/*M///////////////////////////////////////////////////////////////////////////////////////
//
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//
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// If you do not agree to this license, do not download, install,
// copy or use the software.
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//
// License Agreement
// For Open Source Computer Vision Library
//
// Copyright (C) 2010-2012, Institute Of Software Chinese Academy Of Science, all rights reserved.
// Copyright (C) 2010-2012, Advanced Micro Devices, Inc., all rights reserved.
// Third party copyrights are property of their respective owners.
//
// @Authors
// Shengen Yan,yanshengen@gmail.com
//
// Redistribution and use in source and binary forms, with or without modification,
// are permitted provided that the following conditions are met:
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// * Redistribution's of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
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// * Redistribution's in binary form must reproduce the above copyright notice,
// this list of conditions and the following disclaimer in the documentation
// and/or other materials provided with the distribution.
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// * The name of the copyright holders may not be used to endorse or promote products
// derived from this software without specific prior written permission.
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//M*/
__kernel void preCornerDetect(__global const uchar * Dxptr, int dx_step, int dx_offset,
__global const uchar * Dyptr, int dy_step, int dy_offset,
__global const uchar * D2xptr, int d2x_step, int d2x_offset,
__global const uchar * D2yptr, int d2y_step, int d2y_offset,
__global const uchar * Dxyptr, int dxy_step, int dxy_offset,
__global uchar * dstptr, int dst_step, int dst_offset,
int dst_rows, int dst_cols, float factor)
{
int x = get_global_id(0);
int y = get_global_id(1);
if (x < dst_cols && y < dst_rows)
{
int dx_index = mad24(dx_step, y, (int)sizeof(float) * x + dx_offset);
int dy_index = mad24(dy_step, y, (int)sizeof(float) * x + dy_offset);
int d2x_index = mad24(d2x_step, y, (int)sizeof(float) * x + d2x_offset);
int d2y_index = mad24(d2y_step, y, (int)sizeof(float) * x + d2y_offset);
int dxy_index = mad24(dxy_step, y, (int)sizeof(float) * x + dxy_offset);
int dst_index = mad24(dst_step, y, (int)sizeof(float) * x + dst_offset);
float dx = *(__global const float *)(Dxptr + dx_index);
float dy = *(__global const float *)(Dyptr + dy_index);
float d2x = *(__global const float *)(D2xptr + d2x_index);
float d2y = *(__global const float *)(D2yptr + d2y_index);
float dxy = *(__global const float *)(Dxyptr + dxy_index);
__global float * dst = (__global float *)(dstptr + dst_index);
dst[0] = factor * (dx*dx*d2y + dy*dy*d2x - 2*dx*dy*dxy);
}
}