iOS等比例缩放图片
//等比例缩小
-(UIImage *)ScalingImage:(UIImage *)image
{
CGRect rect = CGRectMake(0, 0, image.size.width/1.8, image.size.height/1.8);
UIGraphicsBeginImageContext(rect.size);
[image drawInRect:rect];
UIImage *scalingImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return scalingImage;
}
//缩放图片大小
- (UIImage*)scaleWithSize:(CGSize)size {
CGFloat imageWidth = self.size.width;
CGFloat imageHeight = self.size.height;
CGFloat wScale = imageWidth / size.width;
CGFloat hScale = imageHeight / size.height;
NSLog(@"w = %f, h = %f", wScale, hScale);
CGSize newSize = self.size;
BOOL needRedraw;
if (wScale > hScale && wScale > 1) {
newSize.width = size.width;
newSize.height = imageHeight / wScale;
needRedraw = YES;
}
else if (hScale > wScale && hScale > 1) {
newSize.width = imageWidth / hScale;
newSize.height = size.height;
needRedraw = YES;
}
NSLog(@"w = %f, h = %f", newSize.width, newSize.height);
if (needRedraw) {
UIGraphicsBeginImageContext(newSize);
[self drawInRect:CGRectMake(0, 0, newSize.width, newSize.height)];
self = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
}
return self;
}