如何在Swift中将Exif数据写入图像

Question

我试图将EXIF数据写入图像,但CGImageDestinationFinalize崩溃:

var image = info[UIImagePickerControllerOriginalImage] as! UIImage
    let jpeg = UIImageJPEGRepresentation(image, 1.0)
    var source: CGImageSource? = nil
    source = CGImageSourceCreateWithData((jpeg as CFData?)!, nil)
    let metadata = CGImageSourceCopyPropertiesAtIndex(source!, 0, nil) as? [AnyHashable: Any]
    var metadataAsMutable = metadata
    var EXIFDictionary = (metadataAsMutable?[(kCGImagePropertyExifDictionary as String)]) as? [AnyHashable: Any]
    var GPSDictionary = (metadataAsMutable?[(kCGImagePropertyGPSDictionary as String)]) as? [AnyHashable: Any]

    GPSDictionary![(kCGImagePropertyGPSLatitude as String)] = 30.21313
    GPSDictionary![(kCGImagePropertyGPSLongitude as String)] = 76.22346
    EXIFDictionary![(kCGImagePropertyExifUserComment as String)] = "Hello Image"


let UTI: CFString = CGImageSourceGetType(source!)!
    let dest_data = NSMutableData()
    let destination: CGImageDestination = CGImageDestinationCreateWithData(dest_data as CFMutableData, UTI, 1, nil)!
    CGImageDestinationAddImageFromSource(destination, source!, 0, (metadataAsMutable as CFDictionary?))
    CGImageDestinationFinalize(destination)

Answer 1

请检查以下答案.由于EXIFDictionary和GPSDictionary上的零值,您收到错误

 var image = info[UIImagePickerControllerOriginalImage] as! UIImage
 let jpeg = UIImageJPEGRepresentation(image, 1.0)
 var source: CGImageSource? = nil
 source = CGImageSourceCreateWithData((jpeg as CFData?)!, nil)
 let metadata = CGImageSourceCopyPropertiesAtIndex(source!, 0, nil) as? [AnyHashable: Any]
 var metadataAsMutable = metadata
 var EXIFDictionary = (metadataAsMutable?[(kCGImagePropertyExifDictionary as String)]) as? [AnyHashable: Any]
 var GPSDictionary = (metadataAsMutable?[(kCGImagePropertyGPSDictionary as String)]) as? [AnyHashable: Any]

 if !(EXIFDictionary != nil) {
       EXIFDictionary = [AnyHashable: Any]()
    }
  if !(GPSDictionary != nil) {
       GPSDictionary = [AnyHashable: Any]()
   }

   GPSDictionary![(kCGImagePropertyGPSLatitude as String)] = 30.21313
   GPSDictionary![(kCGImagePropertyGPSLongitude as String)] = 76.22346
   EXIFDictionary![(kCGImagePropertyExifUserComment as String)] = "Hello Image"

   let UTI: CFString = CGImageSourceGetType(source!)!
   let dest_data = NSMutableData()
   let destination: CGImageDestination = CGImageDestinationCreateWithData(dest_data as CFMutableData, UTI, 1, nil)!
   CGImageDestinationAddImageFromSource(destination, source!, 0, (metadataAsMutable as CFDictionary?))
            CGImageDestinationFinalize(destination)