CPPCNN

A tiny framework of convolutional neural networks with C++ implementation. You can add arbitrary number of convolutional layers, max pooling layers and hidden layers to construct your own convolutional neural networks.

This framework contains a sub neural network framework which is multi-layer neural network, you can also use it as CNNs to construct your own multi-layer neural netowrk.

This project also implemented Momentum SGD and Adam Optimizer in Multi-layer Neural Networks part and can be enabled by functions.

Build

mkdir build && cd build
cmake ..
make on macOS OR open solution if you are using windows

Tested on Windows or macOS, but should also work on linux systems.

Test and verification

This tiny frame work has been tested on MNIST(handwritten digits) dataset by LeCun.

1. make sure there are 4 files named train-images.idx3-ubyte train-labels.idx1-ubyte t10k-images.idx3-ubyte t10k-labels.idx1-ubyte in the data/mnist path. Dataset can be downloaded from here.
2. after build, if you are on macOS, run ./cppcnn in build folder, then it will load MNIST dataset and after 1-3 hours on CPU, it will give the test results.

Performance of Multi-layer Neural Networks

Get 95% accuracy by 5 epoch, with hyperparameters:

• learning rate: 1.0
• hidden layers: one hidden layer with 256 units
• mini batch size: 256
• momentum SGD: disabled
• adam optimizer: disabled

Performance of Convolutional Neural Networks

Get 98% accuracy by 3 epoch, with hyperparameters:

• learning rate: 0.005
• convolution layers: one convolution layer with 8 convolution filters, size 3, stride 1, no padding
• pooling layers: one max pooling layer with size 2, stride 2
• hidden layers: two hidden layer with 32 and 16 units
• mini batch size: 1
• momentum SGD: disabled
• adam optimizer: disabled

TO DO

• Fix pooling layer bug for odd case.
• Implement Momentum SGD and Adam Optimizer in CNN class.
• Provide average pooling layer.
• Provide GPU acceleration.