omxipcs_ycbycr422tobgr888_u8_c2c3r.c

The OpenMAX DL (Development Layer) APIs contain a comprehensive set of audio, video, signal processi

/**
 *
 * 
 * File Name:  omxIPCS_YCbYCr422ToBGR888_U8_C2C3R.c
 * OpenMAX DL: v1.0.2
 * Revision:   10586
 * Date:       Wednesday, March 5, 2008
 * 
 * (c) Copyright 2007-2008 ARM Limited. All Rights Reserved.
 * 
 * 
 *
 * Description  : Colour Conversion Routine - YUV422 to BGR888 in floating point.
 *                The source is in two-channel format and pixel domain, and
 *                the destination in three-channel format and pixel domain.
 *
 */

#include "omxtypes.h"
#include "armOMX.h"
#include "omxIP.h"
#include "armCOMM.h"
#include "armIP.h"


/**
 * Function:  omxIPCS_YCbYCr422ToBGR888_U8_C2C3R   (4.4.3.1.6)
 *
 * Description:
 * Convert a pixel-oriented YCbYCr422 input image to a pixel-oriented BGR888 
 * or BGR565 output image.  The ROI of the source image is pointed to by pSrc, 
 * and the result is placed into the ROI of the destination image referenced 
 * by pDst. Memory organization for pixel-oriented YCbYCr422, BGR888, and 
 * BGR565 images is specified in Table 4-1. 
 *
 * Input Arguments:
 *   
 *   pSrc - pointer to the source ROI 
 *   srcStep - distance in bytes between the starts of consecutive lines in 
 *            the source image 
 *   dstStep - distance in bytes between the starts of consecutive lines in 
 *            the destination image 
 *   roiSize - size of the source and destination ROI in pixels 
 *
 * Output Arguments:
 *   
 *   pDst - pointer to the destination ROI 
 *
 * Return Value:
 *    
 *    OMX_Sts_NoErr - no error 
 *    OMX_Sts_BadArgErr - bad arguments detected; at least one of the 
 *              following is true: 
 *    -    pSrc or pDst is NULL 
 *    -    srcStep or dstStep is less than or equal to zero 
 *    -    srcStep/2 < roiSize.width 
 *    -    omxIPCS_YCbYCr422ToBGR888_U8_C2C3R() only: dstStep/3 < roiSize.width 
 *    -    omxIPCS_YCbYCr422ToBGR565_U8_U16_C2C3R() only: dstStep/2 < roiSize.width 
 *    -    roiSize has a field with zero or negative value 
 *
 */
 
OMXResult omxIPCS_YCbYCr422ToBGR888_U8_C2C3R(
        const OMX_U8 *pSrc,
        OMX_INT srcStep,
        OMX_U8 *pDst,
        OMX_INT dstStep,
        OMXSize roiSize
       )
{
    OMX_INT convWidth   = roiSize.width;  /* convWidth is the bytes to read */
    OMX_INT convHeight  = roiSize.height;
    OMX_U8  Y0data, Y1data, Udata, Vdata;
    OMX_INT i, j, k;
    
    armRetArgErrIf(!pSrc, OMX_Sts_BadArgErr);
    armRetArgErrIf(!pDst, OMX_Sts_BadArgErr);
    armRetArgErrIf(srcStep <= 0, OMX_Sts_BadArgErr);
    armRetArgErrIf(dstStep <= 0, OMX_Sts_BadArgErr);
    armRetArgErrIf(roiSize.width <= 0, OMX_Sts_BadArgErr);
    armRetArgErrIf(roiSize.height <= 0, OMX_Sts_BadArgErr);
    
    armRetArgErrIf(srcStep/2 < roiSize.width, OMX_Sts_BadArgErr);
    armRetArgErrIf(dstStep/3 < roiSize.width, OMX_Sts_BadArgErr);
    /*
    ------------------------------------------------------------------------
    Colour conversion equations
    R = 1.164(Y-16) + 1.596(Cr-128)
    G = 1.164(Y-16) - 0.813(Cr-128) - 0.392(Cb-128)
    B = 1.164(Y-16) + 2.017(Cb-128)
    
   
    INTERLEAVED YUV422 DATA (Current input format) |YU|YV|YU|YV|...
    
    The armIPCS_ComputeXFromYUV_Raw() functions apart from doing the colour 
    conversion, takes care of type-conversion from intermediate float values
    and clipping to U8, taking care of rounding errors.
    ------------------------------------------------------------------------
    */
   
    for(i=0; i<convHeight; i++, pSrc+=srcStep, pDst+=dstStep)
    {
        j=0;
        k=0;
        convWidth   = roiSize.width;
        while(convWidth >= 2)
        {
            Y0data      = pSrc[j];
            Udata       = pSrc[j+1];
            Y1data      = pSrc[j+2];
            Vdata       = pSrc[j+3];

            armIPCS_ComputeRGBFromYUV_F32_U8(Y0data, Udata, Vdata, &pDst[k+2], &pDst[k+1], &pDst[k]);
            armIPCS_ComputeRGBFromYUV_F32_U8(Y1data, Udata, Vdata, &pDst[k+5], &pDst[k+4], &pDst[k+3]);
            j+=4; 
            k+=6;
            convWidth -= 2;
        }
        if(convWidth == 1)
        {
            Y0data      = pSrc[j];
            Udata       = pSrc[j+1];
            Vdata       = pSrc[j+3];
            armIPCS_ComputeRGBFromYUV_F32_U8(Y0data, Udata, Vdata, &pDst[k+2], &pDst[k+1], &pDst[k]);
        }
    }
    return OMX_Sts_NoErr;
}

/* End of file */