| | |
| | | #include "convolutional_layer.h" |
| | | #include <stdio.h> |
| | | |
| | | double convolution_activation(double x) |
| | | image get_convolutional_image(convolutional_layer layer) |
| | | { |
| | | return x*(x>0); |
| | | int h = (layer.h-1)/layer.stride + 1; |
| | | int w = (layer.w-1)/layer.stride + 1; |
| | | int c = layer.n; |
| | | return double_to_image(h,w,c,layer.output); |
| | | } |
| | | |
| | | double convolution_gradient(double x) |
| | | image get_convolutional_delta(convolutional_layer layer) |
| | | { |
| | | return (x>=0); |
| | | int h = (layer.h-1)/layer.stride + 1; |
| | | int w = (layer.w-1)/layer.stride + 1; |
| | | int c = layer.n; |
| | | return double_to_image(h,w,c,layer.delta); |
| | | } |
| | | |
| | | convolutional_layer *make_convolutional_layer(int h, int w, int c, int n, int size, int stride) |
| | | convolutional_layer *make_convolutional_layer(int h, int w, int c, int n, int size, int stride, ACTIVATION activator) |
| | | { |
| | | printf("Convolutional Layer: %d x %d x %d image, %d filters\n", h,w,c,n); |
| | | int i; |
| | | convolutional_layer *layer = calloc(1, sizeof(convolutional_layer)); |
| | | layer->h = h; |
| | | layer->w = w; |
| | | layer->c = c; |
| | | layer->n = n; |
| | | layer->stride = stride; |
| | | layer->kernels = calloc(n, sizeof(image)); |
| | | layer->kernel_updates = calloc(n, sizeof(image)); |
| | | layer->biases = calloc(n, sizeof(double)); |
| | | layer->bias_updates = calloc(n, sizeof(double)); |
| | | for(i = 0; i < n; ++i){ |
| | | layer->biases[i] = .005; |
| | | layer->kernels[i] = make_random_kernel(size, c); |
| | | layer->kernel_updates[i] = make_random_kernel(size, c); |
| | | } |
| | | layer->output = make_image((h-1)/stride+1, (w-1)/stride+1, n); |
| | | layer->output = calloc(((h-1)/stride+1) * ((w-1)/stride+1) * n, sizeof(double)); |
| | | layer->delta = calloc(((h-1)/stride+1) * ((w-1)/stride+1) * n, sizeof(double)); |
| | | layer->upsampled = make_image(h,w,n); |
| | | |
| | | if(activator == SIGMOID){ |
| | | layer->activation = sigmoid_activation; |
| | | layer->gradient = sigmoid_gradient; |
| | | }else if(activator == RELU){ |
| | | layer->activation = relu_activation; |
| | | layer->gradient = relu_gradient; |
| | | }else if(activator == IDENTITY){ |
| | | layer->activation = identity_activation; |
| | | layer->gradient = identity_gradient; |
| | | } |
| | | return layer; |
| | | } |
| | | |
| | | void run_convolutional_layer(const image input, const convolutional_layer layer) |
| | | void forward_convolutional_layer(const convolutional_layer layer, double *in) |
| | | { |
| | | int i; |
| | | image input = double_to_image(layer.h, layer.w, layer.c, in); |
| | | image output = get_convolutional_image(layer); |
| | | int i,j; |
| | | for(i = 0; i < layer.n; ++i){ |
| | | convolve(input, layer.kernels[i], layer.stride, i, layer.output); |
| | | convolve(input, layer.kernels[i], layer.stride, i, output); |
| | | } |
| | | for(i = 0; i < layer.output.h*layer.output.w*layer.output.c; ++i){ |
| | | layer.output.data[i] = convolution_activation(layer.output.data[i]); |
| | | for(i = 0; i < output.c; ++i){ |
| | | for(j = 0; j < output.h*output.w; ++j){ |
| | | int index = i*output.h*output.w + j; |
| | | output.data[index] += layer.biases[i]; |
| | | output.data[index] = layer.activation(output.data[index]); |
| | | } |
| | | } |
| | | } |
| | | |
| | | void backpropagate_convolutional_layer(image input, convolutional_layer layer) |
| | | void backward_convolutional_layer(convolutional_layer layer, double *input, double *delta) |
| | | { |
| | | int i; |
| | | zero_image(input); |
| | | |
| | | image in_image = double_to_image(layer.h, layer.w, layer.c, input); |
| | | image in_delta = double_to_image(layer.h, layer.w, layer.c, delta); |
| | | image out_delta = get_convolutional_delta(layer); |
| | | zero_image(in_delta); |
| | | |
| | | for(i = 0; i < layer.n; ++i){ |
| | | back_convolve(input, layer.kernels[i], layer.stride, i, layer.output); |
| | | back_convolve(in_delta, layer.kernels[i], layer.stride, i, out_delta); |
| | | } |
| | | for(i = 0; i < layer.h*layer.w*layer.c; ++i){ |
| | | in_delta.data[i] *= layer.gradient(in_image.data[i]); |
| | | } |
| | | } |
| | | |
| | | /* |
| | | void backpropagate_convolutional_layer_convolve(image input, convolutional_layer layer) |
| | | { |
| | | int i,j; |
| | |
| | | rotate_image(layer.kernels[i]); |
| | | } |
| | | } |
| | | */ |
| | | |
| | | void learn_convolutional_layer(image input, convolutional_layer layer) |
| | | void learn_convolutional_layer(convolutional_layer layer, double *input) |
| | | { |
| | | int i; |
| | | image in_image = double_to_image(layer.h, layer.w, layer.c, input); |
| | | image out_delta = get_convolutional_delta(layer); |
| | | for(i = 0; i < layer.n; ++i){ |
| | | kernel_update(input, layer.kernel_updates[i], layer.stride, i, layer.output); |
| | | kernel_update(in_image, layer.kernel_updates[i], layer.stride, i, out_delta); |
| | | layer.bias_updates[i] += avg_image_layer(out_delta, i); |
| | | } |
| | | image old_input = copy_image(input); |
| | | backpropagate_convolutional_layer(input, layer); |
| | | for(i = 0; i < input.h*input.w*input.c; ++i){ |
| | | input.data[i] *= convolution_gradient(old_input.data[i]); |
| | | } |
| | | free_image(old_input); |
| | | } |
| | | |
| | | void update_convolutional_layer(convolutional_layer layer, double step) |
| | | { |
| | | return; |
| | | int i,j; |
| | | for(i = 0; i < layer.n; ++i){ |
| | | layer.biases[i] += step*layer.bias_updates[i]; |
| | | layer.bias_updates[i] = 0; |
| | | int pixels = layer.kernels[i].h*layer.kernels[i].w*layer.kernels[i].c; |
| | | for(j = 0; j < pixels; ++j){ |
| | | layer.kernels[i].data[j] += step*layer.kernel_updates[i].data[j]; |
| | |
| | | } |
| | | } |
| | | |
| | | void visualize_convolutional_layer(convolutional_layer layer) |
| | | { |
| | | int i; |
| | | char buff[256]; |
| | | //image vis = make_image(layer.n*layer.size, layer.size*layer.kernels[0].c, 3); |
| | | for(i = 0; i < layer.n; ++i){ |
| | | image k = layer.kernels[i]; |
| | | sprintf(buff, "Kernel %d", i); |
| | | if(k.c <= 3) show_image(k, buff); |
| | | else show_image_layers(k, buff); |
| | | } |
| | | } |
| | | |