cvaddimage.c

//
// cvaddimage.c
//
// how to compile:
//
//   $ gcc -I/usr/local/opencv2.1/include/ -std=c99 -L/usr/local/opencv2.1/lib -lhighgui -lcv -lcxcore -o cvaddimage cvaddimage.c
//   $ DYLD_LIBRARY_PATH=/usr/local/opencv2.1/lib ./cvmattest
//
// how to run
//
//   ./cvaddimage background_image foreground_image x y width height
//
// example:
//
//   $ ./cvaddimage a.png b.png result.png 100 200 320 240
//
#include <stdio.h>
#include <stdlib.h>
#include <opencv/cv.h>
#include <opencv/cxcore.h>
#include <opencv/highgui.h>

int
main(int argc, char *argv[])
{   
    int x = atoi(argv[4]);
    int y = atoi(argv[5]);
    int w = atoi(argv[6]);
    int h = atoi(argv[7]);

    IplImage *background_img = cvLoadImage(argv[1], CV_LOAD_IMAGE_COLOR);
    IplImage *foreground_img = cvLoadImage(argv[2], CV_LOAD_IMAGE_COLOR);
    IplImage *resize_img = cvCreateImage(cvSize(w, h), IPL_DEPTH_8U, 3);
    IplImage *result_img = cvCreateImage(cvGetSize(background_img), IPL_DEPTH_8U, 3);

    // 背景をコピー
    cvCopy(background_img, result_img, NULL);

    // 前景をリサイズ
    cvResize(foreground_img, resize_img, CV_INTER_NN);

    // イメージを重ねる(foreground_imgはbackground_imgよりも小さい前提w)
    cvSetImageROI(result_img, cvRect(x, y, w, h));
    cvCopy(resize_img, result_img, NULL);
    cvResetImageROI(result_img);

    cvSaveImage(argv[3], result_img, 0);
    //cvSaveImage(argv[3], result_img);  // old opencv style...
    
    cvReleaseImage(&background_img);
    cvReleaseImage(&foreground_img);
    cvReleaseImage(&resize_img);
    cvReleaseImage(&result_img);

    return 0;
}