APNG Animation Playing Too Fast

[alexander-steel]

Hi. I have an issue where the APNG animation plays at an extremely fast speed when I load it with a certain piece of code. Is this a bug?

"The application starts by displaying a splash screen. After the splash screen completes, the main ViewController is loaded. The APNG images are set up within the viewDidLoad method of the main ViewController."

2023-10-26.18.41.34.mov

let apngImage = try! APNGImage(named: defaultImageName)
        imageView.autoStartAnimationWhenSetImage = false
        setImage(image: apngImage)
        imageView.startAnimating()
    }

    private func setImage(image: APNGImage) {
        imageView.image = image
        setFrameSize(image: image)
    }

    private func setFrameSize(image: APNGImage) {
        let deviceWidth = UIScreen.main.bounds.width
        let frameHeight = deviceWidth * image.size.height / image.size.width
        frame.size = CGSize(width: deviceWidth, height: frameHeight)
    }

[onevcat]

@alexander-steel Does the same thing happen in the viewWillAppear:? And if possible, can you give me a link or post the used image here? I can check if it is the issue in the image itself.

[devflow]

Same issue on iOS 17. but 16 works normally.

[onevcat]

Does it happen for all images or a certain one? Any reproducible code snippet or sample images are welcome and helpful for tracking this better.

[devflow]

@onevcat

I've committed a few lines to my repository to reproduce the bug (Master branch) Please check it!, thanks!

https://github.com/devflow/APNGKit

[onevcat]

Umm, seems it is an issue that the first .applicationDidBecomeActive notification comes earlier for the app startup than iOS 16, and an edge case happens if there is already an instance of APNGImage which receives a wrong timestamp.

Fixed in #140

[onevcat]

Fixed and released as 2.2.4.

[devflow]

it seems like still having issue. at my forked repo with apngkit 2.2.4. (iOS 17, Simulator)

[devflow]

it seems like still having issue. at my forked repo with apngkit 2.2.4. (iOS 17, Simulator)

Ok, it's only happening when launch an app with XCode. other normal app launch behavior likes SB or Spotlight works as well. it not important issue.

Thank you.

[onevcat]

A stupid error. I will fix again soon.

[onevcat]

Ref: #141

[onevcat]

@devflow Done in 2.2.5. Do you have a chance to check it again?

[devflow]

@onevcat yes, 2.2.5 works as well!! at both DEMO and the private project. 💯