UIImage 操作

ps：东西太多了

缩放

- (UIImage *)scaleImage:(UIImage *)image toSize:(CGSize)size {
    
  UIImage *newImg;
    
  UIGraphicsBeginImageContext(size);
  CGRect imageRect = CGRectMake(0, 0, size.width, size.height);
  [image drawInRect:imageRect];
    
  UIImage *newImg = UIGraphicsGetImageFromCurrentImageContext();

  UIGraphicsEndImageContext();
    
  return newImg;
}

截取

- (UIImage *)captureImage:(UIImage *)image toSize:(CGRect)rect {
    
CGImageRef imageRef = CGImageCreateWithImageInRect(image.CGImage, rect);
UIImage *captureImage = [UIImage imageWithCGImage:imageRef];
    
CGImageRelease(imageRef);
    
return captureImage;
}