# Icon Cache

## Introduction

In order to display icons in software-centers, distributors should offer a repository of cached icons for applications defined in their AppStream XML files. The icons should be PNG files or vectorgraphics (PNG is preferred) and match the name referenced in the applications .desktop file. Their size should be 64x64px, it is okay to just provide one size.

## Filesystem locations

All icons of type `cached` must be placed in `/usr/share/app-info/icons/%{origin}/%{size}/` or `/var/cache/app-info/icons/%{origin}/%{size}/`, where `origin` is the AppStream data origin defined in the AppStream data file (see ), and `size` is `64x64` or `128x128` depending on the size of the icon. And icon might be present with different sizes in both directories.

For example the cache icon `krita.png` of a component in a data file with the origin `jessie` should be stored in `/usr/share/app-info/icons/jessie/64x64/krita.png` (or in the `/var/cache` location).

Legacy Support

In order to support the old icon cache layout, client applications may also look for icons in the folder below the size-directories, assuming that the icons placed there are of size `64x64` pixels.