Hi I have been looking at go's implementation YCbCr to RGB conversion and there are a few details that are not clear to me.
The implementation follows the JFIF spec // The JFIF specification says: // R = Y' + 1.40200*(Cr-128) // G = Y' - 0.34414*(Cb-128) - 0.71414*(Cr-128) // B = Y' + 1.77200*(Cb-128) // http://www.w3.org/Graphics/JPEG/jfif3.pdf says Y but means Y'. It seems that all constants above are multiplied by 2^16 to allow the calculation to be performed with integer arithmetic, before being shifted back into an 8 bit range. But Y' is multiplied by 0x010100 which is equivalent to Y' * 2^16 + Y' * 2^8. I can't see why Y' in this case is scaled differently to the other components of the equation. If anyone could shed some light, it would be greatly appreciated. Thanks Piers -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
