一些UIImage扩展
压缩图片
/// compress 这个方法显然还不是最优解（耗时较长，有一瞬间的内存暴涨，存在闪退隐患），还需要优化
class func compress(_ data: Data, maxSize: CGSize? = CGSize(width: 600, height: 600), maxKB: CGFloat? = 100) -> UIImage? {
if let image = UIImage(data: data) {
return compress(image, maxSize: maxSize, maxKB: maxKB)
}return nil
}class func compress(_ image: UIImage, maxSize: CGSize? = CGSize(width: 600, height: 600), maxKB: CGFloat? = 100) -> UIImage? {
if let data = image.resizeImage(maxSize: maxSize)?.resizeImageData(maxKB: maxKB) {
return UIImage(data: data)
}
return image
}class func compress(_ image: UIImage, maxSize: CGSize? = CGSize(width: 600, height: 600), maxKB: CGFloat? = 100) -> Data? {
if let data = image.jpegData(compressionQuality: 1.0) {
if let img = UIImage(data: data, scale: 1.0) {
return img.resizeImage(maxSize: maxSize)?.resizeImageData(maxKB: maxKB)
}
}return nil
}class func compress(onlySize data: Data, maxSize: CGSize? = CGSize(width: 600, height: 600)) -> UIImage? {
if let image = UIImage(data: data) {
return image.resizeImage(maxSize: maxSize)
}return nil
}class func compress(onlyDataSize data: Data, maxKB: CGFloat? = 100) -> UIImage? {
if let image = UIImage(data: data) {
if let d = image.resizeImageData(maxKB: maxKB) {
return UIImage(data: d)
}else {
return image
}
}return nil
}func resizeImage(maxSize: CGSize? = CGSize(width: 600, height: 600)) -> UIImage? {
return autoreleasepool { () -> UIImage? in
var re_size = self.sizelet width_scale: CGFloat = re_size.width / maxSize!.width
let height_scale: CGFloat = re_size.height / maxSize!.heightif width_scale > 1.0 && width_scale > height_scale {
re_size = CGSize(width: self.size.width / width_scale, height: self.size.height / width_scale)
}else if height_scale > 1.0 && height_scale > width_scale {
re_size = CGSize(width: self.size.width / height_scale, height: self.size.height / height_scale)
}UIGraphicsBeginImageContextWithOptions(re_size, false, UIScreen.main.scale)
self.draw(in: CGRect(origin: .zero, size: re_size))
let newImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()return newImage
}
}func resizeImageData(maxKB: CGFloat? = 100) -> Data? {
return autoreleasepool { () -> Data? in
if let data = https://www.it610.com/article/self.jpegData(compressionQuality: 1.0) {
let size = CGFloat(data.count) / 1024.0 / maxKB!
let rate: CGFloat = (size> 1) ? (1 / (size + 1.0)) : 1.0
let imageData = https://www.it610.com/article/self.jpegData(compressionQuality: rate)print("- resizeImage - jpeg", data, "->", imageData ?? "0", "is main thread:", Thread.current.isMainThread)return imageData
}else {
//print("- resizeImage - can not to jpeg", newImage ?? "no image")
}return nil
}
}/// io_compress 这个方法 速度快，内存消耗小，压缩狠(清晰度不够)，压缩的方向会有问题，需要调整图片方向
class func io_compress(_ data: Data, _ orientation: UIImage.Orientation, maxImageSize: CGSize? = nil) -> UIImage? {
return autoreleasepool { () -> UIImage? in
if let source = CGImageSourceCreateWithData(data as CFData, nil) {
let maxSize: CGSize = maxImageSize ?? UIScreen.main.bounds.sizelet options: [CFString : Any] = [
kCGImageSourceCreateThumbnailFromImageIfAbsent: true,
kCGImageSourceThumbnailMaxPixelSize: max(maxSize.width, maxSize.height)
]if let cgImage = CGImageSourceCreateThumbnailAtIndex(source, 0, options as CFDictionary) {
let newImage = UIImage(cgImage: cgImage, scale: 1.0, orientation: orientation)
return newImage.fixImageOrientation()
}
}return nil
}
}
///图片方向矫正
func fixImageOrientation() -> UIImage {
if self.imageOrientation == .up {
return self
}let size = self.size
var transform: CGAffineTransform = CGAffineTransform.identityswitch self.imageOrientation {
case .left, .leftMirrored:
transform = transform.translatedBy(x: size.width, y: 0)
transform = transform.rotated(by: CGFloat.pi / 2)
case .down, .downMirrored:
transform = transform.translatedBy(x: size.width, y: size.height)
transform = transform.rotated(by: CGFloat.pi)
case .right, .rightMirrored:
transform = transform.translatedBy(x: 0, y: size.height)
transform = transform.rotated(by: -CGFloat.pi / 2)
default:break
}switch self.imageOrientation {
case .upMirrored, .downMirrored:
transform = transform.translatedBy(x: size.width, y: 0)
transform = transform.scaledBy(x: -1, y: 1)
case .leftMirrored, .rightMirrored:
transform = transform.translatedBy(x: size.height, y: 0)
transform = transform.scaledBy(x: -1, y: 1)
default:break
