  This paper proposes ReBNet, an end-to-end framework for training
reconfigurable binary neural networks on software and developing efficient
accelerators for execution on FPGA. Binary neural networks offer an intriguing
opportunity for deploying large-scale deep learning models on
resource-constrained devices. Binarization reduces the memory footprint and
replaces the power-hungry matrix-multiplication with light-weight XnorPopcount
operations. However, binary networks suffer from a degraded accuracy compared
to their fixed-point counterparts. We show that the state-of-the-art methods
for optimizing binary networks accuracy, significantly increase the
implementation cost and complexity. To compensate for the degraded accuracy
while adhering to the simplicity of binary networks, we devise the first
reconfigurable scheme that can adjust the classification accuracy based on the
application. Our proposition improves the classification accuracy by
representing features with multiple levels of residual binarization. Unlike
previous methods, our approach does not exacerbate the area cost of the
hardware accelerator. Instead, it provides a tradeoff between throughput and
accuracy while the area overhead of multi-level binarization is negligible.
