From c83455d8a42c03d4ed213238ebd4d6758ffbcb92 Mon Sep 17 00:00:00 2001
From: Ilya Lavrenov <ilya.lavrenov@itseez.com>
Date: Fri, 23 May 2014 12:45:24 +0300
Subject: [PATCH] optimized cv::repeat

---
 modules/core/src/copy.cpp         | 28 ++++++++++++++++-------
 modules/core/src/ocl.cpp          |  4 ++--
 modules/core/src/opencl/repeat.cl | 47 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 69 insertions(+), 10 deletions(-)
 create mode 100644 modules/core/src/opencl/repeat.cl

diff --git a/modules/core/src/copy.cpp b/modules/core/src/copy.cpp
index be93577..4fbc593 100644
--- a/modules/core/src/copy.cpp
+++ b/modules/core/src/copy.cpp
@@ -758,16 +758,28 @@ void flip( InputArray _src, OutputArray _dst, int flip_mode )
 
 static bool ocl_repeat(InputArray _src, int ny, int nx, OutputArray _dst)
 {
+    if (ny == 1 && nx == 1)
+    {
+        _src.copyTo(_dst);
+        return true;
+    }
+
+    int type = _src.type(), depth = CV_MAT_DEPTH(type), cn = CV_MAT_CN(type),
+            rowsPerWI = ocl::Device::getDefault().isIntel() ? 4 : 1,
+            kercn = std::min(ocl::predictOptimalVectorWidth(_src, _dst), 4);
+
+    ocl::Kernel k("repeat", ocl::core::repeat_oclsrc,
+                  format("-D T=%s -D nx=%d -D ny=%d -D rowsPerWI=%d -D cn=%d",
+                         ocl::memopTypeToStr(CV_MAKE_TYPE(depth, kercn)),
+                         nx, ny, rowsPerWI, kercn));
+    if (k.empty())
+        return false;
+
     UMat src = _src.getUMat(), dst = _dst.getUMat();
+    k.args(ocl::KernelArg::ReadOnly(src, cn, kercn), ocl::KernelArg::WriteOnlyNoSize(dst));
 
-    for (int y = 0; y < ny; ++y)
-        for (int x = 0; x < nx; ++x)
-        {
-            Rect roi(x * src.cols, y * src.rows, src.cols, src.rows);
-            UMat hdr(dst, roi);
-            src.copyTo(hdr);
-        }
-    return true;
+    size_t globalsize[] = { src.cols * cn / kercn, (src.rows + rowsPerWI - 1) / rowsPerWI };
+    return k.run(2, globalsize, NULL, false);
 }
 
 #endif
diff --git a/modules/core/src/ocl.cpp b/modules/core/src/ocl.cpp
index 9d6a1b5..96c17c8 100644
--- a/modules/core/src/ocl.cpp
+++ b/modules/core/src/ocl.cpp
@@ -4406,8 +4406,8 @@ String kernelToStr(InputArray _kernel, int ddepth, const char * name)
             CV_Assert(src.isMat() || src.isUMat()); \
             int ctype = src.type(), ccn = CV_MAT_CN(ctype); \
             Size csize = src.size(); \
-            cols.push_back(ccn * src.size().width); \
-            if (ctype != type || csize != ssize) \
+            cols.push_back(ccn * csize.width); \
+            if (ctype != type) \
                 return 1; \
             offsets.push_back(src.offset()); \
             steps.push_back(src.step()); \
diff --git a/modules/core/src/opencl/repeat.cl b/modules/core/src/opencl/repeat.cl
new file mode 100644
index 0000000..21be121
--- /dev/null
+++ b/modules/core/src/opencl/repeat.cl
@@ -0,0 +1,47 @@
+// This file is part of OpenCV project.
+// It is subject to the license terms in the LICENSE file found in the top-level directory
+// of this distribution and at http://opencv.org/license.html.
+
+// Copyright (C) 2014, Itseez, Inc., all rights reserved.
+// Third party copyrights are property of their respective owners.
+
+#if cn != 3
+#define loadpix(addr) *(__global const T *)(addr)
+#define storepix(val, addr)  *(__global T *)(addr) = val
+#define TSIZE (int)sizeof(T)
+#else
+#define loadpix(addr) vload3(0, (__global const T1 *)(addr))
+#define storepix(val, addr) vstore3(val, 0, (__global T1 *)(addr))
+#define TSIZE ((int)sizeof(T1)*3)
+#endif
+
+__kernel void repeat(__global const uchar * srcptr, int src_step, int src_offset, int src_rows, int src_cols,
+                     __global uchar * dstptr, int dst_step, int dst_offset)
+{
+    int x = get_global_id(0);
+    int y0 = get_global_id(1) * rowsPerWI;
+
+    if (x < src_cols)
+    {
+        int src_index = mad24(y0, src_step, mad24(x, (int)sizeof(T), src_offset));
+        int dst_index0 = mad24(y0, dst_step, mad24(x, (int)sizeof(T), dst_offset));
+
+        for (int y = y0, y1 = min(src_rows, y0 + rowsPerWI); y < y1; ++y, src_index += src_step, dst_index0 += dst_step)
+        {
+            T srcelem = loadpix(srcptr + src_index);
+
+            #pragma unroll
+            for (int ey = 0; ey < ny; ++ey)
+            {
+                int dst_index = mad24(ey * src_rows, dst_step, dst_index0);
+
+                #pragma unroll
+                for (int ex = 0; ex < nx; ++ex)
+                {
+                    storepix(srcelem, dstptr + dst_index);
+                    dst_index = mad24(src_cols, (int)sizeof(T), dst_index);
+                }
+            }
+        }
+    }
+}
-- 
2.7.4