TZImagePicker/TZImagePickerController/TZImageCropManager.m

//
//  TZImageCropManager.m
//  TZImagePickerController
//
//  Created by 谭真 on 2016/12/5.
//  Copyright © 2016年 谭真. All rights reserved.
//

#import "TZImageCropManager.h"
#import "UIView+Layout.h"
#import <ImageIO/ImageIO.h>
#import "TZImageManager.h"
#import "TZImagePickerController.h"

@implementation TZImageCropManager

/// 裁剪框背景的处理
+ (void)overlayClippingWithView:(UIView *)view cropRect:(CGRect)cropRect containerView:(UIView *)containerView needCircleCrop:(BOOL)needCircleCrop {
    UIBezierPath *path= [UIBezierPath bezierPathWithRect:[UIScreen mainScreen].bounds];
    CAShapeLayer *layer = [CAShapeLayer layer];
    if (needCircleCrop) { // 圆形裁剪框
        [path appendPath:[UIBezierPath bezierPathWithArcCenter:containerView.center radius:cropRect.size.width / 2 startAngle:0 endAngle: 2 * M_PI clockwise:NO]];
    } else { // 矩形裁剪框
        [path appendPath:[UIBezierPath bezierPathWithRect:cropRect]];
    }
    layer.path = path.CGPath;
    layer.fillRule = kCAFillRuleEvenOdd;
    layer.fillColor = [[UIColor blackColor] CGColor];
    layer.opacity = 0.5;
    [view.layer addSublayer:layer];
}

/// 获得裁剪后的图片
+ (UIImage *)cropImageView:(UIImageView *)imageView toRect:(CGRect)rect zoomScale:(double)zoomScale containerView:(UIView *)containerView {
    CGAffineTransform transform = CGAffineTransformIdentity;
    // 平移的处理
    CGRect imageViewRect = [imageView convertRect:imageView.bounds toView:containerView];
    CGPoint point = CGPointMake(imageViewRect.origin.x + imageViewRect.size.width / 2, imageViewRect.origin.y + imageViewRect.size.height / 2);
    CGFloat xMargin = containerView.tz_width - CGRectGetMaxX(rect) - rect.origin.x;
    CGPoint zeroPoint = CGPointMake((CGRectGetWidth(containerView.frame) - xMargin) / 2, containerView.center.y);
    CGPoint translation = CGPointMake(point.x - zeroPoint.x, point.y - zeroPoint.y);
    transform = CGAffineTransformTranslate(transform, translation.x, translation.y);
    // 缩放的处理
    transform = CGAffineTransformScale(transform, zoomScale, zoomScale);
    
    CGImageRef imageRef = [self newTransformedImage:transform
                                        sourceImage:imageView.image.CGImage
                                         sourceSize:imageView.image.size
                                        outputWidth:rect.size.width * [UIScreen mainScreen].scale
                                           cropSize:rect.size
                                      imageViewSize:imageView.frame.size];
    UIImage *cropedImage = [UIImage imageWithCGImage:imageRef];
    cropedImage = [[TZImageManager manager] fixOrientation:cropedImage];
    CGImageRelease(imageRef);
    return cropedImage;
}

+ (CGImageRef)newTransformedImage:(CGAffineTransform)transform sourceImage:(CGImageRef)sourceImage sourceSize:(CGSize)sourceSize  outputWidth:(CGFloat)outputWidth cropSize:(CGSize)cropSize imageViewSize:(CGSize)imageViewSize {
    CGImageRef source = [self newScaledImage:sourceImage toSize:sourceSize];
    
    CGFloat aspect = cropSize.height/cropSize.width;
    CGSize outputSize = CGSizeMake(outputWidth, outputWidth*aspect);
    
    CGContextRef context = CGBitmapContextCreate(NULL, outputSize.width, outputSize.height, CGImageGetBitsPerComponent(source), 0, CGImageGetColorSpace(source), CGImageGetBitmapInfo(source));
    CGContextSetFillColorWithColor(context, [[UIColor clearColor] CGColor]);
    CGContextFillRect(context, CGRectMake(0, 0, outputSize.width, outputSize.height));
    
    CGAffineTransform uiCoords = CGAffineTransformMakeScale(outputSize.width / cropSize.width, outputSize.height / cropSize.height);
    uiCoords = CGAffineTransformTranslate(uiCoords, cropSize.width/2.0, cropSize.height / 2.0);
    uiCoords = CGAffineTransformScale(uiCoords, 1.0, -1.0);
    CGContextConcatCTM(context, uiCoords);
    
    CGContextConcatCTM(context, transform);
    CGContextScaleCTM(context, 1.0, -1.0);
    
