python: exception-free pyopencv_to() wrapper

modules/python/src2/cv2.cpp

@@ -44,6 +44,7 @@
 
 #define CV_HAS_CONVERSION_ERROR(x) (((x) == -1) && PyErr_Occurred())
 
+static PyObject* opencv_error = NULL;
 
 class ArgInfo
 {
@@ -66,14 +67,32 @@ struct PyOpenCV_Converter
     //static inline PyObject* from(const T& src);
 };
 
+// exception-safe pyopencv_to
+template<typename _Tp> static
+bool pyopencv_to_safe(PyObject* obj, _Tp& value, const ArgInfo& info)
+{
+    try
+    {
+        return pyopencv_to(obj, value, info);
+    }
+    catch (const std::exception &e)
+    {
+        PyErr_SetString(opencv_error, cv::format("Conversion error: %s, what: %s", info.name, e.what()).c_str());
+        return false;
+    }
+    catch (...)
+    {
+        PyErr_SetString(opencv_error, cv::format("Conversion error: %s", info.name).c_str());
+        return false;
+    }
+}
+
 template<typename T> static
 bool pyopencv_to(PyObject* obj, T& p, const ArgInfo& info) { return PyOpenCV_Converter<T>::to(obj, p, info); }
 
 template<typename T> static
 PyObject* pyopencv_from(const T& src) { return PyOpenCV_Converter<T>::from(src); }
 
-static PyObject* opencv_error = NULL;
-
 static bool isPythonBindingsDebugEnabled()
 {
     static bool param_debug = cv::utils::getConfigurationParameterBool("OPENCV_PYTHON_DEBUG", false);
@@ -211,6 +230,11 @@ catch (const std::exception &e) \
 { \
     PyErr_SetString(opencv_error, e.what()); \
     return 0; \
+} \
+catch (...) \
+{ \
+    PyErr_SetString(opencv_error, "Unknown C++ exception from OpenCV code"); \
+    return 0; \
 }
 
 using namespace cv;