Information about a rectangular region detected in a still or video image.
- iOS 8.0+
- macOS 10.10+
- UIKit for Mac 13.0+Beta
- tvOS 9.0+
- Core Image
A detected rectangle feature is not necessarily rectangular in the plane of the image; rather, the feature identifies a shape that may be rectangular in space but which appears in perspective in the image—for example, a paper or book on a desk. The properties of a
CIRectangle object identify its corners in image coordinates.
For example, you can use rectangle feature detection together with the CIPerspectiveCorrection filter to detect rectangular objects in an image or video and transform them to their original orientation.
To detect rectangles in an image or video, choose the
CIDetector type when initializing a
CIDetector object, and use the
CIDetector options to specify the approximate shape of rectangular features to search for. The detector returns at most one rectangle feature, the most prominent found in the image.