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Hi,

I'm extracting SURF descriptors from an image using the following simple lines:

Ptr<DescriptorExtractor> descriptor = DescriptorExtractor::create("SURF");
    descriptor->compute(im1, kp, desc1);

Now, when I "watch" the variable desc1.data, it contains integer values in the range 0 to 255.

However, when I investigate the values using the code:

for (int j=0;j<desc1.cols; j++){
            float a=desc1.at<float>(0,j);

it contains values between -1 and 1. How is that possible? SURF shouldn't return integer values like SURF?

Thanks in advance!

Hi,

I'm extracting SURF descriptors from an image using the following simple lines:

Ptr<DescriptorExtractor> descriptor = DescriptorExtractor::create("SURF");
    descriptor->compute(im1, kp, desc1);

Now, when I "watch" the variable desc1.data, it contains integer values in the range 0 to 255.

However, when I investigate the values using the code:

for (int j=0;j<desc1.cols; j++){
            float a=desc1.at<float>(0,j);

it contains values between -1 and 1. How is that possible? SURF shouldn't return integer values like SURF?SIFT?

Thanks in advance!