SIGABRT on cast to UIImage - ios

Question

I'm using FastttCamera as a wrapper to AVFoundation for taking, processing and displaying a picture. Here's my code (a FastttCamera delegate method) in which I cast (FastttCapturedImage *) to (UIImage *):
- (void)cameraController:(FastttCamera *)cameraController didFinishScalingCapturedImage:(FastttCapturedImage *)capturedImage
{
//Use the captured image's data--note that the FastttCapturedImage is cast to a UIImage
NSData *pngData = UIImagePNGRepresentation((UIImage *)capturedImage);
//Save the image, and add the path to this transaction's picPath attribute
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsPath = [paths objectAtIndex:0]; //Get the docs directory
int timestamp = [[NSDate date] timeIntervalSince1970];
NSString *timeTag = [NSString stringWithFormat:#"%d",timestamp];
NSString *filePath = [documentsPath stringByAppendingString:timeTag]; //Add the file name
[pngData writeToFile:filePath atomically:YES]; //Write the file
self.thisTransaction.picPath = filePath;
[self.viewFinder setImage:(UIImage *)capturedImage];
}
However, I'm getting a SIGABRT at the line:
NSData *pngData = UIImagePNGRepresentation((UIImage *)capturedImage);
with this console readout:
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[FastttCapturedImage CGImage]: unrecognized selector sent to instance 0x17e2a100'
I'm confused by the reference to CGImage. Is it a problem with my typecast? There was no complaint on build. Can someone please set me straight?

Answer 1

Read the docs for FastttCapturedImage. It's not a UIImage so you can't just cast it like that. Use the provided property to get the UIImage.
Change the problematic line to:
NSData *pngData = UIImagePNGRepresentation(capturedImage.fullImage);
You have the same problem later:
[self.viewFinder setImage:capturedImage.fullImage];
BTW - you didn't get a problem while compiling because a cast is a way to tell the compiler "trust me, it's really what I'm telling you it is". The problem here is you were wrong, it's not really what you claimed it was. :)