iOS根据屏幕的宽高等比压缩图片

/**
*  上传原图
*
*  @param image 传过来的图片
*
*  @return 返回的图片
*/
- (UIImage*)imageCompressWithSimple:(UIImage*)image{
CGSize size = image.size;
CGFloat scale = 1.0;
//TODO:KScreenWidth屏幕宽
if (size.width > KScreenWidth || size.height > KScreenHeight) {
if (size.width > size.height) {
scale = KScreenWidth / size.width;
}else {
scale = KScreenHeight / size.height;
}
}
CGFloat width = size.width;
CGFloat height = size.height;
CGFloat scaledWidth = width * scale;
CGFloat scaledHeight = height * scale;
CGSize secSize =CGSizeMake(scaledWidth, scaledHeight);
//TODO:设置新图片的宽高
UIGraphicsBeginImageContext(secSize); // this will crop
[image drawInRect:CGRectMake(0,0,scaledWidth,scaledHeight)];
UIImage* newImage= UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return newImage;
}