How do I initialize a matchTemplateBuff in OpenCV? - c++

Question

I'm writing a pattern matching code using OpenCV with CUDA on Mac OS X. After ~ 70 frames, it slows down a lot. Using mach_absolute_time() I've been able to track the culprit (Initially I thought it was a disk access issue):
gpu::matchTemplate(currentFrame,
correlationTargets[i]->correlationImage,
temporaryImage,
CV_TM_CCOEFF_NORMED);
I believe this is caused by some memory issue inside matchTemplate. After a lot of search, I found the matchTemplateBuf structure which is presumably for memory reuse. Since the problem seems memory releated, I think using this may be the solution. However, the following code crashes:
gpu::MatchTemplateBuf mtBuff;
[...]
for(...) {
gpu::matchTemplate(correlationTargets[i]->croppedImage,
correlationTargets[i]->correlationImage,
correlationTargets[i]->maxAllocation,
CV_TM_CCOEFF_NORMED, mtBuff);
With error:
OpenCV Error: Gpu API call (Unknown error code [Code = 9999]) in convolve, file /Users/sermarc/Downloads/opencv-2.4-3.8/modules/gpu/src/imgproc.cpp, line 1431 libc++abi.dylib: terminating with uncaught exception of type cv::Exception: /Users/sermarc/Downloads/opencv-2.4-3.8/modules/gpu/src/imgproc.cpp:1431: error: (-217) Unknown error code [Code = 9999] in function convolve
I believe this is because the matchTemplateBuff is not properly initialized. However, I cannot find any information or example that shows it being set on a valid state.
The code works with:
gpu::matchTemplate(correlationTargets[i]->croppedImage,
correlationTargets[i]->correlationImage,
correlationTargets[i]->maxAllocation,
CV_TM_CCOEFF_NORMED);