[Bug]: pict-rs transformations don't apply to proxied images

[Xyphyn]

Requirements

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Summary

I'm unsure if this is a pict-rs issue or a Lemmy issue, but looking at pict-rs's API, I think it's more likely to be Lemmy.

Many clients use pict-rs image transformations to load images more efficiently, such as thumbnail and format. Recently, as I was testing performance of my app, I noticed images were taking a ridiculous amount of bandwidth. Looking into it, images via /image_proxy were being loaded at their full size, regardless of these arguments.

This is not good for bandwidth, as this 24px avatar is being loaded in 4K.

These arguments still work fine for non proxied images, and before 0.19.4.

Steps to Reproduce

1. Fetch an image via /image_proxy
2. Add arguments to control image size/format, such as ?thumbnail=256&format=webp
3. Observe how the received image ignores those arguments.

Technical Details

The solution to this is likely to pass these parameters to pict-rs.

Version

0.19.5

Lemmy Instance URL

lemm.ee

[dessalines]

Could you link the post / profile example? I'm pretty sure pictrs supports this and might just be an issue with lemmy-ui.

[Xyphyn]

Here's one image:

https://lemm.ee/api/v3/image_proxy?url=https%3A%2F%2Fmander.xyz%2Fpictrs%2Fimage%2Fdbeda0de-d3fb-4fab-8703-3e52e72cb4db.jpeg&format=webp&thumbnail=48

Notice how format is set to webp and thumbnail is 48, but it still loads the full image. Lemmy-ui doesn't use these afaik (if recommend it should!), so this issue doesn't completely apply there.

Every proxied image has this issue.

[dessalines]

@asonix is there a way to do image processing on these proxied image urls?

[Nutomic]

It seems like we need to request proxied images via /image/process if there are any parameters. Basically the same logic as here.

[dessalines]

K, I'll get this.