How to save a TIFF photo from AVFoundations captureStillImageAsynchronouslyFromConnection to a file with EXIF metadata on an iPhone (iOS)?

Question

With this question I only ask for the possibilities I have with Xcode and iOS without external libraries. I am already exploring the possibility of using libtiff

Answer 1

As you've already cracked 1, 3 and 4, it seems the only hurdle you're missing is saving the data and metadata together. Try this (assuming the unprocessed data is in a CMSampleBufferRef called myImageDataSampleBuffer and you've done the heavy lifting of putting the graphical data into a CGImageRef called myImage):

CFDictionaryRef metadata = CMCopyDictionaryOfAttachments(kCFAllocatorDefault,
  myImageDataSampleBuffer,
  kCMAttachmentMode_ShouldPropagate);
NSFileManager* fm = [[NSFileManager alloc] init];
NSURL* pathUrl = [fm URLForDirectory:saveDir
  inDomain:NSUserDomainMask
  appropriateForURL:nil
  create:YES
  error:nil];
NSURL* saveUrl = [pathUrl URLByAppendingPathComponent:@"myfilename.tif"];
CGImageDestinationRef destination = CGImageDestinationCreateWithURL((__bridge CFURLRef)saveUrl,
  (CFStringRef)@"public.tiff", 1, NULL);
CGImageDestinationAddImage(destination, myImage, metadata);
CGImageDestinationFinalize(destination);
CFRelease(destination);