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namedWindow does not show window

asked 2015-01-30 11:14:03 -0500

Kinimod gravatar image

updated 2015-01-30 12:47:13 -0500


I'm using VC12 and Win8.1. I think that I configured my project fine, because it compiles.

I use this sample code

So I run the application without debugging about VC12. The Message " Usage: display_image ImageToLoadAndDisplay" is displayed and the console application waits for key stroke. But no new window will be displayed.

Same issue by executing the program about command prompt.

I tried also the execution by using admin rights, but it does not display any new window.

Any hints for fixing this issue?

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display_image lena.png

(it wants an image as a cmdline argument)

((you can probably even drag & drop an image onto your exe))

(((also, no worries, if you got here, you've done everything right so far..)))

berak gravatar imageberak ( 2015-01-30 11:30:04 -0500 )edit

yes, I know... so the sample works here on my machine and finds the referenced image, because it does not return -1 and waits for a key stroke, but the image window is not displayed.

Kinimod gravatar imageKinimod ( 2015-01-30 12:40:28 -0500 )edit

wait, back to start. look at line 12. as long as you see that message, you did not supply correct cmdline args

berak gravatar imageberak ( 2015-01-30 12:50:01 -0500 )edit

Oh... sorry, you're right... So I hard coded the reference and removes the argument condition

//if (argc != 2)
//  cout << " Usage: display_image ImageToLoadAndDisplay" << endl;
//  return -1;

So I have figure out now what's going wrong by executing the exe with command prompt. Thank you. Now it works fine.

Kinimod gravatar imageKinimod ( 2015-01-30 13:33:19 -0500 )edit

btw, look at the properties sheet, debugging settings. you can set startup path and cmdline args there

(you'll encounter that problem quite often..)

berak gravatar imageberak ( 2015-01-30 13:36:24 -0500 )edit

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answered 2015-01-30 12:24:22 -0500

Doombot gravatar image

@berak's comment is right. I would add that for me, it was easier to place an image in a specific path on my computer, then hardcode the path like this:

Mat image;

string path = "C:/myfirstimage.jpg";

image = imread( path );

From there, I was able to elaborate (like, scanning through a folder and display all images, one at a time, etc.).

As I said, I was not that familiar with VS command line at the time so this was easier for me, but others might realy prefer the command line...

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Thanks, but my issue is that the image window is not displayed. So it finds referenced image, but the image window is not displayed.

Kinimod gravatar imageKinimod ( 2015-01-30 12:43:32 -0500 )edit

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Asked: 2015-01-30 11:14:03 -0500

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Last updated: Jan 30 '15