旋转和裁剪UIImage

也许这会有所帮助

//init
CIImage *image = [CIImage imageWithCGImage:CGImageRef];
//rotation
CIImage *rotatedImage = [image imageByApplyingTransform:someTransform];
//crop
CIImage *croppedImage = [rotatedImage imageByCroppingToRect:someRect];

对于旋转,您需要应用

 CGAffineTransform transform = CGAffineTransformTranslate(self.imageView.transform,deltaX,deltaY);
 transform = CGAffineTransformRotate(transform, recognizer.rotation);
 transform = CGAffineTransformTranslate(transform, -deltaX, -deltaY);
 self.imageView.transform = transform;

对于裁剪,只需更改imageView的框架

要转换本地坐标的图像,只需使用:

// converts a point in local coordinate space to window coordinates. 
[self.imageView convertPoint:localPosition toView:nil];

// use this method to calculate a view's origin in window space like this:
[self.imageView convertPoint:self.imageView.frame.origin toView:nil];

如果您计划将图像编辑器集成到应用程序中,您可能希望考虑使用第三方,如: https://github.com/heitorfr/ios-image-editor