/******************************************************************************
*
* Copyright (C) 2015 The Android Open Source Project
*
* 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.
*
*****************************************************************************
* Originally developed and contributed by Ittiam Systems Pvt. Ltd, Bangalore
*/
/**
*******************************************************************************
* @file
* ih264e_half_pel.c
*
* @brief
* This file contains functions that are used for computing subpixel planes
*
* @author
* ittiam
*
* @par List of Functions:
* - ih264e_sixtapfilter_horz
* - ih264e_sixtap_filter_2dvh_vert
*
* @remarks
* None
*
*******************************************************************************
*/
/*****************************************************************************/
/* File Includes */
/*****************************************************************************/
/* System include files */
#include <stdio.h>
#include <assert.h>
#include <limits.h>
/* User include files */
#include "ih264_typedefs.h"
#include "ithread.h"
#include "ih264_platform_macros.h"
#include "ih264_defs.h"
#include "ih264e_half_pel.h"
#include "ih264_macros.h"
#include "ih264e_debug.h"
#include "ih264_inter_pred_filters.h"
#include "ih264_mem_fns.h"
#include "ih264_padding.h"
#include "ih264_intra_pred_filters.h"
#include "ih264_deblk_edge_filters.h"
/*****************************************************************************/
/* Function Definitions */
/*****************************************************************************/
/**
*******************************************************************************
*
* @brief
* Interprediction luma filter for horizontal input (Filter run for width = 17
* and height =16)
*
* @par Description:
* Applies a 6 tap horizontal filter .The output is clipped to 8 bits
* sec 8.4.2.2.1 titled "Luma sample interpolation process"
*
* @param[in] pu1_src
* UWORD8 pointer to the source
*
* @param[out] pu1_dst
* UWORD8 pointer to the destination
*
* @param[in] src_strd
* integer source stride
*
* @param[in] dst_strd
* integer destination stride
*
* @returns
*
* @remarks
* None
*
*******************************************************************************
*/
void ih264e_sixtapfilter_horz(UWORD8 *pu1_src,
UWORD8 *pu1_dst,
WORD32 src_strd,
WORD32 dst_strd)
{
UWORD32 u4_i, u4_j;
UWORD32 u4_w, u4_h;
/* width and height of interpolation */
u4_w = HP_PL_WD;
u4_h = MB_SIZE;
pu1_src -= 2;
for (u4_i = 0; u4_i < u4_h; u4_i++)
{
for (u4_j = 0; u4_j < u4_w; u4_j++, pu1_dst++, pu1_src++)
{
WORD16 i16_temp;
i16_temp = ih264_g_six_tap[0] * (*pu1_src + pu1_src[5])
+ ih264_g_six_tap[1] * (pu1_src[1] + pu1_src[4])
+ ih264_g_six_tap[2] * (pu1_src[2] + pu1_src[3]);
i16_temp = (i16_temp + 16) >> 5;
*pu1_dst = CLIP_U8(i16_temp);
}
pu1_src += src_strd - u4_w;
pu1_dst += dst_strd - u4_w;
}
}
/**
*******************************************************************************
*
* @brief
* This function implements a two stage cascaded six tap filter. It applies
* the six tap filter in the vertical direction on the predictor values,
* followed by applying the same filter in the horizontal direction on the
* output of the first stage. The six tap filtering operation is described in
* sec 8.4.2.2.1 titled "Luma sample interpolation process" (Filter run for
* width = 17 and height = 17)
*
* @par Description:
* The function interpolates the predictors first in the vertical direction and
* then in the horizontal direction to output the (1/2,1/2). The output of the
* first stage of the filter is stored in the buffer pointed to by
* pi16_pred1(only in C) in 16 bit precision.
*
* @param[in] pu1_src
* UWORD8 pointer to the source
*
* @param[out] pu1_dst1
* UWORD8 pointer to the destination (Horizontal filtered output)
*
* @param[out] pu1_dst2
* UWORD8 pointer to the destination (output after applying vertical filter to
* the intermediate horizontal output)
*
* @param[in] src_strd
* integer source stride
* @param[in] dst_strd
* integer destination stride of pu1_dst
*
* @param[in] pi4_pred
* Pointer to 16bit intermediate buffer (used only in c)
*
* @param[in] i4_pred_strd
* integer destination stride of pi16_pred1
*
* @returns
*
* @remarks
* None
*
*******************************************************************************
*/
void ih264e_sixtap_filter_2dvh_vert(UWORD8 *pu1_src,
UWORD8 *pu1_dst1,
UWORD8 *pu1_dst2,
WORD32 src_strd,
WORD32 dst_strd,
WORD32 *pi4_pred,
WORD32 i4_pred_strd)
{
WORD32 row, col;
WORD32 tmp;
WORD32 *pi4_pred_temp = pi4_pred;
WORD32 ht = HP_PL_HT, wd = HP_PL_WD;
for (row = 0; row < ht; row++)
{
for (col = -2; col < wd + 3; col++)
{
tmp = ih264_g_six_tap[0] * (pu1_src[col - 2 * src_strd] + pu1_src[col + 3 * src_strd]) +
ih264_g_six_tap[1] * (pu1_src[col - 1 * src_strd] + pu1_src[col + 2 * src_strd]) +
ih264_g_six_tap[2] * (pu1_src[col] + pu1_src[col + 1 * src_strd]);
pi4_pred_temp[col] = tmp;
}
pu1_src += src_strd;
pi4_pred_temp += i4_pred_strd;
}
for (row = 0; row < ht; row++)
{
for (col = 0; col < wd; col++)
{
tmp = (pi4_pred[col - 2] + pi4_pred[col + 3]) +
ih264_g_six_tap[1] * (pi4_pred[col - 1] + pi4_pred[col + 2]) +
ih264_g_six_tap[2] * (pi4_pred[col] + pi4_pred[col + 1]);
tmp = (tmp + 512) >> 10;
pu1_dst2[col] = CLIP_U8(tmp);
pu1_dst1[col] = CLIP_U8((pi4_pred[col] + 16) >> 5);
}
pi4_pred += i4_pred_strd;
pu1_dst2 += dst_strd;
pu1_dst1 += dst_strd;
}
}