Komga: Manually downloaded jxl files are renamed to jpg

Source information

Komga 1.2.39

Steps to reproduce

1. Set up a komga server with jxl files inside cbz
2. Open the komga server in tachiyomi
3. Open some comic/manga
4. Scroll a few pages
5. Exit back to chapter view
6. Download the whole chapter

Expected behavior

The files tachiyomi downloaded should have the same name as in the cbz file.

Actual behavior

The files tachiyomi downloaded (e.g. in /sdcard/Tachiyomi/downloads/Komga (ALL)/[COMIC]/[CHAPTER]/) have jxl extension if they were downloaded by scrolling and jpg extension if they were downloaded manually. The files are still jxl codestream files though.

Tachiyomi version

0.13.1

Android version

Android 11

Other details

Not sure if this is actually an extension problem, but without other sources serving jxl files I’m not sure how to test that.

Acknowledgements

• I have searched the existing issues and this is a new ticket, NOT a duplicate or related to another open issue.
• I have written a short but informative title.
• I have updated the app to version 0.13.1.
• I have updated all installed extensions.
• I have tried the troubleshooting guide.
• If this is an issue with the app itself, I should be opening an issue in the app repository.
• I will fill out all of the requested information in this form.

[Seishirou101]

When downloading, the app uses this function to try and find the extension for the file, so its failing to figure out its a jxl file and defaulting to jpg. However if you read some of the pages, it’ll copy the images from the cache which seems to download it a different way. The pagelist for downloaded chapters is built using this function as one of the tests and its failing to identify jxl as an image format so its returning false therefore excluding it from the pagelist. As far as I’m aware, the online source does not use this to determine the page list. This is more of an app issue so I’m going to close this and open an issue there while referring to this issue.

[TheHardew]

https://files.catbox.moe/jgn56z.cbz

It’s a cbz of 100 images of “rose” from imagemagick. I realised my previous link might have infringed on an IP so I removed my last post so that the link would not be visible in the edit history and I post this link instead.

Still happens on Tachiyomi 0.13.4, Komga extension 1.2.39, Komga “1.153.2”. I actually patched Komga before 1.154.0 released to generate larger thumbnails so it’s not the latest one and it’s not the 1.153.2 release, I do have the jpeg xl support via NightMonkeys though.

So just to be clear:

• open the komga extension from Tachiyomi
• open the cbz, scroll a few pages
• exit the comic viewer
• download the cbz
• go into the download location

The first few pages will have .jxl extension. The rest will have .jpg. Tachiyomi will ignore the files with the proper extension, the number of pages one can read is reduced. The solution is to rename the .jxl files to .jpg or to delete the downloaded chapter and redownload it without opening it first.