如何在目标c中裁剪图像？

用户可以在编辑屏幕上更改默认显示的裁剪框大小。 我试着用下面的代码：

- (UIImage *)imageByCropping:(UIImage *)imageToCrop toRect:(CGRect)rect { CGImageRef imageRef = CGImageCreateWithImageInRect([imageToCrop CGImage], rect); UIImage *cropped = [UIImage imageWithCGImage:imageRef]; CGImageRelease(imageRef); return cropped; } 

但它裁剪固定的面积。 如何裁剪用户select的区域？

Answer 1

获取裁剪图像：

 UIImage *croppedImg = nil; CGRect cropRect = CGRectMake("AS YOu Need"); //set your rect size. croppedImg = [self croppIngimageByImageName:self.imageView.image toRect:cropRect]; 

使用以下代码调用croppIngimageByImageName：toRect：返回UIImage方法（ 具有特定大小的图像 ）

 - (UIImage *)croppIngimageByImageName:(UIImage *)imageToCrop toRect:(CGRect)rect { //CGRect CropRect = CGRectMake(rect.origin.x, rect.origin.y, rect.size.width, rect.size.height+15); CGImageRef imageRef = CGImageCreateWithImageInRect([imageToCrop CGImage], rect); UIImage *cropped = [UIImage imageWithCGImage:imageRef]; CGImageRelease(imageRef); return cropped; } 

Answer 2

  CGRect clippedRect = CGRectMake(0 ,0,180 ,180); CGImageRef imageRef = CGImageCreateWithImageInRect(imgVw1.image.CGImage, clippedRect); UIImage *newImage = [UIImage imageWithCGImage:imageRef]; CGImageRelease(imageRef); imgVw1Cliped.image=newImage; NSLog(@"%d",imgVw1Cliped.image.imageOrientation);