In openCV programming by visual studio c++ if i get argc=1 i cant load picture,how can i fix it?

Question

I copy this code from openCV2 book and this code have argc and argv as arguments that I don't know what they are and why assign to 1 (argc=1) and terminate debugging ...my problem that why argc=1? And how I can fix it? because my argc should be 2 (argc==2)...

#include <stdio.h>
#include <opencv2/opencv.hpp>
using namespace cv;
int main( int argc, char** argv )
{
  if ( argc ! = 2 )
  {
    printf( " usage: DisplayImage.out <Image_Path>\n" );
    return - 1;
  }
  Mat image;
  image = imread( argv[ 1], 1 );
  if ( ! image.data )
  {
    printf( " No image data \n" );
    return - 1;
  }
  namedWindow( " Display Image" , WINDOW_AUTOSIZE );
  imshow( " Display Image" , image);
  waitKey( 0);
  return 0;
}

I try to wrote this code without argc and argv but the debugger has a runtime error that i think its cause be argc.

You have to tell the command line arguments to pass to main within your debug project properties. — πάντα ῥεῖ, Aug 09 '15 at 12:07
@saeed masoomi What are you going to change in the program? It is clear written in the program itself how to run it: " usage: DisplayImage.out \n". — Vlad from Moscow, Aug 09 '15 at 12:07
@saeed masoomi By the way if it is indeed a code from a book then the book is bad.:) Though as for me then I do not read books. I only see pictures. — Vlad from Moscow, Aug 09 '15 at 12:09

score 0 · Accepted Answer · edited May 23 '17 at 12:14

If you run it by command line, you can call it as

DisplayImage "path_to_image"

If you want to run from VS, be sure to add the "path_to_image" in your command arguments:

PROJECT -> Properties -> Configuration Properties -> Debugging
Put the "path_to_image" in Command Arguments

Be sure that "path_to_image" is a valid path, check here for reference.

As already pointed out in comments, it's a very bad example! OpenCV 3.0.0 has also CommandLineParser for more complex input arguments.

In openCV programming by visual studio c++ if i get argc=1 i cant load picture,how can i fix it?

1 Answers1