CBLImageManipulationHelpers

Objective-C


@interface CBLImageManipulationHelpers : NSObject

Swift

class ImageManipulationHelpers : NSObject

Helper class for working with image data.


                      
                      
                      +imageDataByRotatingImageData:forRotation:

Rotates an image to orient it based on the given EXIF rotation value.

Declaration

Objective-C

+ (nullable NSData *)imageDataByRotatingImageData:(nonnull NSData *)sourceData
                                      forRotation:(CBLExifRotation)rotation;

Swift

class func imageData(byRotatingImageData sourceData: Data, for rotation: ExifRotation) -> Data?

Parameters

`sourceData`	The source image data.
`rotation`	The EXIF rotation to apply to the image data.

Return Value

The rotated image, or nil if the given data wasn’t a valid image or an error occurred.


                      
                      
                      +cropMetadatalessThumbnail:basedOnMetadata:

Crop the given thumbnail image based on the given metadata.

Embedded thumbnails tend to be of a fixed size no matter the size and aspect ratio of the original image. This can result in black bars being encoded into the thumbnail image. This image will attempt to derive and perform a sensible crop based on the passed ImageIO metadata.

Declaration

Objective-C

+ (UIImage *_Nonnull)cropMetadatalessThumbnail:(nonnull CGImageRef)thumbnail
                               basedOnMetadata:
                                   (nullable NSDictionary *)metadata;

Swift

class func cropMetadatalessThumbnail(_ thumbnail: CGImage, basedOnMetadata metadata: [AnyHashable : Any]?) -> UIImage

Parameters

`thumbnail`	The thumbnail image to crop.
`metadata`	The metadata to derive the crop factor from.

Return Value

The cropped image.


                      
                      
                      +cropMetadatalessThumbnail:toPreRotationRatio:

Crop the given thumbnail image to the given aspect ratio.

Declaration

Objective-C

+ (UIImage *_Nonnull)cropMetadatalessThumbnail:(nonnull CGImageRef)image
                            toPreRotationRatio:(CGFloat)ratio;

Swift

class func cropMetadatalessThumbnail(_ image: CGImage, toPreRotationRatio ratio: CGFloat) -> UIImage

Parameters

`image`	The image to crop.
`ratio`	The aspect ratio to crop to.

Return Value

The cropped image.