armicjp_dctquantinv_s16.c

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

/**
 * 
 * File Name:  armICJP_DCTQuantInv_S16.c
 * OpenMAX DL: v1.0.2
 * Revision:   10586
 * Date:       Wednesday, March 5, 2008
 * 
 * (c) Copyright 2007-2008 ARM Limited. All Rights Reserved.
 * 
 * 
 *
 * Description:
 * This file contains module for IDCT with de-quantization
 *
 */

#include "omxtypes.h"
#include "armOMX.h"
#include "omxIC.h"

#include "armIC.h"
#include "armCOMM.h"

/**
 * Function: armICJP_DCTQuantInv_S16
 *
 * Brief:
 * Single block dequantization and IDCT function.
 *
 * Description:
 * This function implements inverse DCT with (Optional) dequantization for 8-bit image data. It processes one
 * block (8x8).
 * The start address of pQuantRawTable and pQuantInvTable must be 8-byte aligned.
 *
 *
 * Parameters:
 * [in]  pSrc           identifies the input coefficient block (8x8) buffer. The start address must be 8-byte
 *                            aligned.
 * [in]  pQuantInvTable identifies the quantization table which was generated from
 *                            "omxICJP_DCTQuantInvTableInit". The table length is 64 entries by 32-bit wide. The start address must be
 *                            8-byte aligned. If this pointer is NULL dequantization is not performed
 *
 * [out] pDst           identifies output coefficient block(8x8) buffer. The start address must be 8-byte aligned.
 *
 * Return Value:
 * OMXVoid
 *
 */

OMXVoid armICJP_DCTQuantInv_S16(
     const OMX_S16 *pSrc,
     OMX_S16 *pDst,
     const OMX_U32 *pQuantInvTable
 )
{
    OMX_INT v,u,y,x,quantFlag;
    OMX_F64 coeff,mac,quant;
    
    if( pQuantInvTable == NULL )
    {
        quantFlag = 0;
    }
    else
    {
        quantFlag = 1;
    }
    
    /* Processing */
    for( y = 0 ; y < 8 ; y++)
    {
        for( x = 0 ; x < 8 ; x++)
        {
            /* Compute the IDCT coefficient */
            mac = 0.0;
            
            for( v = 0 ; v < 8 ; v++)
            {
                for( u = 0 ; u < 8 ; u++)
                {
                    /* Inverse Quantization */
                    if(quantFlag == 1)
                    {
                        coeff  = (OMX_F64)pSrc[v*8 + u];
                        quant = (OMX_F64)pQuantInvTable[v*8 + u];
                        coeff  *= quant;
                    }
                    else
                    {
                        coeff  = (OMX_F64)pSrc[v*8 + u];
                    }
                    
                    coeff *= (armICJP_CosTable[x][u] *
                                armICJP_CosTable[y][v]);
                    
                    mac  += coeff;
                }
            }
            
            /*Store the result*/
            pDst[y*8 + x] = armSatRoundFloatToS16(mac);
        }
    }
}

/*End of File*/