1/*M///////////////////////////////////////////////////////////////////////////////////////
2//
3//  IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING.
4//
5//  By downloading, copying, installing or using the software you agree to this license.
6//  If you do not agree to this license, do not download, install,
7//  copy or use the software.
8//
9//
10//                           License Agreement
11//                For Open Source Computer Vision Library
12//
13// Copyright (C) 2010-2012, Institute Of Software Chinese Academy Of Science, all rights reserved.
14// Copyright (C) 2010-2012, Advanced Micro Devices, Inc., all rights reserved.
15// Third party copyrights are property of their respective owners.
16//
17// @Authors
18//    Shengen Yan,yanshengen@gmail.com
19//
20// Redistribution and use in source and binary forms, with or without modification,
21// are permitted provided that the following conditions are met:
22//
23//   * Redistribution's of source code must retain the above copyright notice,
24//     this list of conditions and the following disclaimer.
25//
26//   * Redistribution's in binary form must reproduce the above copyright notice,
27//     this list of conditions and the following disclaimer in the documentation
28//     and/or other materials provided with the distribution.
29//
30//   * The name of the copyright holders may not be used to endorse or promote products
31//     derived from this software without specific prior written permission.
32//
33// This software is provided by the copyright holders and contributors as is and
34// any express or implied warranties, including, but not limited to, the implied
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36// In no event shall the Intel Corporation or contributors be liable for any direct,
37// indirect, incidental, special, exemplary, or consequential damages
38// (including, but not limited to, procurement of substitute goods or services;
39// loss of use, data, or profits; or business interruption) however caused
40// and on any theory of liability, whether in contract, strict liability,
41// or tort (including negligence or otherwise) arising in any way out of
42// the use of this software, even if advised of the possibility of such damage.
43//
44//M*/
45
46__kernel void preCornerDetect(__global const uchar * Dxptr, int dx_step, int dx_offset,
47                              __global const uchar * Dyptr, int dy_step, int dy_offset,
48                              __global const uchar * D2xptr, int d2x_step, int d2x_offset,
49                              __global const uchar * D2yptr, int d2y_step, int d2y_offset,
50                              __global const uchar * Dxyptr, int dxy_step, int dxy_offset,
51                              __global uchar * dstptr, int dst_step, int dst_offset,
52                              int dst_rows, int dst_cols, float factor)
53{
54    int x = get_global_id(0);
55    int y = get_global_id(1);
56
57    if (x < dst_cols && y < dst_rows)
58    {
59        int dx_index = mad24(dx_step, y, (int)sizeof(float) * x + dx_offset);
60        int dy_index = mad24(dy_step, y, (int)sizeof(float) * x + dy_offset);
61        int d2x_index = mad24(d2x_step, y, (int)sizeof(float) * x + d2x_offset);
62        int d2y_index = mad24(d2y_step, y, (int)sizeof(float) * x + d2y_offset);
63        int dxy_index = mad24(dxy_step, y, (int)sizeof(float) * x + dxy_offset);
64        int dst_index = mad24(dst_step, y, (int)sizeof(float) * x + dst_offset);
65
66        float dx = *(__global const float *)(Dxptr + dx_index);
67        float dy = *(__global const float *)(Dyptr + dy_index);
68        float d2x = *(__global const float *)(D2xptr + d2x_index);
69        float d2y = *(__global const float *)(D2yptr + d2y_index);
70        float dxy = *(__global const float *)(Dxyptr + dxy_index);
71        __global float * dst = (__global float *)(dstptr + dst_index);
72
73        dst[0] = factor * (dx*dx*d2y + dy*dy*d2x - 2*dx*dy*dxy);
74    }
75}
76