[LAU] composing for video

[Patrick Shirkey]

On 12/02/2009 12:33 PM, Paul Davis wrote:
> On Tue, Dec 1, 2009 at 8:02 PM, Danni Coy<danni.coy at gmail.com>  wrote:
>    
>> You would be suprised. RGBA32 is used quite commonly in the compositor
>> world, usually stored as a sequence of images, with even higher precisions
>> available. Raw RGB24 is reasonably common with the video professionals I
>> know, when I questioned them about it they said that they could acheive more
>> film like colour grading than they could in any of the YUV colour spaces.
>>
>> It's probably not the best format for realtime work given the amount of data
>> that needs to be transmitted (or maybe it is), I have previously worked with
>> piping raw YUV (yuv4linux) between applications and having something like
>> jack to manage the connections would be a godsend.
>>      
> my understanding is that one of the many problems that video faces is
> that there truly is no equivalent to "32 bit floating point for
> audio". whereas this format for audio samples is pretty much
> acceptable for just about all purposes, and the ones not satisfied by
> it are corner cases, in video there are many common cases that prefer
> quite different data representations. for an audio analogy, imagine a
> JACK world where some clients wanted FFT-bin data while others wanted
> floating point encoding of PCM.
>
> until or unless someone can step up and authoritatively say "the
> interchange format for video is XXXXXX", its hard to imagine a "jack
> for video" system really working very usefully for a significant
> number of people. those who work entirely in the RGBA32 or YUV spaces
> would be happy with just that format; anyone mixing processing that is
> better suited to different formats is going to take a hell of a
> performance hit.
>    


Anyone who has those extreme requirements can probably afford to buy the 
hardware required to run the system.

2  playstation3 boxes would probably provide enough grunt to manage the 
load for converting on the fly between the formats.






Patrick Shirkey
Boost Hardware Ltd