Picons are channel logos which are linked to one or more TV channels using a service reference or a simplified version of the channel name. They can be installed on the popular Enigma2 satellite receivers, some TV backends for Kodi also support picons. Multiple versions and resolutions are available on the downloads page, which one you need depends on personal preference, used skin or used system/backend.
For Enigma2 receivers using for example OpenVIX, it's easiest to just download the one you want with the extension .ipk. After that put it on a USB-stick and put the stick in your receiver. Next, navigate with your remote to a menu option called "Install local extension", depending on your image or translation. Kodi backends differ quite a lot and it's best to consult the instructions of your backend, you will probably do not want to download a .ipk in this case.
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