From d9556a998ff22d6d9d8d2fd926f16f73921e84d2 Mon Sep 17 00:00:00 2001
From: Alexander Karsakov <alexander.karsakov@itseez.com>
Date: Thu, 10 Apr 2014 11:00:08 +0400
Subject: [PATCH] Added ippiMinEigenVal_ to cv::cornerMinEigenVal

---
 modules/imgproc/src/corner.cpp | 47 ++++++++++++++++++++++++++++++++++
 1 file changed, 47 insertions(+)

diff --git a/modules/imgproc/src/corner.cpp b/modules/imgproc/src/corner.cpp
index cc35ff2de5..1f9d7bda5a 100644
--- a/modules/imgproc/src/corner.cpp
+++ b/modules/imgproc/src/corner.cpp
@@ -460,6 +460,53 @@ void cv::cornerMinEigenVal( InputArray _src, OutputArray _dst, int blockSize, in
     Mat src = _src.getMat();
     _dst.create( src.size(), CV_32FC1 );
     Mat dst = _dst.getMat();
+
+#ifdef HAVE_IPP
+    typedef IppStatus (CV_STDCALL * ippiMinEigenValGetBufferSize)(IppiSize, int, int, int*);
+    typedef IppStatus (CV_STDCALL * ippiMinEigenVal)(const void*, int, Ipp32f*, int, IppiSize, IppiKernelType, int, int, Ipp8u*);
+
+    Size srcWholeSize; Point srcOffset;
+    src.locateROI(srcWholeSize, srcOffset);
+    if (borderType == BORDER_REPLICATE && srcWholeSize == src.size())
+    {
+        IppiKernelType kerType = ksize > 0 ? ippKernelSobel : ippKernelScharr;
+        IppiSize srcRoi = { src.cols, src.rows };
+
+        ippiMinEigenValGetBufferSize getBufferSizeFunc = 0;
+        ippiMinEigenVal minEigenValFunc = 0;
+        float multiplier = 0.f;
+
+        if (src.type() == CV_8UC1)
+        {
+            getBufferSizeFunc = (ippiMinEigenValGetBufferSize) ippiMinEigenValGetBufferSize_8u32f_C1R;
+            minEigenValFunc = (ippiMinEigenVal) ippiMinEigenVal_8u32f_C1R;
+            multiplier = (float) 1 / 255;
+        } else if (src.type() == CV_32FC1)
+        {
+            getBufferSizeFunc = (ippiMinEigenValGetBufferSize) ippiMinEigenValGetBufferSize_32f_C1R;
+            minEigenValFunc = (ippiMinEigenVal) ippiMinEigenVal_32f_C1R;
+            multiplier = 255.f;
+        }
+
+        if (getBufferSizeFunc && minEigenValFunc)
+        {
+            int bufferSize;
+            IppStatus ok = getBufferSizeFunc(srcRoi, ksize, blockSize, &bufferSize);
+            if (ok >= 0)
+            {
+
+                Ipp8u* buffer = ippsMalloc_8u(bufferSize);
+                ok = minEigenValFunc(src.data, src.step, (Ipp32f*) dst.data, (int) dst.step, srcRoi, kerType, ksize, blockSize, buffer);
+                ippsFree(buffer);
+                if (ok >= 0) 
+                {
+                    dst *= multiplier;
+                    return;
+                }
+            }
+        }
+    }
+#endif
     cornerEigenValsVecs( src, dst, blockSize, ksize, MINEIGENVAL, 0, borderType );
 }