我使用UIImagePickerController在我的iOS应用程序中选择图像，我知道可以通过info[UIImagePickerControllerMediaMetadata]获取exif信息。但是当我通过UIImage将我的图像上传到我的服务器时，大多数exif信息都是条纹的。我想知道是否可以在Http请求中将exif信息添加到我的图像中（之后上传为jpg的图像）。如果没有，我该如何解决这个问题？我想改变Make，Model属性（换句话说，用什么设备来拍这张照片）
以下是我的代码片段：
func Tapped() {
let myPickerController = UIImagePickerController()
myPickerController.delegate = self
myPickerController.sourceType = UIImagePickerControllerSourceType.Camera
myPickerController.allowsEditing = false
self.presentViewController(myPickerController, animated: true, completion: nil)
}
func imagePickerController(picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : AnyObject]) {
let image = info[UIImagePickerControllerOriginalImage] as? UIImage
myImageView.image = image
UIImageWriteToSavedPhotosAlbum(image!, self, #selector(ViewController.image(_:didFinishSavingWithError:contextInfo:)), nil)
self.dismissViewControllerAnimated(true, completion: nil)
}
func myImageUploadRequest()
{
let myUrl = NSURL(string: "http://XXXXXX/Uploadfile")
let request = NSMutableURLRequest(URL:myUrl!)
request.HTTPMethod = "POST"
let param = [
"userId" : "7"
]
let boundary = generateBoundaryString()
request.setValue("multipart/form-data; boundary=\(boundary)", forHTTPHeaderField: "Content-Type")
let imageData = UIImageJPEGRepresentation(myImageView.image!, 1)
if(imageData == nil) { return; }
request.HTTPBody = createBodyWithParameters(param, filePathKey: "file", imageDataKey: imageData!, boundary: boundary)
myActivityIndicator.startAnimating()
let task = NSURLSession.sharedSession().dataTaskWithRequest(request) {
data, response, error in
if error != nil {
print("error=\(error)")
return
}
// You can print out response object
print("******* response = \(response)")
// Print out response body
let responseString = NSString(data: data!, encoding: NSUTF8StringEncoding)
print("****** response data = \(responseString!)")
do{
let json = try NSJSONSerialization.JSONObjectWithData(data!, options: .MutableContainers) as? NSDictionary
}catch{
print(error)
}
dispatch_async(dispatch_get_main_queue(),{
self.myActivityIndicator.stopAnimating()
self.myImageView.image = nil
})
}
task.resume()
}
func createBodyWithParameters(parameters: [String: String]?, filePathKey: String?, imageDataKey: NSData, boundary: String) -> NSData {
let body = NSMutableData();
if parameters != nil {
for (key, value) in parameters! {
body.appendString("--\(boundary)\r\n")
body.appendString("Content-Disposition: form-data; name=\"\(key)\"\r\n\r\n")
body.appendString("\(value)\r\n")
}
}
let filename = "test.jpg"
let mimetype = "image/jpg"
body.appendString("--\(boundary)\r\n")
body.appendString("Content-Disposition: form-data; name=\"\(filePathKey!)\"; filename=\"\(filename)\"\r\n")
body.appendString("Content-Type: \(mimetype)\r\n\r\n")
body.appendData(imageDataKey)
body.appendString("\r\n")
body.appendString("--\(boundary)--\r\n")
return body
}
func generateBoundaryString() -> String {
return "Boundary-\(NSUUID().UUIDString)"
}
extension NSMutableData {
func appendString(string: String) {
let data = string.dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: true)
appendData(data!)
}
}
是!最后我做了一个修改EXIF信息的技巧。首先，你可以通过UIImageJPEGRepresentation从信息[UIImagePickerControllerMediaMetadata]和没有EXIF的NSData获取EXIF信息。然后，您可以使用修改的EXIF信息创建新的NSDictionary。之后，在下面调用我的函数，你可以用修改后的EXIF获取图像NSData！
func saveImageWithImageData(data: NSData, properties: NSDictionary, completion: (data: NSData, path: NSURL) -> Void) {
let imageRef: CGImageSourceRef = CGImageSourceCreateWithData((data as CFDataRef), nil)!
let uti: CFString = CGImageSourceGetType(imageRef)!
let dataWithEXIF: NSMutableData = NSMutableData(data: data)
let destination: CGImageDestinationRef = CGImageDestinationCreateWithData((dataWithEXIF as CFMutableDataRef), uti, 1, nil)!
