SDJK_iOS/SDJK/Utils/Category/UIImage/UIImage+RQExtension.m

//
//  UIImage+RQExtension.m
//  RQCommon
//
//  Created by 张嵘 on 2018/11/16.
//  Copyright © 2018 张嵘. All rights reserved.
//

#import "UIImage+RQExtension.h"
#import <AVFoundation/AVFoundation.h>
#import <AssetsLibrary/AssetsLibrary.h>

@implementation UIImage (RQExtension)
/**
 *  根据图片名返回一张能够自由拉伸的图片 (从中间拉伸)
 */
+ (UIImage *)rq_resizableImage:(NSString *)imgName
{
	UIImage *image = [UIImage imageNamed:imgName];
	return [self rq_resizableImage:imgName capInsets:UIEdgeInsetsMake(image.size.height *.5f, image.size.width*.5f, image.size.height*.5f, image.size.width*.5f)];
}

+ (UIImage *)rq_resizableImage:(NSString *)imgName capInsets:(UIEdgeInsets)capInsets
{
	UIImage *image = [UIImage imageNamed:imgName];
	return [image resizableImageWithCapInsets:capInsets];
}

+ (UIImage *)rq_imageAlwaysShowOriginalImageWithImageName:(NSString *)imageName
{
	UIImage *image = [UIImage imageNamed:imageName];
	if ([image respondsToSelector:@selector(imageWithRenderingMode:)])
	{   //iOS 7.0+
		return [image imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];
	}else{
		return image;
	}
}

+ (UIImage*)rq_thumbnailImageForVideo:(NSURL *)videoURL atTime:(NSTimeInterval)time {
	
	AVURLAsset *asset = [[AVURLAsset alloc] initWithURL:videoURL options:nil];
	NSParameterAssert(asset);
	AVAssetImageGenerator *assetImageGenerator =[[AVAssetImageGenerator alloc] initWithAsset:asset];
	assetImageGenerator.appliesPreferredTrackTransform = YES;
	assetImageGenerator.apertureMode = AVAssetImageGeneratorApertureModeEncodedPixels;
	
	CGImageRef thumbnailImageRef = NULL;
	CFTimeInterval thumbnailImageTime = time;
	NSError *thumbnailImageGenerationError = nil;
	thumbnailImageRef = [assetImageGenerator copyCGImageAtTime:CMTimeMake(thumbnailImageTime, 60)actualTime:NULL error:&thumbnailImageGenerationError];
	
	if(!thumbnailImageRef)
		NSLog(@"thumbnailImageGenerationError %@",thumbnailImageGenerationError);
	
	UIImage*thumbnailImage = thumbnailImageRef ? [[UIImage alloc]initWithCGImage: thumbnailImageRef] : nil;
	
	return thumbnailImage;
}

/// 获取屏幕截图
///
/// @return 屏幕截图图像
+ (UIImage *)rq_screenShot {
	// 1. 获取到窗口
	UIWindow *window = [UIApplication sharedApplication].keyWindow;
	
	// 2. 开始上下文
	UIGraphicsBeginImageContextWithOptions(window.bounds.size, YES, 0);
	
	// 3. 将 window 中的内容绘制输出到当前上下文
	[window drawViewHierarchyInRect:window.bounds afterScreenUpdates:NO];
	
	// 4. 获取图片
	UIImage *screenShot = UIGraphicsGetImageFromCurrentImageContext();
	
	// 5. 关闭上下文
	UIGraphicsEndImageContext();
	
	return screenShot;
}




- (UIImage *)rq_fixOrientation {
	
	// No-op if the orientation is already correct
	if (self.imageOrientation == UIImageOrientationUp) return self;
	
	// We need to calculate the proper transformation to make the image upright.
	// We do it in 2 steps: Rotate if Left/Right/Down, and then flip if Mirrored.
	CGAffineTransform transform = CGAffineTransformIdentity;
	
	switch (self.imageOrientation) {
		case UIImageOrientationDown:
		case UIImageOrientationDownMirrored:
			transform = CGAffineTransformTranslate(transform, self.size.width, self.size.height);
			transform = CGAffineTransformRotate(transform, M_PI);
			break;
			
		case UIImageOrientationLeft:
		case UIImageOrientationLeftMirrored:
			transform = CGAffineTransformTranslate(transform, self.size.width, 0);
			transform = CGAffineTransformRotate(transform, M_PI_2);
			break;
			