}guard let cg_image = self.cgImage else {return self}
guard let cg_colorSpace = cg_image.colorSpace else {return self}guard let context = CGContext(data: nil,
width: Int(size.width),
height: Int(size.height),
bitsPerComponent: cg_image.bitsPerComponent,
bytesPerRow: 0,
space: cg_colorSpace,
bitmapInfo: cg_image.bitmapInfo.rawValue) else {return self}context.concatenate(transform)switch self.imageOrientation {
case .left, .leftMirrored, .right, .rightMirrored:
context.draw(cg_image, in: CGRect(x: 0, y: 0, width: size.height, height: size.width))
default:
context.draw(cg_image, in: CGRect(x: 0, y: 0, width: size.width, height: size.height))
}guard let cgImg = context.makeImage() else {return self}return UIImage(cgImage: cgImg)
}
重设图片大小
func reSizeImage(_ reSize: CGSize) -> UIImage? {
//UIGraphicsBeginImageContext(reSize);
UIGraphicsBeginImageContextWithOptions(reSize,false,UIScreen.main.scale)
self.draw(in: CGRect(x: 0, y: 0, width: reSize.width, height: reSize.height))
guard let reSizeImage: UIImage = UIGraphicsGetImageFromCurrentImageContext() else {return nil}
UIGraphicsEndImageContext()
return reSizeImage
}
等比率缩放（依赖于重设图片大小方法）
func scaleImage(_ scale: CGFloat) -> UIImage? {
let reSize = CGSize(width: self.size.width * scale, height: self.size.height * scale)
return reSizeImage(reSize)
}
裁剪
func cutImage(_ rect: CGRect) -> UIImage? {
guard let cgImage = self.cgImage?.cropping(to: rect) else {return nil}return UIImage(cgImage: cgImage)
}func cutImageWidth(_ widthScale: CGFloat) -> UIImage? {
guard let cgImage = self.cgImage?.cropping(to: CGRect(x: 0, y: 0, width: self.size.width * widthScale, height: self.size.height)) else {return nil}return UIImage(cgImage: cgImage)
}
合成
func composeImageWith(_ image: UIImage) -> UIImage? {
UIGraphicsBeginImageContextWithOptions(self.size,false,UIScreen.main.scale)
self.draw(in: CGRect(origin: CGPoint.zero, size: self.size))
image.draw(in: CGRect(origin: CGPoint.zero, size: image.size))
guard let reSizeImage: UIImage = UIGraphicsGetImageFromCurrentImageContext() else {return nil}
UIGraphicsEndImageContext()return reSizeImage
}
简单渲染
func apply(_ color: UIColor, _ imageView: UIImageView) -> UIImage? {
imageView.tintColor = color
return self.withRenderingMode(.alwaysTemplate)
}
GIF
//通过data获取gif source//
class func getGifSource(_ data: Data) -> UIImageView.GIFSource? {
if let source = CGImageSourceCreateWithData(data as CFData, nil) {
var images = [UIImage]()
var duration: TimeInterval = 0
for i in 0.. UIImageView.GIFSource? {
if let url = URL(string: imagePath) {
do {
let data = https://www.it610.com/article/try Data(contentsOf: url)return UIImage.getGifSource(data)
}catch {
print(error)
}
}return nil
}//以下是UIImageView的扩展（用于展示GIF图片）
typealias GIFSource = ([UIImage], TimeInterval)func showGif(_ gifSource: GIFSource?) {
guard let source = gifSource else {return}
self.animationImages = source.0
self.animationDuration = source.1
self.animationRepeatCount = 0self.startAnimating()
}
添加水印
func waterMark(_ text: String) -> UIImage? {
let text_width: CGFloat = self.size.width / 3
var font_size: Int = 10
var merge: CGFloat = 20
var standard_w: CGFloat = 0for i in font_size..<100 {
let dic = [NSAttributedString.Key.font: UIFont.systemFont(ofSize: CGFloat(i))]
let size = text.size(withAttributes: dic)if i == font_size {
standard_w = size.width
}if size.width >= text_width {
font_size = i
merge = merge * (size.width / standard_w)
break
}
}UIGraphicsBeginImageContext(self.size)
self.draw(in: CGRect(origin: .zero, size: self.size))let style = NSMutableParagraphStyle()
style.lineBreakMode = .byWordWrapping
style.alignment = .centerlet attrDic = [
NSAttributedString.Key.font: UIFont.systemFont(ofSize: CGFloat(font_size)),
NSAttributedString.Key.foregroundColor: UIColor.darkText,
NSAttributedString.Key.paragraphStyle: style,
NSAttributedString.Key.backgroundColor: UIColor(white: 1, alpha: 0.3)
]let text_size = text.size(withAttributes: attrDic)
let rect = CGRect(x: merge, y: self.size.height - merge - text_size.height, width: text_size.width, height: text_size.height) // 左下角text.draw(in: rect, withAttributes: attrDic)
let image = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()return image
}推荐阅读
- 今天写一些什么
- 「按键精灵安卓版」关于全分辨率脚本的一些理解（非游戏app）
- 一些杂感（11）
- 记录iOS生成分享图片的一些问题，根据UIView生成固定尺寸的分享图片
- 一些小日子
- 一些喜欢的句子
- 关于this的一些问题（1）
- 多给孩子一些耐心的陪伴吧
- 机器学习一些简单笔记
- 【无戒学堂】一些大问题?|【无戒学堂】一些大问题? 01