How to add overlay to Video?

Sometimes you want to add overlay to the captured video for adding copyright label & watermark image.

You can use AVFoundation framework which provides the ability to edit the captured video. Using this framework, we can edit & add the watermark image & text over the captured video. 

You can use this method by passing the image & video url. You should pass the image which you want to add as a overlay  to the captured video. This method will export the new video with watermark image over the video.

- (void) createWatermark:(UIImage*)image video:(NSURL*)videoURL

{

if (videoURL == nil)

return;

AVURLAsset* videoAsset = [[AVURLAsset alloc]initWithURL:videoURL options:nil];

AVMutableComposition* mixComposition = [AVMutableComposition composition];

AVMutableCompositionTrack* compositionVideoTrack = [mixComposition addMutableTrackWithMediaType:AVMediaTypeVideo  preferredTrackID:kCMPersistentTrackID_Invalid];

AVAssetTrack* clipVideoTrack = [[videoAsset tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0];

[compositionVideoTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, videoAsset.duration)

  ofTrack:clipVideoTrack

atTime:kCMTimeZero error:nil];

[compositionVideoTrack setPreferredTransform:[[[videoAsset tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0] preferredTransform]];

//  create the layer with the watermark image

CALayer* aLayer = [CALayer layer];

aLayer.contents = (id)image.CGImage;

aLayer.frame = CGRectMake(50, 100, image.size.width, image.size.height);

aLayer.opacity = 0.9;

//sorts the layer in proper order

AVAssetTrack* videoTrack = [[videoAsset tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0];

CGSize videoSize = [videoTrack naturalSize];

CALayer *parentLayer = [CALayer layer];

CALayer *videoLayer = [CALayer layer];

parentLayer.frame = CGRectMake(0, 0, videoSize.width, videoSize.height);

videoLayer.frame = CGRectMake(0, 0, videoSize.width, videoSize.height);

[parentLayer addSublayer:videoLayer];

[parentLayer addSublayer:aLayer];

// create text Layer

CATextLayer* titleLayer = [CATextLayer layer];

titleLayer.backgroundColor = [UIColor clearColor].CGColor;

titleLayer.string = @"Dummy text";

titleLayer.font = CFBridgingRetain(@"Helvetica");

titleLayer.fontSize = 28;

titleLayer.shadowOpacity = 0.5;

titleLayer.alignmentMode = kCAAlignmentCenter;

titleLayer.frame = CGRectMake(0, 50, videoSize.width, videoSize.height / 6);

[parentLayer addSublayer:titleLayer];

//create the composition and add the instructions to insert the layer:

AVMutableVideoComposition* videoComp = [AVMutableVideoComposition videoComposition];

videoComp.renderSize = videoSize;

videoComp.frameDuration = CMTimeMake(1, 30);

videoComp.animationTool = [AVVideoCompositionCoreAnimationTool videoCompositionCoreAnimationToolWithPostProcessingAsVideoLayer:videoLayer inLayer:parentLayer];

/// instruction

AVMutableVideoCompositionInstruction* instruction = [AVMutableVideoCompositionInstruction videoCompositionInstruction];

instruction.timeRange = CMTimeRangeMake(kCMTimeZero, [mixComposition duration]);

AVAssetTrack* mixVideoTrack = [[mixComposition tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0];

AVMutableVideoCompositionLayerInstruction* layerInstruction = [AVMutableVideoCompositionLayerInstruction videoCompositionLayerInstructionWithAssetTrack:mixVideoTrack];

instruction.layerInstructions = [NSArray arrayWithObject:layerInstruction];

videoComp.instructions = [NSArray arrayWithObject: instruction];

// export video

_assetExport = [[AVAssetExportSession alloc] initWithAsset:mixComposition presetName:AVAssetExportPresetMediumQuality];

_assetExport.videoComposition = videoComp;

NSLog (@"created exporter. supportedFileTypes: %@", _assetExport.supportedFileTypes);

NSString* videoName = @"NewWatermarkedVideo.mov";

NSString* exportPath = [NSTemporaryDirectory() stringByAppendingPathComponent:videoName];

NSURL* exportUrl = [NSURL fileURLWithPath:exportPath];

if ([[NSFileManager defaultManager] fileExistsAtPath:exportPath])

[[NSFileManager defaultManager] removeItemAtPath:exportPath error:nil];

_assetExport.outputFileType = AVFileTypeQuickTimeMovie;

_assetExport.outputURL = exportUrl;

_assetExport.shouldOptimizeForNetworkUse = YES;

[_assetExport exportAsynchronouslyWithCompletionHandler:

^(void ) {

 

//Final code

 

switch (_assetExport.status)

{

case AVAssetExportSessionStatusUnknown:

NSLog(@"Unknown");

break;

case AVAssetExportSessionStatusWaiting:

NSLog(@"Waiting");

break;

case AVAssetExportSessionStatusExporting:

NSLog(@"Exporting");

break;

case AVAssetExportSessionStatusCompleted:

NSLog(@"Created new water mark image");

_playButton.hidden = NO;

break;

case AVAssetExportSessionStatusFailed:

NSLog(@"Failed- %@", _assetExport.error);

break;

case AVAssetExportSessionStatusCancelled:

NSLog(@"Cancelled");

break;

}

}

];   

}

You can download the sample app from github.