I want to release the CVPixelBufferRef in swift - ios

Question

I want to create a video from image.
So, I was the source of the link to the reference.
Link:CVPixelBufferPool Error ( kCVReturnInvalidArgument/-6661)
func writeAnimationToMovie(path: String, size: CGSize, animation: Animation) -> Bool {
var error: NSError?
let writer = AVAssetWriter(URL: NSURL(fileURLWithPath: path), fileType: AVFileTypeQuickTimeMovie, error: &error)
let videoSettings = [AVVideoCodecKey: AVVideoCodecH264, AVVideoWidthKey: size.width, AVVideoHeightKey: size.height]
let input = AVAssetWriterInput(mediaType: AVMediaTypeVideo, outputSettings: videoSettings)
let pixelBufferAdaptor = AVAssetWriterInputPixelBufferAdaptor(assetWriterInput: input, sourcePixelBufferAttributes: nil)
input.expectsMediaDataInRealTime = true
writer.addInput(input)
writer.startWriting()
writer.startSessionAtSourceTime(kCMTimeZero)
var buffer: CVPixelBufferRef
var frameCount = 0
for frame in animation.frames {
let rect = CGRectMake(0, 0, size.width, size.height)
let rectPtr = UnsafeMutablePointer<CGRect>.alloc(1)
rectPtr.memory = rect
buffer = pixelBufferFromCGImage(frame.image.CGImageForProposedRect(rectPtr, context: nil, hints: nil).takeUnretainedValue(), size)
var appendOk = false
var j = 0
while (!appendOk && j < 30) {
if pixelBufferAdaptor.assetWriterInput.readyForMoreMediaData {
let frameTime = CMTimeMake(Int64(frameCount), 10)
appendOk = pixelBufferAdaptor.appendPixelBuffer(buffer, withPresentationTime: frameTime)
// appendOk will always be false
NSThread.sleepForTimeInterval(0.05)
} else {
NSThread.sleepForTimeInterval(0.1)
}
j++
}
if (!appendOk) {
println("Doh, frame \(frame) at offset \(frameCount) failed to append")
}
}
input.markAsFinished()
writer.finishWritingWithCompletionHandler({
if writer.status == AVAssetWriterStatus.Failed {
println("oh noes, an error: \(writer.error.description)")
} else {
println("hrmmm, there should be a movie?")
}
})
return true;
}
func pixelBufferFromCGImage(image: CGImageRef, size: CGSize) -> CVPixelBufferRef {
let options = [
kCVPixelBufferCGImageCompatibilityKey: true,
kCVPixelBufferCGBitmapContextCompatibilityKey: true]
var pixBufferPointer = UnsafeMutablePointer<Unmanaged<CVPixelBuffer>?>.alloc(1)
let status = CVPixelBufferCreate(
nil,
UInt(size.width), UInt(size.height),
OSType(kCVPixelFormatType_32ARGB),
options,
pixBufferPointer)
CVPixelBufferLockBaseAddress(pixBufferPointer.memory?.takeUnretainedValue(), 0)
let rgbColorSpace = CGColorSpaceCreateDeviceRGB()
let bitmapinfo = CGBitmapInfo.fromRaw(CGImageAlphaInfo.NoneSkipFirst.toRaw())
var pixBufferData:UnsafeMutablePointer<(Void)> = CVPixelBufferGetBaseAddress(pixBufferPointer.memory?.takeUnretainedValue())
let context = CGBitmapContextCreate(
pixBufferData,
UInt(size.width), UInt(size.height),
8, UInt(4 * size.width),
rgbColorSpace, bitmapinfo!)
CGContextConcatCTM(context, CGAffineTransformMakeRotation(0))
CGContextDrawImage(
context,
CGRectMake(0, 0, CGFloat(CGImageGetWidth(image)), CGFloat(CGImageGetHeight(image))),
image)
CVPixelBufferUnlockBaseAddress(pixBufferPointer.memory?.takeUnretainedValue(), 0)
return pixBufferPointer.memory!.takeUnretainedValue()
}
Something even after the Movies can be as under the image remains in memory.
I believe or not than is left PixcelBuffer.
I had a method CVPixelBufferRelease(buffer) to release the PixcelBuffer when the Objective-c, I'm no longer can use this in Swift. How do I release the PixcelBuffer doing?
If anyone could help, I'd really appreciate it.
1
2

Answer 1

When using CVPixelBufferCreate the UnsafeMutablePointer has to be destroyed after retrieving the memory of it.
When I create a CVPixelBuffer, I do it like this:
func allocPixelBuffer() -> CVPixelBuffer {
let pixelBufferAttributes : CFDictionary = [...]
let pixelBufferOut = UnsafeMutablePointer<CVPixelBuffer?>.alloc(1)
_ = CVPixelBufferCreate(kCFAllocatorDefault,
Int(Width),
Int(Height),
OSType(kCVPixelFormatType_32ARGB),
pixelBufferAttributes,
pixelBufferOut)
let pixelBuffer = pixelBufferOut.memory!
pixelBufferOut.destroy()
return pixelBuffer
}

Answer 2

I had same problem, but I have solved.
Use this: autoreleasepool
var boolWhile = true
while (boolWhile) {
autoreleasepool({() -> () in
if(input.readyForMoreMediaData) {
presentTime = CMTimeMake(Int64(ii), fps)
if(ii >= arrayImages.count){
...

Answer 3

Try changing
return pixBufferPointer.memory!.takeUnretainedValue()
to
return pixBufferPointer.memory!.takeRetainedValue()
to avoid leaking CVPixelBuffers