IOS gets and crops images from a camera or album

Today, we have encountered a problem of uploading user portraits. We need to read images from the album or camera. The code is simple. Extract the key parts as follows:

 

/Load user image-(void) Detail {UIActionSheet * sheet; // determine whether the camera is supported if ([UIImagePickerController isSourceTypeAvailable: available]) {sheet = [[UIActionSheet alloc] initWithTitle: @ "select image" delegate: self cancelButtonTitle: nil destructiveButtonTitle: @ "cancel" otherButtonTitles: @ "", @ "select from album", nil];} else {sheet = [[UIActionSheet alloc] initWithTitle: @ "select image" delegate: self cancelButtonTitle: nil destructiveButtonTitle: @ "cancel" otherButtonTitles: @ "select from album ", nil];} sheet. tag= 255; [sheet showInView: self. view] ;}# pragma mark-action sheet delegte-(void) actionSheet :( UIActionSheet *) actionSheet clickedButtonAtIndex :( NSInteger) buttonIndex {if (actionSheet. tag = 255) {NSUInteger sourceType = camera; // determines whether the camera is supported. if ([UIImagePickerController isSourceTypeAvailable: Camera]) {switch (buttonIndex) {case 0: return; case 1: // camera sourceType = UIImagePickerControllerSourceTypeCamera; break; case 2: // album sourceType = break; break ;}} else {if (buttonIndex = 0) {return ;} else {sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum;} // jump to the camera or album page UIImagePickerController * imagePickerController = [[UIImagePickerController alloc] init]; imagePickerController. delegate = self; imagePickerController. allowsEditing = YES; imagePickerController. sourceType = sourceType; [self presentViewController: imagePickerController animated: YES completion: ^ {}] ;}# pragma mark-image picker delegte-(void) imagePickerController :( UIImagePickerController *) picker didFinishPickingMediaWithInfo :( NSDictionary *) info {[picker dismissViewControllerAnimated: YES completion :{}]; UIImage * image = [info UIImagePickerControllerOriginalImage]; userImageView. image = image; NSData * imageData = encrypt (image, COMPRESSED_RATE); UIImage * compressedImage = [UIImage imageWithData: imageData]; [HttpRequestManager uploadImage: compressedImage httpClient: self. httpClient delegate: self];} // load user image-(void) UesrImageClicked {UIActionSheet * sheet; // determine whether cameras are supported if ([UIImagePickerController isSourceTypeAvailable: available]) {sheet = [[UIActionSheet alloc] initWithTitle: @ "select image" delegate: self cancelButtonTitle: nil destructiveButtonTitle: @ "cancel" otherButtonTitles: @ "", @ "select from album", nil];} else {sheet = [[UIActionSheet alloc] initWithTitle: @ "select image" delegate: self cancelButtonTitle: nil destructiveButtonTitle: @ "cancel" otherButtonTitles: @ "select from album", nil];} sheet. tag= 255; [sheet showInView: self. view] ;}# pragma mark-action sheet delegte-(void) actionSheet :( UIActionSheet *) actionSheet clickedButtonAtIndex :( NSInteger) buttonIndex {if (actionSheet. tag = 255) {NSUInteger sourceType = camera; // determines whether the camera is supported. if ([UIImagePickerController isSourceTypeAvailable: Camera]) {switch (buttonIndex) {case 0: return; case 1: // camera sourceType = UIImagePickerControllerSourceTypeCamera; break; case 2: // album sourceType = break; break ;}} else {if (buttonIndex = 0) {return ;} else {sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum;} // jump to the camera or album page UIImagePickerController * imagePickerController = [[UIImagePickerController alloc] init]; imagePickerController. delegate = self; imagePickerController. allowsEditing = YES; imagePickerController. sourceType = sourceType; [self presentViewController: imagePickerController animated: YES completion: ^ {}] ;}# pragma mark-image picker delegte-(void) imagePickerController :( UIImagePickerController *) picker didFinishPickingMediaWithInfo :( NSDictionary *) info {[picker dismissViewControllerAnimated: YES completion :{}]; UIImage * image = [info UIImagePickerControllerOriginalImage]; userImageView. image = image; NSData * imageData = encrypt (image, COMPRESSED_RATE); UIImage * compressedImage = [UIImage imageWithData: imageData]; [HttpRequestManager uploadImage: compressedImage httpClient: self. httpClient delegate: self];}

Create a form, select a camera or album, and use the callback function to process the returned image.

 

However, the returned image is not a square and is displayed in the user's portrait View, resulting in obvious stretching. I have studied various cropping algorithms for a long time and even want to create a view for processing. I suddenly found that

UIImagePickerControllerOriginalImage

So I tracked it and checked it:

UIKIT_EXTERN NSString * const UIImagePickerControllerMediaType; // an NSString (UIKIT_EXTERN image)

UIKIT_EXTERN NSString * const UIImagePickerControllerOriginalImage; // a UIImage

UIKIT_EXTERN NSString * const UIImagePickerControllerEditedImage; // a UIImage

UIKIT_EXTERN NSString * const UIImagePickerControllerCropRect; // an NSValue (CGRect)

UIKIT_EXTERN NSString * const UIImagePickerControllerMediaURL; // an NSURL

UIKIT_EXTERN NSString * const UIImagePickerControllerReferenceURL NS_AVAILABLE_IOS (4_1); // an NSURL that references

 

It's easy to understand. Use UIImagePickerControllerEditedImage to get everything done.