1/**
2 *
3 * File Name:  armVCM4P10_InterpolateHalfVer_Luma.c
4 * OpenMAX DL: v1.0.2
5 * Revision:   9641
6 * Date:       Thursday, February 7, 2008
7 *
8 * (c) Copyright 2007-2008 ARM Limited. All Rights Reserved.
9 *
10 *
11 * Description:
12 * This functions will help to calculate Half Pel luma interpolation
13 *
14 */
15
16#include "omxtypes.h"
17#include "armOMX.h"
18#include "omxVC.h"
19
20#include "armCOMM.h"
21#include "armVC.h"
22
23/**
24 * Function: armVCM4P10_InterpolateHalfVer_Luma
25 *
26 * Description:
27 * This function performs interpolation for vertical 1/2-pel positions
28 * around a full-pel position.
29 *
30 * Remarks:
31 *
32 *  [in]    pSrc        Pointer to top-left corner of block used to interpolate
33 *                      in the reconstructed frame plane
34 *  [in]    iSrcStep    Step of the source buffer.
35 *  [in]    iDstStep    Step of the destination(interpolation) buffer.
36 *  [in]    iWidth      Width of the current block
37 *  [in]    iHeight     Height of the current block
38 *  [out]   pDst        Pointer to the interpolation buffer of the 1/2-pel
39 *
40 * Return Value:
41 * Standard OMXResult value.
42 *
43 */
44
45OMXResult armVCM4P10_InterpolateHalfVer_Luma(
46     const OMX_U8*    pSrc,
47     OMX_U32    iSrcStep,
48     OMX_U8*    pDst,
49     OMX_U32    iDstStep,
50     OMX_U32    iWidth,
51     OMX_U32    iHeight
52)
53{
54    OMX_S32     HalfCoeff, pos;
55    OMX_INT     y, x;
56
57    /* check for argument error */
58    armRetArgErrIf(pSrc == NULL, OMX_Sts_BadArgErr)
59    armRetArgErrIf(pDst == NULL, OMX_Sts_BadArgErr)
60
61
62    for (y = 0; y < iHeight; y++)
63    {
64        for (x = 0; x < iWidth; x++)
65        {
66            pos = y * iSrcStep + x;
67            HalfCoeff =
68                pSrc [pos - 2 * iSrcStep] -
69                5 * pSrc [pos - 1 * iSrcStep] +
70                20 * pSrc [pos] +
71                20 * pSrc [pos + 1 * iSrcStep] -
72                5 * pSrc [pos + 2 * iSrcStep] +
73                pSrc [pos + 3 * iSrcStep];
74
75            HalfCoeff = (HalfCoeff + 16) >> 5;
76            HalfCoeff = armClip(0, 255, HalfCoeff);
77
78            pDst [y * iDstStep + x] = (OMX_U8) HalfCoeff;
79        }
80    }
81
82    return OMX_Sts_NoErr;
83}
84
85