split FAST in order to reuse it in BRISK

modules/features2d/src/fast_score.hpp

+/* This is FAST corner detector, contributed to OpenCV by the author, Edward Rosten.
+   Below is the original copyright and the references */
+
+/*
+Copyright (c) 2006, 2008 Edward Rosten
+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:
+ * Machine learning for high-speed corner detection,
+   E. Rosten and T. Drummond, ECCV 2006
+ * Faster and better: A machine learning approach to corner detection
+   E. Rosten, R. Porter and T. Drummond, PAMI, 2009
+*/
+
+#ifndef __OPENCV_FEATURES_2D_FAST_HPP__
+#define __OPENCV_FEATURES_2D_FAST_HPP__
+
+#ifdef __cplusplus
+
+#include "precomp.hpp"
+
+namespace cv
+{
+
+void makeOffsets(int pixel[25], int row_stride, int patternSize);
+
+//static void testCorner(const uchar* ptr, const int pixel[], int K, int N, int threshold);
+
+template<int patternSize>
+int cornerScore(const uchar* ptr, const int pixel[], int threshold);
+
+}
+
+#endif
+#endif