let font=CTFontCreateWithName("Courier",25.0,nil)
var keys = [ unsafeAddressOf(kCTFontAttributeName) ]
var values = [ unsafeAddressOf(font) ]
var keyCallbacks = kCFTypeDictionaryKeyCallBacks
var valueCallbacks = kCFTypeDictionaryValueCallBacks
let attributes = CFDictionaryCreate(nil, &keys, &values, 1, &keyCallbacks, &valueCallbacks)
let attrString = CFAttributedStringCreate(nil, "Hello", attributes)

let myDesTypes:CFArrayRef = CGImageDestinationCopyTypeIdentifiers()
        CFShow("des:\(myDesTypes)")
        let gifUrl = NSBundle.mainBundle().URLForResource("Preloader", withExtension: "gif")
        let gifData = NSData(contentsOfURL: gifUrl!)
        let imageSource = CGImageSourceCreateWithData(gifData!, nil)
        let count = CGImageSourceGetCount(imageSource!)
        var images:Array<CGImage> = []
        var keys = [unsafeAddressOf(kCGImageSourceThumbnailMaxPixelSize)]
        var values = [unsafeAddressOf(200)]
        var keyCall = kCFTypeDictionaryKeyCallBacks
        var valCall = kCFTypeDictionaryValueCallBacks
        let dict = CFDictionaryCreate(kCFAllocatorDefault, &keys, &values, 1, &keyCall, &valCall)
        print("所有属性：\(CGImageSourceCopyProperties(imageSource!, nil))")
//        print("所有属性(带字典)：\(CGImageSourceCopyProperties(imageSource!, dict))")
        for index in 0..<count {
            images.append(CGImageSourceCreateImageAtIndex(imageSource!, index, dict)!)
            let propers = CGImageSourceCopyPropertiesAtIndex(imageSource!, index, dict)
            
            let thumImg = CGImageSourceCreateThumbnailAtIndex(imageSource!, index, dict)
            print("每张图片属性：\(thumImg)")
        }