		case UIImageOrientationRight:
		case UIImageOrientationRightMirrored:
			transform = CGAffineTransformTranslate(transform, 0, self.size.height);
			transform = CGAffineTransformRotate(transform, -M_PI_2);
			break;
		case UIImageOrientationUp:
		case UIImageOrientationUpMirrored:
			break;
	}
	
	switch (self.imageOrientation) {
		case UIImageOrientationUpMirrored:
		case UIImageOrientationDownMirrored:
			transform = CGAffineTransformTranslate(transform, self.size.width, 0);
			transform = CGAffineTransformScale(transform, -1, 1);
			break;
			
		case UIImageOrientationLeftMirrored:
		case UIImageOrientationRightMirrored:
			transform = CGAffineTransformTranslate(transform, self.size.height, 0);
			transform = CGAffineTransformScale(transform, -1, 1);
			break;
		case UIImageOrientationUp:
		case UIImageOrientationDown:
		case UIImageOrientationLeft:
		case UIImageOrientationRight:
			break;
	}
	
	// Now we draw the underlying CGImage into a new context, applying the transform
	// calculated above.
	CGContextRef ctx = CGBitmapContextCreate(NULL, self.size.width, self.size.height,
											 CGImageGetBitsPerComponent(self.CGImage), 0,
											 CGImageGetColorSpace(self.CGImage),
											 CGImageGetBitmapInfo(self.CGImage));
	CGContextConcatCTM(ctx, transform);
	switch (self.imageOrientation) {
		case UIImageOrientationLeft:
		case UIImageOrientationLeftMirrored:
		case UIImageOrientationRight:
		case UIImageOrientationRightMirrored:
			// Grr...
			CGContextDrawImage(ctx, CGRectMake(0,0,self.size.height,self.size.width), self.CGImage);
			break;
			
		default:
			CGContextDrawImage(ctx, CGRectMake(0,0,self.size.width,self.size.height), self.CGImage);
			break;
	}
	
	// And now we just create a new UIImage from the drawing context
	CGImageRef cgimg = CGBitmapContextCreateImage(ctx);
	UIImage *img = [UIImage imageWithCGImage:cgimg];
	CGContextRelease(ctx);
	CGImageRelease(cgimg);
	return img;
}


//将JPEG格式转换为PNG
-(UIImage *)reduceImage:(UIImage *)image percent:(float)percent
{
    NSData *imageData = UIImageJPEGRepresentation(image, percent);
    UIImage *newImage = [UIImage imageWithData:imageData];
    return newImage;
}
//压缩图片尺寸
- (UIImage *)scaledToSize:(CGSize)newSize
{
    //首先要找到缩放比 按长的适配 不足的部分空白
    CGFloat rate =newSize.width*1.0/ self.size.width ;
    if (self.size.height* rate > newSize.height) {
        //过长了。
        rate =newSize.height*1.0/ self.size.height ;
    }
    CGSize size = CGSizeMake(self.size.width*rate, self.size.height*rate);
    
    // Create a graphics image context
    UIGraphicsBeginImageContext(size);
    // new size
    [self drawInRect:CGRectMake(0,0,size.width,size.height)];
    // Get the new image from the context
    UIImage* newImage = UIGraphicsGetImageFromCurrentImageContext();
    
    // End the context
    UIGraphicsEndImageContext();
    // Return the new image.
    return newImage;
}

- (UIImage *)scaledAndCutToSize:(CGSize)newSize{
    
    //首先要找到缩放比 按短的适配 长的部分裁减掉
    CGFloat rate =newSize.width*1.0/ self.size.width ;
    if (self.size.height* rate < newSize.height) {
        //过长了。
        rate =newSize.height*1.0/ self.size.height ;
    }
    CGSize size = CGSizeMake(self.size.width*rate, self.size.height*rate);
    
    UIGraphicsBeginImageContext(size);
    
    [self drawInRect:CGRectMake(0,0,size.width,size.height)];
    // Get the new image from the context
    UIImage* newImage = UIGraphicsGetImageFromCurrentImageContext();
    
    // End the context
    UIGraphicsEndImageContext();
    // Return the new image.
    return newImage;
}

- (UIImage*)imageRotatedByDegrees:(CGFloat)degrees
{
    
    CGFloat width = CGImageGetWidth(self.CGImage);
    CGFloat height = CGImageGetHeight(self.CGImage);
    
    CGSize rotatedSize;
    
    rotatedSize.width = width;
    rotatedSize.height = height;
    
