armVCM4P10_InterpolateHalfVer_Luma.c revision 78e52bfac041d71ce53b5b13c2abf78af742b09d 
1/*
2 * Copyright (C) 2007-2008 ARM Limited
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 *
16 */
17/**
18 *
19 * File Name:  armVCM4P10_InterpolateHalfVer_Luma.c
20 * OpenMAX DL: v1.0.2
21 * Revision:   9641
22 * Date:       Thursday, February 7, 2008
23 *
24 *
25 *
26 * Description:
27 * This functions will help to calculate Half Pel luma interpolation
28 *
29 */
30
31#include "omxtypes.h"
32#include "armOMX.h"
33#include "omxVC.h"
34
35#include "armCOMM.h"
36#include "armVC.h"
37
38/**
39 * Function: armVCM4P10_InterpolateHalfVer_Luma
40 *
41 * Description:
42 * This function performs interpolation for vertical 1/2-pel positions
43 * around a full-pel position.
44 *
45 * Remarks:
46 *
47 *  [in]    pSrc        Pointer to top-left corner of block used to interpolate
48 *                      in the reconstructed frame plane
49 *  [in]    iSrcStep    Step of the source buffer.
50 *  [in]    iDstStep    Step of the destination(interpolation) buffer.
51 *  [in]    iWidth      Width of the current block
52 *  [in]    iHeight     Height of the current block
53 *  [out]   pDst        Pointer to the interpolation buffer of the 1/2-pel
54 *
55 * Return Value:
56 * Standard OMXResult value.
57 *
58 */
59
60OMXResult armVCM4P10_InterpolateHalfVer_Luma(
61     const OMX_U8*    pSrc,
62     OMX_U32    iSrcStep,
63     OMX_U8*    pDst,
64     OMX_U32    iDstStep,
65     OMX_U32    iWidth,
66     OMX_U32    iHeight
67)
68{
69    OMX_S32     HalfCoeff, pos;
70    OMX_INT     y, x;
71
72    /* check for argument error */
73    armRetArgErrIf(pSrc == NULL, OMX_Sts_BadArgErr)
74    armRetArgErrIf(pDst == NULL, OMX_Sts_BadArgErr)
75
76
77    for (y = 0; y < iHeight; y++)
78    {
79        for (x = 0; x < iWidth; x++)
80        {
81            pos = y * iSrcStep + x;
82            HalfCoeff =
83                pSrc [pos - 2 * iSrcStep] -
84                5 * pSrc [pos - 1 * iSrcStep] +
85                20 * pSrc [pos] +
86                20 * pSrc [pos + 1 * iSrcStep] -
87                5 * pSrc [pos + 2 * iSrcStep] +
88                pSrc [pos + 3 * iSrcStep];
89
90            HalfCoeff = (HalfCoeff + 16) >> 5;
91            HalfCoeff = armClip(0, 255, HalfCoeff);
92
93            pDst [y * iDstStep + x] = (OMX_U8) HalfCoeff;
94        }
95    }
96
97    return OMX_Sts_NoErr;
98}
99
100