HEIF images from selfie cam are shown upside down

[leahneukirchen]

Apple phones takes photos in HEIF format, which supports internal rotation.

Find an example attached (gzipped due to GitHub nonsense) with this transform:

transformations:
  angle (ccw): 90
  mirror: vertical

When this picture is sent to a Zulip Flutter client (Android, version 30.0.262), it renders correctly in the preview, but upon clicking it for zoom it shows it upside down. I assume this is because the flag is either ignored or applied twice.

image_43C5969D-384A-40A5-9170-6287B3248972_1754406014.heic.gz

[chrisbobbe]

Hmm, I haven't yet been able to see this image. Here's what happens when I try to open it on my Mac:

Can you please try posting your file in #test here in the Zulip development community and post a link to your message here?

Also helpful:

• What's your Zulip server version, if self-hosting
• Are you uploading the photo through the Zulip app on your Apple phone, the same phone and app version you're seeing the issue on?
• What's your iOS version?

[leahneukirchen]

It seems my EXIF removal was too agressive (hey, Linux can still display it)... I'll upload the original there:

https://chat.zulip.org/#narrow/channel/7-test-here/topic/Test.20case.20for.20zulip-flutter.231785/with/2237637

Clicking on the preview on Zulip Flutter Android flips the image (after 1s or so?). See the thread.

The picture was taken using an iPhone 15.

[chrisbobbe]

Thanks, I've reproduced this and started a chat thread for debugging: #mobile > HEIC image rotation issue #F1785 @ 💬

[gnprice]

Cross-linking the threads: @rajveermalviya filed an issue last week in the Flutter upstream tracker, with a detailed repro:

• HEIC image with vertical flip displays incorrectly via the Image widget (on Android 15 or lower) or outright fails (on Android 16) flutter/flutter#176407

and there's further debugging there.

The bug looks to be ultimately in Android. Hopefully this will lead to an upstream fix there.

We'll then also need to put in place a workaround, since Android updates are slow and a lot of users will have the affected Android versions for a long time to come.

[gnprice]

Further developments on that upstream thread: we're in luck! The folks who work on Flutter's Android embedding decided that the right place for a workaround was in Flutter, and one of them has written a PR to add such a workaround:

• Fix HEIF decoding flutter/flutter#176860

So once that lands, we can upgrade to it and that should resolve this issue. (Both versions of it — the flipped output on Android 15 as originally reported above, and the failure to open the image at all on Android 16 as we discovered in the chat thread in #mobile linked above.)