//
//  UIImage+Extension.m
//  HuaKaiChat
//
//  Created by BigBiao on 2017/9/16.
//  Copyright © 2017年 huakai. All rights reserved.
//

#import "UIImage+Extension.h"
#import <AVFoundation/AVFoundation.h>
#import <Accelerate/Accelerate.h>
#import <float.h>


#define AspectRatio  1.0
#define AspectRatioDT  1.0
@implementation UIImage (Extension)
- (UIImage*)imageWithSize:(CGSize)size cornerRadius:(CGFloat)corner rectCornerType:(UIRectCorner)cornerType{
    // 传入的View.frame.size是0的话，直接返回nil，防止 UIGraphicsBeginImageContext() 传入0，导致崩溃
    if (CGSizeEqualToSize(size, CGSizeZero)) {
        return nil;
    }
    UIGraphicsBeginImageContext(size);
    if (!UIGraphicsGetCurrentContext()) {
        return nil;
    }
    UIBezierPath* path = [UIBezierPath bezierPathWithRoundedRect:CGRectMake(0, 0, size.width, size.height) byRoundingCorners:cornerType cornerRadii:CGSizeMake(corner, corner)];
    [path addClip];
    [(UIImage*)self drawInRect:CGRectMake(0, 0, size.width, size.height)];
    UIImage* newImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    
    return newImage;
}
+ (UIImage *)screenshot
{
    
    CGSize imageSize = [[UIScreen mainScreen] bounds].size;
    // 传入的View.frame.size是0的话，直接返回nil，防止 UIGraphicsBeginImageContext() 传入0，导致崩溃
    if (CGSizeEqualToSize(imageSize, CGSizeZero)) {
        return nil;
    }
    if (NULL != UIGraphicsBeginImageContextWithOptions) {
        UIGraphicsBeginImageContextWithOptions(imageSize, NO, 0);
    } else {
        UIGraphicsBeginImageContext(imageSize);
    }
    
    CGContextRef context = UIGraphicsGetCurrentContext();
    
    for (UIWindow *window in [[UIApplication sharedApplication] windows]) {
        if (![window respondsToSelector:@selector(screen)] || [window screen] == [UIScreen mainScreen]) {
            CGContextSaveGState(context);
            
            CGContextTranslateCTM(context, [window center].x, [window center].y);
            
            CGContextConcatCTM(context, [window transform]);
            
            CGContextTranslateCTM(context,
                                  -[window bounds].size.width * [[window layer] anchorPoint].x,
                                  -[window bounds].size.height * [[window layer] anchorPoint].y);
            
            [[window layer] renderInContext:context];
            
            CGContextRestoreGState(context);
        }
    }
    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
    
    UIGraphicsEndImageContext();
    
    return image;
}
+ (UIImage *)cutImage:(UIImage*)image isDT:(BOOL)flag
{
    //压缩图片
    CGSize newSize;
    CGFloat padHeight;
    CGImageRef imageRef = nil;
    newSize.width = image.size.width;
    if (flag) {
        newSize.height = newSize.width*AspectRatioDT;
        padHeight = (image.size.height-image.size.width*AspectRatioDT)/2;
    }else{
        newSize.height = newSize.width*AspectRatio;
        padHeight = (image.size.height-image.size.width*AspectRatio)/2;
    }
    
    imageRef = CGImageCreateWithImageInRect([image CGImage], CGRectMake(0, padHeight, newSize.width, newSize.height));
    
    return [UIImage imageWithCGImage:imageRef];
}
+ (UIImage *)imageWithVideo:(NSURL *)videoURL
{
    AVURLAsset *asset = [[AVURLAsset alloc] initWithURL:videoURL options:nil];
    
    AVAssetImageGenerator* gen = [[AVAssetImageGenerator alloc] initWithAsset: asset];
    
    gen.appliesPreferredTrackTransform = YES;
    gen.apertureMode = AVAssetImageGeneratorApertureModeEncodedPixels;
    
    CMTime time = CMTimeMake(0, 2);
    
    NSError *error = nil;
    
    CMTime actualTime;
    
    CGImageRef  image = [gen  copyCGImageAtTime: time actualTime: &actualTime error:&error];
    
    UIImage *thumb = [[UIImage alloc] initWithCGImage: image];
    
    CGImageRelease(image);
    
    return  thumb;
    
