VLB: VLFeat Local Features Benchmark

A framework for local feature evaluation. Reimplementation of the VLBenchmarks project. Currenlty work in progress so it has more than few rough edges.

MATLAB implementation: Karel Lenc
Python implementation: Xu Zhang

Getting Started with MATLAB implementation

Setup matlab mex environment, before starting to setup vlb.

To setup the VLBenchmarks, run from the vlb path:

run ./matlab/vlb_setup.m
run ./matlab/vlb_compile.m

where one needs to compile the package only while running for the first time.

For example usage, see the prepared examples:

• detbench.m - Detector benchmarks and results visualsiation
• descbench.m - Descriptor benchmarks

Basic Usage

The entry function is vlb which supports the following commands:

FEATSNAME = vlb('detect', IMDBNAME, DETNAME)
Detects features of all images of a IMDBNAME image database. Features stored ./data/features/IMDBNAME/DETNAME/ as csv files. Additionally one can also extract the detected patches with the extract command.

FEATSNAME = vlb('describe', IMDBNAME, FEATSNAME, DESCNAME)
Computes descriptors of all features detected by FEATSNAME of IMDBNAME image database. Features stored in ./data/features/IMDBNAME/FEATSNAME/DESCNAME/ as csv files.

RES = vlb('detrep', IMDBNAME, FEATSNAME)
RES = vlb('dematch', IMDBNAME, FEATSNAME)
RES = vlb('descmatch', IMDBNAME, FEATSNAME)
Evaluates the detector repeatabiliy, detector matching score or a descriptor matching score of features FEATSNAME in the selected dataset. Returns a table with results, which is additionally stored in ./data/scores/BENCH/IMDBNAME/FEATSNAME as a csv file.

Custom Features

For custom features, you can either add your own wrapper to matlab/+features/+det or matlab/+features/+desc, depending whether the input is an image or patches/detected keypoints. Afterwards, you can use the vlb interface directly.

However, you can also compute the features outside of MATLAB and store them as CSV files. To get the list of image paths and target feature paths in format: IMAGEPATH;TARGET_FRAMESPATH;TARGET_DESCSPATH you can run:

vlb imagelist IMDBNAME FEATSNAME

Typically, this would create a file in data/IMDBNAME-FEATSNAME.csv

The format of the CSV files is one descriptor/frame per line. The frames or one-indexed (center of the first image pixel has a coordinate [1, 1]) and in format of vl_plotframe ([c, r] for a point, [c, r, s] for a disc, [c, r, s, rot] for oriented disc, [c, r, S11, S12, S22] for ellipse, [c, r, A11, A12, A21, A22] for oriented ellipse/affine frame).

Directory structure

data/features/DATASET/FEATURES Compputed local features in csv format (see vlb detect and vlb describe) data/patches/DATASET/FEATURES Extracted patches as png images (see vlb extract) data/scores/BENCHMARK/DATASET/FEATURES Computed benchmark scores, stored as .csv tables datasets Downloaded datasets matlab MATLAB source code matlab/+dset Implemented datasets (VGG-Aff, EdgeFoci, WebCam, Hsequences...).
matlab/+features/+det Implemented detector wrappers.
matlab/+features/+desc Implemented descriptor wrappers. Please note that some descriptors accept detected frames, some need extracted patches.

Furthermore, you can extract the features outside of this framework in order to evaluate them. Please extract e.g. vlsift features and follow the naming conventions.

Compile Conflicts

mex command may be recognized as mex command in texlive. Make sure that the matlab/bin path is added to system PATH before the directory of mex in texlive.

Running the tests

To run the tests, call: vlb_test.

Python Interface

Requirement

Make a complete clone operation to pull the submodule.

git clone --recursive git@github.com:lenck/vlb.git

We recommend to use conda to install all the requirements all at once.

conda env create -f ./python/conda/environment.yml
source activate vlb
pip install nmslib

Test the code

Test repeatability benchmark

python ./python/test/test_rep_bench.py

Test matching score benchmark

Download vlsift_load_matlab.zip and extract it to ./data/features/vggh/. Then run

python ./python/test/test_ms_bench.py

Test image retrieval benchmark

python ./python/test/test_retrieval_bench.py

Test wide baseline matching benchmark

python ./python/test/test_W1BS_Bench.py

Test feature extraction

python ./python/test/test_feature_extraction.py

Test draw feature

python ./python/test/draw_frame.py