Convert any video url into .mp4 extension without using Avasset - objective-c

Question

My code changes the particular url into .mp4 extension but after conversion it gives the path not specific url with .mp4 extension
VideoURL = [NSURL URLWithString:#"https://www.youtube.com/watch?v=9uLiwb9q0nc"];
AVURLAsset *avAsset = [AVURLAsset URLAssetWithURL:VideoURL options:nil];
NSArray *compatiblePresets = [AVAssetExportSession exportPresetsCompatibleWithAsset:avAsset];
if ([compatiblePresets containsObject:AVAssetExportPresetLowQuality])
{
AVAssetExportSession *exportSession = [[AVAssetExportSession alloc]initWithAsset:avAsset presetName:AVAssetExportPresetLowQuality];
NSString* documentsDirectory= [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
NSString* myDocumentPath= [documentsDirectory stringByAppendingPathComponent:#"temp.mp4"];
url = [[NSURL alloc] initFileURLWithPath:myDocumentPath];
if ([[NSFileManager defaultManager]fileExistsAtPath:myDocumentPath])
{
[[NSFileManager defaultManager]removeItemAtPath:myDocumentPath error:nil];
}
exportSession.outputURL = url;
exportSession.outputFileType = AVFileTypeMPEG4;
exportSession.shouldOptimizeForNetworkUse = YES;
[exportSession exportAsynchronouslyWithCompletionHandler:^{
switch ([exportSession status])
{
case AVAssetExportSessionStatusFailed:
NSLog(#"Export session failed");
break;
case AVAssetExportSessionStatusCancelled:
NSLog(#"Export canceled");
break;
case AVAssetExportSessionStatusCompleted:
{
NSLog(#"Successful!");
}
break;
default:
break;
}
}];
}
else
{
NSLog(#"Video file not supported!");
}

Answer 1

You need AVMutableComposition to do this. Because Asset can't be transcode to MP4 directly under iOS 5.0.
- (BOOL)encodeVideo:(NSURL *)videoURL
{
AVURLAsset *asset = [[AVURLAsset alloc] initWithURL:videoURL options:nil];
// Create the composition and tracks
AVMutableComposition *composition = [AVMutableComposition composition];
AVMutableCompositionTrack *videoTrack = [composition addMutableTrackWithMediaType:AVMediaTypeVideo preferredTrackID:kCMPersistentTrackID_Invalid];
AVMutableCompositionTrack *audioTrack = [composition addMutableTrackWithMediaType:AVMediaTypeAudio preferredTrackID:kCMPersistentTrackID_Invalid];
NSArray *assetVideoTracks = [asset tracksWithMediaType:AVMediaTypeVideo];
if (assetVideoTracks.count <= 0)
{
NSLog(#"Error reading the transformed video track");
return NO;
}
// Insert the tracks in the composition's tracks
AVAssetTrack *assetVideoTrack = [assetVideoTracks firstObject];
[videoTrack insertTimeRange:assetVideoTrack.timeRange ofTrack:assetVideoTrack atTime:CMTimeMake(0, 1) error:nil];
[videoTrack setPreferredTransform:assetVideoTrack.preferredTransform];
AVAssetTrack *assetAudioTrack = [[asset tracksWithMediaType:AVMediaTypeAudio] objectAtIndex:0];
[audioTrack insertTimeRange:assetAudioTrack.timeRange ofTrack:assetAudioTrack atTime:CMTimeMake(0, 1) error:nil];
// Export to mp4
NSString *mp4Quality = [MGPublic isIOSAbove:#"6.0"] ? AVAssetExportPresetMediumQuality : AVAssetExportPresetPassthrough;
NSString *exportPath = [NSString stringWithFormat:#"%#/%#.mp4",
[NSHomeDirectory() stringByAppendingString:#"/tmp"],
[BSCommon uuidString]];
NSURL *exportUrl = [NSURL fileURLWithPath:exportPath];
AVAssetExportSession *exportSession = [[AVAssetExportSession alloc] initWithAsset:composition presetName:mp4Quality];
exportSession.outputURL = exportUrl;
CMTime start = CMTimeMakeWithSeconds(0.0, 0);
CMTimeRange range = CMTimeRangeMake(start, [asset duration]);
exportSession.timeRange = range;
exportSession.outputFileType = AVFileTypeMPEG4;
[exportSession exportAsynchronouslyWithCompletionHandler:^{
switch ([exportSession status])
{
case AVAssetExportSessionStatusCompleted:
NSLog(#"MP4 Successful!");
break;
case AVAssetExportSessionStatusFailed:
NSLog(#"Export failed: %#", [[exportSession error] localizedDescription]);
break;
case AVAssetExportSessionStatusCancelled:
NSLog(#"Export canceled");
break;
default:
break;
}
}];
return YES;
}