Desktop zoom makes images look very blurry

[civility-bot]

Description

In Desktop Riot 1.6.2, images pasted from the clipboard appear very badly blurred due to being zoomed to fit. Initially I thought this was due to the interface being zoomed a couple time with Ctrl+/=+, but it happens even at Ctrl+0.

Steps to reproduce

• copy this image to the clipboard:
• paste it into a room

The result is badly blurred:

I've tried resizing the Riot window to widths from 1/3 of the image with, to 1.5 the image width, and at no point did the image look like the original (which does look OK in the lightbox).

Should images even stretch, if the window width is larger than the image with?

Version information

• Platform: desktop
  Ubuntu 20
  riot-web version: 1.6.2
  olm version: 3.1.3

[t3chguy]

(which does look OK in the lightbox).

This sounds like the client-side thumbnail generating is causing the blurring

[t3chguy]

Does it also happen if you post it to an unencrypted room?

[civility-bot]

Interesting, no. In an unencrypted room, the image scaling is quite alright, not blurry.

[t3chguy]

So there are issues here with the thumbnail being shown too large, larger than the underlying thumbnail thus causing blurring.

[t3chguy]

ah its a bug with the limiter for really wide images :D

[t3chguy]

This is made worse by the max thumbnail size in Synapse being 800x600 so due to the width being sufficient the height limit in riot doesn't get hit.

[532910]

can confirm this issue

[kittykat]

I can't reproduce the issue. Is anyone else still seeing it? Please tag me in your reply if you have and I'll reopen the issue.

Closing for now as there have not been any more reports in 2 years