On Thu, 2002-05-16 at 00:51, Benjamin Herrenschmidt wrote: > > > >> That is you should have at least 2 buffers so you can asynchronously > >> DMA a frame while decoding the next frame. It makes only sense to busy > >> loop on the DMA if you are decoding faster than what you display. If this > >> is not the case, then you are just throwing CPU cycles by the window. > >> > >> The whole point of DMA is for the CPU to do something else while the > >> ATI chip is doing the transfer. > > > >The problem is that the XVideo extension is very simple (it was > >basically designed to display single images with colorspace conversion > >and scaling, nothing more), so if this scheme is possible at all with > >it, the app will have to do the hard work. > > Doesn't xv support double buffer ?
Some drivers (including r128 and radeon) do, but that just means that the current image will be displayed on the next retrace after it has been transferred to video RAM. -- Earthling Michel Dänzer (MrCooper)/ Debian GNU/Linux (powerpc) developer XFree86 and DRI project member / CS student, Free Software enthusiast -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
