Yealink SIP-T54S Administrator's Manual page 209

When the DSS key list is unfolded (tap More key when the phone is idle):
When the DSS key list is folded (tap Hide key when the DSS key list is unfolded):
The wallpaper will display on the entire screen. Note that the line key labels, time and date,
Note
icons, and soft keys will display over the wallpaper, while they are invisible on the image logo
screen.
The wallpaper image format must meet the following:
Phone Model
SIP-T54S/T52S
SIP-T48G/S
Format Resolution
<=4.2
megapixels
*.jpg/*.png/*.
bmp/*.jpeg
<=2.0
megapixels
Configuring Basic Features
Single File
Note
Size
<=5MB
2MB of space
should be
reserved for the
phone
<=5MB
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