It seems your code cannot run well, bugs exist

[wangchuan]

I am running your matlab code but encountered problems. I have well generated the knnRecognizer and svmRecognizer, however, when I test the code using

result = decaptcha('./Captcha_qyaixdweaz.jpg', true, 'knn', knnRecognizer);

It came out that, in line 123 of the file ppImg.m, variable Ibox is a 4x1 vector, so length(Ibox) is 4, and Ibox(1:2, count) will exceed the matrix dimensions.

Could you check it?