BGRToYCbCr411LS

Converts an BGR image to the YCbCr color model and creates 411 MCU.

Syntax

IppStatus ippiBGRToYCbCr411LS_MCU_8u16s_C3P3R(const Ipp8u* pSrcBGR, int srcStep, Ipp16s* pDstMCU[3]);

Parameters

pSrcBGR	Pointer to the source image ROI.
srcStep	Distance in bytes between starts of consecutive lines in the source image.
pDstMCU	Array of 3 pointers to the destination image blocks.

Description

The function ippiBGRToYCbCr411LS_MCU is declared in the ippj.h file. It operates with ROI (see Regions of Interest in Intel IPP).

This function converts an BGR image to the YCbCr image using the same formulas as the ippiRGBToYCbCr_JPEG function for computing Y, Cb, and Cr component values.

Additionally, this function converts source data from unsigned Ipp8u range [0..255] to the signed Ipp16s range [-128..127] performing level shift operation (by subtracting 128) and creates 411 MCU (see Figure “MCU Structure for Different JPEG Sampling Formats”).

Downsampling is performed by plain averaging.

Return Values

ippStsNoErr	Indicates no error.
ippStsNullPtrErr	Indicates an error condition if any of the specified pointers is NULL.
ippStsStepErr	Indicates an error condition if srcStep has a zero or negative value.