JavaScript bindings for features2d module

modules/features2d/CMakeLists.txt

 set(the_description "2D Features Framework")
-ocv_define_module(features2d opencv_imgproc OPTIONAL opencv_flann opencv_highgui WRAP java python)
+ocv_define_module(features2d opencv_imgproc OPTIONAL opencv_flann opencv_highgui WRAP java python js)

modules/features2d/include/opencv2/features2d.hpp

@@ -137,7 +137,11 @@ public:
 
 /** @brief Abstract base class for 2D image feature detectors and descriptor extractors
 */
+#ifdef __EMSCRIPTEN__
+class CV_EXPORTS_W Feature2D : public Algorithm
+#else
 class CV_EXPORTS_W Feature2D : public virtual Algorithm
+#endif
 {
 public:
     virtual ~Feature2D();

modules/js/src/embindgen.py

@@ -126,7 +126,22 @@ video = {'': ['CamShift', 'calcOpticalFlowFarneback', 'calcOpticalFlowPyrLK', 'c
          'BackgroundSubtractor': ['apply', 'getBackgroundImage']}
 
 dnn = {'dnn_Net': ['setInput', 'forward'],
-       '': ['readNetFromCaffe', 'readNetFromTensorflow', 'readNetFromTorch', 'readNetFromDarknet', 'blobFromImage']}
+       '': ['readNetFromCaffe', 'readNetFromTensorflow', 'readNetFromTorch', 'readNetFromDarknet',
+            'readNetFromONNX', 'readNet', 'blobFromImage']}
+
+features2d = {'Feature2D': ['detect', 'compute', 'detectAndCompute', 'descriptorSize', 'descriptorType', 'defaultNorm', 'empty', 'getDefaultName'],
+              'BRISK': ['create', 'getDefaultName'],
+              'ORB': ['create', 'setMaxFeatures', 'setScaleFactor', 'setNLevels', 'setEdgeThreshold', 'setFirstLevel', 'setWTA_K', 'setScoreType', 'setPatchSize', 'getFastThreshold', 'getDefaultName'],
+              'MSER': ['create', 'detectRegions', 'setDelta', 'getDelta', 'setMinArea', 'getMinArea', 'setMaxArea', 'getMaxArea', 'setPass2Only', 'getPass2Only', 'getDefaultName'],
+              'FastFeatureDetector': ['create', 'setThreshold', 'getThreshold', 'setNonmaxSuppression', 'getNonmaxSuppression', 'setType', 'getType', 'getDefaultName'],
+              'AgastFeatureDetector': ['create', 'setThreshold', 'getThreshold', 'setNonmaxSuppression', 'getNonmaxSuppression', 'setType', 'getType', 'getDefaultName'],
+              'GFTTDetector': ['create', 'setMaxFeatures', 'getMaxFeatures', 'setQualityLevel', 'getQualityLevel', 'setMinDistance', 'getMinDistance', 'setBlockSize', 'getBlockSize', 'setHarrisDetector', 'getHarrisDetector', 'setK', 'getK', 'getDefaultName'],
+              # 'SimpleBlobDetector': ['create'],
+              'KAZE': ['create', 'setExtended', 'getExtended', 'setUpright', 'getUpright', 'setThreshold', 'getThreshold', 'setNOctaves', 'getNOctaves', 'setNOctaveLayers', 'getNOctaveLayers', 'setDiffusivity', 'getDiffusivity', 'getDefaultName'],
+              'AKAZE': ['create', 'setDescriptorType', 'getDescriptorType', 'setDescriptorSize', 'getDescriptorSize', 'setDescriptorChannels', 'getDescriptorChannels', 'setThreshold', 'getThreshold', 'setNOctaves', 'getNOctaves', 'setNOctaveLayers', 'getNOctaveLayers', 'setDiffusivity', 'getDiffusivity', 'getDefaultName'],
+              'DescriptorMatcher': ['add', 'clear', 'empty', 'isMaskSupported', 'train', 'match', 'knnMatch', 'radiusMatch', 'clone', 'create'],
+              'BFMatcher': ['isMaskSupported', 'create'],
+              '': ['FAST', 'AGAST', 'drawKeypoints', 'drawMatches']}
 
 def makeWhiteList(module_list):
     wl = {}
@@ -138,7 +153,7 @@ def makeWhiteList(module_list):
                 wl[k] = m[k]
     return wl
 
-white_list = makeWhiteList([core, imgproc, objdetect, video, dnn])
+white_list = makeWhiteList([core, imgproc, objdetect, video, dnn, features2d])
 
 # Features to be exported
 export_enums = False
@@ -219,7 +234,8 @@ def handle_ptr(tp):
 
 def handle_vector(tp):
     if tp.startswith('vector_'):
-        tp = 'std::vector<' + "::".join(tp.split('_')[1:]) + '>'
+        tp = handle_vector(tp[tp.find('_') + 1:])
+        tp = 'std::vector<' + "::".join(tp.split('_')) + '>'
     return tp
 
 
@@ -845,13 +861,12 @@ class JSWrapperGenerator(object):
                     [class_info.cname, property.name])))
 
             dv = ''
-            base = Template("""base<$base$isPoly>""")
+            base = Template("""base<$base>""")
 
             assert len(class_info.bases) <= 1 , "multiple inheritance not supported"
 
             if len(class_info.bases) == 1:
-                dv = "," + base.substitute(base=', '.join(class_info.bases),
-                                           isPoly = " ,true" if class_info.name=="Feature2D" else "")
+                dv = "," + base.substitute(base=', '.join(class_info.bases))
 
             self.bindings.append(class_template.substitute(cpp_name=class_info.cname,
                                                            js_name=name,

platforms/js/build_js.py

@@ -131,7 +131,7 @@ class Builder:
                "-DBUILD_opencv_apps=OFF",
                "-DBUILD_opencv_calib3d=OFF",
                "-DBUILD_opencv_dnn=ON",
-               "-DBUILD_opencv_features2d=OFF",
+               "-DBUILD_opencv_features2d=ON",
                "-DBUILD_opencv_flann=OFF",
                "-DBUILD_opencv_ml=OFF",
                "-DBUILD_opencv_photo=OFF",