YPbPr和YCbCr正解

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Usage of the terms YUV, YPbPr, YCbCr
The broadcast and electronics industrieshave not been very precise in the use of the component interfaceterminology. Many people use the term "YUV" to mean YPbPr or YCbCr andseveral other standardized color component interfaces like YIQ, andYCC. Unfortunately, even many textbooks have confused usage of theseterms. "YUV" is just easier to say and remember than YPbPr or YCbCr.
To avoid confusion Techwell marketingstandardized the usage of the terminology in our datasheets. YPbPr isused when discussing the three-wire analog video component interfaceEIA-770. The terminology YCbCr is used when discussing ITU-601 orITU-656 digital interfaces.
YPbPr = analog component interface color space, (EIA-770.2-a SMPTE-240M and others)
YCbCr = digital component interface, (ITU-601, ITU-656, (formerly CCIR-601, CCIR-656))
YPbPr and YCbCr are not different colorspaces. They where intended to be the analog and digitalrepresentations of the same color space. ITU 601 (formerly calledCCIR-601) defines an 8-bit DIGITAL 2'scompliment coding for componentvideo called YCbCr. The offsets and some scale factors specified in thedefinition are integer numbers with exact 8-bit binary equivalents. Theoffsets and scaling factors are specified to prevent digital overflowsof the 8-bit integer numbers. YCbCr is used when describing our 601 and656 DIGITAL interfaces. Other datasheets may use YUV, YPbPr or otherlabels for the same interface.
CCIR Rec. 709 and EIA-770.2-A defines theYPbPr analog interface for HDTV. Most HDTV and DVD consumer electronicsequipment now use terminology "YPbPr" for the 3-wire analog videointerconnect. The offsets and scaling factors are specified to preventsaturation of the amplifiers of the analog signals. These are theanalog interfaces that the TW99 and TW88 is intended to interface with.Other datasheets may use YUV, YCbCr, or other labels for the sameinterface.
Technically “YUV” applies to the correctscaling of the color difference signals when they are to be modulatedand output as a composite (one pin) video signal. At this time it israre to see an analog three-wire interface with color differencesignals scaled to the YUV convention available on outside of anintegrated circuit. However the colloquial use the term “YUV” persistsalong with the confusion between YCbCr and YPbPr. The order of theterms YCbCr and YPbPr are also “normally” reversed to YCrCb and YPrPbas any quick search on the Internet will reveal.

雷克

好，很好，非常好！