Thanks! I'll look into alternative ways of producing features. -Lisa On Monday, July 8, 2013 6:28:52 AM UTC-4, Stefan van der Walt wrote:
Hi Lisa
Interestingly, Adam Wisniewski was working on this one-class classification problem at the recent SciPy2013 sprint. Olivier Grisel and Nelle Varoquaux from the sklearn team were able to give us some helpful advice, and it might be worth getting in touch with them as well.
On Wed, Jul 3, 2013 at 9:10 PM, Lisa Torrey <lisa....@gmail.com<javascript:>> wrote:
- I have much less data. (Just 77 positives and 78 negatives, compared to Dalal's 1239 and 12180.)
You'll probably have to do some kind of cross-validation.
- My images aren't all the same size, like the pedestrian images are. (I'm not sure if this would matter?)
Perhaps investigate multi-scale texture features, such as the wavelet coefficients (see http://www.pybytes.com/pywavelets/ ; even simple statistics might suffice).
- My images are much higher resolution. (I've been downscaling them by a factor of 8, but the feature vectors are still enormous.)
You'd want to extract some features that help the classifier, e.g. daisy (http://scikit-image.org/docs/dev/auto_examples/plot_daisy.html), texture features via grey-level co-occurrence matrices, or haralick features (we don't yet have those in skimage, although they are available in Luis Coelho's Mahotas).
Regards Stéfan