digraph.c

#include <stdio.h>
#include <stdint.h>
#include <math.h>

#include "helpers.c"

#define STB_IMAGE_WRITE_IMPLEMENTATION
#include "stb_image_write.h"

#define MAP_SIZE 256

static size_t map[MAP_SIZE][MAP_SIZE] = {0};
static uint32_t pixels[MAP_SIZE][MAP_SIZE] = {0};

int main(int argc, char *argv[]) {
	Arguments arg = parse_arguments(argc, argv);

	Data data;
	if (strcmp(arg.type, "image") == 0) {
		data = read_image_file_into_array(arg.input_file);
	} else if (strcmp(arg.type, "other") == 0) {
		data = read_binary_file_into_array(arg.input_file);
	} else {
		exit(EXIT_FAILURE);
	}

	memset(map, 0, sizeof(map));
	for (size_t i = 0; i < data.count; i++) {
		uint8_t x = data.content[i];
		uint8_t y = data.content[i+1];
		map[y][x] += 1;
	}

	float max = 0;

	for (size_t y = 0; y < MAP_SIZE; ++y) {
		for (size_t x = 0; x < MAP_SIZE; ++x) {
			float f = 0.0f;
			if (map[y][x] > 0) f = logf(map[y][x]);
			if (f > max) max = f;
		}
	}

	for (size_t y = 0; y < MAP_SIZE; ++y) {
		for (size_t x = 0; x < MAP_SIZE; ++x) {
			float t = logf(map[y][x])/max;
			uint32_t b = t*255;
			pixels[y][x] = 0xFF000000 | b | (b<<8) | (b<<16);
		}
	}

	if (!stbi_write_png(arg.output_file, MAP_SIZE, MAP_SIZE, 4, pixels, MAP_SIZE*sizeof(uint32_t))) {
		printf("Error writing image to file");
		return 1;
	}

	printf("Visualization for %s file %s written to %s\n", arg.type, arg.input_file, arg.output_file);

	return 0;
}