opencv rgb转YUV公式

RGB ↔ YCrCb JPEG (or YCC)

Y \leftarrow 0.299 \cdot R + 0.587 \cdot G + 0.114 \cdot B

C r \leftarrow (R - Y) \cdot 0.713 + d e l t a

C b \leftarrow (B - Y) \cdot 0.564 + d e l t a

R \leftarrow Y + 1.403 \cdot (C r - d e l t a)

G \leftarrow Y - 0.714 \cdot (C r - d e l t a) - 0.344 \cdot (C b - d e l t a)

B \leftarrow Y + 1.773 \cdot (C b - d e l t a)

where

d e l t a = ⎧⎩⎨⎪⎪ 128 32768 0.5 for 8-bit images for 16-bit images for floating-point images

Y, Cr, and Cb cover the whole value range.