captureOutput.swift

 func captureOutput(_ output: AVCaptureOutput, didOutput sampleBuffer: CMSampleBuffer, from connection: AVCaptureConnection) {
        guard let pixelBuffer = CMSampleBufferGetImageBuffer(sampleBuffer) else {
            return
        }
        
        let imageRequestHandler = VNImageRequestHandler(cvPixelBuffer: pixelBuffer, orientation: .right, options: [:])
        do {
            let start = CACurrentMediaTime()
            try imageRequestHandler.perform(self.requests)
            inferenceTime = (CACurrentMediaTime() - start)

        } catch {
            print(error)
        }
    }