Convert UIImage to NSData and save with core data - ios

Question

I have a UIImageView whose image gets set via UIImagePicker
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info{
[picker dismissViewControllerAnimated:YES completion:nil];
self.gImage.image = [info objectForKey:#"UIImagePickerControllerOriginalImage"];
}
I "attempt" to convert this image to NSData and save it with core data:
NSData *imageData = UIImagePNGRepresentation(self.gImage.image);
NSString *savedData = [[NSString alloc]initWithData:imageData encoding:NSUTF8StringEncoding];
//am is a pointer to my entities class. imageData is just a NSString attribute
am.imageData = savedData;
NSError *error;
if (![self.managedObjectContext save:&error]) {
//Handle Error
} else {
[self dismissViewControllerAnimated:YES completion:nil];
}
Then I try to load the image in a separate file:
self.cell.gImage.image = [UIImage imageWithData:[NSData dataWithContentsOfURL:[NSURL URLWithString:self.myEntity.imageData]]];
I cannot see why this is not working. Any help is greatly appreciated!

Answer 1

You can convert a UIImage to NSData like this:
If PNG image
UIImage *image = [UIImage imageNamed:#"imageName.png"];
NSData *imageData = [NSData dataWithData:UIImagePNGRepresentation(image)];
If JPG image
UIImage *image = [UIImage imageNamed:#"imageName.jpg"];
NSData *imageData = UIImageJPEGRepresentation(image, 1.0);
You can store it in CoreData like so (this is one possible useful solution):
[newManagedObject setValue:imageData forKey:#"image"];
You can load the data from CoreData like this:
NSManagedObject *selectedObject = [[self yourFetchCOntroller] objectAtIndexPath:indexPath];
UIImage *image = [UIImage imageWithData:[selectedObject valueForKey:#"image"]];
// Set the image to your image view
yourimageView.image = image;

Answer 2

For swift its just:
UIImage to NSData
imageData = UIImagePNGRepresentation(image)

Answer 3

For storing in database:::
NSInteger RandomIndex = arc4random() % 1000;
NSString *randomImageName =[NSString stringWithFormat:#"Image%i.png",RandomIndex];
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *savedImagePath = [documentsDirectory stringByAppendingPathComponent:randomImageName];
if ([[NSFileManager defaultManager] fileExistsAtPath:savedImagePath]) {
[[NSFileManager defaultManager] removeItemAtPath:savedImagePath error:nil];
NSLog(#"file removed from path");
}
NSLog(#"Saved Image Path : %#",savedImagePath);
NSData* imageData = UIImagePNGRepresentation (image1 );
[imageData writeToFile:savedImagePath atomically:YES];
//am is a pointer to my entities class. imageData is just a NSString attribute
am.imageData = randomImageName;
When you get that image from data base, you can write following code...
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *savedImagePath = [documentsDirectory stringByAppendingPathComponent:randomImageName];
NSData *myData = [NSData dataWithContentsOfFile:savedImagePath];
UIImage *selectedImage = [UIImage imageWithData:myData];
I think it is helpful to you.

Answer 4

On Mac OS you can let Core Data handle this for you by ticking the Transformable box on the attribute in the model, not selecting a specific transformer, and assigning the UIImage directly to the property.
I'm not sure if it works on iOS but it might be worth a try.

Answer 5

To convert an image to NSData try below code...
UIImage *image = [UIImage imageNamed:#"imageName.png"];
NSData *imageData = [NSData dataWithData:UIImagePNGRepresentation(image)];
let me know it is working or not..!!!
Happy Coding!!!!

Answer 6

Try This Code to save image data
to save:
NSManagedObjectContext *context = [self managedObjectContext];
newsObj = [NSEntityDescription insertNewObjectForEntityForName:#"Event" inManagedObjectContext:context];
NSData *imageData = UIImagePNGRepresentation(self.gImage.image);
[newsObj setValue:imageData forKey:#"imgPng"];
NSError *error;
#try{
if (managedObjectContext != nil) {
if (![managedObjectContext save:&error]) {
NSLog(#"Unresolved error %#, %#", error, [error userInfo]);
}
}
}#catch (NSException *exception) {
NSLog(#"inside exception");
}
To Retrive Try this:
NSManagedObjectContext *context = [self managedObjectContext];
NSFetchRequest * fetchRequest = [[NSFetchRequest alloc] init];
NSEntityDescription *entity1 = [NSEntityDescription entityForName:#"Event" inManagedObjectContext:context];
[fetchRequest setEntity:entity1];
NSError *error;
NSArray * array = [self.managedObjectContext executeFetchRequest:fetchRequest error:&error];
if (array == nil) {
NSLog(#"Testing: No results found");
}else {
NSLog(#"Testing: %d Results found.", [array count]);
}
NSData * dataBytes = [[array objectAtIndex:0] imgPng];;
image = [UIImage imageWithData:dataBytes];
[fetchRequest release];
}
#catch (NSException *exception) {
NSLog(#"inside exception");
}

Answer 7

This code save your image data into filedata and you can use it anywhere
-(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingImage:(UIImage *)image1 editingInfo:(NSDictionary *)editingInfo
{
{
CGSize destinationSize = CGSizeMake(170,170);
UIGraphicsBeginImageContext(destinationSize);
[image1 drawInRect:CGRectMake(0,0,destinationSize.width,destinationSize.height)];
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
NsData *filedata = UIImagePNGRepresentation(newImage);
[picker dismissModalViewControllerAnimated:YES];
}
}

Answer 8

Here is what I have done and its working for storing to nsdata.
[productTypeSub setValue:[[NSData alloc] initWithContentsOfURL:[NSURL URLWithString:url]] forKey:#"imgSmall"];
and loading to image with this code
ImgProductType.image= [[UIImage alloc] initWithData:productTypeSub.imgSmall];