}
+ (UIImage *)imageWithColor:(UIColor *)color size:(CGSize)size
{
    CGRect rect = CGRectMake(0, 0, size.width, size.height);
    // 传入的View.frame.size是0的话，直接返回nil，防止 UIGraphicsBeginImageContext() 传入0，导致崩溃
    if (CGSizeEqualToSize(rect.size, CGSizeZero)) {
        return nil;
    }
    UIGraphicsBeginImageContext(rect.size);
    CGContextRef context = UIGraphicsGetCurrentContext();
    CGContextSetFillColorWithColor(context,color.CGColor);
    CGContextFillRect(context, rect);
    UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    
    return img;
}
- (UIImage *)imageByApplyingAlpha:(CGFloat)alpha{
    // 传入的View.frame.size是0的话，直接返回nil，防止 UIGraphicsBeginImageContext() 传入0，导致崩溃
    if (CGSizeEqualToSize(self.size, CGSizeZero)) {
        return nil;
    }
    UIGraphicsBeginImageContextWithOptions(self.size, NO, 0.0f);
    CGContextRef ctx = UIGraphicsGetCurrentContext();
    CGRect area = CGRectMake(0, 0, self.size.width, self.size.height);
    CGContextScaleCTM(ctx, 1, -1);
    CGContextTranslateCTM(ctx, 0, -area.size.height);
    CGContextSetBlendMode(ctx, kCGBlendModeMultiply);
    CGContextSetAlpha(ctx, alpha);
    CGContextDrawImage(ctx, area, self.CGImage);
    UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return newImage;
    
}

+ (instancetype)waterImageWithBg:(UIImage*)bgImg centerImg:(NSString *)centerImg
{
    UIGraphicsBeginImageContextWithOptions(CGSizeMake((KScreenWidth-20)/2, (KScreenWidth-20)/2), NO, 0.0);
    [bgImg drawInRect:CGRectMake(0, 0,(KScreenWidth-20)/2, (KScreenWidth-20)/2)];
    
    //要绘制的内容
    //1.绘制灰色背景
    UIImage* grayImage = [UIImage imageWithColor:DecColorFromRGBA(0, 0, 0,0) size:bgImg.size];
    [grayImage drawInRect:CGRectMake(0, 0, (KScreenWidth-20)/2, (KScreenWidth-20)/2)];
    //2.绘制文字
    //    NSString* str =@"免费现场预览";
    //    [str drawInRect:CGRectMake(KScreenWidth/3,KScreenWidth*AspectRatio/2-10 ,KScreenWidth/3-30, 40) withAttributes:@{NSFontAttributeName:[UIFont systemFontOfSize:15],NSForegroundColorAttributeName:[UIColor whiteColor]}];
    //3.绘制播放按钮
    UIImage* img = [[UIImage imageNamed:centerImg] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];
    //    [img drawInRect:CGRectMake((KScreenWidth-img.size.width)/2,KScreenWidth*AspectRatio/2-15,img.size.width,img.size.height )];
    [img drawAtPoint:CGPointMake((KScreenWidth-20)/4-img.size.width/2, (KScreenWidth-20)/4-img.size.height/2)];
    //    [img drawInRect:CGRectMake(0, 0, img.size.width, img.size.height)];
    
    UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return newImage;
}

+ (UIImage*)screenView:(UIView *)view{
    CGRect rect = view.frame;
    // 传入的View.frame.size是0的话，直接返回nil，防止 UIGraphicsBeginImageContext() 传入0，导致崩溃
    if (CGSizeEqualToSize(rect.size, CGSizeZero)) {
        return nil;
    }
    UIGraphicsBeginImageContext(rect.size);
    CGContextRef context = UIGraphicsGetCurrentContext();
    [view.layer renderInContext:context];
    //add by leo
    [view  drawViewHierarchyInRect: view.frame  afterScreenUpdates:YES];
    UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return img;
}

