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The functionippiCFAToRGB is declared in the ippcc.h file. It operates with ROI (see Regions of Interest in Intel IPP). This function transforms the 1-channel gray-scale image pSrc that is produced by applying the color filter array (CFA) - array of Bayer filters, to 24-bit 3-channel RGB image. Each element of the source image contains intensity value for only one color component, two others are interpolated using neighbor elements. Four variants of the order of the color component in the source image (Bayer grid) are allowed (see Figure 6-19) that is specified by the enumerator IppiBayerGrid.