Analogue formats (eg YUV, YCbCr, YV12, YUY2) have a full range of 0-255, but black is set to 16 and white to 235 (16-235 is often referred to as TV range). PC range sets black to 0 and white to 255. If you open a huffyuv compressed source avi in VirtualDub (which uses RGB), the Huffyuv codec will convert the video, because otherwise black will be too high (16) and white too low (235).
Analogue formats (eg YUV, YCbCr, YV12, YUY2) have a full range of 0-255, but black is set to 16 and white to 235 (16-235 is often referred to as TV range). PC range sets black to 0 and white to 255. If you open a huffyuv compressed source avi in VirtualDub (which uses RGB), the Huffyuv codec will convert the video, because otherwise black will be too high (16) and white too low (235).