COMP: Fix unit tests for OpenCV 4

Modules/Video/BridgeOpenCV/include/itkOpenCVVideoCapture.hxx

@@ -23,10 +23,13 @@
 #include "itkImageRegionConstIteratorWithIndex.h"
 
 #include "opencv2/core/version.hpp"
-#if !defined(CV_VERSION_EPOCH)
-// OpenCV 3.x
+#if !defined(CV_VERSION_EPOCH) // OpenCV >= 3.0
 #  include "opencv2/videoio.hpp"
 #  include "opencv2/imgproc/types_c.h" // CV_RGB2BGR, CV_BGR2GRAY, ...
+#  include "opencv2/imgproc/imgproc_c.h"
+#  if CV_VERSION_MAJOR > 3 // OpenCV 4.x
+#    include "opencv2/videoio/legacy/constants_c.h"
+#  endif
 #else
 // OpenCV 2.4.x
 #  include "cv.h"

Modules/Video/BridgeOpenCV/test/CMakeLists.txt

@@ -12,7 +12,9 @@ include_directories(${ITKVideoBridgeOpenCV_INCLUDE_DIRS})
 
 CreateTestDriver(ITKVideoBridgeOpenCV
   "${ITKVideoBridgeOpenCV-Test_LIBRARIES};${OpenCV_LIBS}"
-  "${ITKVideoBridgeOpenCVTests}")
+  "${ITKVideoBridgeOpenCVTests}"
+  itkOpenCVTestHelper.cxx
+  )
 
 # OpenCVVideoCapture:
 itk_add_test(NAME

Modules/Video/BridgeOpenCV/test/itkOpenCVImageBridgeGrayScaleTest.cxx

@@ -23,6 +23,7 @@
 #include "itkTestingComparisonImageFilter.h"
 #include "itkImageRegionConstIteratorWithIndex.h"
 #include "itkOpenCVVideoIOFactory.h"
+#include "itkOpenCVTestHelper.h"
 
 #if defined(CV_VERSION_EPOCH) // OpenCV 2.4.x
 #  include "highgui.h"

Modules/Video/BridgeOpenCV/test/itkOpenCVImageBridgeRGBTest.cxx

@@ -22,6 +22,7 @@
 #include "itkImageFileReader.h"
 #include "itkImageRegionConstIteratorWithIndex.h"
 #include "itkOpenCVVideoIOFactory.h"
+#include "itkOpenCVTestHelper.h"
 
 #if defined(CV_VERSION_EPOCH) // OpenCV 2.4.x
 #  include "highgui.h"

Modules/Video/BridgeOpenCV/test/itkOpenCVTestHelper.cxx

@@ -0,0 +1,47 @@
+/*=========================================================================
+ *
+ *  Copyright Insight Software Consortium
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *         http://www.apache.org/licenses/LICENSE-2.0.txt
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ *
+ *=========================================================================*/
+#include "itkOpenCVTestHelper.h"
+
+#include <map>
+
+#include "opencv2/core/version.hpp"
+#include "opencv2/imgcodecs.hpp" // cv::imread
+
+#if CV_VERSION_MAJOR > 3 // OpenCV >= 4.0
+#  include "opencv2/imgcodecs/legacy/constants_c.h"
+#  include <opencv2/core/core_c.h>
+#else                                        // OpenCV < 4.0
+#  include "opencv2/imgcodecs/imgcodecs_c.h" // CV_LOAD_IMAGE_COLOR
+#endif
+
+#if CV_VERSION_MAJOR > 3
+// Based on https://stackoverflow.com/a/13683381/471839
+IplImage *
+cvLoadImage(const char * filename, int iscolor)
+{
+  std::map<int, int> matDepthToIplDepth{ { CV_8U, IPL_DEPTH_8U },   { CV_8S, IPL_DEPTH_8S },
+                                         { CV_16U, IPL_DEPTH_16U }, { CV_16S, IPL_DEPTH_16S },
+                                         { CV_32S, IPL_DEPTH_32S }, { CV_32F, IPL_DEPTH_32F },
+                                         { CV_64F, IPL_DEPTH_64F } };
+  cv::Mat            mat = cv::imread(filename, iscolor);
+  IplImage *         ipl = cvCreateImage(cvSize(mat.cols, mat.rows), matDepthToIplDepth[mat.depth()], mat.channels());
+  IplImage           iplTemp = mat;
+  cvCopy(&iplTemp, ipl);
+  return ipl;
+}
+#endif

Modules/Video/BridgeOpenCV/test/itkOpenCVTestHelper.h

@@ -0,0 +1,31 @@
+/*=========================================================================
+ *
+ *  Copyright Insight Software Consortium
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *         http://www.apache.org/licenses/LICENSE-2.0.txt
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ *
+ *=========================================================================*/
+#ifndef itkOpenCVTestHelper_h
+#define itkOpenCVTestHelper_h
+
+#include <opencv2/core/types_c.h>
+#include <opencv2/core/version.hpp>
+
+#if CV_VERSION_MAJOR > 3
+// This is a shim to support tests that depend on loading IplImages via the
+// obsolete C API that was dropped in OpenCV 4.
+IplImage *
+cvLoadImage(const char * filename, int iscolor);
+#endif
+
+#endif // itkOpenCVTestHelper_h