Does image subtraction work with both types of Mat?

[Haprst]

I want to subtract one IplImage from another. Since IplImage has no arithmetic methods, I converted them to Mat. But then subtract seems to expect a different type of Mat, and the error message indicates that I should be using opencv.core instead of opencv_core. Is it safe to change just 1 include in 1 file "import org.bytedeco.opencv.opencv_core.Mat"? I have eleven other includes that specify opencv_core in this file, and in 7 other files in this project. The relevant code is the first three lines. Neither of the next two lines works. "No suitable method found for subtract".
BUG.txt

[saudet]

We can convert between both types of Mat using OpenCVFrameConverter when necessary:
http://bytedeco.org/javacv/apidocs/org/bytedeco/javacv/OpenCVFrameConverter.html

[Haprst]

To make this easier, I spent a few hours reducing my long 7 file program to a single minimal file. I created a relatively small Test.jpg image which I'm not bothering to send.

At the moment, the 5 problematic statements are undented and surrounded by System.out.println statements, so they're easy to find. The first two statements are those you suggested earlier today. One is commented out. When the original Loader... statement is active, it requires the first two import statements. When it's replaced with your newer suggestion, those two imports are never used. Neither of those Loader statements solves any of the problems. Is it possible that import statements are causing the problems?
TLbug.txt

[saudet]

You mean these errors? You'll need to use a OpenCVFrameConverter.ToMat to fix those.

edeputy.java:77: error: cannot find symbol
    Core.subtract(blueMat1, greenMat1, redMat1);
    ^
  symbol:   variable Core
  location: class edeputy
edeputy.java:99: error: incompatible types: org.opencv.core.Mat cannot be converted to org.bytedeco.opencv.opencv_core.Mat
    Mat blueMat2 = convMatMat1x.convert(blueFrame);
                                       ^
edeputy.java:100: error: incompatible types: org.opencv.core.Mat cannot be converted to org.bytedeco.opencv.opencv_core.Mat
    Mat greenMat2 = convMatMat2x.convert(greenFrame);
                                        ^
edeputy.java:101: error: incompatible types: org.opencv.core.Mat cannot be converted to org.bytedeco.opencv.opencv_core.Mat
    Mat redMat2 = convMatMat3x.convert(redFrame);
                                      ^
edeputy.java:109: error: cannot find symbol
    Core.subtract(blueMat2, greenMat2, redMat2);
    ^
  symbol:   variable Core
  location: class edeputy
5 errors
error: compilation failed

[Haprst]

Lines 77and 109 are the problem. In both of these lines, the error is Can't find symbol variable Core. For line 77, you say above I need to use OpenCVFrameConverter.ToMat. But I used exactly that on lines 64 to 66. When that didn't work, and NetBeans didn't suggest a missing include, you suggested ToOrgOpenCvCoreMat. That was the sole reason why I created an alternative 2nd section using instead ToOrgOpenCvCoreMat(). So let's return to line 77. If I used the right method there, then the question is simply why isn't Core resolved? Lines 3 and 4 are imports that reference Core, but evidently something is missing, because Core is not found.

[Haprst]

And the answer is that in line 77 "core is not found, but in line 109 "Core" is NOT NEEDED!

[saudet]

Right, I don't think you need the Core class, but if you do, it's this one here:
http://bytedeco.org/javacpp-presets/opencv/apidocs/org/opencv/core/Core.html