EXTRACTION_MATCHING.md

Quick start: DELF extraction and matching

To illustrate DELF usage, please download the Oxford buildings dataset. To follow these instructions closely, please download the dataset to the tensorflow/models/research/delf/delf/python/examples directory, as in the following commands:

# From tensorflow/models/research/delf/delf/python/examples/
mkdir data && cd data
wget http://www.robots.ox.ac.uk/~vgg/data/oxbuildings/oxbuild_images.tgz
mkdir oxford5k_images oxford5k_features
tar -xvzf oxbuild_images.tgz -C oxford5k_images/
cd ../
echo data/oxford5k_images/hertford_000056.jpg >> list_images.txt
echo data/oxford5k_images/oxford_000317.jpg >> list_images.txt

Also, you will need to download the trained DELF model:

# From tensorflow/models/research/delf/delf/python/examples/
mkdir parameters && cd parameters
wget http://download.tensorflow.org/models/delf_v1_20171026.tar.gz
tar -xvzf delf_v1_20171026.tar.gz

DELF feature extraction

Now that you have everything in place, running this command should extract DELF features for the images hertford_000056.jpg and oxford_000317.jpg:

# From tensorflow/models/research/delf/delf/python/examples/
python extract_features.py \
  --config_path delf_config_example.pbtxt \
  --list_images_path list_images.txt \
  --output_dir data/oxford5k_features

Image matching using DELF features

After feature extraction, run this command to perform feature matching between the images hertford_000056.jpg and oxford_000317.jpg:

python match_images.py \
  --image_1_path data/oxford5k_images/hertford_000056.jpg \
  --image_2_path data/oxford5k_images/oxford_000317.jpg \
  --features_1_path data/oxford5k_features/hertford_000056.delf \
  --features_2_path data/oxford5k_features/oxford_000317.delf \
  --output_image matched_images.png

The image matched_images.png is generated and should look similar to this one:

Troubleshooting

matplotlib

matplotlib may complain with a message such as no display name and no $DISPLAY environment variable. To fix this, one option is add the line backend : Agg to the file config/matplotlib/matplotlibrc. On this problem, see the discussion here.