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@omarojo

omarojo/imageToPixelBuffer.swift

Created February 23, 2017 23:02
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  1. omarojo created this gist Feb 23, 2017.
    58 changes: 58 additions & 0 deletions imageToPixelBuffer.swift
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,58 @@
    var thePixelBuffer : CVPixelBuffer?

    let testImage : UIImage = UIImage.init(named: "twdEnds.png")!
    self.thePixelBuffer = self.pixelBufferFromImage(image: testImage)




    func pixelBufferFromImage(image: UIImage) -> CVPixelBuffer {


    let ciimage = CIImage(image: image)
    //let cgimage = convertCIImageToCGImage(inputImage: ciimage!)
    let tmpcontext = CIContext(options: nil)
    let cgimage = tmpcontext.createCGImage(ciimage!, from: ciimage!.extent)

    let cfnumPointer = UnsafeMutablePointer<UnsafeRawPointer>.allocate(capacity: 1)
    let cfnum = CFNumberCreate(kCFAllocatorDefault, .intType, cfnumPointer)
    let keys: [CFString] = [kCVPixelBufferCGImageCompatibilityKey, kCVPixelBufferCGBitmapContextCompatibilityKey, kCVPixelBufferBytesPerRowAlignmentKey]
    let values: [CFTypeRef] = [kCFBooleanTrue, kCFBooleanTrue, cfnum!]
    let keysPointer = UnsafeMutablePointer<UnsafeRawPointer?>.allocate(capacity: 1)
    let valuesPointer = UnsafeMutablePointer<UnsafeRawPointer?>.allocate(capacity: 1)
    keysPointer.initialize(to: keys)
    valuesPointer.initialize(to: values)

    let options = CFDictionaryCreate(kCFAllocatorDefault, keysPointer, valuesPointer, keys.count, nil, nil)

    let width = cgimage!.width
    let height = cgimage!.height

    var pxbuffer: CVPixelBuffer?
    // if pxbuffer = nil, you will get status = -6661
    var status = CVPixelBufferCreate(kCFAllocatorDefault, width, height,
    kCVPixelFormatType_32BGRA, options, &pxbuffer)
    status = CVPixelBufferLockBaseAddress(pxbuffer!, CVPixelBufferLockFlags(rawValue: 0));

    let bufferAddress = CVPixelBufferGetBaseAddress(pxbuffer!);


    let rgbColorSpace = CGColorSpaceCreateDeviceRGB();
    let bytesperrow = CVPixelBufferGetBytesPerRow(pxbuffer!)
    let context = CGContext(data: bufferAddress,
    width: width,
    height: height,
    bitsPerComponent: 8,
    bytesPerRow: bytesperrow,
    space: rgbColorSpace,
    bitmapInfo: CGImageAlphaInfo.premultipliedFirst.rawValue | CGBitmapInfo.byteOrder32Little.rawValue);
    context?.concatenate(CGAffineTransform(rotationAngle: 0))
    context?.concatenate(__CGAffineTransformMake( 1, 0, 0, -1, 0, CGFloat(height) )) //Flip Vertical
    // context?.concatenate(__CGAffineTransformMake( -1.0, 0.0, 0.0, 1.0, CGFloat(width), 0.0)) //Flip Horizontal


    context?.draw(cgimage!, in: CGRect(x:0, y:0, width:CGFloat(width), height:CGFloat(height)));
    status = CVPixelBufferUnlockBaseAddress(pxbuffer!, CVPixelBufferLockFlags(rawValue: 0));
    return pxbuffer!;

    }