//图片压缩到指定大小1280*1280内
- (UIImage*)imageByScalingAndCroppingForSize:(CGSize)targetSize
{
    UIImage *sourceImage = self;
    UIImage *newImage = nil;
    CGSize imageSize = sourceImage.size;
    CGFloat width = imageSize.width;
    CGFloat height = imageSize.height;
    CGFloat targetWidth = targetSize.width;
    CGFloat targetHeight = targetSize.height;
    CGFloat scaleFactor = 0.0;
    CGFloat scaledWidth = targetWidth;
    CGFloat scaledHeight = targetHeight;
    CGPoint thumbnailPoint = CGPointMake(0.0,0.0);
    
    if (CGSizeEqualToSize(imageSize, targetSize) == NO)
    {
        CGFloat widthFactor = targetWidth / width;
        CGFloat heightFactor = targetHeight / height;
        
        if (widthFactor > heightFactor)
            scaleFactor = widthFactor; // scale to fit height
        else
            scaleFactor = heightFactor; // scale to fit width
        scaledWidth= width * scaleFactor;
        scaledHeight = height * scaleFactor;
        
        // center the image
        if (widthFactor > heightFactor)
        {
            thumbnailPoint.y = (targetHeight - scaledHeight) * 0.5;
        }
        else if (widthFactor < heightFactor)
        {
            thumbnailPoint.x = (targetWidth - scaledWidth) * 0.5;
        }
    }
    // 传入的View.frame.size是0的话，直接返回nil，防止 UIGraphicsBeginImageContext() 传入0，导致崩溃
    if (CGSizeEqualToSize(targetSize, CGSizeZero)) {
        return nil;
    }
    UIGraphicsBeginImageContext(targetSize); // this will crop
    
    CGRect thumbnailRect = CGRectZero;
    thumbnailRect.origin = thumbnailPoint;
    thumbnailRect.size.width= scaledWidth;
    thumbnailRect.size.height = scaledHeight;
    
    [sourceImage drawInRect:thumbnailRect];
    
    newImage = UIGraphicsGetImageFromCurrentImageContext();
    if(newImage == nil)
        NSLog(@"could not scale image");
    
    //pop the context to get back to the default
    UIGraphicsEndImageContext();
    return newImage;
}
//循环压缩图片到制定大小
//循环压缩图片到制定大小
- (NSData *)compressImageToMaxFileSize:(NSInteger)maxFileSize {
    CGFloat compression = 1.0f;
    CGFloat maxCompression = 0.01f;
    NSData *imageData = UIImageJPEGRepresentation(self, compression);
    NSLog(@"%lu",imageData.length);
    while ([imageData length] > maxFileSize && compression > maxCompression) {
        compression -= 0.01;
        imageData = UIImageJPEGRepresentation(self, compression);
    }
    
    return imageData;
}
+ (NSData *)zipGiFWithAsset:(PHAsset*)asset{
    NSArray *resourceList = [PHAssetResource assetResourcesForAsset:asset];
    [resourceList enumerateObjectsUsingBlock:^(id  _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
        PHAssetResource *resource = obj;
        PHAssetResourceRequestOptions *option = [[PHAssetResourceRequestOptions alloc]init];
        option.networkAccessAllowed = YES;
        if ([resource.uniformTypeIdentifier isEqualToString:@"com.compuserve.gif"]) {
            NSLog(@"gif大爷");
            // 首先,需要获取沙盒路径
            NSString *path = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject];
            // 拼接图片名为resource.originalFilename的路径
            NSString *imageFilePath = [path stringByAppendingPathComponent:resource.originalFilename];
            __block NSData *data = [[NSData alloc]init];
            [[PHAssetResourceManager defaultManager] writeDataForAssetResource:resource toFile:[NSURL fileURLWithPath:imageFilePath]  options:option completionHandler:^(NSError * _Nullable error) {
                if (error) {
                    NSLog(@"error:%@",error);
                    if(error.code == -1){//文件已存在
                        data = [NSData dataWithContentsOfURL:[NSURL fileURLWithPath:imageFilePath]];
                    }
                    //NSLog(@"data%@",data);
                   
                } else {
                    data = [NSData dataWithContentsOfURL:[NSURL fileURLWithPath:imageFilePath]];
                    //NSLog(@"data%@",data);
                }
            }];
            
