Auto merge of #3148 - jyavenard:Color16, r=kvark
Auto merge of #3148 - jyavenard:Color16, r=kvark

Add 16 bits YUV support

Windows use 10 bits content as described in https://docs.microsoft.com/en-us/windows/desktop/medfound/10-bit-and-16-bit-yuv-video-formats
stored on 16 bits DWORD with the lowest 6 bits set to zero.

This is done so that 10, 12, 16 can all be cast to a 16 bits value, with no scaling.

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