Creating Thumbnail from Video - Improving Speed Performance - AVAsset - iPhone [duplicate]

Answer 1

This is a generic code, you should just pass a path for the media file and set the ratio between 0 and 1.0.

+ (UIImage*)previewFromFileAtPath:(NSString*)path ratio:(CGFloat)ratio
{
    AVAsset *asset = [AVURLAsset assetWithURL:[NSURL fileURLWithPath:path]];
    AVAssetImageGenerator *imageGenerator = [[AVAssetImageGenerator alloc]initWithAsset:asset];
    CMTime duration = asset.duration;
    CGFloat durationInSeconds = duration.value / duration.timescale;
    CMTime time = CMTimeMakeWithSeconds(durationInSeconds * ratio, (int)duration.value);
    CGImageRef imageRef = [imageGenerator copyCGImageAtTime:time actualTime:NULL error:NULL];
    UIImage *thumbnail = [UIImage imageWithCGImage:imageRef];
    CGImageRelease(imageRef);

    return thumbnail;
}

Answer 2

Swift solution:

func previewImageForLocalVideo(url:NSURL) -> UIImage?
{
    let asset = AVAsset(URL: url)
    let imageGenerator = AVAssetImageGenerator(asset: asset)
    imageGenerator.appliesPreferredTrackTransform = true

    var time = asset.duration
    //If possible - take not the first frame (it could be completely black or white on camara's videos)
    time.value = min(time.value, 2)

    do {
        let imageRef = try imageGenerator.copyCGImageAtTime(time, actualTime: nil)
        return UIImage(CGImage: imageRef)
    }
    catch let error as NSError
    {
        print("Image generation failed with error \(error)")
        return nil
    }
}