        }else{
            NSLog(@"jepg大爷");
        }
    }];
    return nil;
}

+ (NSData *)zipGIFWithData:(NSData *)data {
//    if (!data) {
//        return nil;
//    }
//    CGImageSourceRef source = CGImageSourceCreateWithData((__bridge CFDataRef)data, NULL);
//    size_t count = CGImageSourceGetCount(source);
//    UIImage *animatedImage = nil;
//    NSMutableArray *images = [NSMutableArray array];
//    NSTimeInterval duration = 0.0f;
//    for (size_t i = 0; i < count; i++) {
//        CGImageRef image = CGImageSourceCreateImageAtIndex(source, i, NULL);
//        duration += [self frameDurationAtIndex:i source:source];
//        UIImage *ima = [UIImage imageWithCGImage:image scale:[UIScreen mainScreen].scale orientation:UIImageOrientationUp];
//        ima = [ima zip];
//        [images addObject:ima];
//        CGImageRelease(image);
//        if (!duration) {
//            duration = (1.0f / 10.0f) * count;
//        }
//        animatedImage = [UIImage animatedImageWithImages:images duration:duration];
//    }
//    CFRelease(source);
//    return UIImagePNGRepresentation(animatedImage);
    return nil;
}

+(NSData *)zipNSDataWithImage:(UIImage *)sourceImage maxFileSize:(NSInteger)maxFileSize {
    //进行图像尺寸的压缩
    CGSize imageSize = sourceImage.size;//取出要压缩的image尺寸
    CGFloat width = imageSize.width;    //图片宽度
    CGFloat height = imageSize.height;  //图片高度
    //1.宽高大于1280(宽高比不按照2来算，按照1来算)
    if (width>1280) {
        if (width>height) {
            CGFloat scale = width/height;
            height = 1280;
            width = height*scale;
        }else{
            CGFloat scale = height/width;
            width = 1280;
            height = width*scale;
        }
        //2.高度大于1280
    }else if(height>1280){
        CGFloat scale = height/width;
        width = 1280;
        height = width*scale;
    }else{
    }
    // 传入的View.frame.size是0的话，直接返回nil，防止 UIGraphicsBeginImageContext() 传入0，导致崩溃
    if (CGSizeEqualToSize(imageSize, CGSizeZero)) {
        return nil;
    }
    UIGraphicsBeginImageContext(CGSizeMake(width, height));
    if (sourceImage) {
        [sourceImage drawInRect:CGRectMake(0,0,width,height)];
    }
    UIImage* newImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    
    return [newImage compressImageToMaxFileSize:maxFileSize];//200KB
    
}
@end


@implementation UIImage (ImageEffects)


- (UIImage *)applyLightEffect
{
    UIColor *tintColor = [UIColor colorWithWhite:1.0 alpha:0.3];
    return [self applyBlurWithRadius:30 tintColor:tintColor saturationDeltaFactor:1.8 maskImage:nil];
}


- (UIImage *)applyExtraLightEffect
{
    UIColor *tintColor = [UIColor colorWithWhite:0.97 alpha:0.82];
    return [self applyBlurWithRadius:20 tintColor:tintColor saturationDeltaFactor:1.8 maskImage:nil];
}


- (UIImage *)applyDarkEffect
{
    UIColor *tintColor = DecColorFromRGBA(79, 66, 81, 0.8);
    return [self applyBlurWithRadius:20 tintColor:tintColor saturationDeltaFactor:1.8 maskImage:nil];
}


- (UIImage *)applyTintEffectWithColor:(UIColor *)tintColor
{
    const CGFloat EffectColorAlpha = 0.6;
    UIColor *effectColor = tintColor;
    long int componentCount = CGColorGetNumberOfComponents(tintColor.CGColor);
    if (componentCount == 2) {
        CGFloat b;
        if ([tintColor getWhite:&b alpha:NULL]) {
            effectColor = [UIColor colorWithWhite:b alpha:EffectColorAlpha];
        }
    }
    else {
        CGFloat r, g, b;
        if ([tintColor getRed:&r green:&g blue:&b alpha:NULL]) {
            effectColor = [UIColor colorWithRed:r green:g blue:b alpha:EffectColorAlpha];
        }
    }
    return [self applyBlurWithRadius:10 tintColor:effectColor saturationDeltaFactor:-1.0 maskImage:nil];
}


- (UIImage *)applyBlurWithRadius:(CGFloat)blurRadius tintColor:(UIColor *)tintColor saturationDeltaFactor:(CGFloat)saturationDeltaFactor maskImage:(UIImage *)maskImage
{
    // Check pre-conditions.
    if (self.size.width < 1 || self.size.height < 1) {
        NSLog (@"*** error: invalid size: (%.2f x %.2f). Both dimensions must be >= 1: %@", self.size.width, self.size.height, self);
        return nil;
    }
    if (!self.CGImage) {
        NSLog (@"*** error: image must be backed by a CGImage: %@", self);
        return nil;
    }
    if (maskImage && !maskImage.CGImage) {
        NSLog (@"*** error: maskImage must be backed by a CGImage: %@", maskImage);
        return nil;
    }
    
