The page lists the assets used in the Ubuntu Desktop image and their format at the time of Kinetic

Those are expected to change every cycle

Wallpapers

• default background image - 4096x2304 png

request to have light and dark variants, https://bugs.launchpad.net/ubuntu/+source/ubuntu-wallpapers/+bug/1992481

• grey variant - 4096x2304 png, example https://bazaar.launchpad.net/~ubuntu-art-pkg/ubuntu-wallpapers/ubuntu/revision/1095#Kudu_Wallpaper_Grey_4096x2304.png

Vcs - https://code.launchpad.net/ubuntu-wallpapers

Installer slides

old installer

• background.png - empty background, 752x376 png

https://git.launchpad.net/ubiquity-slideshow-ubuntu/plain/slideshows/ubuntu/slides/link/background.png

• welcome.png - background with mascot on the right to be used in the slid

https://git.launchpad.net/ubiquity-slideshow-ubuntu/plain/slideshows/ubuntu/slides/screenshots/welcome.png

new installer

• wallpaper with mascot on the right, 960x480 png
• wallpaper without mascot, 960x480 png
• logo, 376x376 png

screenshots on https://github.com/canonical/ubuntu-desktop-installer/issues/1188

ideally @2.0x assets for high-DPI screens

Those are usually not changing

Icons

base-files logos

• /usr/share/pixmaps/ubuntu-logo-text-dark.png - ubuntu logo + label to be used on light background, 260x90 png
• /usr/share/pixmaps/ubuntu-logo-text.png - ubuntu logo + label to be used on dark background, 260x90 png
• /usr/share/pixmaps/ubuntu-logo.svg - ubuntu icon, 32x32 svg

the text ones are used in settings

plymouth

• /usr/share/plymouth/ubuntu-logo.png - used on the system start as the bottom of the screen logo, 248x87 png
• /usr/share/plymouth/themes/spinner/bgrt-fallback.png - fallback logo when there is no bios one

humanity-icon-theme

distributor-logo.svg in 16, 22, 24, 48, 64 variants

Other

design is providing assets on https://design.ubuntu.com/downloads/