Keras Image Classification
Classifies an image as containing either a dog or a cat (using Kaggle's public dataset), but could easily be extended to other image classification problems.
To run these scripts/notebooks, you must have keras, numpy, scipy, and h5py installed, and enabling GPU acceleration is highly recommended if that's an option.
img_clf.py
After playing around with hyperparameters a bit, this reaches around 96-98% accuracy on the validation data, and when tested on Kaggle's hidden test data achieved a log loss score around 0.18.
Most of the code / strategy here was based on this Keras tutorial.
Pre-trained VGG16 model weights can be downloaded here.
The data directory structure I used was:
- project
- data
- train
- dogs
- cats
- validation
- dogs
- cats
- test
- test
- train
- data
cats_n_dogs.ipynb:
This produced a slightly better score (.161 log loss on kaggle test set). The better score most likely comes from having larger images and ensembling a few models, despite the fact there's no image augmentation in the notebook.
Might run into memory errors because of the large image dimensions -- if so reducing the number of folds and saving the model weights rather than keeping the models in memory should do the trick. The notebook uses a slightly flatter directory structure, with the validation split happening after the images are loaded:
- project
- data
- train
- dogs
- cats
- test
- test
- train
- data
cats_n_dogs_BN.ipynb:
This produced the best score (0.069 loss without any ensembling). The notebook incorporates some of the techniques from Jeremy Howard's deep learning class , with the inclusion of batch normalization being the biggest factor. I also added extra layers of augmentation to the prediction script, which greatly improved performance.
Pre-trained model weights for VGG16 w/ batch normalization can be downloaded here.
The VGG16BN class is defined in vgg_bn.py, and the data directory structure used was:
- project
- data
- train
- dogs
- cats
- validation
- dogs
- cats
- test
- test
- train
- data