30 fps x 12bpp = 752 Mb/s == 94 MB/s
>
> Even halved by means of a lossless compression it takes almost 50
> MB/sec at 30 fps, back to 100 MB/s at 60 fps, that may be a lot for
> a lower-end pc (where a dedicated decoder makes more sense)

So have the decoder card dump the frames directly to video memory.
Something has to do that write, be it the CPU or some other card.

-- 
M?ns Rullg?rd
mans at mansr.com