    CGRect imageRect = { CGPointZero, self.size };
    UIImage *effectImage = self;
    
    BOOL hasBlur = blurRadius > __FLT_EPSILON__;
    BOOL hasSaturationChange = fabs(saturationDeltaFactor - 1.) > __FLT_EPSILON__;
    if (hasBlur || hasSaturationChange) {
        // 传入的View.frame.size是0的话，直接返回nil，防止 UIGraphicsBeginImageContext() 传入0，导致崩溃
        if (CGSizeEqualToSize(self.size, CGSizeZero)) {
            return nil;
        }
        UIGraphicsBeginImageContextWithOptions(self.size, NO, [[UIScreen mainScreen] scale]);
        CGContextRef effectInContext = UIGraphicsGetCurrentContext();
        CGContextScaleCTM(effectInContext, 1.0, -1.0);
        CGContextTranslateCTM(effectInContext, 0, -self.size.height);
        CGContextDrawImage(effectInContext, imageRect, self.CGImage);
        
        vImage_Buffer effectInBuffer;
        effectInBuffer.data     = CGBitmapContextGetData(effectInContext);
        effectInBuffer.width    = CGBitmapContextGetWidth(effectInContext);
        effectInBuffer.height   = CGBitmapContextGetHeight(effectInContext);
        effectInBuffer.rowBytes = CGBitmapContextGetBytesPerRow(effectInContext);
        
        UIGraphicsBeginImageContextWithOptions(self.size, NO, [[UIScreen mainScreen] scale]);
        CGContextRef effectOutContext = UIGraphicsGetCurrentContext();
        vImage_Buffer effectOutBuffer;
        effectOutBuffer.data     = CGBitmapContextGetData(effectOutContext);
        effectOutBuffer.width    = CGBitmapContextGetWidth(effectOutContext);
        effectOutBuffer.height   = CGBitmapContextGetHeight(effectOutContext);
        effectOutBuffer.rowBytes = CGBitmapContextGetBytesPerRow(effectOutContext);
        
        if (hasBlur) {
            // A description of how to compute the box kernel width from the Gaussian
            // radius (aka standard deviation) appears in the SVG spec:
            // http://www.w3.org/TR/SVG/filters.html#feGaussianBlurElement
            //
            // For larger values of 's' (s >= 2.0), an approximation can be used: Three
            // successive box-blurs build a piece-wise quadratic convolution kernel, which
            // approximates the Gaussian kernel to within roughly 3%.
            //
            // let d = floor(s * 3*sqrt(2*pi)/4 + 0.5)
            //
            // ... if d is odd, use three box-blurs of size 'd', centered on the output pixel.
            //
            CGFloat inputRadius = blurRadius * [[UIScreen mainScreen] scale];
            int radius = floor(inputRadius * 3. * sqrt(2 * M_PI) / 4 + 0.5);
            if (radius % 2 != 1) {
                radius += 1; // force radius to be odd so that the three box-blur methodology works.
            }
            vImageBoxConvolve_ARGB8888(&effectInBuffer, &effectOutBuffer, NULL, 0, 0, radius, radius, 0, kvImageEdgeExtend);
            vImageBoxConvolve_ARGB8888(&effectOutBuffer, &effectInBuffer, NULL, 0, 0, radius, radius, 0, kvImageEdgeExtend);
            vImageBoxConvolve_ARGB8888(&effectInBuffer, &effectOutBuffer, NULL, 0, 0, radius, radius, 0, kvImageEdgeExtend);
        }
        BOOL effectImageBuffersAreSwapped = NO;
        if (hasSaturationChange) {
            CGFloat s = saturationDeltaFactor;
            CGFloat floatingPointSaturationMatrix[] = {
                0.0722 + 0.9278 * s,  0.0722 - 0.0722 * s,  0.0722 - 0.0722 * s,  0,
                0.7152 - 0.7152 * s,  0.7152 + 0.2848 * s,  0.7152 - 0.7152 * s,  0,
                0.2126 - 0.2126 * s,  0.2126 - 0.2126 * s,  0.2126 + 0.7873 * s,  0,
                0,                    0,                    0,  1,
            };
            const int32_t divisor = 256;
            NSUInteger matrixSize = sizeof(floatingPointSaturationMatrix)/sizeof(floatingPointSaturationMatrix[0]);
            int16_t saturationMatrix[matrixSize];
            for (NSUInteger i = 0; i < matrixSize; ++i) {
                saturationMatrix[i] = (int16_t)roundf(floatingPointSaturationMatrix[i] * divisor);
            }
            if (hasBlur) {
                vImageMatrixMultiply_ARGB8888(&effectOutBuffer, &effectInBuffer, saturationMatrix, divisor, NULL, NULL, kvImageNoFlags);
                effectImageBuffersAreSwapped = YES;
            }
            else {
                vImageMatrixMultiply_ARGB8888(&effectInBuffer, &effectOutBuffer, saturationMatrix, divisor, NULL, NULL, kvImageNoFlags);
            }
        }
        if (!effectImageBuffersAreSwapped)
            effectImage = UIGraphicsGetImageFromCurrentImageContext();
        UIGraphicsEndImageContext();
        
