Create a thumbnail or image of an AVPlayer at current time - objective-c

Question

I have implemented an AVPlayer and i want to take an image or thumbnail when clicking on a toolbar button and open in a new UIViewController with UIImageView. The image should be scaled exactly like the AVPlayer.
The segue is already working, i just have to implement that i get the image at the current play time.
Thanks!

Answer 1

Objective-C
AVAsset *asset = [AVAsset assetWithURL:sourceURL];
AVAssetImageGenerator *imageGenerator = [[AVAssetImageGenerator alloc]initWithAsset:asset];
CMTime time = CMTimeMake(1, 1);
CGImageRef imageRef = [imageGenerator copyCGImageAtTime:time actualTime:NULL error:NULL];
UIImage *thumbnail = [UIImage imageWithCGImage:imageRef];
CGImageRelease(imageRef); // CGImageRef won't be released by ARC
Swift
var asset = AVAsset.assetWithURL(sourceURL)
var imageGenerator = AVAssetImageGenerator(asset: asset!)
var time = CMTimeMake(1, 1)
var imageRef = try! imageGenerator!.copyCGImageAtTime(time, actualTime: nil)
var thumbnail = UIImage.imageWithCGImage(imageRef)
CGImageRelease(imageRef) // CGImageRef won't be released by ARC
Swift 3.0
var sourceURL = URL(string: "Your Asset URL")
var asset = AVAsset(url: sourceURL!)
var imageGenerator = AVAssetImageGenerator(asset: asset)
var time = CMTimeMake(1, 1)
var imageRef = try! imageGenerator.copyCGImage(at: time, actualTime: nil)
var thumbnail = UIImage(cgImage:imageRef)
Note : Interpret Swift code according to your swift version.

Answer 2

Try this
- (UIImage*)takeScreeenShot {
AVURLAsset *asset = [[AVURLAsset alloc] initWithURL:vidURL
options:nil];
AVAssetImageGenerator *imageGenerator = [[AVAssetImageGenerator alloc] initWithAsset:asset];
imageGenerator.appliesPreferredTrackTransform = YES;
NSError *err = NULL;
CMTime time = CMTimeMake(1, 60); // time range in which you want
screenshot
CGImageRef imgRef = [imageGenerator copyCGImageAtTime:time actualTime:NULL
error:&err];
return [[UIImage alloc] initWithCGImage:imgRef];
}
Hope this helps !!!

Answer 3

Swift 2.x:
let asset = AVAsset(...)
let imageGenerator = AVAssetImageGenerator(asset: asset)
let screenshotTime = CMTime(seconds: 1, preferredTimescale: 1)
if let imageRef = try? imageGenerator.copyCGImageAtTime(screenshotTime, actualTime: nil) {
let image = UIImage(CGImage: imageRef)
// do something with your image
}

Answer 4

Add below code to generate thumbnail from video.
AVURLAsset *assetURL = [[AVURLAsset alloc] initWithURL:partOneUrl options:nil];
AVAssetImageGenerator *assetGenerator = [[AVAssetImageGenerator alloc] initWithAsset:assetURL];
assetGenerator.appliesPreferredTrackTransform = YES;
NSError *err = NULL;
CMTime time = CMTimeMake(1, 2);
CGImageRef imgRef = [assetGenerator copyCGImageAtTime:time actualTime:NULL error:&err];
UIImage *one = [[UIImage alloc] initWithCGImage:imgRef];

Answer 5

This is how I get a shot of the current visible frame on the scene in Swift:
The key is to
get the current time of the player which is of type CMTime
convert that time into seconds of type Float64
switch the secondss back to CMTime using CMTimeMake. The first parameter which would be where the seconds goes should be cast to Int64
Code:
var myImage: UIImage?
guard let player = player else { return }
let currentTime: CMTime = player.currentTime() // step 1.
let currentTimeInSecs: Float64 = CMTimeGetSeconds(currentTime) // step 2.
let actionTime: CMTime = CMTimeMake(Int64(currentTimeInSecs), 1) // step 3.
let asset = AVAsset(url: fileUrl)
let imageGenerator = AVAssetImageGenerator(asset: asset)
imageGenerator.appliesPreferredTrackTransform = true // prevent image rotation
do{
let imageRef = try imageGenerator.copyCGImage(at: actionTime, actualTime: nil)
myImage = UIImage(cgImage: imageRef)
}catch let err as NSError{
print(err.localizedDescription)
}

Answer 6

Swift extension for generating thumbnails from video
extension AVPlayer {
func generateThumbnail(time: CMTime) -> UIImage? {
guard let asset = currentItem?.asset else { return nil }
let imageGenerator = AVAssetImageGenerator(asset: asset)
do {
let cgImage = try imageGenerator.copyCGImage(at: time, actualTime: nil)
return UIImage(cgImage: cgImage)
} catch {
print(error.localizedDescription)
}
return nil
}
}

Answer 7

When you need to create multiple thumbnails at once the class AVAssetImageGenerator is golden, as it provides an async way.
If you need a Thumbnail-Image of the player's current frame, simply render it's View (platform specific) or its Layer (platform independent):
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
CGSize frameSize = _playerLayer.frame.size;
CGContextRef thumbnailContext = CGBitmapContextCreate(nil, frameSize.width, frameSize.height, 8, 0, colorSpace, kCGBitmapByteOrder32Little | kCGImageAlphaPremultipliedFirst);
CGColorSpaceRelease(colorSpace);
[_playerLayer renderInContext:thumbnailContext];
CGImageRef playerThumbnail = CGBitmapContextCreateImage(thumbnailContext);
CGContextRelease(thumbnailContext);
This is super fast and works synchronously.

Answer 8

Code for 2022:
seconds = .. the normal human-meaning desired time position in the video
guard let pl = .. your player ..
guard let ite = pl.currentItem ..
let testGen = AVAssetImageGenerator(asset: ite.asset)
testGen.maximumSize = CGSize(width: 0, height: .. height of your preview box)
testGen.requestedTimeToleranceBefore = .zero // during development
// or something like ... CMTime(value: .. your tolerance .., timescale: 600)
testGen.requestedTimeToleranceAfter = .zero // during development
// ditto
if #available(tvOS 16, *) {
Task { [weak self] ..
do {
let ct = CMTime(value: CMTimeValue(seconds), timescale: 1)
// NOTE THE "1"
let (foundImage, foundTime) = try await testGen.image(at: ct)
let foundAsSecs = CMTimeGetSeconds(foundTime)
print("tried gen at \(seconds) found as \(foundAsSecs) \n")
self. .. your preview .image = UIImage(cgImage: foundImage)
} catch {
print("gen err \(error)")
}
}
}
Setting the two tolerances is a sophisticated issue, google.
Watch out for the gotchya where timescale of 1 is needed for the CMTime.