/******************************************************************************
*
* Copyright (C) 2012 Ittiam Systems Pvt Ltd, Bangalore
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
******************************************************************************/
/**
*******************************************************************************
* @file
* ihevc_chroma_itrans_recon.c
*
* @brief
* Contains function definitions for inverse transform and reconstruction
* of chroma interleaved data.
*
* @author
* 100470
*
* @par List of Functions:
* - ihevc_chroma_itrans_recon_4x4()
*
* @remarks
* None
*
*******************************************************************************
*/
#include <stdio.h>
#include <string.h>
#include "ihevc_typedefs.h"
#include "ihevc_macros.h"
#include "ihevc_platform_macros.h"
#include "ihevc_defs.h"
#include "ihevc_trans_tables.h"
#include "ihevc_chroma_itrans_recon.h"
#include "ihevc_func_selector.h"
#include "ihevc_trans_macros.h"
/* All the functions work one component(U or V) of interleaved data depending upon pointers passed to it */
/* Data visualization */
/* U V U V U V U V */
/* U V U V U V U V */
/* U V U V U V U V */
/* U V U V U V U V */
/* If the pointer points to first byte of above stream (U) , functions will operate on U component */
/* If the pointer points to second byte of above stream (V) , functions will operate on V component */
/**
*******************************************************************************
*
* @brief
* This function performs Inverse transform and reconstruction for 4x4
* input block
*
* @par Description:
* Performs inverse transform and adds the prediction data and clips output
* to 8 bit
*
* @param[in] pi2_src
* Input 4x4 coefficients
*
* @param[in] pi2_tmp
* Temporary 4x4 buffer for storing inverse transform
* 1st stage output
*
* @param[in] pu1_pred
* Prediction 4x4 block
*
* @param[out] pu1_dst
* Output 4x4 block
*
* @param[in] src_strd
* Input stride
*
* @param[in] pred_strd
* Prediction stride
*
* @param[in] dst_strd
* Output Stride
*
* @param[in] shift
* Output shift
*
* @param[in] zero_cols
* Zero columns in pi2_src
*
* @returns Void
*
* @remarks
* None
*
*******************************************************************************
*/
void ihevc_chroma_itrans_recon_4x4(WORD16 *pi2_src,
WORD16 *pi2_tmp,
UWORD8 *pu1_pred,
UWORD8 *pu1_dst,
WORD32 src_strd,
WORD32 pred_strd,
WORD32 dst_strd,
WORD32 zero_cols,
WORD32 zero_rows)
{
WORD32 j;
WORD32 e[2], o[2];
WORD32 add;
WORD32 shift;
WORD16 *pi2_tmp_orig;
WORD32 trans_size;
UNUSED(zero_rows);
trans_size = TRANS_SIZE_4;
pi2_tmp_orig = pi2_tmp;
/* Inverse Transform 1st stage */
shift = IT_SHIFT_STAGE_1;
add = 1 << (shift - 1);
for(j = 0; j < trans_size; j++)
{
/* Checking for Zero Cols */
if((zero_cols & 1) == 1)
{
memset(pi2_tmp, 0, trans_size * sizeof(WORD16));
}
else
{
/* Utilizing symmetry properties to the maximum to minimize the number of multiplications */
o[0] = g_ai2_ihevc_trans_4[1][0] * pi2_src[src_strd]
+ g_ai2_ihevc_trans_4[3][0] * pi2_src[3 * src_strd];
o[1] = g_ai2_ihevc_trans_4[1][1] * pi2_src[src_strd]
+ g_ai2_ihevc_trans_4[3][1] * pi2_src[3 * src_strd];
e[0] = g_ai2_ihevc_trans_4[0][0] * pi2_src[0]
+ g_ai2_ihevc_trans_4[2][0] * pi2_src[2 * src_strd];
e[1] = g_ai2_ihevc_trans_4[0][1] * pi2_src[0]
+ g_ai2_ihevc_trans_4[2][1] * pi2_src[2 * src_strd];
pi2_tmp[0] =
CLIP_S16(((e[0] + o[0] + add) >> shift));
pi2_tmp[1] =
CLIP_S16(((e[1] + o[1] + add) >> shift));
pi2_tmp[2] =
CLIP_S16(((e[1] - o[1] + add) >> shift));
pi2_tmp[3] =
CLIP_S16(((e[0] - o[0] + add) >> shift));
}
pi2_src++;
pi2_tmp += trans_size;
zero_cols = zero_cols >> 1;
}
pi2_tmp = pi2_tmp_orig;
/* Inverse Transform 2nd stage */
shift = IT_SHIFT_STAGE_2;
add = 1 << (shift - 1);
for(j = 0; j < trans_size; j++)
{
WORD32 itrans_out;
/* Utilizing symmetry properties to the maximum to minimize the number of multiplications */
o[0] = g_ai2_ihevc_trans_4[1][0] * pi2_tmp[trans_size]
+ g_ai2_ihevc_trans_4[3][0] * pi2_tmp[3 * trans_size];
o[1] = g_ai2_ihevc_trans_4[1][1] * pi2_tmp[trans_size]
+ g_ai2_ihevc_trans_4[3][1] * pi2_tmp[3 * trans_size];
e[0] = g_ai2_ihevc_trans_4[0][0] * pi2_tmp[0]
+ g_ai2_ihevc_trans_4[2][0] * pi2_tmp[2 * trans_size];
e[1] = g_ai2_ihevc_trans_4[0][1] * pi2_tmp[0]
+ g_ai2_ihevc_trans_4[2][1] * pi2_tmp[2 * trans_size];
itrans_out =
CLIP_S16(((e[0] + o[0] + add) >> shift));
pu1_dst[0 * 2] = CLIP_U8((itrans_out + pu1_pred[0 * 2]));
itrans_out =
CLIP_S16(((e[1] + o[1] + add) >> shift));
pu1_dst[1 * 2] = CLIP_U8((itrans_out + pu1_pred[1 * 2]));
itrans_out =
CLIP_S16(((e[1] - o[1] + add) >> shift));
pu1_dst[2 * 2] = CLIP_U8((itrans_out + pu1_pred[2 * 2]));
itrans_out =
CLIP_S16(((e[0] - o[0] + add) >> shift));
pu1_dst[3 * 2] = CLIP_U8((itrans_out + pu1_pred[3 * 2]));
pi2_tmp++;
pu1_pred += pred_strd;
pu1_dst += dst_strd;
}
}