Deep Copy of CMImageBuffer or CVImageBuffer

Question

Hi I am currently working on an app which needs to capture a Video and at the same time should be able to take frames to blend them. The problem I am having is that my frames coming from:

func captureOutput(
     captureOutput: AVCaptureOutput!,
     didOutputSampleBuffer sampleBuffer:
     CMSampleBuffer!,
     fromConnection connection: AVCaptureConnection!
)

will drop after blending about 10-12 frames. I tried blending every 10th frame but it will still drop after 10-12 blended frames.

I know that I should copy the CVImageBuffer to release the imageBuffer which I got using the following: let imageBuffer = CMSampleBufferGetImageBuffer(sampleBuffer)

I also know that

func CMSampleBufferCreateCopy(
     _ allocator: CFAllocator?,
     _ sbuf: CMSampleBuffer,
     _ sbufCopyOut: UnsafeMutablePointer
) -> OSStatus

only creates shallow copies and won't help releasing the original imageBuffer

So my question is: How can I create a complete deep copy of a CMSmapleBuffer or CVImageBuffer? I would like to use:

func CMSampleBufferCreate(
     _ allocator: CFAllocator?,
     _ dataBuffer: CMBlockBuffer?,
     _ dataReady: Bool,
     _ makeDataReadyCallback: CMSampleBufferMakeDataReadyCallback?,
     _ makeDataReadyRefcon: UnsafeMutablePointer,
     _ formatDescription: CMFormatDescription?,
     _ numSamples: CMItemCount,
     _ numSampleTimingEntries: CMItemCount,
     _ sampleTimingArray: UnsafePointer,
     _ numSampleSizeEntries: CMItemCount,
     _ sampleSizeArray: UnsafePointer,
     _ sBufOut: UnsafeMutablePointer
) -> OSStatus

But the function is a bit overwhelming and I don't know where to get all the attributes from. I am sure I can take a lot from the given CMSmapleBuffer.

I've been looking for a solution for a couple of days now. If you need more context please feel free to ask. I hope somone can help.