When I analyze a sequence of SMPT ntsc SD color bars generated by my DV camera. The Waveform correctly indicates that the black bands are at 7.5 IRE but places the white band at around 92 IRE instead of 100 IRE and the colored bands around 70 IRE instead of 75 IRE... This in a project in DV ntsc YUV 720x480 format with the preferences "YUV colors space" to BT601 and "YUV color range" to JPEG. If you choose instead the preference "YUV color range" in MPEG, the white band is correctly at 100 IRE and the colored bands are 75 IRE, but... the black bands are now wrongly at 0 IRE... So no possibility to have a good reading. This is true whether I use the X11-OpenGL video driver or just X11. I got the same results (problems) using the color bar from the Grass Valley site: http://www.gvgdevelopers.com/K2DevGuide/Clips2/NTSC_SD_DV25_colorbar.avi http://www.gvgdevelopers.com/K2DevGuide/Clips2/NTSC_SD_DV50_colorbar.avi http://www.gvgdevelopers.com/K2DevGuide/Clips2/NTSC_SD_DVCAM_colorbar.avi Is the Waveform properly calibrated ? Pierre