sppnet-pytorch

SPP layer could be added in CNN model between convolutional layer and fully-connected lay, so that you can input multi-size images into your CNN model. The function spatial_pyramid_pool() in file spp_layer.py is independent. It could be added in your own models. See this:Spatial Pyramid Pooling in Deep Convolutional Networks for Visual Recognition

SPP_Layer.py provides a torch.nn.Module of spp_layer which can be inserted into any models very easily.