题记
如我们iOS开发者所知，目前iOS还没有支持原生展现GIF图片，因此合成和分解GIF图片对于我们处理各种动画效果有着很高的使用价值。话不多说先看看效果图：
- 这里提供了3个按钮，本质上是两个方法，分解与合成GIF，因为只要有这两个方法的存在，无论我们拿到的是GIF图还是帧图，我们都能简单地在我们的设备上播放GIF。
代码
- 分解GIF
/// 把gif动图分解成每一帧图片
///
/// - Parameters:
/// - imageType: 分解后的图片格式
/// - path: gif路径
/// - locatioin: 分解后图片保存路径（如果为空则保存在默认路径）
/// - imageName: 分解后图片名称
func decompositionImage( _ imageType: imageType, _ path: String, _ locatioin: String = "", _ imageName: String = "") {
//把图片转成data
let gifDate = try! Data(contentsOf: URL(fileURLWithPath: path))
guard let gifSource = CGImageSourceCreateWithData(gifDate as CFData, nil) else { return }
//计算图片张数
let count = CGImageSourceGetCount(gifSource)
var dosc: [String] = []
var directory = ""
//判断是否传入路径，如果没有则使用默认路径
if locatioin.isEmpty {
dosc = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)
directory = dosc[0] + "/"
}else{
let index = locatioin.index(locatioin.endIndex, offsetBy: -1)
if locatioin.substring(from: index) != "/" {
directory = locatioin + "/"
}else{
directory = locatioin
}
}
var imagePath = ""
//逐一取出
for i in 0...count-1 {
guard let imageRef = CGImageSourceCreateImageAtIndex(gifSource, i, nil) else { return }
let image = UIImage(cgImage: imageRef, scale: UIScreen.main.scale, orientation: .up)
//根据选择不同格式生成对应图片已经路径
switch imageType {
case .jpg:
guard let imageData = UIImageJPEGRepresentation(image, 1) else { return }
if imageName.isEmpty {
imagePath = directory + "\(i)" + ".jpg"
}else {
imagePath = directory + "\(imageName)" + "\(i)" + ".jpg"
}
try? imageData.write(to: URL.init(fileURLWithPath: imagePath), options: .atomic)
case .png:
guard let imageData = UIImagePNGRepresentation(image) else { return }
if imageName.isEmpty {
imagePath = directory + "\(i)" + ".png"
}else {
imagePath = directory + "\(imageName)" + "\(i)" + ".png"
}
//生成图片
try? imageData.write(to: URL.init(fileURLWithPath: imagePath), options: .atomic)
}
print(imagePath)
}
}
- 合成GIF
/// 根据传入图片数组创建gif动图
///
/// - Parameters:
/// - images: 源图片数组
/// - imageName: 生成gif图片名称
/// - imageCuont: 图片总数量
func compositionImage(_ images: NSMutableArray, _ imageName: String, _ imageCuont: Int) {
//在Document目录下创建gif文件
let docs = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)
let gifPath = docs[0] + "/\(imageName)" + ".gif"
guard let url = CFURLCreateWithFileSystemPath(kCFAllocatorDefault, gifPath as CFString, .cfurlposixPathStyle, false), let destinaiton = CGImageDestinationCreateWithURL(url, kUTTypeGIF, imageCuont, nil) else { return }
//设置每帧图片播放时间
let cgimageDic = [kCGImagePropertyGIFDelayTime as String: 0.1]
let gifDestinaitonDic = [kCGImagePropertyGIFDictionary as String: cgimageDic]
//添加gif图像的每一帧元素
for cgimage in images {
CGImageDestinationAddImage(destinaiton, (cgimage as AnyObject).cgImage!!, gifDestinaitonDic as CFDictionary)
}
// 设置gif的彩色空间格式、颜色深度、执行次数
let gifPropertyDic = NSMutableDictionary()
gifPropertyDic.setValue(kCGImagePropertyColorModelRGB, forKey: kCGImagePropertyColorModel as String)
gifPropertyDic.setValue(16, forKey: kCGImagePropertyDepth as String)
gifPropertyDic.setValue(1, forKey: kCGImagePropertyGIFLoopCount as String)
//设置gif属性
let gifDicDest = [kCGImagePropertyGIFDictionary as String: gifPropertyDic]
CGImageDestinationSetProperties(destinaiton, gifDicDest as CFDictionary)
//生成gif
CGImageDestinationFinalize(destinaiton)
print(gifPath)
}
- 播放
- 这里继承UIImageView定义了一个JJGIFImageView类，增加了一个直接显示GIF图片的方法，只需要把GIF的路径传入，设置GIF时间以及重复次数即可
class JJGIFImageView: UIImageView {
var images: [UIImage] = []
/// GIF图片展示
///
/// - Parameters:
/// - path: GIF所在路径
/// - duration: 持续时间
/// - repeatCount: 重复次数
public func presentationGIFImage(path: String, duration: TimeInterval, repeatCount: Int) {
decompositionImage(path)
displayGIF(duration, repeatCount)
}
private func decompositionImage(_ path: String) {
//把图片转成data
let gifDate = try! Data(contentsOf: URL(fileURLWithPath: path))
guard let gifSource = CGImageSourceCreateWithData(gifDate as CFData, nil) else { return }
//计算图片张数
let count = CGImageSourceGetCount(gifSource)
//把每一帧图片拼接到数组
for i in 0...count-1 {
guard let imageRef = CGImageSourceCreateImageAtIndex(gifSource, i, nil) else { return }
let image = UIImage(cgImage: imageRef, scale: UIScreen.main.scale, orientation: .up)
images.append(image)
}
}
private func displayGIF(_ duration: TimeInterval, _ repeatCount: Int) {
self.animationImages = images
self.animationDuration = duration
self.animationRepeatCount = repeatCount
self.startAnimating()
}
}
