Deep Copying of CMSampleBuffer and CVPixelBuffer

CVPixelBuffer+CMSampleBuffer+Copy.swift

//
//  CVPixelBuffer+CMSampleBuffer+Copy.swift
//  VideoDelaySwift
//
//  Created by michal on 16/07/2019.
//  Copyright © 2019 michal. All rights reserved.
//

import AVFoundation

extension CMSampleBuffer {
    
    var deepCopy: CMSampleBuffer {
        #if targetEnvironment(simulator)
        return self
        #else
        guard let pixelBuffer = CMSampleBufferGetImageBuffer(self) else {
            fatalError("can't get pixelBuffer \(#line)")
        }
        guard let formatDescription = CMSampleBufferGetFormatDescription(self) else {
            fatalError("can't get formatDescription \(#line)")
        }
        let copiedBuffer = pixelBuffer.deepCopy
        var sampleTiming = CMSampleTimingInfo(duration: .invalid, presentationTimeStamp: .invalid, decodeTimeStamp: .invalid)
        var sampleBufferCopy: CMSampleBuffer?
        let match = CMVideoFormatDescriptionMatchesImageBuffer(formatDescription, imageBuffer: copiedBuffer)
        let _ = CMVideoFormatDescriptionGetExtensionKeysCommonWithImageBuffers()
        precondition(match, "doesn't match \(formatDescription)")
        CMSampleBufferGetSampleTimingInfo(self, at: 0, timingInfoOut: &sampleTiming)
        let status = CMSampleBufferCreateReadyWithImageBuffer(
            allocator: kCFAllocatorDefault,
            imageBuffer: copiedBuffer,
            formatDescription: formatDescription,
            sampleTiming: &sampleTiming,
            sampleBufferOut: &sampleBufferCopy)
        precondition(status == 0, "CMSampleBufferCreateReadyWithImageBuffer failed \(status) at \(#line)")
        guard let buffer = sampleBufferCopy else {
            fatalError("could not copy buffer \(#line)")
        }
        return buffer
        #endif
    }
}

extension CVPixelBuffer {
    var deepCopy: CVPixelBuffer {
        CVPixelBufferLockBaseAddress(self, [])
        let width = CVPixelBufferGetWidth(self)
        let height = CVPixelBufferGetHeight(self)
        let baseAddress = CVPixelBufferGetBaseAddressOfPlane(self, 0)
        var bufferToCopy: CVPixelBuffer?
        let pixelBufferAttributes = [kCVPixelBufferIOSurfacePropertiesKey: [:] as AnyObject]
        
        let status = CVPixelBufferCreate(kCFAllocatorDefault,
                                         width,
                                         height,
                                         kCVPixelFormatType_420YpCbCr8BiPlanarFullRange,
                                         pixelBufferAttributes  as CFDictionary?,
                                         &bufferToCopy)
        precondition(status == 0, "failed creating pixelbuffer \(status) at \(#line)")
        
        guard let bufferCopy = bufferToCopy else {
            fatalError("bufferCopy nil \(#line)")
        }
        
        CVPixelBufferLockBaseAddress(bufferCopy, [])
        CVBufferPropagateAttachments(self, bufferCopy)
        
        let copyBaseAddress = CVPixelBufferGetBaseAddressOfPlane(bufferCopy, 0)
        let size = CVPixelBufferGetDataSize(bufferCopy)
        memcpy(copyBaseAddress, baseAddress, size)
        CVPixelBufferUnlockBaseAddress(bufferCopy, [])
        CVPixelBufferUnlockBaseAddress(self, [])
        return bufferCopy
    }
}