Object category recognition practical

A computer vision practical by the Oxford Visual Geometry group, authored by Andrea Vedaldi and Andrew Zisserman.

Start from doc/instructions.html.

Package contents

The package contains three exercises:

• exercise1.m: learns and test an image classifier on benchmark data
• exercise2.m: learns your own classifier
• exercise3.m: experiment with different image encoding methods

The computer vision algorithms are implemented by VLFeat. This package contains the following MATLAB functions:

• standardizeImage.m: Rescale an image to a standard size.
• computeFeatures.m: Compute dense SIFT keypoints and descriptors.
• encodeImage.m: Compute an image encoding: BoVW, VLAD, FV.
• removeSpatialInformation.m: Reduces and encoding using spatial subdivisions to a simple one.
• trainLinearSVM.m: Learn a linear support vector machine.
• displayRankedImagelist.m: Visualize a subset of a ranked list of images.
• getImageSet.m: Scan a directory for images.
• sampleLocalFeatures.m: Sample local features from a set of images in order to train and encoder.
• trainEncoder.m: Train a BoVW, VLAD, or FV encoder (i.e., learn visual word dictionary).

Appendix: Installing from scratch

1. From Bash, run ./extras/download.sh. This will download the PASCAL VOC data and extract a subsetof it.
2. From MATLAB, run addpath extras ; preprocess.m. This will download VLFeat and precompute the data for the practical.

Changes

• 2015a - Switches to VLFeat 0.9.20 (bugfixes).
• 2014a - Switches to VLFeat 0.9.18. Redone packaging and doc.
• 2013a - Switches to VLFeat 0.9.17. Adds VLAD and FV.
• 2012 - Minor cleanups.
• 2011 - Initial version.

License

Copyright (c) 2011-13 Andrea Vedaldi

Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated documentation
files (the "Software"), to deal in the Software without
restriction, including without limitation the rights to use, copy,
modify, merge, publish, distribute, sublicense, and/or sell copies
of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.