title: Transform hog descriptor from Matlab to Java OpenCV
body: <p>I have some codes which written in Matlab and I want to convert them into Java OpenCV to be suitable for Android devices. In Matlab code I use <code>extractHOGFeatures</code> which is a function in the computer vision toolbox to extract the hog vector. While I use HOGDescriptor class in OpenCV to extract the hog vector. </p>
  
  <p>However, the output vectors from both are different from each other. I try to understand the problem and what I found are: </p>
  
  <p>the block size, the cell size, the block overlap and the number of bins are the same in both vectors that obtained from <code>extractHOGFeatures (Matlab)</code> and HOGDescriptor class(OpenCV). But the size of sliding window in OpenCV is 64*128. While in Matlab I can not determine what is the default size of the sliding window even when I access the documentary of the function. </p>
  
  <p>Can anybody help me how I can obtain the same output? </p>
  
  <p>I need OpenCV modification not Matlab since in my project situation I can not change the Matlab code</p>