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      1 /* ----------------------------------------------------------------
      2  *
      3  *
      4  * File Name:  omxVCM4P10_DequantTransformResidualFromPairAndAdd.c
      5  * OpenMAX DL: v1.0.2
      6  * Revision:   9641
      7  * Date:       Thursday, February 7, 2008
      8  *
      9  * (c) Copyright 2007-2008 ARM Limited. All Rights Reserved.
     10  *
     11  *
     12  *
     13  * H.264 inverse quantize and transform module
     14  *
     15  */
     16 
     17 #include "omxtypes.h"
     18 #include "armOMX.h"
     19 #include "omxVC.h"
     20 
     21 #include "armCOMM.h"
     22 #include "armVC.h"
     23 
     24 /*
     25  * Description:
     26  * Dequantize Luma AC block
     27  */
     28 
     29 static void DequantLumaAC4x4(
     30      OMX_S16* pSrcDst,
     31      OMX_INT QP
     32 )
     33 {
     34     const OMX_U8 *pVRow = &armVCM4P10_VMatrix[QP%6][0];
     35     int Shift = QP / 6;
     36     int i;
     37     OMX_S32 Value;
     38 
     39     for (i=0; i<16; i++)
     40     {
     41 
     42         Value = (pSrcDst[i] * pVRow[armVCM4P10_PosToVCol4x4[i]]) << Shift;
     43         pSrcDst[i] = (OMX_S16)Value;
     44     }
     45 }
     46 
     47 /**
     48  * Function:  omxVCM4P10_DequantTransformResidualFromPairAndAdd   (6.3.4.2.3)
     49  *
     50  * Description:
     51  * Reconstruct the 4x4 residual block from coefficient-position pair buffer,
     52  * perform dequantization and integer inverse transformation for 4x4 block of
     53  * residuals with previous intra prediction or motion compensation data, and
     54  * update the pair buffer pointer to next non-empty block. If pDC == NULL,
     55  * there re 16 non-zero AC coefficients at most in the packed buffer starting
     56  * from 4x4 block position 0; If pDC != NULL, there re 15 non-zero AC
     57  * coefficients at most in the packet buffer starting from 4x4 block position
     58  * 1.
     59  *
     60  * Input Arguments:
     61  *
     62  *   ppSrc - Double pointer to residual coefficient-position pair buffer
     63  *            output by CALVC decoding
     64  *   pPred - Pointer to the predicted 4x4 block; must be aligned on a 4-byte
     65  *            boundary
     66  *   predStep - Predicted frame step size in bytes; must be a multiple of 4
     67  *   dstStep - Destination frame step in bytes; must be a multiple of 4
     68  *   pDC - Pointer to the DC coefficient of this block, NULL if it doesn't
     69  *            exist
     70  *   QP - QP Quantization parameter.  It should be QpC in chroma 4x4 block
     71  *            decoding, otherwise it should be QpY.
     72  *   AC - Flag indicating if at least one non-zero AC coefficient exists
     73  *
     74  * Output Arguments:
     75  *
     76  *   pDst - pointer to the reconstructed 4x4 block data; must be aligned on a
     77  *            4-byte boundary
     78  *
     79  * Return Value:
     80  *    OMX_Sts_NoErr, if the function runs without error.
     81  *    OMX_Sts_BadArgErr - bad arguments: if one of the following cases occurs:
     82  *    -    pPred or pDst is NULL.
     83  *    -    pPred or pDst is not 4-byte aligned.
     84  *    -    predStep or dstStep is not a multiple of 4.
     85  *    -    AC !=0 and Qp is not in the range of [0-51] or ppSrc == NULL.
     86  *    -    AC ==0 && pDC ==NULL.
     87  *
     88  */
     89 
     90 OMXResult omxVCM4P10_DequantTransformResidualFromPairAndAdd(
     91      const OMX_U8 **ppSrc,
     92      const OMX_U8 *pPred,
     93      const OMX_S16 *pDC,
     94      OMX_U8 *pDst,
     95      OMX_INT predStep,
     96      OMX_INT dstStep,
     97      OMX_INT QP,
     98      OMX_INT AC
     99 )
    100 {
    101     OMX_S16 pBuffer[16+4];
    102     OMX_S16 *pDelta;
    103     int i,x,y;
    104 
    105     armRetArgErrIf(pPred == NULL,            OMX_Sts_BadArgErr);
    106     armRetArgErrIf(armNot4ByteAligned(pPred),OMX_Sts_BadArgErr);
    107     armRetArgErrIf(pDst   == NULL,           OMX_Sts_BadArgErr);
    108     armRetArgErrIf(armNot4ByteAligned(pDst), OMX_Sts_BadArgErr);
    109     armRetArgErrIf(predStep & 3,             OMX_Sts_BadArgErr);
    110     armRetArgErrIf(dstStep & 3,              OMX_Sts_BadArgErr);
    111     armRetArgErrIf(AC!=0 && (QP<0),          OMX_Sts_BadArgErr);
    112     armRetArgErrIf(AC!=0 && (QP>51),         OMX_Sts_BadArgErr);
    113     armRetArgErrIf(AC!=0 && ppSrc==NULL,     OMX_Sts_BadArgErr);
    114     armRetArgErrIf(AC!=0 && *ppSrc==NULL,    OMX_Sts_BadArgErr);
    115     armRetArgErrIf(AC==0 && pDC==NULL,       OMX_Sts_BadArgErr);
    116 
    117     pDelta = armAlignTo8Bytes(pBuffer);
    118 
    119     for (i=0; i<16; i++)
    120     {
    121         pDelta[i] = 0;
    122     }
    123     if (AC)
    124     {
    125         armVCM4P10_UnpackBlock4x4(ppSrc, pDelta);
    126         DequantLumaAC4x4(pDelta, QP);
    127     }
    128     if (pDC)
    129     {
    130         pDelta[0] = pDC[0];
    131     }
    132     armVCM4P10_TransformResidual4x4(pDelta,pDelta);
    133 
    134     for (y=0; y<4; y++)
    135     {
    136         for (x=0; x<4; x++)
    137         {
    138             pDst[y*dstStep+x] = (OMX_U8)armClip(0,255,pPred[y*predStep+x] + pDelta[4*y+x]);
    139         }
    140     }
    141 
    142     return OMX_Sts_NoErr;
    143 }
    144 
    145 /* End of file */
    146