some performance measurements

system: Matrox G200, 8MByte RAM, A7V with Duron @ 950

			16 bit depth	24 bit depth
draw_rgb_image		13.8		13.9		rgb
draw_rgb_32_image	12.6		12.7		rgb0
draw_image		-		17.2		bgr0
XPutImage		-		12.6		bgr0
XvPutImage		ca. 22		ca. 20		yuv
XvPutImage (Texture)	ca. 22		-		yuv

ExtractRGB		22.9
ExtractYUV		34.5
