From 2241bfb0dfa788e0b516a7da9a1f70733f5431d3 Mon Sep 17 00:00:00 2001
From: Namgoo Lee <namgoo.lee@cognex.com>
Date: Thu, 30 Jul 2020 01:03:34 +0900
Subject: [PATCH 1/2] Use "src" not "*this" for source GpuMat

---
 modules/core/src/cuda/gpu_mat.cu | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/modules/core/src/cuda/gpu_mat.cu b/modules/core/src/cuda/gpu_mat.cu
index e1b0c1b22d..f31f78a87a 100644
--- a/modules/core/src/cuda/gpu_mat.cu
+++ b/modules/core/src/cuda/gpu_mat.cu
@@ -561,7 +561,7 @@ void cv::cuda::GpuMat::convertTo(OutputArray _dst, int rtype, Stream& stream) co
         {convertToNoScale<double, uchar>, convertToNoScale<double, schar>, convertToNoScale<double, ushort>, convertToNoScale<double, short>, convertToNoScale<double, int>, convertToNoScale<double, float>, 0}
     };
 
-    funcs[sdepth][ddepth](reshape(1), dst.reshape(1), stream);
+    funcs[sdepth][ddepth](src.reshape(1), dst.reshape(1), stream);
 }
 
 void cv::cuda::GpuMat::convertTo(OutputArray _dst, int rtype, double alpha, double beta, Stream& stream) const
@@ -591,7 +591,7 @@ void cv::cuda::GpuMat::convertTo(OutputArray _dst, int rtype, double alpha, doub
         {convertToScale<double, uchar>, convertToScale<double, schar>, convertToScale<double, ushort>, convertToScale<double, short>, convertToScale<double, int>, convertToScale<double, float>, convertToScale<double, double>}
     };
 
-    funcs[sdepth][ddepth](reshape(1), dst.reshape(1), alpha, beta, stream);
+    funcs[sdepth][ddepth](src.reshape(1), dst.reshape(1), alpha, beta, stream);
 }
 
 void cv::cuda::convertFp16(InputArray _src, OutputArray _dst, Stream& stream)

From 11ac26bfb43ad6e10c2bd50bbba0489e2bc26a79 Mon Sep 17 00:00:00 2001
From: Namgoo Lee <namgoo.lee@cognex.com>
Date: Thu, 30 Jul 2020 01:24:25 +0900
Subject: [PATCH 2/2] test code

---
 modules/cudaarithm/test/test_gpumat.cpp | 59 +++++++++++++++++++++++++
 1 file changed, 59 insertions(+)

diff --git a/modules/cudaarithm/test/test_gpumat.cpp b/modules/cudaarithm/test/test_gpumat.cpp
index e2fed16ad5..b4d59b1644 100644
--- a/modules/cudaarithm/test/test_gpumat.cpp
+++ b/modules/cudaarithm/test/test_gpumat.cpp
@@ -320,6 +320,65 @@ CUDA_TEST_P(GpuMat_ConvertTo, WithScaling)
     }
 }
 
+CUDA_TEST_P(GpuMat_ConvertTo, InplaceWithOutScaling)
+{
+    cv::Mat src = randomMat(size, depth1);
+
+    if ((depth1 == CV_64F || depth2 == CV_64F) && !supportFeature(devInfo, cv::cuda::NATIVE_DOUBLE))
+    {
+        try
+        {
+            cv::cuda::GpuMat d_srcDst = loadMat(src);
+            d_srcDst.convertTo(d_srcDst, depth2);
+        }
+        catch (const cv::Exception& e)
+        {
+            ASSERT_EQ(cv::Error::StsUnsupportedFormat, e.code);
+        }
+    }
+    else
+    {
+        cv::cuda::GpuMat d_srcDst = loadMat(src, useRoi);
+        d_srcDst.convertTo(d_srcDst, depth2);
+
+        cv::Mat dst_gold;
+        src.convertTo(dst_gold, depth2);
+
+        EXPECT_MAT_NEAR(dst_gold, d_srcDst, depth2 < CV_32F ? 1.0 : 1e-4);
+    }
+}
+
+
+CUDA_TEST_P(GpuMat_ConvertTo, InplaceWithScaling)
+{
+    cv::Mat src = randomMat(size, depth1);
+    double a = randomDouble(0.0, 1.0);
+    double b = randomDouble(-10.0, 10.0);
+
+    if ((depth1 == CV_64F || depth2 == CV_64F) && !supportFeature(devInfo, cv::cuda::NATIVE_DOUBLE))
+    {
+        try
+        {
+            cv::cuda::GpuMat d_srcDst = loadMat(src);
+            d_srcDst.convertTo(d_srcDst, depth2, a, b);
+        }
+        catch (const cv::Exception& e)
+        {
+            ASSERT_EQ(cv::Error::StsUnsupportedFormat, e.code);
+        }
+    }
+    else
+    {
+        cv::cuda::GpuMat d_srcDst = loadMat(src, useRoi);
+        d_srcDst.convertTo(d_srcDst, depth2, a, b);
+
+        cv::Mat dst_gold;
+        src.convertTo(dst_gold, depth2, a, b);
+
+        EXPECT_MAT_NEAR(dst_gold, d_srcDst, depth2 < CV_32F ? 1.0 : 1e-4);
+    }
+}
+
 INSTANTIATE_TEST_CASE_P(CUDA, GpuMat_ConvertTo, testing::Combine(
     ALL_DEVICES,
     DIFFERENT_SIZES,