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      1 /**
      2  *
      3  * File Name:  omxVCM4P10_InvTransformDequant_ChromaDC.c
      4  * OpenMAX DL: v1.0.2
      5  * Revision:   9641
      6  * Date:       Thursday, February 7, 2008
      7  *
      8  * (c) Copyright 2007-2008 ARM Limited. All Rights Reserved.
      9  *
     10  *
     11  * Description:
     12  * This function will calculate 4x4 hadamard transform of chroma DC
     13  * coefficients and quantization
     14  *
     15  */
     16 
     17 #include "omxtypes.h"
     18 #include "armOMX.h"
     19 #include "omxVC.h"
     20 
     21 #include "armVC.h"
     22 #include "armCOMM.h"
     23 
     24 /**
     25  * Function:  omxVCM4P10_InvTransformDequant_ChromaDC   (6.3.5.6.4)
     26  *
     27  * Description:
     28  * This function performs inverse 2x2 Hadamard transform and then dequantizes
     29  * the coefficients.
     30  *
     31  * Input Arguments:
     32  *
     33  *   pSrc - Pointer to the 2x2 array of the 2x2 Hadamard-transformed and
     34  *            quantized coefficients.  8 byte alignment required.
     35  *   iQP - Quantization parameter; must be in the range [0,51].
     36  *
     37  * Output Arguments:
     38  *
     39  *   pDst - Pointer to inverse-transformed and dequantized coefficients.
     40  *            8-byte alignment required.
     41  *
     42  * Return Value:
     43  *
     44  *    OMX_Sts_NoErr - no error
     45  *    OMX_Sts_BadArgErr - bad arguments; returned if any of the following
     46  *              conditions are true:
     47  *    -    at least one of the following pointers is NULL: pSrc
     48  *    -    pSrc or pDst is not aligned on an 8-byte boundary
     49  *
     50  */
     51 OMXResult omxVCM4P10_InvTransformDequant_ChromaDC(
     52 	const OMX_S16* 	pSrc,
     53 	OMX_S16*	pDst,
     54 	OMX_U32		iQP
     55 )
     56 {
     57     OMX_INT     i, j;
     58     OMX_S32     m[2][2];
     59     OMX_S32     QPer, V00, Value;
     60 
     61     /* check for argument error */
     62     armRetArgErrIf(pSrc == NULL, OMX_Sts_BadArgErr)
     63     armRetArgErrIf(armNot8ByteAligned(pSrc), OMX_Sts_BadArgErr);
     64     armRetArgErrIf(pDst == NULL, OMX_Sts_BadArgErr)
     65     armRetArgErrIf(armNot8ByteAligned(pDst), OMX_Sts_BadArgErr);
     66     armRetArgErrIf(iQP > 51, OMX_Sts_BadArgErr)
     67 
     68     /* Inv Hadamard Transform for 2x2 block */
     69     m[0][0] = pSrc[0] + pSrc[1] +  pSrc[2] + pSrc[3];
     70     m[0][1] = pSrc[0] - pSrc[1] +  pSrc[2] - pSrc[3];
     71     m[1][0] = pSrc[0] + pSrc[1] -  pSrc[2] - pSrc[3];
     72     m[1][1] = pSrc[0] - pSrc[1] -  pSrc[2] + pSrc[3];
     73 
     74     /* Quantization */
     75     /* Scaling */
     76     QPer = iQP / 6;
     77     V00 = armVCM4P10_VMatrix [iQP % 6][0];
     78 
     79     for (j = 0; j < 2; j++)
     80     {
     81         for (i = 0; i < 2; i++)
     82         {
     83             if (QPer < 1)
     84             {
     85                 Value = (m[j][i] * V00) >> 1;
     86             }
     87             else
     88             {
     89                 Value = (m[j][i] * V00) << (QPer - 1);
     90             }
     91 
     92             pDst[j * 2 + i] = (OMX_S16) Value;
     93         }
     94     }
     95 
     96     return OMX_Sts_NoErr;
     97 }
     98 
     99 /*****************************************************************************
    100  *                              END OF FILE
    101  *****************************************************************************/
    102 
    103