Merge remote-tracking branch 'origin/2.4'

Conflicts:
	doc/tutorials/features2d/feature_detection/feature_detection.rst
	modules/bioinspired/doc/retina/index.rst
	modules/core/include/opencv2/core/core.hpp
	modules/core/include/opencv2/core/mat.hpp
	modules/core/include/opencv2/core/operations.hpp
	modules/core/src/stat.cpp
	modules/features2d/include/opencv2/features2d/features2d.hpp
	modules/imgproc/src/filter.cpp
	modules/legacy/src/dpstereo.cpp
	modules/nonfree/src/surf.ocl.cpp
	modules/ocl/doc/image_processing.rst
	modules/ocl/doc/object_detection.rst
	modules/ocl/include/opencv2/ocl/ocl.hpp
	modules/ocl/include/opencv2/ocl/private/util.hpp
	modules/ocl/src/arithm.cpp
	modules/ocl/src/canny.cpp
	modules/ocl/src/filtering.cpp
	modules/ocl/src/imgproc.cpp
	modules/ocl/src/initialization.cpp
	modules/ocl/src/matrix_operations.cpp
	modules/ocl/src/pyrdown.cpp
	modules/ocl/src/pyrup.cpp
	modules/ocl/src/split_merge.cpp
	modules/ocl/test/test_objdetect.cpp
	modules/ocl/test/utility.hpp

modules/core/include/opencv2/core/core_c.h

@@ -1144,7 +1144,7 @@ CVAPI(void)   cvSetRemove( CvSet* set_header, int index );
    NULL is returned */
 CV_INLINE CvSetElem* cvGetSetElem( const CvSet* set_header, int idx )
 {
-    CvSetElem* elem = (CvSetElem*)cvGetSeqElem( (CvSeq*)set_header, idx );
+    CvSetElem* elem = (CvSetElem*)(void *)cvGetSeqElem( (CvSeq*)set_header, idx );
     return elem && CV_IS_SET_ELEM( elem ) ? elem : 0;
 }
 

modules/core/include/opencv2/core/mat.inl.hpp

@@ -1734,13 +1734,13 @@ const _Tp& SparseMat::value(const Node* n) const
 inline
 SparseMat::Node* SparseMat::node(size_t nidx)
 {
-    return (Node*)&hdr->pool[nidx];
+    return (Node*)(void*)&hdr->pool[nidx];
 }
 
 inline
 const SparseMat::Node* SparseMat::node(size_t nidx) const
 {
-    return (const Node*)&hdr->pool[nidx];
+    return (const Node*)(const void*)&hdr->pool[nidx];
 }
 
 inline
@@ -2488,7 +2488,7 @@ const _Tp& SparseMatConstIterator::value() const
 inline
 const SparseMat::Node* SparseMatConstIterator::node() const
 {
-    return (ptr && m && m->hdr) ? (const SparseMat::Node*)(ptr - m->hdr->valueOffset) : 0;
+    return (ptr && m && m->hdr) ? (const SparseMat::Node*)(const void*)(ptr - m->hdr->valueOffset) : 0;
 }
 
 inline

modules/core/include/opencv2/core/persistence.hpp

@@ -861,8 +861,8 @@ inline FileNode::operator String() const { String value; read(*this, value, valu
 inline FileNodeIterator FileNode::begin() const { return FileNodeIterator(fs, node); }
 inline FileNodeIterator FileNode::end() const   { return FileNodeIterator(fs, node, size()); }
 inline void FileNode::readRaw( const String& fmt, uchar* vec, size_t len ) const { begin().readRaw( fmt, vec, len ); }
-inline FileNode FileNodeIterator::operator *() const  { return FileNode(fs, (const CvFileNode*)reader.ptr); }
-inline FileNode FileNodeIterator::operator ->() const { return FileNode(fs, (const CvFileNode*)reader.ptr); }
+inline FileNode FileNodeIterator::operator *() const  { return FileNode(fs, (const CvFileNode*)(const void*)reader.ptr); }
+inline FileNode FileNodeIterator::operator ->() const { return FileNode(fs, (const CvFileNode*)(const void*)reader.ptr); }
 inline String::String(const FileNode& fn): cstr_(0), len_(0) { read(fn, *this, *this); }
 
 } // cv

modules/core/include/opencv2/core/types_c.h

@@ -523,11 +523,11 @@ CV_INLINE  double  cvmGet( const CvMat* mat, int row, int col )
             (unsigned)col < (unsigned)mat->cols );
 
     if( type == CV_32FC1 )
-        return ((float*)(mat->data.ptr + (size_t)mat->step*row))[col];
+        return ((float*)(void*)(mat->data.ptr + (size_t)mat->step*row))[col];
     else
     {
         assert( type == CV_64FC1 );
-        return ((double*)(mat->data.ptr + (size_t)mat->step*row))[col];
+        return ((double*)(void*)(mat->data.ptr + (size_t)mat->step*row))[col];
     }
 }
 
@@ -540,11 +540,11 @@ CV_INLINE  void  cvmSet( CvMat* mat, int row, int col, double value )
             (unsigned)col < (unsigned)mat->cols );
 
     if( type == CV_32FC1 )
-        ((float*)(mat->data.ptr + (size_t)mat->step*row))[col] = (float)value;
+        ((float*)(void*)(mat->data.ptr + (size_t)mat->step*row))[col] = (float)value;
     else
     {
         assert( type == CV_64FC1 );
-        ((double*)(mat->data.ptr + (size_t)mat->step*row))[col] = (double)value;
+        ((double*)(void*)(mat->data.ptr + (size_t)mat->step*row))[col] = (double)value;
     }
 }
 

modules/core/include/opencv2/core/utility.hpp

@@ -238,6 +238,7 @@ template<typename _Tp> static inline _Tp* alignPtr(_Tp* ptr, int n=(int)sizeof(_
 */
 static inline size_t alignSize(size_t sz, int n)
 {
+    CV_DbgAssert((n & (n - 1)) == 0); // n is a power of 2
     return (sz + n-1) & -n;
 }