iOS Image Editor

A iOS View Controller for image cropping. An alternative to the UIImagePickerController editor with extended features and flexibility. Drop me a line if your're using this on your apps, I would like to know.

Features

• Full image resolution
• Unlimited pan, zoom and rotation
• Zoom and rotation centered on touch area
• Double tap to reset
• Handles EXIF orientations
• Plug-in your own interface

Usage

HFImageEditorViewController *imageEditor = [[HFImageEditorViewController alloc] initWithNibName:@"DemoImageEditor" bundle:nil];

imageEditor.sourceImage = image;
imageEditor.doneCallback = ^(UIImage *editedImage, BOOL canceled){
    ...
}

Configuration Properties

sourceImage

The full resolution UIImage to crop

previewImage

For images larger than 1024 wide or 1024 height, the image editor will create a preview image before the view is shown. If a preview is already available you can get a faster transition by setting the preview propety. For instance, if the image was fetched using the UIImagePickerController:

UIImage *image =  [info objectForKey:UIImagePickerControllerOriginalImage];
NSURL *assetURL = [info objectForKey:UIImagePickerControllerReferenceURL];

[self.library assetForURL:assetURL resultBlock:^(ALAsset *asset) {
    UIImage *preview = [UIImage imageWithCGImage:[asset aspectRatioThumbnail]];
HFImageEditorViewController *imageEditor = [[HFImageEditorViewController alloc] 
    initWithNibName:@"DemoImageEditor" bundle:nil];
    self.imageEditor.sourceImage = image;
    self.imageEditor.previewImage = preview;        
...
} failureBlock:^(NSError *error) {
    NSLog(@"Failed to get asset from library");
}];

doneCallback

The callback block called when the image editor completes. Returns the cropped image and a BOOL that specifies if completion results from a done or cancel actions.

cropSize

A CGSize specifying the width and height of the crop area in screen coordinates. NOTE: Currently HFImageEditorViewController is expecting cropSize to be set only after its view and the frameView outlet have been set. If you subclass HFImageEditorViewController you can do it in viewDidLoad; if not, you should set it after adding HFImageEditorViewController to the view controller hierarchy.

cropRect

A CGRect specifying the crop area in screen coordinates. Use instead of cropSize if the crop area is not centered. NOTE: Currently HFImageEditorViewController is expecting cropRect to be set only after its view and the frameView outlet have been set. If you subclass HFImageEditorViewController you can do it in viewDidLoad; if not, you should set it after adding HFImageEditorViewController to the view controller hierarchy.

outputWidth

The width of the cropped image. If not defined, the width of the source image is assumed.

minimumScale, maximumScale

The bounds for image scaling. If not defined, image zoom is unlimited.

checkBounds

Set to true to bound the image transform so that you dont' get a black backround on the resulting image.

panEnabled, rotateEnabled, scaleEnabled, tapToResetEnabled

BOOL property to enable/disable specific gestures

Output Properties

cropBoundsInSourceImage

Returns a CGRect representing the current crop rectangle in the source image coordinates. Source image coordinates have the origin at the bottom left of the image. Note that, if rotation has been applyed, then cropBoundsInSourceImage represents the bounding box of the rotated crop rectangle.

Interface

Create your own xib for a custom user interface.

• Set HFImageEditorViewController (or subclass) as the file owner
• Set the frameView outlet. This view must implement the HFImageEditorFrame protocol. It must be transparent in the crop area, the image will show behind. A default implementation ImageEditorFrameView is provided
• Connect interface elements to the available actions: done, reset, resetAnimated and cancel.

The demo app also shows how extended controlls can be implemented: three buttons are used for square, portrait and landscape crop.

Use the subclassing hooks (startTransformHook, endTransformHook) if you need to update the interface during image processing (to diable UI controls, for instance).

License

ios-image-editor is available under the MIT license. See the LICENSE file for more info.