On Mar 14, 10:59 am, "Daniel Fetchinson" <[EMAIL PROTECTED]> wrote: > > > Since you seem to know quite a bit about this topic, what is your > > > opinion on the apparently 'generic' algorithm described here: > > >http://grail.cs.washington.edu/projects/query/? > > > So far it seems to me that it does what I'm asking for, it does even > > > more because it can take a hand drawn sample image and query the > > > database for similar photos. > > > > There is even a python implementation for it here: > > >http://members.tripod.com/~edcjones/pycode.html > > > > On the histogram method I agree that it won't work partly because of > > > what you say and partly because it is terribly slow since it's > > > comparing every single pixel. > > > I'm hardly the expert and can't answer authoritatively, but here's my 2c. > > > I can't comment as to the actual accuracy of the algorithm, since it > > will depend on your specific data set (set of photos). The algorithm is > > sensitive to spatial and luminance information (because of the YIQ > > colorspace), so there are simple ways in which it will fail. > > > The histogram method uses only color, but has a lot of numbers to > > compare. You may find the histogram method insensitive to spatial > > relations (a landscape with the mountain on the left and one with the > > mountain on the right) compared to the wavelet approach. > > > This is a relatively old paper, and I've seen other more recent image > > retrieval research using wavelets (some cases using only the > > high-frequency wavelets for "texture" information instead of the > > low-frequency ones used by this paper for "shape") and other information > > retrieval-related research using lossy compressed data as the features. > > If you have time, you may want to look at other research that cite this > > particular paper. > > > And just a thought: Instead of merely cutting off at m largest-wavelets, > > why not apply a quantization matrix to all the values? > > I'm not at all an expert, just started to look into image matching, so > I'm not quite sure what you mean. What's a quantization matrix in this > context?
Hello, I am also looking for the solution to the same problem. Could you let me know if you have found something useful so far? I appreciate your response. Thanks a lot. Sengly -- http://mail.python.org/mailman/listinfo/python-list
