CMYKToYCCK444LS_MCU

Convert CMYK data block to 4:4:4 YCCK MCU

Synopsis

FwStatus   fwiCMYKToYCCK444LS_MCU_8u16s_C4P4R ( const Fw8u * pSrcCMYKint srcStepFw16s * pDstMCU[4] );

Parameters

pDstMCU[4]   Array of pointers to destination MCU image blocks.
pSrcCMYK   Pointer to source image ROI for CMYK image format.
srcStep   Source buffer step size (width of the buffer in bytes).

Description

This function steps through an 8X8 data block in a source buffer, converts the source data from the CMYK color model to the YCCK color space with 4:4:4 chroma sub-sampling, level-shifts the unsigned values to signed values, creates a minimum coded unit, and writes the data to a destination buffer.

The following formulas are used to convert cyan, magenta, and yellow values to red, green, and blue values.

 R = 255 -C
 G = 255 -M
 B = 255 -Y

The following formulas are used to convert red, green, and blue values to luminance and chrominance values.

 Y = 0.299*R + 0.587*G + 0.114*B
 Cb = -0.16874*R - 0.33126*G + 0.5*B + 128
 Cr = 0.5*R - 0.41869*G - 0.08131*B + 128

The black (K) channel value remains the same during conversion.