/* This is AGAST and OAST, an optimal and accelerated corner detector
based on the accelerated segment tests
Below is the original copyright and the references */
/*
Copyright (C) 2010 Elmar Mair
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
*Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
*Redistributions 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.
*Neither the name of the University of Cambridge nor the names of
its contributors may be used to endorse or promote products derived
from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
The references are:
* Adaptive and Generic Corner Detection Based on the Accelerated Segment Test,
Elmar Mair and Gregory D. Hager and Darius Burschka
and Michael Suppa and Gerhard Hirzinger ECCV 2010
URL: http://www6.in.tum.de/Main/ResearchAgast
*/
#include "agast_score.hpp"
#ifdef _MSC_VER
#pragma warning( disable : 4127 )
#endif
namespace cv
{
void makeAgastOffsets(int pixel[16], int rowStride, int type)
{
static const int offsets16[][2] =
{
{-3, 0}, {-3, -1}, {-2, -2}, {-1, -3}, {0, -3}, { 1, -3}, { 2, -2}, { 3, -1},
{ 3, 0}, { 3, 1}, { 2, 2}, { 1, 3}, {0, 3}, {-1, 3}, {-2, 2}, {-3, 1}
};
static const int offsets12d[][2] =
{
{-3, 0}, {-2, -1}, {-1, -2}, {0, -3}, { 1, -2}, { 2, -1},
{ 3, 0}, { 2, 1}, { 1, 2}, {0, 3}, {-1, 2}, {-2, 1}
};
static const int offsets12s[][2] =
{
{-2, 0}, {-2, -1}, {-1, -2}, {0, -2}, { 1, -2}, { 2, -1},
{ 2, 0}, { 2, 1}, { 1, 2}, {0, 2}, {-1, 2}, {-2, 1}
};
static const int offsets8[][2] =
{
{-1, 0}, {-1, -1}, {0, -1}, { 1, -1},
{ 1, 0}, { 1, 1}, {0, 1}, {-1, 1}
};
const int (*offsets)[2] = type == AgastFeatureDetector::OAST_9_16 ? offsets16 :
type == AgastFeatureDetector::AGAST_7_12d ? offsets12d :
type == AgastFeatureDetector::AGAST_7_12s ? offsets12s :
type == AgastFeatureDetector::AGAST_5_8 ? offsets8 : 0;
CV_Assert(pixel && offsets);
int k = 0;
for( ; k < 16; k++ )
pixel[k] = offsets[k][0] + offsets[k][1] * rowStride;
}
// 16 pixel mask
template<>
int agast_cornerScore<AgastFeatureDetector::OAST_9_16>(const uchar* ptr, const int pixel[], int threshold)
{
int bmin = threshold;
int bmax = 255;
int b_test = (bmax + bmin) / 2;
short offset0 = (short) pixel[0];
short offset1 = (short) pixel[1];
short offset2 = (short) pixel[2];
short offset3 = (short) pixel[3];
short offset4 = (short) pixel[4];
short offset5 = (short) pixel[5];
short offset6 = (short) pixel[6];
short offset7 = (short) pixel[7];
short offset8 = (short) pixel[8];
short offset9 = (short) pixel[9];
short offset10 = (short) pixel[10];
short offset11 = (short) pixel[11];
short offset12 = (short) pixel[12];
short offset13 = (short) pixel[13];
short offset14 = (short) pixel[14];
short offset15 = (short) pixel[15];
while(true)
{
const int cb = *ptr + b_test;
const int c_b = *ptr - b_test;
if(ptr[offset0] > cb)
if(ptr[offset2] > cb)
if(ptr[offset4] > cb)
if(ptr[offset5] > cb)
if(ptr[offset7] > cb)
if(ptr[offset3] > cb)
if(ptr[offset1] > cb)
if(ptr[offset6] > cb)
if(ptr[offset8] > cb)
goto is_a_corner;
else
if(ptr[offset15] > cb)
goto is_a_corner;
else
goto is_not_a_corner;
else
if(ptr[offset13] > cb)
if(ptr[offset14] > cb)
if(ptr[offset15] > cb)
goto is_a_corner;
else
goto is_not_a_corner;
else
goto is_not_a_corner;
else
goto is_not_a_corner;
else
if(ptr[offset8] > cb)
if(ptr[offset9] > cb)
if(ptr[offset10] > cb)
if(ptr[offset6] > cb)
goto is_a_corner;
else
if(ptr[offset11] > cb)
if(ptr[offset12] > cb)
if(ptr[offset13] > cb)
if(ptr[offset14] > cb)
if(ptr[offset15] > cb)
goto is_a_corner;
else
goto is_not_a_corner;
else
goto is_not_a_corner;
else
goto is_not_a_corner;
else
goto is_not_a_corner;
else
goto is_not_a_corner;
else
goto is_not_a_corner;
else
goto is_not_a_corner;
else
goto is_not_a_corner;
else
if(ptr[offset10] > cb)
if(ptr[offset11] > cb)
if(ptr[offset12] > cb)
if(ptr[offset8] > cb)
if(ptr[offset9] > cb)
if(ptr[offset6] > cb)
goto is_a_corner;
else
if(ptr[offset13] > cb)
if(ptr[offset14] > cb)
if(ptr[offset15] > cb)
goto is_a_corner;
else
goto is_not_a_corner;
else
goto is_not_a_corner;
else
goto is_not_a_corner;
else
if(ptr[offset1] > cb)
if(ptr[offset13] > cb)
if(ptr[offset14] > cb)
if(ptr[offset15] > cb)
goto is_a_corner;
else
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