MMFeat

Multi-modal features toolkit in Python, developed at the University of Cambridge Computer Laboratory. The aim of this toolkit is to make it easier for researchers to use multi-modal features. Both image and sound (i.e., visual and auditory representations) are supported.

The following models are currently available:

1. CNN: Convolutional neural network representations for images
2. BoVW: Bag-of-visual-words for images, using DSIFT local descriptors
3. BoAW: Bag-of-audio-words for sound files, using MFCC local descriptors

Getting started

The following dependencies need to be installed: numpy, scipy, scikit-learn and yaml. If you want to use the CNN model, you will also need to install Caffe. For BoAW you will need to install librosa as well.

Installing the main dependencies on Ubuntu:

sudo apt-get install build-essential python-dev python-setuptools \
                python-numpy python-scipy python-sklearn python-yaml

Tools

The toolkit comes with two tools that do not require any knowledge of Python and that can be run from the command-line.

miner.py

For mining images or sound files. Before you can use the miner you need to acquire API keys from Google, Bing, FreeSound or Flickr and set them in miner.yaml (see miner-example.yaml for an example). The query_file argument should point to a file that contains a list of queries, one query per line. Usage:

miner.py [-h] [-n NUM_FILES]
                {bing,google,freesound,flickr} query_file data_dir

Examples:

# Get 10 images per query term from Bing and store in a data directory
python miner.py -n 10 bing list_of_queries.txt ./img_data_dir
# Get 100 sound files per query term from FreeSound and store in a data directory
python miner.py -n 100 freesound list_of_queries.txt ./sound_data_dir

extract.py

For extracting representations from a data directory. The data directory needs to contain an index file (index.pkl) that the is automatically generated by the miner, or that you can manually construct. Usage:

extract.py [-h] [-gpu] [-k K] [-c CENTROIDS] [-o {pickle,json,csv}]
                  [-s SAMPLE_FILES] [-m {vgg,alexnet}] [-v]
                  {boaw,bovw,cnn} data_dir out_file

Examples:

# Extract BoVW representations with k=100, sampling 10% for clustering, and store as a Python pickle.
python extract.py -k 100 -s 0.1 bovw ./img_data_dir ./output_vectors.pkl
# Extract CNN representations, using an AlexNet on a GPU, and store as a JSON file.
python extract.py -gpu -o json cnn ./img_data_dir ./output_vectors.json
# Extract BoAW representation with k=300, sampling 50% for clustering, and store as a CSV file.
python extract.py -k 300 -s 0.5 -o csv boaw ./sound_data_dir ./output_vectors.csv

To extract layers from the CNN you need to tell the toolkit where it can find Caffe. For example (run this, or simply add to your ~/.bashrc):

export CAFFE_ROOT_PATH="/usr/local/caffe/"

Demos

1. Similarity and relatedness (1-simrel)

The demo downloads images from either Google or Bing and creates BoVW or CNN representations. It then evaluates similarity and relatedness (i.e., Spearman correlation with human similarity ratings) on the well-known MEN and SimLex-999 datasets. See e.g. Learning Image Embeddings using Convolutional Neural Networks for Improved Multi-Modal Semantics

2. ESP Game dataset (2-esp)

The demo downloads the ESP Game dataset sample and extracts it. It then builds an index from the label lookup and obtains BoAW or CNN representations for the thumbnail images. The representations are stored in a file for later use.

3. Matlab interfacing (3-matlab)

A simple demo to show that you can get local descriptors from Matlab and load them. This means you can use VLFeat or other libraries for getting descriptors (for instance, PHOW) as well.

4. Music instrument clustering (4-instruments)

The demo downloads sound files for 8 instruments of two classes and obtains auditory representations. It then clusters the representations and reports the outcomes. See Multi- and Cross-Modal Semantics Beyond Vision: Grounding in Auditory Perception

5. Image dispersion scores (5-dispersion)

The demo downloads images for "elephant" and "happiness" and calculates the image dispersion scores of these concepts. See Improving Multi-Modal Representations Using Image Dispersion: Why Less is Sometimes More.

6. Image search plot (6-searchplot)

A simple plotting demo of images returned by various search engines. Requires matplotlib.