View Source ExTDLib.Object.BackgroundTypeWallpaper (ExTDLib v0.0.4)

A wallpaper in JPEG format.

Name	Type	Description
is_blurred	bool	True, if the wallpaper must be downscaled to fit in 450x450 square and then box-blurred with radius 12.
is_moving	bool	True, if the background needs to be slightly moved when device is tilted.

More details on telegram's documentation.