From 6521badd2d1fdcbe39ac61f8e17dcd6128568193 Mon Sep 17 00:00:00 2001
From: vikshar <viksharrajesh@gmail.com>
Date: Sat, 11 Jan 2025 15:56:14 -0600
Subject: [PATCH] create layers functions

---
 cnn.h | 96 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 94 insertions(+), 2 deletions(-)

diff --git a/cnn.h b/cnn.h
index 68a45b8..a963914 100644
--- a/cnn.h
+++ b/cnn.h
@@ -1,7 +1,8 @@
 // convolutional neural network c header library
 // inspired by euske's nn1
-// meant to be synthesized into RTL through vitus HLS for an FPGA implementation
+// meant to be synthesized into RTL through Vitus HLS for an FPGA implementation
 
+#include <cstdlib>
 #include <stdlib.h>
 #include <math.h>
 
@@ -18,7 +19,7 @@ typedef enum {
 	fc_output,
 } fcpos;
 
-typedef struct Layer {
+typedef struct {
 	ltype type;
 	// spatial extent of layer- l,w,depth (color space)
 	int height;
@@ -51,3 +52,94 @@ typedef struct Layer {
 		} fc_params;
 	} params;
 } Layer;
+
+float random_uniform(float min, float max) {
+	return min + (max - min) * ((float)rand() / RAND_MAX);
+}
+
+float he_uniform(int fan_in) {
+	float limit = sqrt(6.0f / fan_in);
+	return random_uniform((limit * -1), limit);
+}
+
+float glorot_uniform(int fan_in, int fan_out) {
+	float limit = sqrt(6.0f / (fan_in + fan_out));
+  return random_uniform((limit * -1), limit);
+}
+
+
+Layer* create_input(int height, int width, int channels) {
+	Layer* layer = (Layer*)malloc(sizeof(Layer));
+	layer->type = input;
+	layer->height = height;
+	layer->width = width;
+	layer->channels = channels;
+	return layer;
+}
+
+	Layer* create_conv(int height, int width, int channels, int num_filters, int filter_width, int filter_height, int stride, int zero_padding) {
+	Layer* layer = (Layer*)malloc(sizeof(Layer));
+	layer->type = conv;
+	layer->height = height;
+	layer->width = width;
+	layer->channels = channels;
+
+	layer->params.conv_params.num_filters = num_filters;
+	layer->params.conv_params.filter_height = filter_height;
+	layer->params.conv_params.filter_width = filter_width;
+	layer->params.conv_params.stride = stride;
+	layer->params.conv_params.zero_padding = zero_padding;
+
+	// conv layer uses relu - use he init for weights
+	layer->params.conv_params.filters = (float***)malloc(num_filters * sizeof(float**));
+	int fan_in = filter_height * filter_width * channels;
+	for (int f = 0; f < num_filters; f++) {
+		layer->params.conv_params.filters[f] = (float**)malloc(filter_height * sizeof(float*));
+		for (int h = 0; h < filter_height; h++) {
+			layer->params.conv_params.filters[f][h] = (float*)malloc(filter_width * sizeof(float));
+			for (int w = 0; w < filter_width; w++) {
+				layer->params.conv_params.filters[f][h][w] = he_uniform(fan_in);
+			}
+		}
+	}
+
+	return layer;
+}
+
+Layer* create_max_pool(int height, int width, int channels, int pool_height, int pool_width, int stride) {
+	Layer* layer = (Layer*)malloc(sizeof(Layer));
+	layer->type = max_pool;
+	layer->height = height;
+	layer->width = width;
+	layer->channels = channels;
+
+	layer->params.pool_params.pool_height = pool_height;
+	layer->params.pool_params.pool_width = pool_width;
+	layer->params.pool_params.stride = stride;
+
+	return layer;
+}
+
+Layer* create_fc(int input_neurons, int output_neurons, fcpos position) {
+	Layer* layer = (Layer*)malloc(sizeof(Layer));
+	layer->type = fully_connected;
+	layer->height = 1;
+	layer->width = output_neurons;
+	layer->channels = 1;
+
+	layer->params.fc_params.input_neurons = input_neurons;
+	layer->params.fc_params.output_neurons = output_neurons;
+  layer->params.fc_params.position = position;
+
+	// use xav/glorot init b/c of sigmoid
+	layer->params.fc_params.weights = (float**)malloc(output_neurons * sizeof(float*));
+	for (int i = 0; i < output_neurons; i++) {
+		layer->params.fc_params.weights[i] = (float*)malloc(input_neurons * sizeof(float));
+		for (int j = 0; j < input_neurons; j++) {
+			layer->params.fc_params.weights[i][j] = glorot_uniform(input_neurons, output_neurons);
+		}
+	}
+
+	return layer;
+}
+