Converts TI-84+ CE .8ci bitmap pictures/images to PNG files

8ci-png.cpp

// requires libpng and png++ (brew install png++) (sudo apt-get install libpng++-dev)
// compile with g++ -o 8ci-png 8ci-png.cpp -lpng
// add -I/usr/local/include if on mac and errors out with "png++/png.hpp: no such file or directory"
#include <iostream>
#include <fstream>
#include <vector>
#include <png++/png.hpp>

//-----------8ci palette---------------
std::vector<png::rgb_pixel> colors = {
    {255, 255, 255}, // white/none
    {0, 0, 255},     // BLUE
    {255, 0, 0},     // RED
    {0, 0, 0},       // BLACK
    {255, 0, 255},   // MAGENTA
    {0, 255, 0},     // GREEN
    {255, 160, 0},   // ORANGE
    {128, 32, 0},    // BROWN
    {0, 0, 128},     // NAVY
    {0, 144, 255},   // LTBLUE
    {255, 255, 0},   // YELLOW
    {255, 255, 255}, // WHITE
    {192, 192, 192}, // LTGRAY
    {128, 128, 128}, // MEDGRAY
    {96, 96, 96},    // GRAY
    {64, 64, 64}     // DARKGRAY
};

enum colors {
    COLOR_NONE,
    COLOR_BLUE,
    COLOR_RED,
    COLOR_BLACK,
    COLOR_MAGENTA,
    COLOR_GREEN,
    COLOR_ORANGE,
    COLOR_BROWN,
    COLOR_NAVY,
    COLOR_LTBLUE,
    COLOR_YELLOW,
    COLOR_WHITE,
    COLOR_LTGRAY,
    COLOR_MEDGRAY,
    COLOR_GRAY,
    COLOR_DARKGRAY
};
//-------------------------------------

int main(int argc, const char * argv[]) {
    if (argc < 2) {
        std::cerr << "Usage: " << argv[0] << " <input.8ci> [output.png]\n";
        return 1;
    }
    std::string out = std::string(argv[1]) + ".png";
    if (argc > 2) out = std::string(argv[2]);
    std::ifstream in(argv[1]);
    if (!in.is_open()) {
        std::cerr << "Could not open " << argv[1] << ".\n";
        return 2;
    }
    in.seekg(74); // this may or may not always hold true
    png::image<png::rgb_pixel> img(266, 165); // same here
    int x = 0, y = 0;
    while (!in.eof() && y < 165) {
        char ch = in.get();
        img.set_pixel(x++, y, colors[(ch & 0xF0) >> 4]);
        img.set_pixel(x++, y, colors[ch & 0x0F]);
        if (x > 265) {x = 0; y++;}
    }
    img.write(out);
    std::cout << "Wrote image\n";
    return 0;
}