open cv ios video processing

Question

I\'m trying to do the tutorial found here for ios video processing with openCv framework.

I\'ve successfully loaded the ios openCv framework to my project -

Answer 1

This is the updated version of the code in the previous accepted answer which should work with any iOS device.

Since bufferWidth is not equal to bytePerRow at least on iPhone 6 and iPhone 6+, we need to specify the number of byte in each rows as the last argument to the cv::Mat constructor.

CVImageBufferRef pixelBuffer = CMSampleBufferGetImageBuffer(sampleBuffer);

CVPixelBufferLockBaseAddress(pixelBuffer, 0);

int bufferWidth = CVPixelBufferGetWidth(pixelBuffer);
int bufferHeight = CVPixelBufferGetHeight(pixelBuffer);
int bytePerRow = CVPixelBufferGetBytesPerRow(pixelBuffer);
unsigned char *pixel = (unsigned char *) CVPixelBufferGetBaseAddress(pixelBuffer);
cv::Mat image = cv::Mat(bufferHeight, bufferWidth, CV_8UC4, pixel, bytePerRow); 

// Process you cv::Mat here

CVPixelBufferUnlockBaseAddress(pixelBuffer, 0);

The code has been tested on my iPhone5, iPhone6 and iPhone6+ running iOS 10.