JPEG banner quality is visibly degraded in the store

The 0 A.D. arts team uploaded a banner for the snap today, as a JPEG file (the PNG versions weighs more than 2MB). Since the 0 A.D. snap is currently featured, the banner is displayed on the store’s home page, but the quality of the banner is visibly degraded compared to the original JPEG that was uploaded. Does the store do some post-processing to reduce the size of the banners? If so, can it be made less aggressive, to preserve image quality?

This is the URL of the banner displayed in the store:,q_auto,fl_sanitize,w_1104,h_368/

As a comparison, I’m attaching a JPEG export of the original PNG that I did with gimp, at 90% quality:

The store uses Cloudinary as a CDN. As part of the URL you will see the w_1104 or similar and h_368 or similar that tells cloudinary the size of the hole you’re going to be placing the image. Cloudinary then resizes the image to those dimensions if needed. Your source image is 1920x640 and the URL you shared where it doesn’t look as good is scaled to 1104x368 by Cloudinary. Note also that the website is using correct srcset attributes which specify the “retina” or “2x” sizes for high-dpi screens. In this case it is telling Cloudinary to upscale to 2208x736.

There’s something that’s not working as intended, then.
My screen resolution is 1920×1080, I’m viewing the store in a maximized chromium (the snap, of course) window, and the banner occupies a rectangle of dimensions 1242×414. The aspect ratio is good, but the scaled resolution that’s requested isn’t.

I’ve created an issue on for this. Thanks for the heads up.