/*

* Copyright (c) 2010 Ixonos Plc.

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of the "Eclipse Public License v1.0"

* which accompanies this distribution, and is available

* at the URL "http://www.eclipse.org/legal/epl-v10.html".

*

* Initial Contributors:

* Nokia Corporation - Initial contribution

*

* Contributors:

* Ixonos Plc

*

* Description:  

* Block decoding functions.

*

*/

#include "h263dConfig.h"

#include "decblock.h"

#include "blkfunc.h"

#include "viddemux.h"

#include "idct.h"   

/* {{-output"dblfree.txt"}} */

/*

 * dblFree

 *    

 *

 * Parameters:

 *    None.

 *

 * Function:

 *    This function deinitializes the module.

 *    Any functions of this module must not be called after dblFree (except 

 *    for dblLoad).

 *

 * Returns:

 *    >= 0  if succeeded

 *    < 0   if failed

 *

 */

int dblFree(void)

/* {{-output"dblfree.txt"}} */

{

   return 0;

}

/* {{-output"dblload.txt"}} */

/*

 * dblLoad

 *    

 *

 * Parameters:

 *    None.

 *

 * Function:

 *    This function initializes the module.

 *    dblLoad has to be called before any other function of this module

 *    is used.

 *

 * Returns:

 *    >= 0  if succeeded

 *    < 0   if failed

 *

 */

int dblLoad(void)

/* {{-output"dblload.txt"}} */

{    

   return 0;

}

/* {{-output"dblIdctAndDequant.txt"}} */

/*

 * dblIdctAndDequant

 *

 * Parameters:

 *    block          block array (length 64)

 *    quant          quantization information

 *    skip           must be 1 if INTRADC is in the block, otherwise 0

 *

 * Function:

 *    This function makes the dequantization, the clipping and the inverse

 *    cosine transform for the given block.

 *

 * Returns:

 *    Nothing.

 *

 * Error codes:

 *    None.

 *

 */

void dblIdctAndDequant(int *block, int quant, int skip)

/* {{-output"dblIdctAndDequant.txt"}} */

{

   int rec, i, *tmpBlock, level;

   /* See section 6.2.1 of H.263 Recommendation for Inverse Quantization

      formulas. */

   /* If odd quantization parameter */

   if (quant & 1) {

      for (i = 64 - skip, tmpBlock = block + skip; i; i--, tmpBlock++) {

         if (!(*tmpBlock))

            continue;

         level = *tmpBlock;

         if (level > 0) {

            rec = quant * ((level << 1) + 1);

            *tmpBlock = (rec < 2048) ? rec : 2047;

         }

         else {

            rec = -(quant * (((-level) << 1) + 1));

            *tmpBlock = (rec < -2048) ? -2048 : rec;

         }

      }

   }

   /* Else even quantization parameter */

   else {

      /* For loop copy-pasted from the previous case due to speed 

         optimization */

      for (i = 64 - skip, tmpBlock = block + skip; i; i--, tmpBlock++) {

         if (!(*tmpBlock))

            continue;

         level = *tmpBlock;

         if (level > 0) {

            rec = quant * ((level << 1) + 1) - 1;

            *tmpBlock = (rec < 2048) ? rec : 2047;

         }

         else {

            rec = -(quant * (((-level) << 1) + 1) - 1);

            *tmpBlock = (rec < -2048) ? -2048 : rec;

         }

      }

   }

   idct(block);

}

/*

 * dblIdct

 *

 * Parameters:

 *    block          block array (length 64)

 *

 * Function:

 *    This function makes the inverse

 *    cosine transform for the given block.

 *

 * Returns:

 *    Nothing.

 *

 * Error codes:

 *    None.

 *

 */

void dblIdct(int *block)

{

   idct(block);

}

// End of File