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C ++ / cv :: Mat equivalent to creating IplImage using memcpy

I was given some code where IplImage is created using memcpy and then converted to cv :: Mat:

IplImage* iplImage = cvCreateImage(cv::Size(imageWidth, imageHeight), IPL_DEPTH_8U, bytesPerPixel);
memcpy(iplImage->imageData, memory, imageWidth * imageHeight * bytesPerPixel);
cv::Mat image = cv::cvarrToMat(iplImage, true, true, 0);
cvReleaseImage(&iplImage);

memory is a pointer to a void pointer to the beginning of a memory block.

I want to port this code to use only OpenCV C ++ Api. This is what I tried first:

cv::Mat image(cv::Size(imageWidth, imageHeight), CV_MAKETYPE(CV_8U, bytesPerPixel), memory);

But the image is empty.

Then I tried this:

cv::Mat image(cv::Size(imageWidth, imageHeight), CV_MAKETYPE(CV_8U, bytesPerPixel));
memcpy(image.data, memory, imageWidth * imageHeight * bytesPerPixel);

This method works, but it uses a lot more RAM (about 100 MB), so I assume there is unnecessary copying.

What would be the right way to do this?

EDIT: The memory is indeed in a wrapper class. It is automatically released. I just changed it to "memory."

EDIT2: Here is the complete code, including the object from which the memory originates:

cv::Mat RecordingPlayer::next() {
    if (currentContainer.getDataType() == odcore::data::image::SharedImage::ID()) {
        odcore::data::image::SharedImage sharedImage = currentContainer.getData<odcore::data::image::SharedImage>();
        std::shared_ptr<odcore::wrapper::SharedMemory> memory = odcore::wrapper::SharedMemoryFactory::attachToSharedMemory(sharedImage.getName());
        IplImage* iplImage = cvCreateImage(imageSize(), IPL_DEPTH_8U, bytesPerPixel);
        memcpy(iplImage->imageData, memory->getSharedMemory(), imageWidth * imageHeight * bytesPerPixel);
        cv::Mat image = cv::cvarrToMat(iplImage, true, true, 0);
        cvReleaseImage(&iplImage);
        return image;
    } else {
        return cv::Mat();
    }
}
+4
1

, memory->getSharedMemory() , .

OpenCV , . . - clone():

cv::Mat image = Mat(cv::Size(imageWidth, imageHeight), CV_MAKETYPE(CV_8U, bytesPerPixel), memory->getSharedMemory()).clone();
+4

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