Basically, YUV is an analog format for PAL TV signals, like YIQ for NTCS, and is not used within computer graphics.
Computers use YCbCr, which is basically the same thing. However, the conversion factors depend on the codec. HDTV signals (H.264) and SDTV signals (MPEG-2) uses different croma factors in the YCbCr conversion.
So what you are looking for is not a definitive answer between YUV and YCbCr, but rather which factors to use in your YCbCr conversion, which in turn depends on the codec you are en/decoding for.