CGImageDestinationAddImageFromSource(destination, imageRef, 0, (properties as CFDictionaryRef))
CGImageDestinationFinalize(destination)
var paths: [AnyObject] = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true)
let savePath: String = paths[0].stringByAppendingPathComponent("exif.jpg")
let manager: NSFileManager = NSFileManager.defaultManager()
manager.createFileAtPath(savePath, contents: dataWithEXIF, attributes: nil)
completion(data: dataWithEXIF,path: NSURL(string: savePath)!)
print("image with EXIF info converting to NSData: Done! Ready to upload! ")
}
使用和mergind来自其他帖子的一些信息，我在Swift中使用Dictionary来解决问题。我在AVCapturePhoto的AVFounfation回调的captureOutput中使用它：
func photoOutput(_ output: AVCapturePhotoOutput,
didFinishProcessingPhoto photo: AVCapturePhoto,
error: Error?) {
//retrieve exif information
var photoFormatDescription: CMFormatDescription?
CMVideoFormatDescriptionCreateForImageBuffer(kCFAllocatorDefault, photoPixelBuffer, &photoFormatDescription)
var metadataAttachments: Dictionary = photo.metadata as Dictionary
if var exifData = metadataAttachments["{Exif}"] as? [String: Any] {
exifData[kCGImagePropertyExifUserComment as String] = "<whatever you want to write>"
metadataAttachments[kCGImagePropertyExifDictionary as String] = exifData
}
}
之后“metadataAttachments”用于构建最终图像（在我的例子中使用CGImageDestinationAddImage）
它似乎工作（尝试在使用Swift 4.0的项目构建中）
希望它可以帮助！
SWIFT 3
如果您正在捕获视频并获取CMSampleBuffer，则可以使用更新EXIF元数据的方法。在iOS9的情况下，我没有得到DateTimeOriginal，虽然在iOS10中DataTimeOriginal已经存在。因此我不得不添加几个额外的键值。
self.stillCameraOutput.captureStillImageAsynchronously(from: connectionVideo) { (sampleBuffer, err) in
if let err = err {
blockCompletion(nil, err as NSError?)
}
else {
if let sampleBuffer = sampleBuffer {
let rawMetadata = CMCopyDictionaryOfAttachments(nil, sampleBuffer, CMAttachmentMode(kCMAttachmentMode_ShouldPropagate))
let metadata = CFDictionaryCreateMutableCopy(nil, 0, rawMetadata) as NSMutableDictionary
let exifData = metadata.value(forKey: "{Exif}") as? NSMutableDictionary
print("EXIF DATA: \(exifData)")
if let dateTime = exifData?["DateTimeOriginal"] as? String {
print("DateTime exists \(dateTime)")
}
else {
exifData?.setValue(Date().exifDate(), forKey: "DateTimeOriginal")
}
if let dateTime = exifData?["DateTimeDigitized"] as? String {
print("DateTime exists \(dateTime)")
}
else {
exifData?.setValue(Date().exifDate(), forKey: "DateTimeDigitized")
}
metadata.setValue(exifData, forKey: "{Exif}")
CMSetAttachments(sampleBuffer, metadata as CFDictionary, CMAttachmentMode(kCMAttachmentMode_ShouldPropagate))
let rawMetadata2 = CMCopyDictionaryOfAttachments(nil, sampleBuffer, CMAttachmentMode(kCMAttachmentMode_ShouldPropagate))
let metadata2 = CFDictionaryCreateMutableCopy(nil, 0, rawMetadata2) as NSMutableDictionary
let exifData2 = metadata2.value(forKey: "{Exif}") as? NSMutableDictionary
print("EXIF DATA: \(exifData2)")
if let dataImage = AVCaptureStillImageOutput.jpegStillImageNSDataRepresentation(sampleBuffer) {
blockCompletion(dataImage, nil)
}
else {
blockCompletion(nil, nil)
}
}
else {
blockCompletion(nil, nil)
}
}
}