Caffe has command line, Python, and MATLAB interfaces for day-to-day usage, interfacing with research code, and rapid prototyping. While Caffe is a C++ library at heart and it exposes a modular interface for development, not every occasion calls for custom compilation. The cmdcaffe, pycaffe, and matcaffe interfaces are here for you.
The command line interface – cmdcaffe – is the
caffe tool for model training, scoring, and diagnostics. Run
caffe without any arguments for help. This tool and others are found in caffe/build/tools. (The following example calls require completing the LeNet / MNIST example first.)
caffe train learns models from scratch, resumes learning from saved snapshots, and fine-tunes models to new data and tasks. All training requires a solver configuration through the
-solver solver.prototxt argument. Resuming requires the
-snapshot model_iter_1000.solverstate argument to load the solver snapshot. Fine-tuning requires the
-weights model.caffemodel argument for the model initialization.
# train LeNet caffe train -solver examples/mnist/lenet_solver.prototxt # train on GPU 2 caffe train -solver examples/mnist/lenet_solver.prototxt -gpu 2 # resume training from the half-way point snapshot caffe train -solver examples/mnist/lenet_solver.prototxt -snapshot examples/mnist/lenet_iter_5000.solverstate
For a full example of fine-tuning, see examples/finetuning_on_flickr_style, but the training call alone is
# fine-tune CaffeNet model weights for style recognition caffe train -solver examples/finetuning_on_flickr_style/solver.prototxt -weights models/bvlc_reference_caffenet/bvlc_reference_caffenet.caffemodel
caffe test scores models by running them in the test phase and reports the net output as its score. The net architecture must be properly defined to output an accuracy measure or loss as its output. The per-batch score is reported and then the grand average is reported last.
# # score the learned LeNet model on the validation set as defined in the model architeture lenet_train_test.prototxt caffe test -model examples/mnist/lenet_train_test.prototxt -weights examples/mnist/lenet_iter_10000 -gpu 0 -iterations 100
caffe time benchmarks model execution layer-by-layer through timing and synchronization. This is useful to check system performance and measure relative execution times for models.
# (These example calls require you complete the LeNet / MNIST example first.) # time LeNet training on CPU for 10 iterations caffe time -model examples/mnist/lenet_train_test.prototxt -iterations 10 # time a model architecture with the given weights on the first GPU for 10 iterations # time LeNet training on GPU for the default 50 iterations caffe time -model examples/mnist/lenet_train_test.prototxt -gpu 0
caffe device_query reports GPU details for reference and checking device ordinals for running on a given device in multi-GPU machines.
# query the first device caffe device_query -gpu 0
The Python interface – pycaffe – is the
caffe module and its scripts in caffe/python.
import caffe to load models, do forward and backward, handle IO, visualize networks, and even instrument model solving. All model data, derivatives, and parameters are exposed for reading and writing.
caffe.Netis the central interface for loading, configuring, and running models.
caffe.Detectorprovide convenience interfaces for common tasks.
caffe.SGDSolverexposes the solving interface.
caffe.iohandles input / output with preprocessing and protocol buffers.
caffe.drawvisualizes network architectures.
Tutorial IPython notebooks are found in caffe/examples: do
ipython notebook caffe/examples to try them. For developer reference docstrings can be found throughout the code.
Compile pycaffe by
make pycaffe. The module dir caffe/python/caffe should be installed in your PYTHONPATH for
The MATLAB interface – matcaffe – is the
caffe mex and its helper m-files in caffe/matlab. Load models, do forward and backward, extract output and read-only model weights, and load the binaryproto format mean as a matrix.
A MATLAB demo is in caffe/matlab/caffe/matcaffe_demo.m
Note that MATLAB matrices and memory are in column-major layout counter to Caffe’s row-major layout! Double-check your work accordingly.
Compile matcaffe by