Why does my app show a box with question mark on mmssheet? - ios

Question

I am creating an app that makes use of iMessage and MMS.
[stillImageOutput captureStillImageAsynchronouslyFromConnection:videoConnection completionHandler:^(CMSampleBufferRef imageDataSampleBuffer, NSError *error) {
if (imageDataSampleBuffer) {
The problem is, after I take a picture then click the send button, the image randomly becomes a question mark.
NSData *imageData = [AVCaptureStillImageOutput jpegStillImageNSDataRepresentation:imageDataSampleBuffer];
The above code was the first the one we used followed by:
[self sendSMSmessage:myMessage image:imageData];
next, in the sendSMSmessage method, the following codes were called:
MFMessageComposeViewController *myText = [[MFMessageComposeViewController alloc] init];
[myText setMessageComposeDelegate:self];
[myText setBody:myMessage];
[myText addAttachmentData:image typeIdentifier:#"image/jpeg" filename:#"image.jpeg"];
Then, I present the MFMessageComposeViewController myText
[self presentViewController:myText animated:YES completion:nil];
Then, I clicked Send... It successfully sent for the app and I can see the picture on MFMessageComposeViewController. But when I try to look at iMessage, some of the pictures I tried to send is good. But some are not. Some show question mark. Did the images got corrupted in the process or what? I tried to compress the image using the following:
CGFloat compressionQuality = 0.3;
NSData *imageData = [NSData dataWithData:(UIImageJPEGRepresentation
([UIImage imageWithData:[AVCaptureStillImageOutput jpegStillImageNSDataRepresentation:imageDataSampleBuffer]]
, compressionQuality))];
but still performs the same. In 10 tries, I get something like 4 failed images. Could it be a problem in iPhone or just my app itself? Thanks!

Answer 1

I don't know if some people would experience this, but the thing I did to fix this was:
Declaring the imageData as a strong reference:
__strong NSData *imageData = [AVCaptureStillImageOutput jpegStillImageNSDataRepresentation:imageDataSampleBuffer];
And then I changed the typeIdentifier of the myText composer into #"public.jpeg" instead of #"image/jpeg"
[myText addAttachmentData:image typeIdentifier:#"public.jpeg" filename:#"image.jpeg"];