I am presented with a number inside an image that I believe is generated by a captcha generator (securimage/phpcaptcha). I don't actually need to read the number represented in the image, but I do need to know when the magnitude changes. So if the current image contains "0.00005", I need to count the digits to find that it has six, so that when I get an image containing "0.09" and see that it contains only 3 digits, I can take the necessary action.

Here is an example image. I first tried using OCR (tesseract/gocr,/ocrad), but the captcha makes that too hard without first doing pre-processing, which might be a harder problem to solve (the text changes color and the background noise dots are randomly colored). So after doing some research it looks like Blob_detection is what I need to do and that it sounds like it might be an easier problem to solve. Except I can't find anybody doing anything similar in Perl. The only thing I can find is contained in much larger frameworks, like OpenCV or Matlab, etc., which would require using a different language and calling system on an external program.

Has something like this been done before in Perl?

In reply to Image processing - count number of blobs by Anonymous Monk

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