iPhone - UIImagePickerController -> save the image to app folder

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Hello!

I have an iPhone application using a UIImagePickerController. As sourceType I have

UIImagePickerControllerSourceTypePhotoLibrary
UIImagePickerControllerSourceTypeCamera
UIImagePickerControllerSourceTypeSavedPhotosAlbum

so the user can make a photo or select one from the photo library from the photos or camera photos.

The image will be displayed in a UIImageView. The image should be saved if the user closes the app. So for text fields, I use NSUserDefaults. I know, it is not a good way to save the image inside the NSUSerDefaults with NSData, so I want to save / copy the image to a folder which is controlled by my application similar to the NSUserDefaults.

How can I do this? I want to save it, and then I can write the path to the file into my NSUserDefaultsand read it on startup of the application.

Thank you in advance & Best Regards.

edited Feb 10 at 15:57

NR4TR
1,9851310

asked Feb 10 at 13:57

Tim
1,3281827

98% accept rate

score 3 · Answer 1 · 2011-02-10 14:12:15Z

You can use the following code in UIImagePickerControllerDelegate delegate implementation

- (void) imagePickerController:(UIImagePickerController *)picker
 didFinishPickingMediaWithInfo:(NSDictionary *)info {

    //obtaining saving path
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentsDirectory = [paths objectAtIndex:0];
    NSString *imagePath = [documentsDirectory stringByAppendingPathComponent:@"latest_photo.png"];

    //extracting image from the picker and saving it
    NSString *mediaType = [info objectForKey:UIImagePickerControllerMediaType];   
    if ([mediaType isEqualToString:@"public.image"]){
        UIImage *editedImage = [info objectForKey:UIImagePickerControllerEditedImage];
        NSData *webData = UIImagePNGRepresentation(editedImage);
        [webData writeToFile:imagePath atomically:YES];
    }
}

That's all

Björn Marschollek 2,2752517 · Answer 2 · 2011-02-10 14:02:21Z

Depending on the file format you want to save, you can use

[UIImagePNGRepresentation(image) writeToFile:path atomically:YES];

or [UIImageJPEGRepresentation(image) writeToFile:path atomically:YES];.

Chris Markle 349116 · Answer 3 · 2011-03-07 05:31:29Z

This is the code to save the UIImage into the document directory. You can use this code in didFinishPickingImage delegate method:

// Create paths to output images
NSString  *pngPath = [NSHomeDirectory();
stringByAppendingPathComponent:@"Documents/Test.png"];
NSString  *jpgPath = [NSHomeDirectory();
stringByAppendingPathComponent:@"Documents/Test.jpg"];

// Write a UIImage to JPEG with minimum compression (best quality)
// The value 'image' must be a UIImage object
// The value '1.0' represents image compression quality as value from 0.0 to 1.0
[UIImageJPEGRepresentation(image, 1.0) writeToFile:jpgPath atomically:YES];

// Write image to PNG
[UIImagePNGRepresentation(image) writeToFile:pngPath atomically:YES];

// Let's check to see if files were successfully written...

// Create file manager
NSError *error;
NSFileManager *fileMgr = [NSFileManager defaultManager];

// Point to Document directory
NSString *documentsDirectory = [NSHomeDirectory();
stringByAppendingPathComponent:@"Documents"];

// Write out the contents of home directory to console
NSLog(@"Documents directory: %@", [fileMgr contentsOfDirectoryAtPath:documentsDirectory error:&error]);

EDIT

You can also use:

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];

to find the path to your application document directory, instead of NSHomeDierctory.

iPhone - UIImagePickerController -> save the image to app folder

3 Answers