        if (effectImageBuffersAreSwapped)
            effectImage = UIGraphicsGetImageFromCurrentImageContext();
        UIGraphicsEndImageContext();
    }
    // 传入的View.frame.size是0的话，直接返回nil，防止 UIGraphicsBeginImageContext() 传入0，导致崩溃
    if (CGSizeEqualToSize(self.size, CGSizeZero)) {
        return nil;
    }
    // Set up output context.
    UIGraphicsBeginImageContextWithOptions(self.size, NO, [[UIScreen mainScreen] scale]);
    CGContextRef outputContext = UIGraphicsGetCurrentContext();
    CGContextScaleCTM(outputContext, 1.0, -1.0);
    CGContextTranslateCTM(outputContext, 0, -self.size.height);
    
    // Draw base image.
    CGContextDrawImage(outputContext, imageRect, self.CGImage);
    
    // Draw effect image.
    if (hasBlur) {
        CGContextSaveGState(outputContext);
        if (maskImage) {
            CGContextClipToMask(outputContext, imageRect, maskImage.CGImage);
        }
        CGContextDrawImage(outputContext, imageRect, effectImage.CGImage);
        CGContextRestoreGState(outputContext);
    }
    
    // Add in color tint.
    if (tintColor) {
        CGContextSaveGState(outputContext);
        CGContextSetFillColorWithColor(outputContext, tintColor.CGColor);
        CGContextFillRect(outputContext, imageRect);
        CGContextRestoreGState(outputContext);
    }
    
    // Output image is ready.
    UIImage *outputImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    
    return outputImage;
}

+ (UIImage *)imageWithScreenshot
{
    NSData   *imageData  =  [self  dataWithScreenshotInPNGFormat];
    return  [UIImage  imageWithData:imageData];
}

+  (NSData   *)dataWithScreenshotInPNGFormat
{
    CGSize  imageSize  =  CGSizeZero;
    UIInterfaceOrientation  orientation  =  [UIApplication  sharedApplication].statusBarOrientation;
    if  (UIInterfaceOrientationIsPortrait(orientation))
        imageSize  =  [UIScreen  mainScreen].bounds.size;
    else
        imageSize  =  CGSizeMake([UIScreen  mainScreen].bounds.size.height,  [UIScreen  mainScreen].bounds.size.width);
    
