How to extract features from Bounding box?
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Hi, I have bounding box for each training image. I need MATLAB code to extract features from each bounding box. I don't want to extract features from entire image but only from bounding box. Could someone provide me the required code?
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Image Analyst
on 3 May 2014
See my image segmentation tutorial: http://www.mathworks.com/matlabcentral/fileexchange/?term=authorid%3A31862.
The specifics depend on what features you want to extract. I show examples of area, perimeter, bounding box, etc. In short, extract your bounding box with imcrop, then process it to get a binary image and then label and call regionprops().
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Image Analyst
on 4 May 2014
Looks like a car was already detected in each image. How did you get the yellow boxes otherwise? What information do you need to carry out your task? What is your task? You could measure lots of things in the box, like color, number or length of edges, etc. But more important is what do you need? I mean really need . I mean, why measure things that you don't need to? So let's just measure what you need. To do that we need to know your use case. Let's say that I measured 30 things in the box. Okay, now what? What are you going to do with those 30 measurements in that feature vector (which is what the list of 30 measurements is called)? Just because the detected car box is different sizes doesn't mean that the feature vector has different dimensions or different lengths. It could be 30 measurements long for every single box.
Dima Lisin
on 4 May 2014
What sort of features? If you mean interest points and local descriptors, then detectHarrisFeatures(), detectFASTFeatures(), detectSURFFeatures(), and detectMSERFeatures() all let you specify an ROI. These functions are in the Computer Vision System Toolbox.
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