Failed to convert .avi to .mp4 in iOS objective-c - ios

Question

I am using a camera to record video's and save them into my documents folder. The problem I am facing is that the video's I got from the camera are .avi files and have to be converted to .mp4 (or any other allowed format).
I use the code below:
SOURCE: iOS Convert AVI to MP4 Format programatically
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *filePath = [documentsDirectory stringByAppendingPathComponent:#"MyVideo.mp4"];
NSURL *outputURL = [NSURL fileURLWithPath:filePath];
[self convertVideoToLowQuailtyWithInputURL:localUrl outputURL:outputURL handler:^(AVAssetExportSession *exportSession)
{
if (exportSession.status == AVAssetExportSessionStatusCompleted) {
// Video conversation completed
}
}];
- (void)convertVideoToLowQuailtyWithInputURL:(NSURL*)inputURL outputURL:(NSURL*)outputURL handler:(void (^)(AVAssetExportSession*))handler {
[[NSFileManager defaultManager] removeItemAtURL:outputURL error:nil];
AVURLAsset *asset = [AVURLAsset URLAssetWithURL:inputURL options:nil];
AVAssetExportSession *exportSession = [[AVAssetExportSession alloc] initWithAsset:asset presetName:AVAssetExportPresetPassthrough];
exportSession.outputURL = outputURL;
exportSession.outputFileType = AVFileTypeMPEG4;
[exportSession exportAsynchronouslyWithCompletionHandler:^(void) {
handler(exportSession);
}];
}
the exportSession status always fails. But when i try to convert a .mov into a .mp4 is does work.
How come I cannot convert .avi files into .mp4 files ?

Answer 1

Try to print the error message:
switch ([exportSession status]) {
case AVAssetExportSessionStatusFailed:
NSLog(#"Export failed: %#", [[exportSession error] localizedDescription]);
break;
case AVAssetExportSessionStatusCancelled:
NSLog(#"Export canceled");
break;
case AVAssetExportSessionStatusCompleted:
NSLog(#"Successfully");
break;
default:
break;
}
}];
}