<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto"><div>Nothing. It was chosen arbitrarily based on a test set of images<br><br>Sent from my iPhone</div><div><br>On Apr 26, 2013, at 10:35 AM, Ricky Huang <<a href="mailto:rhuang.work@gmail.com">rhuang.work@gmail.com</a>> wrote:<br><br></div><blockquote type="cite"><div><meta http-equiv="Content-Type" content="text/html charset=iso-8859-1"><div>Thanks for the answer, Evan.</div><div><br></div><div>On the website, there's a threshold value (of 0.4 for MH algorithm), how is that determined? What makes 0.4 a cut off between similar or dissimilar?</div><div><br></div><div><br></div><br><div><div>On Apr 25, 2013, at 11:03 AM, Evan Klinger <<a href="mailto:eklinger@phash.org">eklinger@phash.org</a>> wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div dir="ltr"><div>Ricky,<br></div>You cannot read too much into the hamming distance values. Like you said the lower the number the higher likelihood of it being the same or similar image. You cannot determine a percentage difference from the hamming distance nor derive any meaningful contextual information from it.<br>
<br>Thanks<br>Evan<br></div><div class="gmail_extra"><br><br><div class="gmail_quote">On Wed, Apr 24, 2013 at 6:58 PM, Ricky Huang <span dir="ltr"><<a href="mailto:rhuang.work@gmail.com" target="_blank">rhuang.work@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div style="word-wrap:break-word">Hello pHash team,<div><br></div><div>I am wondering how does one read the return value of the hamming distance function. While I understand that the smaller the value, the more similar the two hashes (consequently, the images), is there a rule of thumb on the interpretation of the actual value. E.g., "if hamming distance > 0.50, do not bother with the image".</div>
<div><br></div><div>Also on the same topic, what does the ph_hammingdistance2() value actually mean? E.g., "hamming distance of 0.4 means the hashes are 40% dissimilar", etc.</div><div><br></div><div><br></div>
<div>Thanks!<br>
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