DDPng

#include <iostream>
#include <fstream>
#include <string>
#include <vector>
#include <algorithm>
#include "HexChar.h"
#include "LodePng.h"

/* HexChar 
 std::ostream& operator<<(std::ostream& o, const HexCharStruct& hs) {
 return (o << std::hex << (int)hs.c); }
 HexCharStruct hex(unsigned char _c) {
 return HexCharStruct(_c); }
*/

void ApplyPostProcess(unsigned int width, unsigned int height, std::vector<unsigned char>& image);

int main(int argc, const char * argv[]) {
    if (argc < 2) {
        std::cout << "Usage: DDPng <string: filename> <bool: post process>\n";
        return 0;
    }
    
    std::vector<unsigned char> png, image;
    unsigned int width, height;
    lodepng::State state;
    lodepng::load_file(png, argv[1]);
    unsigned int error = lodepng::decode(image, width, height, state, png);
    if (error) {
        std::cout << "Error decoding png image\n";
        return 0;        
    } // Image now contains RGBA image
    
    bool postProcessImage = false;
    if (argc >= 3) {
        std::string postProcessArg = argv[2];
        std::transform(postProcessArg.begin(), postProcessArg.end(), postProcessArg.begin(), ::tolower);
        if (postProcessArg == "yes")    postProcessImage = true;
        if (postProcessArg == "y")      postProcessImage = true;
        if (postProcessArg == "1")      postProcessImage = true;
        if (postProcessArg == "true")   postProcessImage = true;
    }
    
    if (postProcessImage)
        ApplyPostProcess(width, height, image);
        
    std::string outFile = argv[1];
    size_t periodPosition = outFile.rfind('.');
    if (periodPosition != std::string::npos) {
        outFile = outFile.erase(periodPosition);
        outFile += ".out";
    }
    
    std::ofstream outputFile;
    outputFile.open(outFile);
     if (!outputFile.is_open()) {
        std::cout << "Error, could not open output file\n";
        return 0;
    }
    
    outputFile << "unsigned int imageWidth = " << width << ";\n";
    outputFile << "unsigned int imageHeight = " << height << ";\n";
    outputFile << "unsigned char imageData[] = { ";
    bool firstChar = true;
    for (unsigned int i = 0, size = (unsigned int)(image.size()); i < size; ++i) {
        if (!firstChar) outputFile << ", ";
        firstChar = false;
        outputFile << "0x" << hex(image[i]);
    }
    outputFile << " };\n";
    outputFile.close();
    
    return 0;
}

void ApplyPostProcess(unsigned int width, unsigned int height, std::vector<unsigned char>& image) {
    for (unsigned int y = 0; y < height; ++y) {
        for (unsigned int x = 0; x < width; ++x) {
            unsigned int pixel = 4 * y * width + 4 * x;
            // +0:R, +1:G, +2:B, +3:A
            if (image[pixel + 0] == 0 && image[pixel + 1] == 0 && image[pixel + 2 == 0]) // Pixel is black
                image[pixel + 0] = image[pixel + 1] = image[pixel + 2] = 255; // Make pixel white
            if (image[pixel + 0] == 255 && image[pixel + 1] == 192 && image[pixel + 2] == 203) // Pixel is pink
                image[pixel + 3] = 0; // No alpha, transparent pixel
            else image[pixel + 3] = 255;
            
        }
    }
}