JLChen
2021-11-04 1443556e9ccb1a19ed8e6710c16c8adc4d4f4fb3
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//
//  Copyright © 2020 dahua. All rights reserved.
//
 
#import "UIImage+Compress.h"
 
@implementation UIImage (Compress)
 
- (UIImage *)lc_thumbnailWithImageWithSize:(CGSize)asize {
    UIImage *newimage;
    if (nil == self) {
        newimage = nil;
    }
    else{
        CGSize oldsize = self.size;
        CGRect rect;
        if (asize.width/asize.height > oldsize.width/oldsize.height) {
            rect.size.width = asize.height*oldsize.width/oldsize.height;
            rect.size.height = asize.height;
            rect.origin.x = (asize.width - rect.size.width)/2;
            rect.origin.y = 0;
        }
        else{
            rect.size.width = asize.width;
            rect.size.height = asize.width*oldsize.height/oldsize.width;
            rect.origin.x = 0;
            rect.origin.y = (asize.height - rect.size.height)/2;
        }
        UIGraphicsBeginImageContext(asize);
        CGContextRef context = UIGraphicsGetCurrentContext();
        CGContextSetFillColorWithColor(context, [[UIColor clearColor] CGColor]);
        UIRectFill(CGRectMake(0, 0, asize.width, asize.height));//clear background
        [self drawInRect:rect];
        newimage = UIGraphicsGetImageFromCurrentImageContext();
        UIGraphicsEndImageContext();
    }
    
    return newimage;
}
 
@end