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The following code gives seg fault and some time stalls/hangs and never works. 

for(i=0;i<360;i++)

{

CVrotate(image, i); //i is angle


display("image" in some window);  

}

but the following work very well. 

 for(i=0;i<360;i++)

 {

 CVrotate(image, i); //i is angle

 waitkey(10);

 display("image" in some window);  
 }

Cvrotate is a function that is rotating an image, and the rotated image is being displayed by the opencv function for displaying.

Why is waitkey(); needed here? I understand that the display should be called only after CVrotate is done with its job. Similarly, I am assuming that the next iteration starts when the display is over and not before that. Please enlighten me.

Jeru Luke
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gpuguy
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  • If every thing is given in tutorial probably SO would not have come into existence!! I just read the SO FAQ, did not find any place where it says "I can not ask about 10 questions in last two days on Opencv" – gpuguy Jun 20 '12 at 11:05
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    Before asking a question you have to find (Google) similar questions to yours and understand the problem you faced. After this you have to fix/find solution by yourself. But you're just blindly asking a questions. I alerady give you a pointer to the answer - did you find a solution? – ArtemStorozhuk Jun 20 '12 at 11:22
  • Oh Yes, your answer was helpful. – gpuguy Jun 20 '12 at 11:26

1 Answers1

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What does OpenCV's cvWaitKey( ) function do? this link clears all the misconceptions regarding the cvWaitkey and its uses .Hope this is useful for you. cvWaitKey's main function is to pause the code for a while.

Community
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nbsrujan
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  • Reading the original specification Doc did not help me. but this one is now clear to me. Thanks – gpuguy Jun 20 '12 at 11:17