How to plot Hog features in the image

Hey

I am trying to feature extraction from an image for some certain points. First time I am using HogFeatureextraction. When I plot the features and valid points, I am getting result not on the certain points. I will use these features for training later on. For example, I have points on the straight line. Should not my features on where my certain points on the line. I am a little bit confused about concept of it. I used [features,validPoints] = extractHOGFeatures(I,points). x and y are my 10 positions in the image. In this case how is feature extraction working?

[features,validPoints] = extractHOGFeatures(I,[x,y]); figure; imshow(I); hold on; plot(features, 'ro'); plot(validPoints,'go');

Thank you

Answer 1

[Birju Patel]

Hi,

The following example, will visualize the HOG features at a set of points:

     I2 = imread('gantrycrane.png');
     corners   = detectFASTFeatures(rgb2gray(I2));
     strongest = selectStrongest(corners, 3);
     [hog2, validPoints, ptVis] = extractHOGFeatures(I2, strongest);
     figure;
     imshow(I2); hold on;
     plot(ptVis, 'Color','green');

HTH