YCbCr420ToRGB565Dither, YCbCr420ToRGB555Dither, YCbCr420ToRGB444Dither

Convert a YCbCr image that has 4:2:0 sampling format to the 16-bit per pixel RGB image with dithering.

Syntax

IppStatus ippiYCbCr420ToRGB565Dither_8u16u_P3C3R(const Ipp8u* pSrc[3], int srcStep[3], Ipp16u* pDst, int dstStep, IppiSize roiSize);

IppStatus ippiYCbCr420ToRGB555Dither_8u16u_P3C3R(const Ipp8u* pSrc[3], int srcStep[3], Ipp16u* pDst, int dstStep, IppiSize roiSize);

IppStatus ippiYCbCr420ToRGB444Dither_8u16u_P3C3R(const Ipp8u* pSrc[3], int srcStep[3], Ipp16u* pDst, int dstStep, IppiSize roiSize);

Parameters

pSrc	An array of pointers to ROI in separate planes of the source image.
srcStep	An array of distances in bytes between starts of consecutive lines in the source image planes.
pDst	Pointer to the destination image ROI.
dstStep	Distance in bytes between starts of consecutive lines in the destination image.
roiSize	Size of the source and destination ROI in pixels.

Description

The functions ippiYCbCr420ToRGB565Dither, ippiYCbCr420ToRGB555Dither, ippiYCbCr420ToRGB444Dither are declared in the ippcc.h file. They operate with ROI (see Regions of Interest in Intel IPP).

These functions convert the Y'Cb'Cr' image pSrc, packed in the 4:2:0 sampling format (see Table “Pixel-Order Image Formats” for more details), to the gamma-corrected R'G'B' image pDst according to the same formulas as the function ippiYCbCrToRGB does.

The destination image pDst is a packed 16-bit RGB image with reduced bit depth; all 3 channel intensities for a pixel are packed into two consecutive bytes (16u data type). It can be in one of three possible formats (see Figure 16-bit Pixel Formats for more details): RGB565 (5 bits for red, 6 bits for green, 5 bits for blue), RGB555 (5 bits for red, green, blue), or RGB444 (4 bits for red, green, blue).

Bit reduction is performed using the Bayer's threshold dithering algorithm with a 4x4 matrix [Tho91].

Return Values

ippStsNoErr	Indicates no error. Any other value indicates an error or a warning.
ippStsNullPtrErr	Indicates an error condition if pSrc or pDst is NULL.
ippStsSizeErr	Indicates an error condition if roiSize has a field with a zero or negative value.