Add a text layer to video at specific time

Question

I want to add a text layer to a video for the last 4 seconds of the video. This is what i have so far:

// 1 - Set up the watermark text layer
    CATextLayer *waterMarkText = [[CATextLayer alloc] init];
    [waterMarkText setFont:@"Helvetica-Neue"];
    [waterMarkText setFontSize:30];
    [waterMarkText setFrame:CGRectMake(0, 0, self.size.width, 80)];
    [waterMarkText setString:@"made with Videofy"];
    [waterMarkText setAlignmentMode:kCAAlignmentRight];
    [waterMarkText setForegroundColor:[[UIColor whiteColor] CGColor]];

//Fade In the watermark
    CABasicAnimation *fadeInAnimation = [CABasicAnimation animationWithKeyPath:@"opacity"];

    fadeInAnimation.duration = 2;
    fadeInAnimation.fromValue = [NSNumber numberWithFloat:0.0];
    fadeInAnimation.toValue = [NSNumber numberWithFloat:1.0];
    fadeInAnimation.beginTime = videoDuration - 4;
    fadeInAnimation.removedOnCompletion = NO;
    [overlayLayer addAnimation:fadeInAnimation forKey:@"animateOpacity"];

The animation is added to the final video but the watermark is visible from the beginning of the video. How can I set the opacity to 0 before the animation starts?

(I have tried setting the opacity of the watermarkText to 0 but that seems to override the animation. )

Try to set waterMarkText's opacity to 0.0 after creating watermark, and change animation key from "animateOpacity" to "opacity". And try to add animation to waterMarkText, not to overlayLayer. Also, do you even add watermark layer to your root layer? — eoLithic, Nov 09 '14 at 02:47
I am also facing the same issue @Kaitis, please give some suggestions.. — Anand Gautam, Apr 26 '18 at 11:14
You will need to add key times to your animation. See the answer [here](https://stackoverflow.com/questions/50039910/add-text-to-video-for-specific-time-in-ios). — Nare Muradyan, May 17 '20 at 18:00

Nare Muradyan · Answer 1 · 2020-05-19T16:31:16.750

So for the appearing and disappearing to work you will need to add two animations - one for each. Here is a sample code that works for me. In this particular case I add a text layer from 0 to 1 seconds of the video. You should put your own values for the begin times of animations. You should set the opacity to 0 in the beginning.

        textLayer.opacity = 0

        let startVisible = CABasicAnimation(keyPath: "opacity")
        startVisible.duration = 0.1 // for appearing in duration
        startVisible.repeatCount = 1
        startVisible.fromValue = 0.0
        startVisible.toValue = 1.0
        startVisible.beginTime = 0.0 // overlay time range start second
        startVisible.isRemovedOnCompletion = false
        startVisible.fillMode = CAMediaTimingFillMode.forwards
        textLayer.add(startVisible, forKey: "startAnimation")

        let endVisible = CABasicAnimation(keyPath: "opacity")
        endVisible.duration = 0.1 // for disappearing in duration
        endVisible.repeatCount = 1
        endVisible.fromValue = 1.0
        endVisible.toValue = 0.0
        endVisible.beginTime = 1.0 // overlay time range end second
        endVisible.fillMode = CAMediaTimingFillMode.forwards
        endVisible.isRemovedOnCompletion = false
        textLayer.add(endVisible, forKey: "endAnimation")

Add a text layer to video at specific time

1 Answers1