On Wed, 23 Jul 2003 21:36:43 +0530, Nitin Mahajan wrote: > >1.Is this the double buffering??? Yes; while one offscreen buffer is being displayed, you draw into a second offscreen buffer. When that buffer is finished, you flip them so that the second becomes visible and the first is free for drawing.
>2.I guess can be achieved by a frame buffer to framebuffer copy using the > BitBLT engine??? > Am I right?? Not at 30 fps, no. A 1024x768 RGB24 image is 2.4 megabytes. Drawing that 30 times per second exceeds the practical capacity of the PCI bus. >3.Will this help me in achieving a frame rate of 30fps to play a > software decoded video. What application software are you using to do the drawing? Programs like xine and mplayer expect to decode their frames into an "overlay" surface, using the xvideo extension in XFree86. The applications decode the frames directly into a surface in the frame buffer outside of the visible region, usually in a YUV format. The xvideo code in the driver sets up the overlay hardware to display this on the screen. Most overlay hardware can scale the overlay image as it displays, so a 320x240 decoded movie can be viewed at 1024x768. That can be done at 30fps. -- - Tim Roberts, [EMAIL PROTECTED] Providenza & Boekelheide, Inc. _______________________________________________ Devel mailing list [EMAIL PROTECTED] http://XFree86.Org/mailman/listinfo/devel
