Emgu CV Library Documentation
PyrDown Method
NamespacesEmgu.CVIImagePyrDown()()()

www.emgu.com/wiki
The function PyrDown performs downsampling step of Gaussian pyramid decomposition. First it convolves this image with the specified filter and then downsamples the image by rejecting even rows and columns.
Declaration Syntax
C#Visual BasicVisual C++
IImage PyrDown()
Function PyrDown As IImage
IImage^ PyrDown()
Return Value
The downsampled image

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