DepthData - Get per-pixel depth data (CVPixelBuffer data analysis)

问题

Now I run AVDepthPhotoFilter that Rendering Depth Deta from a stereo camera of iPhone7Plus.

So, I want to access per-pixel depth data, but, I don’t know how to do it. Please advice.

回答1:

How to get DepthData and analysis CVPixelBuffer data

You need to make sure your AVCapturePhotoSettings() has isDepthDataDeliveryEnabled = true

You have to use the function func photoOutput(_ output: AVCapturePhotoOutput, didFinishProcessingPhoto photo: AVCapturePhoto, error: Error?)

func photoOutput(_ output: AVCapturePhotoOutput, didFinishProcessingPhoto photo: AVCapturePhoto, error: Error?) {

    //## Convert Disparity to Depth ##

    let depthData = (photo.depthData as AVDepthData!).converting(toDepthDataType: kCVPixelFormatType_DepthFloat32)
    let depthDataMap = depthData.depthDataMap //AVDepthData -> CVPixelBuffer

    //## Data Analysis ##

    // Useful data
    let width = CVPixelBufferGetWidth(depthDataMap) //768 on an iPhone 7+
    let height = CVPixelBufferGetHeight(depthDataMap) //576 on an iPhone 7+
    CVPixelBufferLockBaseAddress(depthDataMap, CVPixelBufferLockFlags(rawValue: 0))

    // Convert the base address to a safe pointer of the appropriate type
    let floatBuffer = unsafeBitCast(CVPixelBufferGetBaseAddress(depthDataMap), to: UnsafeMutablePointer<Float32>.self)

    // Read the data (returns value of type Float)
    // Accessible values : (width-1) * (height-1) = 767 * 575

    let distanceAtXYPoint = floatBuffer[Int(x * y)]

}

If you want more informations about CVPixelBuffer analysis, here is a useful post -> details

来源：https://stackoverflow.com/questions/46794561/depthdata-get-per-pixel-depth-data-cvpixelbuffer-data-analysis

标签

swift

ios11

cvpixelbuffer

iphone7plus