Memory Leak in cvLoadImage or JavaCV (Big Issue, New problem) about javacv HOT 17 CLOSED

I have also read the source code from javacv/opencv_highgui.

It seems the jni wrapper directly called the OpenCV's original code.
Probably it's a problem with the interface to the original C++ code. This is 
the reason why we only observe the global memory leak but not for the running 
Java thread.

I am seeing the same problem.  in my case, I load the image via 
IplImage.createFrom(java.awt.image.BufferedImage)

oh, great. Actually I have tried to copy from BufferedImage one pixel by one 
pixel to the IplImage.

Now the problem has gone. At least, when java program terminates, the global 
memory will be freed.

Thank you again.

Yes, first things first, this may very well be a problem inside OpenCV. Could 
you try to run this cvLoadImage()/cvReleaseImage() loop in a C/C++ program and 
see what that gives? Thank you

BTW, we can also use IplImage.copyFrom() to copy from a BufferedImage.

I didn't try that.  But I used OpenCV in C++ 4 years ago, no problem with that. 
And Also don't remember anyone report that bug in the group.

I guess for JavaCV, we should recommend people use IplImage.copyFrom for 
current version.

[deleted comment]

They changed most of the code (for the worse IMO) since OpenCV 2.0, so it would 
NOT surprise me to see issues like that, especially in the "deprecated" C 
API... ah well. But then again, it may be JavaCV for some reason. Let me know 
if you test it in C/C++, thanks.

I will try the C/C++ test.  BTW, in my app I am using HPROF and noticing a huge 
number of JNI global references building up over time (like almost 2 million).

well, it seems that OpenCV didn't fix the problem of cvloadimage in C++. 
Instead we can use CVVimage:load.

Regarding my question, in javacv, I use iplimage.createfrom, there is still 
memory leak accumulated. It's really strange. For 20 test images, the memory 
will be released and back to original level after the program terminates. When 
I run it on 60000 images, it will occupy 10 G memory finally and not release 
the memory even after the program terminates.

I have just tried that cvLoadImage()/cvReleaseImage() loop in both C/C++ and 
Java here and I get no memory leak at all...

C/C++:
int main(int argc, const char *argv[]) {
    for (int i = 0; i < 1000000; i++) {
        IplImage *image = cvLoadImage(argv[1]);
        cvReleaseImage(&image);
    }
}

Java:
public static void main(String[] args) {
    for (int i = 0; i < 1000000; i++) {
        IplImage image = cvLoadImage(args[0]);
        cvReleaseImage(image);
        image = null;
        System.gc();
    }
}

using both lena.jpg and box_in_scene.png image files that come with OpenCV, no 
problem at all.

OpenJDK Runtime Environment (IcedTea6 1.9.10) (fedora-55.1.9.10.fc14-x86_64)
OpenJDK 64-Bit Server VM (build 19.0-b09, mixed mode)
and OpenCV 2.3.1 and JavaCV 2011-10-01

Let me know if you have more information that may be relevant. It seems to work 
fine here.

I have memory leaks working with IplImage.create and BufferedImages, and a 
strange crash that always happens the 3rd time I call IplImage.create.

I attach my testsuite which isolates the issue as much as possible. 

the.duckman, after removing the incorrect calls to `cvReleaseImage()`, the code 
you posted works just fine for me on the `lena.jpg` sample image file that 
comes with OpenCV... Do you still have issues after removing the calls to 
`cvReleaseImage()`?

Cheers Samuel, sorry to take so long to get back to you.

It works (but causes a memory leak), I don't follow why the calls (line 156, 
158) are incorrect. Can you elaborate a bit for me please?

cvReleaseImage() is just a normal function, it does not cancel the 
PhantomReference inside Pointer as set by IplImage.create() or 
IplImage.createFrom(). We need to call IplImage.release() for an IplImage image 
allocated that way, when we want memory to be deallocated "right now" that is. 
Otherwise, the garbage collector will deallocate memory, eventually, possibly 
not before the program terminates though...

Thankyou your advice was most helpfull. I have use IplImage.release() and all 
issues were resolved.

-dm

So, is everything alright? Since I am unable to reproduce the problem, I am 
marking as invalid, but please let me know if you still have some issue, thank 
you.

I run some pretty heavy unit tests on Win64. Currently able to process very
large quantities of data without any memory leak issues.

cheers.

-dm