    CGContextDrawImage(context, CGRectMake(-imageViewSize.width/2, -imageViewSize.height/2.0, imageViewSize.width, imageViewSize.height), source);
    CGImageRef resultRef = CGBitmapContextCreateImage(context);
    CGContextRelease(context);
    CGImageRelease(source);
    return resultRef;
}

+ (CGImageRef)newScaledImage:(CGImageRef)source toSize:(CGSize)size {
    CGSize srcSize = size;
    CGColorSpaceRef rgbColorSpace = CGColorSpaceCreateDeviceRGB();
    CGContextRef context = CGBitmapContextCreate(NULL, size.width, size.height, 8, 0, rgbColorSpace, kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big);
    CGColorSpaceRelease(rgbColorSpace);
    
    CGContextSetInterpolationQuality(context, kCGInterpolationNone);
    CGContextTranslateCTM(context, size.width/2, size.height/2);
    
    CGContextDrawImage(context, CGRectMake(-srcSize.width/2, -srcSize.height/2, srcSize.width, srcSize.height), source);
    
    CGImageRef resultRef = CGBitmapContextCreateImage(context);
    CGContextRelease(context);
    return resultRef;
}

/// 获取圆形图片
+ (UIImage *)circularClipImage:(UIImage *)image {
    UIGraphicsBeginImageContextWithOptions(image.size, NO, [UIScreen mainScreen].scale);
    
    CGContextRef ctx = UIGraphicsGetCurrentContext();
    CGRect rect = CGRectMake(0, 0, image.size.width, image.size.height);
    CGContextAddEllipseInRect(ctx, rect);
    CGContextClip(ctx);
    
    [image drawInRect:rect];
    UIImage *circleImage = UIGraphicsGetImageFromCurrentImageContext();
    
    UIGraphicsEndImageContext();
    return circleImage;
}

@end


@implementation UIImage (TZGif)

+ (UIImage *)sd_tz_animatedGIFWithData:(NSData *)data {
    if (!data) {
        return nil;
    }
    
    CGImageSourceRef source = CGImageSourceCreateWithData((__bridge CFDataRef)data, NULL);
    
    size_t count = CGImageSourceGetCount(source);
    
    UIImage *animatedImage;
    
    if (count <= 1) {
        animatedImage = [[UIImage alloc] initWithData:data];
    }
    else {
        // images数组过大时内存会飙升，在这里限制下最大count
        NSInteger maxCount = [TZImagePickerConfig sharedInstance].gifPreviewMaxImagesCount ?: 50;
        NSInteger interval = MAX((count + maxCount / 2) / maxCount, 1);
        
        NSMutableArray *images = [NSMutableArray array];
        
        NSTimeInterval duration = 0.0f;
        
        for (size_t i = 0; i < count; i+=interval) {
            CGImageRef image = CGImageSourceCreateImageAtIndex(source, i, NULL);
            if (!image) {
                continue;
            }
            
            duration += [self sd_frameDurationAtIndex:i source:source] * MIN(interval, 3);
            
            [images addObject:[UIImage imageWithCGImage:image scale:[UIScreen mainScreen].scale orientation:UIImageOrientationUp]];
            
            CGImageRelease(image);
        }
        
        if (!duration) {
            duration = (1.0f / 10.0f) * count;
        }
        
        animatedImage = [UIImage animatedImageWithImages:images duration:duration];
    }
    
    CFRelease(source);
    
    return animatedImage;
}

+ (float)sd_frameDurationAtIndex:(NSUInteger)index source:(CGImageSourceRef)source {
    float frameDuration = 0.1f;
    CFDictionaryRef cfFrameProperties = CGImageSourceCopyPropertiesAtIndex(source, index, nil);
    NSDictionary *frameProperties = (__bridge NSDictionary *)cfFrameProperties;
    NSDictionary *gifProperties = frameProperties[(NSString *)kCGImagePropertyGIFDictionary];
    
    NSNumber *delayTimeUnclampedProp = gifProperties[(NSString *)kCGImagePropertyGIFUnclampedDelayTime];
    if (delayTimeUnclampedProp) {
        frameDuration = [delayTimeUnclampedProp floatValue];
    }
    else {
        
        NSNumber *delayTimeProp = gifProperties[(NSString *)kCGImagePropertyGIFDelayTime];
        if (delayTimeProp) {
            frameDuration = [delayTimeProp floatValue];
        }
    }
    
    // Many annoying ads specify a 0 duration to make an image flash as quickly as possible.
    // We follow Firefox's behavior and use a duration of 100 ms for any frames that specify
    // a duration of <= 10 ms. See <rdar://problem/7689300> and <http://webkit.org/b/36082>
    // for more information.
    
    if (frameDuration < 0.011f) {
        frameDuration = 0.100f;
    }
    
    CFRelease(cfFrameProperties);
    return frameDuration;
}

@end