Emgu CV Library Documentation
cvReduce Method (src, dst, type)
NamespacesEmgu.CVCvInvokecvReduce(IntPtr, IntPtr, REDUCE_TYPE)

www.emgu.com/wiki
Reduces matrix to a vector by treating the matrix rows/columns as a set of 1D vectors and performing the specified operation on the vectors until a single row/column is obtained.
Declaration Syntax
C#Visual BasicVisual C++
public static void cvReduce(
	IntPtr src,
	IntPtr dst,
	REDUCE_TYPE type
)
Public Shared Sub cvReduce ( _
	src As IntPtr, _
	dst As IntPtr, _
	type As REDUCE_TYPE _
)
public:
static void cvReduce(
	IntPtr src, 
	IntPtr dst, 
	REDUCE_TYPE type
)
Parameters
src (IntPtr)
The input matrix
dst (IntPtr)
The output single-row/single-column vector that accumulates somehow all the matrix rows/columns
type (REDUCE_TYPE)
The reduction operation type
Remarks
The function can be used to compute horizontal and vertical projections of an raster image. In case of CV_REDUCE_SUM and CV_REDUCE_AVG the output may have a larger element bit-depth to preserve accuracy. And multi-channel arrays are also supported in these two reduction modes

Assembly: Emgu.CV (Module: Emgu.CV) Version: 1.3.0.0 (1.3.0.0)