Initialized repo

Author: Guillaume Lagrange

.gitignore

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+# vscode stuff
+.vscode/
+
+# python stuff
+__pycache__/
+
+# don't commit heavy data
+data/
+
+# cpp
+build/

README.md

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 # pytorch-cpp
-Just messing around with PyTorch 1.0 (currently pre-release 1.0rc1) and their new C++ API Libtorch.
+In this repo I experiment with PyTorch 1.0 and their new JIT compiler, as well as their C++ API Libtorch.
+
+Currently, the repo contains a VGG16 based network implementation in PyTorch for CIFAR-10 classification (based on my [previous experiment](https://github.com/laggui/NN_compress)), and the C++ source for inference.
+
+## pytorch/
+This subdirectory includes the network's [architecture definition](pytorch/vgg.py), the [training script](pytorch/train.py), the [test script](pytorch/test.py) on the CIFAR-10 dataset, a [prediction script](pytorch/predict.py) for inference and, most importantly, the [script to convert the model to Torch Script](pytorch/to_torch_script.py).
+
+## libtorch/
+This is where you'll find the source for the network's inference in C++. In [predict.cpp](libtorch/predict.cpp), we load the Torch Script module generated in PyTorch, read the input image and pre-process it in order to feed it to our network for inference.
+
+## Example Usage
+
+### PyTorch Predict
+
+```sh
+pytorch$ python predict.py pytorch --model=../data/VGG16model.pth --image=../data/dog.png
+==> Building model...
+==> Loading PyTorch model...
+Predicted: dog | 10.056212425231934
+Time: 0.06844925880432129 seconds
+```
+
+### Libtorch
+Before running our prediction, we need to compile the source. In your `libtorch` directory, create a build directory and compile+build the application from source.
+
+```sh
+libtorch$ mkdir build 
+libtorch$ cd build
+libtorch/build$ cmake -DCMAKE_PREFIX_PATH=/path/to/libtorch ..
+-- The C compiler identification is GNU 5.4.0
+-- The CXX compiler identification is GNU 5.4.0
+-- Check for working C compiler: /usr/bin/cc
+-- Check for working C compiler: /usr/bin/cc -- works
+-- Detecting C compiler ABI info
+.
+.
+.
+-- Configuring done
+-- Generating done
+-- Build files have been written to: libtorch/build
+libtorch/build$ make
+Scanning dependencies of target vgg-predict
+[ 50%] Building CXX object CMakeFiles/vgg-predict.dir/predict.cpp.o
+[100%] Linking CXX executable vgg-predict
+[100%] Built target vgg-predict  
+```
+
+You're now ready to run the application.
+
+```sh
+libtorch/build$ ./vgg-predict ../../data/VGG16model.pth ../../data/dog.png
+Model loaded
+Moving model to GPU
+Predicted: dog | 10.0562
+Time: 0.009481 seconds
+```
+
+
+