seam-carving/src/seam-carving.cpp
2025-03-25 12:13:40 +01:00

90 lines
2.8 KiB
C++

#include <iostream>
#include <string>
#include <random>
#include <vector>
//Command-line parsing
#include <CLI11.hpp>
//Image filtering and I/O
#define STB_IMAGE_IMPLEMENTATION
#include <stb_image.h>
#define STB_IMAGE_WRITE_IMPLEMENTATION
#include <stb_image_write.h>
//Global flag to silent verbose messages
bool silent;
bool test_energy;
/** e_1 energy */
std::vector<unsigned char> energy_e1(unsigned char* source, int width, int height, int nbChannels) {
std::vector<unsigned char> energy(width*height);
for (auto i=0; i < width*height; i++) { energy[i] = 0; }
for(auto i = 0 ; i < width ; ++i) {
for(auto j = 0; j < height; ++j) {
auto indexPixel = nbChannels*(width*j+i);
auto indexPixel_up = (j-1 > 0) ? nbChannels*(width*(j-1)+i) : indexPixel;
auto indexPixel_down = (j+1 < height) ? nbChannels*(width*(j+1)+i) : indexPixel;
auto indexPixel_left = (i-1 > 0) ? nbChannels*(width*j+(i-1)) : indexPixel;
auto indexPixel_right = (i+1 < width) ? nbChannels*(width*j+(i+1)) : indexPixel;
for (auto ch=0; ch < nbChannels; ch++) {
energy[width*j+i] += (
fabs((float)source[indexPixel_up+ch] - source[indexPixel+ch])
+fabs((float)source[indexPixel_down+ch] - source[indexPixel+ch])
+fabs((float)source[indexPixel_left+ch] - source[indexPixel+ch])
+fabs((float)source[indexPixel_right+ch] - source[indexPixel+ch])
)/(nbChannels*4);
}
}
}
return energy;
}
int main(int argc, char **argv) {
CLI::App app{"seam-carving"};
std::string sourceImage;
app.add_option("-s,--source", sourceImage, "Source image")->required()->check(CLI::ExistingFile);;
std::string outputImage= "output.png";
app.add_option("-o,--output", outputImage, "Output image")->required();
silent = false;
app.add_flag("--silent", silent, "No verbose messages");
test_energy = false;
app.add_flag("--test-energy", test_energy, "Don't resize image, just try the specified energy function");
CLI11_PARSE(app, argc, argv);
//Image loading
int width, height, nbChannels;
unsigned char *source = stbi_load(sourceImage.c_str(), &width, &height, &nbChannels, 0);
if (nbChannels < 3) { // TODO : really ?
std::cout<< "Input images must be RGB images."<<std::endl;
exit(1);
}
int outChannels = nbChannels;
std::vector<unsigned char> output;
if (test_energy) {
outChannels = 1;
output = energy_e1(source, width, height, nbChannels);
} else {
std::cout <<"Not implemented" << std::endl;
exit(1);
}
//Final export
if (!silent) std::cout<<"Exporting.."<<std::endl;
int errcode = stbi_write_png(outputImage.c_str(), width, height, outChannels, output.data(), outChannels*width);
if (!errcode) {
std::cout<<"Error while exporting the resulting image."<<std::endl;
exit(errcode);
}
stbi_image_free(source);
exit(0);
}