Re: [Redbutton-devel] Small changes to rb for Fedora 9

[Andrea <mar...@go...>]

Simon Kilvington wrote:
> xvideo output - this has been on my todo list for a long time - if you
> want to implement it I would be very pleased ;-) you should be able to

I started, but could not find any documentation about xvideo... just 2 examples with little comment.
Could use SDL though... for which there is plenty of documentation.

> base the code on videoout_xshm - I've been thinking it may be better to
> also have a function in the videoout_* codes to overlay the MHEG scene
> on the video - if we can feed YUV frames to xvideo rather than having to
> convert them to RGB first, then it may turn out better to convert the
> MHEG scene to YUV and composite that on the YUV video then feed the
> result to xvideo - the scene will change a lot less often than the video
> so there should be a lot less RGB->YUV conversion going on
> 
> so we would basically have a function in videoout_* called something
> like "set_overlay" that gets called each time the MHEG scene changes -
> then each time we show a video frame we composite the current overlay
> on to it

I have not understood one thing: who displays the video and who displays the MHEG?

MHEGDisplay.c seems to display the MHEG
videoout_* displays the video stream.

How do they interact? I mean, do they paint on the same canvas? Is the MHEG permanent till it is 
changed?
In order to implement "set_overlay" I guess MHEG should create a bitmap which should be added to the 
video????? Every frame????
Basically: I have no idea how the overlay works... :-) But I am keen to learn.

Andrea