image concatenate

imcon.cpp

//
// imcon
//      image concatenater
// usage:
//      imcon [img]+
//

#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>

#include <iostream>
#include <vector>
#include <string>
#include <boost/regex.hpp>

using namespace cv;
using namespace std;

void
usage(char *cmd) {
    cerr << "[usage] " << cmd << " [images]+" << endl;
}

void
show_wait(Mat img) {
    namedWindow("name", CV_WINDOW_AUTOSIZE);
    imshow("name", img);
    waitKey(0);
}

string
normalize_filestr(const char *chrs) {
    string str = chrs;
    boost::regex re("[0-9]+");
    string result = boost::regex_replace(str, re, "");

    cout << result << endl;
    return result;
}

Mat
create_mask(Mat img) {
    Mat mask(Size(img.cols, img.rows), CV_8UC1);
    int ch = img.channels();

    for (int y=0; y<img.rows; y++) {
        for (int x=0; x<img.cols; x++) {
            int a = img.step  * y + x * ch;
            int b = mask.step * y + x;

            if ( img.data[a+0] == 0
              && img.data[a+1] == 0
              && img.data[a+2] == 0) {
                mask.data[b] = 0;
            }
            else {
                mask.data[b] = 255;
            }
        }
    }

    return mask;
}

Mat
add_channel(Mat img) {
    vector<Mat> channels;
    split(img, channels);

    Mat mask = create_mask(img);
    channels.push_back(mask);

    Mat bgra;
    merge(channels, bgra);

    return bgra;
}

int
main(int argc, char** argv) {
    // argument check
    if (argc <= 1) {
        usage(argv[0]);
        return 1;
    }

    // measure
    vector<Mat> list;
    int total_width = 0;
    int max_height  = 0;

    for (int i=1; i<argc; i++) {
        cout << "[load] " << argv[i] << endl;
        list.push_back(imread(argv[i]));

        Mat last = list.back();
        if (last.empty()) {
            cout << "empty image: " << argv[i] << endl;
            return 1;
        }

        total_width += last.cols;
        max_height = max(max_height, last.rows);
    }

    cout << "[total_width] " << total_width << endl;
    cout << "[max_height]  " << max_height << endl;

    // joint
    Mat combined(Size(total_width, max_height), CV_8UC3);
    vector<Mat>::iterator it     = list.begin();
    vector<Mat>::iterator it_end = list.end();

    Rect roi_rect;
    while (it != it_end) {
        roi_rect.width  = it->cols;
        roi_rect.height = it->rows;

        Mat roi(combined, roi_rect);
        it->copyTo(roi);

        roi_rect.x += it->cols;

        ++it;
    }

    // 3channel -> 4channel
    Mat merged = add_channel(combined);

    // write
    string filestr = argv[1];
    string newstr = normalize_filestr(argv[1]);
    imwrite(newstr.c_str(), merged);
}