    // 传入的View.frame.size是0的话，直接返回nil，防止 UIGraphicsBeginImageContext() 传入0，导致崩溃
    if (CGSizeEqualToSize(imageSize, CGSizeZero)) {
        return nil;
    }
    UIGraphicsBeginImageContextWithOptions(imageSize,  NO,  0);
    CGContextRef  context  =  UIGraphicsGetCurrentContext();
    for  (UIWindow   *window  in  [[UIApplication  sharedApplication]  windows])
    {
        CGContextSaveGState(context);
        CGContextTranslateCTM(context,  window.center.x,  window.center.y);
        CGContextConcatCTM(context,  window.transform);
        CGContextTranslateCTM(context,  -window.bounds.size.width   *  window.layer.anchorPoint.x,  -window.bounds.size.height   *  window.layer.anchorPoint.y);
        if  (orientation  ==  UIInterfaceOrientationLandscapeLeft)
        {
            CGContextRotateCTM(context,  M_PI_2);
            CGContextTranslateCTM(context,  0,  -imageSize.width);
        }
        else  if  (orientation  ==  UIInterfaceOrientationLandscapeRight)
        {
            CGContextRotateCTM(context,  -M_PI_2);
            CGContextTranslateCTM(context,  -imageSize.height,  0);
        }  else  if  (orientation  ==  UIInterfaceOrientationPortraitUpsideDown)  {
            CGContextRotateCTM(context,  M_PI);
            CGContextTranslateCTM(context,  -imageSize.width,  -imageSize.height);
        }
        if  ([window  respondsToSelector:@selector(drawViewHierarchyInRect:afterScreenUpdates:)])
        {
            [window  drawViewHierarchyInRect:window.bounds  afterScreenUpdates:YES];
        }
        else
        {
            [window.layer  renderInContext:context];
        }
        CGContextRestoreGState(context);
    }
    
    UIImage   *image  =  UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    
    return  UIImagePNGRepresentation(image);
}

- (UIImage *)cutCircleImage {
    // 传入的View.frame.size是0的话，直接返回nil，防止 UIGraphicsBeginImageContext() 传入0，导致崩溃
    if (CGSizeEqualToSize(self.size, CGSizeZero)) {
        return nil;
    }
    //开始图片上下文
    UIGraphicsBeginImageContextWithOptions(self.size, NO, 0.0);
    // 获取上下文
    CGContextRef ctr = UIGraphicsGetCurrentContext();
    // 设置圆形
    CGRect rect = CGRectMake(0, 0, self.size.width, self.size.height);
    CGContextAddEllipseInRect(ctr, rect);
    // 裁剪
    CGContextClip(ctr);
    // 将图片画上去
    [self drawInRect:rect];
    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return image;
}

+(UIImage *)boxblurImage:(UIImage *)image withBlurNumber:(CGFloat)blur {
    if (blur < 0.f || blur > 1.f) {
        blur = 0.5f;
    }
    int boxSize = (int)(blur * 40);
    boxSize = boxSize - (boxSize % 2) + 1;
    
    CGImageRef img = image.CGImage;
    
    vImage_Buffer inBuffer, outBuffer;
    vImage_Error error;
    
    void *pixelBuffer;
    //从CGImage中获取数据
    CGDataProviderRef inProvider = CGImageGetDataProvider(img);
    CFDataRef inBitmapData = CGDataProviderCopyData(inProvider);
    //设置从CGImage获取对象的属性
    inBuffer.width = CGImageGetWidth(img);
    inBuffer.height = CGImageGetHeight(img);
    inBuffer.rowBytes = CGImageGetBytesPerRow(img);
    
    inBuffer.data = (void*)CFDataGetBytePtr(inBitmapData);
    
    pixelBuffer = malloc(CGImageGetBytesPerRow(img) *
                         CGImageGetHeight(img));
    
    if(pixelBuffer == NULL)
        NSLog(@"No pixelbuffer");
    
    outBuffer.data = pixelBuffer;
    outBuffer.width = CGImageGetWidth(img);
    outBuffer.height = CGImageGetHeight(img);
    outBuffer.rowBytes = CGImageGetBytesPerRow(img);
    
    error = vImageBoxConvolve_ARGB8888(&inBuffer, &outBuffer, NULL, 0, 0, boxSize, boxSize, NULL, kvImageEdgeExtend);
    
    if (error) {
        NSLog(@"error from convolution %ld", error);
    }
    
    CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
    CGContextRef ctx = CGBitmapContextCreate(
                                             outBuffer.data,
                                             outBuffer.width,
                                             outBuffer.height,
                                             8,
                                             outBuffer.rowBytes,
                                             colorSpace,
                                             kCGImageAlphaNoneSkipLast);
    CGImageRef imageRef = CGBitmapContextCreateImage (ctx);
    UIImage *returnImage = [UIImage imageWithCGImage:imageRef];
    
    //clean up
    CGContextRelease(ctx);
    CGColorSpaceRelease(colorSpace);
    
    free(pixelBuffer);
    CFRelease(inBitmapData);
    
    CGColorSpaceRelease(colorSpace);
    CGImageRelease(imageRef);
    
    return returnImage;
}

@end