Write depthMap buffer to file (Swift)

Question

I work with the new iPadPro and a LIDAR app and am kinda new to SWIFT5 (normaly working on CordovaApps with minimal native coding needed)

I want to dump the CVPixelBuffer I get for a frame to a .bin file.

I get the buffer like this: let depthMap = frame.sceneDepth!.depthMap It returns a DepthFloat32 buffer.

After that I lock the address and fetch it:

CVPixelBufferLockBaseAddress(depthMap, CVPixelBufferLockFlags(rawValue: 0))
var addr = CVPixelBufferGetBaseAddress(depthMap)

How can I save these values to a file on my iPad? Would be thankful for any help.

Answer 1

I solved it on my own. Here is my solution in case somebody needs it.

Gather all the necessary values:

let addr = CVPixelBufferGetBaseAddress(depthMap)
let height = CVPixelBufferGetHeight(depthMap)
let bpr = CVPixelBufferGetBytesPerRow(depthMap)

Then I hand the bufferaddress to the Data obj to create a byte buffer in memory --> Data

let data = Data(bytes: addr!, count: (bpr*height))
do {
   let filename = getDirectory().appendingPathComponent(timestamp +"_depthbuffer.bin")
   try data.write(to: filename)
} catch {
   // do smth with errors
}

getDirectory() is a custom function to find the Documents Directory. I can get the created Files from the App Container.

Don't forgett to Lock & unlock the BufferAdress.