common: add saveMVSInterface() in python

(cherry picked from commit 29d5afbc828bf30ddf4e6ae67998c067f182590d)

libs/Common/Types.h

@@ -1637,7 +1637,7 @@ class TDMatrix : public cv::Mat_<TYPE>
 	/// What is the elem stride of the matrix?
 	inline size_t elem_stride() const { ASSERT(dims == 2 && step[1] == sizeof(TYPE)); return step[1]; }
 	/// Compute the area of the 2D matrix
-	inline int area() const { ASSERT(dims == 2); return cols*rows; }
+	inline int area() const { ASSERT(dims == 0 || dims == 2); return cols*rows; }
 	/// Compute the memory size of this matrix (in bytes)
 	inline size_t memory_size() const { return cv::Mat::total() * cv::Mat::elemSize(); }
 

libs/MVS/DepthMap.cpp

@@ -1613,7 +1613,7 @@ bool MVS::LoadConfidenceMap(const String& fileName, ConfidenceMap& confMap)
 // export depth map as an image (dark - far depth, light - close depth)
 Image8U3 MVS::DepthMap2Image(const DepthMap& depthMap, Depth minDepth, Depth maxDepth)
 {
-	ASSERT(!depthMap.empty());
+	ASSERT(!depthMap.empty() && depthMap.isContinuous());
 	// find min and max values
 	if (minDepth == FLT_MAX && maxDepth == 0) {
 		cList<Depth,Depth,0> depths(0, depthMap.area());
@@ -1653,6 +1653,7 @@ bool MVS::ExportNormalMap(const String& fileName, const NormalMap& normalMap)
 {
 	if (normalMap.empty())
 		return false;
+	ASSERT(normalMap.isContinuous());
 	Image8U3 img(normalMap.size());
 	for (int i=normalMap.area(); --i >= 0; ) {
 		img[i] = [](const Normal& n) {
@@ -1673,6 +1674,7 @@ bool MVS::ExportNormalMap(const String& fileName, const NormalMap& normalMap)
 bool MVS::ExportConfidenceMap(const String& fileName, const ConfidenceMap& confMap)
 {
 	// find min and max values
+	ASSERT(confMap.empty() || confMap.isContinuous());
 	FloatArr confs(0, confMap.area());
 	for (int i=confMap.area(); --i >= 0; ) {
 		const float conf = confMap[i];

libs/MVS/Mesh.cpp

@@ -1461,6 +1461,8 @@ bool Mesh::LoadGLTF(const String& fileName, bool bBinary)
 // export the mesh to the given file
 bool Mesh::Save(const String& fileName, const cList<String>& comments, bool bBinary) const
 {
+	if (IsEmpty())
+		return false;
 	TD_TIMER_STARTD();
 	const String ext(Util::getFileExt(fileName).ToLower());
 	bool ret;

libs/MVS/PointCloud.cpp

@@ -360,7 +360,7 @@ bool PointCloud::Load(const String& fileName)
 // save the dense point cloud as PLY file
 bool PointCloud::Save(const String& fileName, bool bViews, bool bLegacyTypes, bool bBinary) const
 {
-	if (points.empty())
+	if (IsEmpty())
 		return false;
 	TD_TIMER_STARTD();