.mp4 video stop/start/freeze, restart/update no solution

AnkiMobile (iPhone/iPad)
1

This post is similar to these threads:

My versions:
iPhone iOS 17.4.1
Anki iOS 24.04

Hi,
Recently Anki on my iPhone has had some trouble playing .mp4 videos that used to play fine. Some .mp4 videos still play fine, others seem to stop and start or lose volume or freeze before finishing. Other cards (including cards with .mp3 files or embedded YouTube videos) work fine. All cards (including those with .mp4 videos) work fine on my Mac (Anki 24.04.1).
Any suggestions? Restarting my phone has not helped.
Thanks,
Nick

2

AnkiMobile relies on iOS for playing videos, so I’m afraid this sounds like an iOS bug that was introduced in an iOS update. If it’s consistently only certain videos, have you tried playing those videos inside iOS, but outside AnkiMobile?

3

I copied one video from my collection.media folder to my Desktop on my mac. Then (after it had uploaded to iCloud), I played it using the Files app on my phone. It seemed to play fine.
Curious, I opened Anki, searched for the card with the video, and previewed it. Here is the initial screenshot after pressing play:

IMG_9255.PNG
IMG_9255.PNG750×1334 77.8 KB

The video did not start, then this screen appeared:
IMG_9256
IMG_9256750×1334 22.4 KB

So, in summary, it seems the video can play in the iOS Files app but within Anki there is a problem. Maybe it is a iOS browser issue with autoplay? See: MP4 files not playing in Safari on Iphones | Cloudron Forum

4

Please use the cog to view the card info for that card, then let me know the card ID. I’ll try to reproduce the problem on a device here.

5

Thank you. The card ID is 1700638737211.

6

Thank you. I have made some changes that may help with this - if you’d like to try a beta build when one becomes available, please let me know.

https://docs.ankimobile.net/beta-testing.html

7

It is recommended that the image size of the video file should not be greater than 640 x 360. It is recommended to use the baseline H.264 profile-coded .mp4. In addition, the bitrate of the iPhone is limited to 1.5Mb, but it is recommended to keep the bitrate below 900kb.