    UIGraphicsBeginImageContext(rotatedSize);
    CGContextRef bitmap = UIGraphicsGetCurrentContext();
    CGContextTranslateCTM(bitmap, rotatedSize.width/2, rotatedSize.height/2);
    CGContextRotateCTM(bitmap, degrees * M_PI / 180);
    CGContextRotateCTM(bitmap, M_PI);
    CGContextScaleCTM(bitmap, -1.0, 1.0);
    CGContextDrawImage(bitmap, CGRectMake(-rotatedSize.width/2, -rotatedSize.height/2, rotatedSize.width, rotatedSize.height), self.CGImage);
    UIImage* newImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return newImage;
}

+ (UIImage *)compressImageWith:(UIImage *)image {
    float imageWidth = image.size.width;
    float imageHeight = image.size.height;
    float width = 640;
    float height = image.size.height/(image.size.width/width);

    float widthScale = imageWidth /width;
    float heightScale = imageHeight /height;

    // 创建一个bitmap的context
    // 并把它设置成为当前正在使用的context
    UIGraphicsBeginImageContext(CGSizeMake(width, height));

    if (widthScale > heightScale) {
        [image drawInRect:CGRectMake(0, 0, imageWidth /heightScale , height)];
    }
    else {
        [image drawInRect:CGRectMake(0, 0, width , imageHeight /widthScale)];
    }

    // 从当前context中创建一个改变大小后的图片
    UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
    // 使当前的context出堆栈
    UIGraphicsEndImageContext();

    return newImage;

}

/**
 获取网络图片高度
 */
+ (CGSize)getImageSizeWithURL:(id)URL
{
    NSURL * url = nil;
    if ([URL isKindOfClass:[NSURL class]]) {
        url = URL;
    }
    if ([URL isKindOfClass:[NSString class]]) {
        url = [NSURL URLWithString:URL];
    }
    if (!URL) {
        return CGSizeZero;
    }
    CGImageSourceRef imageSourceRef = CGImageSourceCreateWithURL((CFURLRef)url, NULL);
    CGFloat width = 0, height = 0;
    
    if (imageSourceRef) {
        
        // 获取图像属性
        CFDictionaryRef imageProperties = CGImageSourceCopyPropertiesAtIndex(imageSourceRef, 0, NULL);
        
        //以下是对手机32位、64位的处理
        if (imageProperties != NULL) {
            
            CFNumberRef widthNumberRef = CFDictionaryGetValue(imageProperties, kCGImagePropertyPixelWidth);
            
#if defined(__LP64__) && __LP64__
            if (widthNumberRef != NULL) {
                CFNumberGetValue(widthNumberRef, kCFNumberFloat64Type, &width);
            }
            
            CFNumberRef heightNumberRef = CFDictionaryGetValue(imageProperties, kCGImagePropertyPixelHeight);
            
            if (heightNumberRef != NULL) {
                CFNumberGetValue(heightNumberRef, kCFNumberFloat64Type, &height);
            }
#else
            if (widthNumberRef != NULL) {
                CFNumberGetValue(widthNumberRef, kCFNumberFloat32Type, &width);
            }
            
            CFNumberRef heightNumberRef = CFDictionaryGetValue(imageProperties, kCGImagePropertyPixelHeight);
            
            if (heightNumberRef != NULL) {
                CFNumberGetValue(heightNumberRef, kCFNumberFloat32Type, &height);
            }
#endif
            /***************** 此处解决返回图片宽高相反问题 *****************/
            // 图像旋转的方向属性
            NSInteger orientation = [(__bridge NSNumber *)CFDictionaryGetValue(imageProperties, kCGImagePropertyOrientation) integerValue];
            CGFloat temp = 0;
            switch (orientation) {  // 如果图像的方向不是正的，则宽高互换
                case UIImageOrientationLeft: // 向左逆时针旋转90度
                case UIImageOrientationRight: // 向右顺时针旋转90度
                case UIImageOrientationLeftMirrored: // 在水平翻转之后向左逆时针旋转90度
                case UIImageOrientationRightMirrored: { // 在水平翻转之后向右顺时针旋转90度
                    temp = width;
                    width = height;
                    height = temp;
                }
                    break;
                default:
                    break;
            }
            /***************** 此处解决返回图片宽高相反问题 *****************/
            
            CFRelease(imageProperties);
        }
        CFRelease(imageSourceRef);
    }

    return CGSizeMake(width, height);
}
@end