Polycom 1725-11530-310 manual Background bg, This configuration attribute is defined as follows

Administrator’s Guide Addendum for the SoundPoint IP 450

Background <bg/>

This configuration attribute is defined as follows:

Attribute	Permitted	Default	Interpretation
	Values
bg.gray.selection	w,x	2,1	Specifiy which type of background (w) and index
			(x) for that type is selected on reboot.
bg.medRes.gray.pr.x.adj		-3	Specify the brightness adjustment to the graphic.
bg.medRes.gray.pat.solid.x.	any string	White	Solid pattern name.
name			For x=1: White, x=2: Light Gray, x=3, 4: Null
bg.medRes.gray.pat.solid.x.red	0 to 255		The screen background layouts.
			For x=1, red (255), green, (255), blue (255)
bg.medRes.gray.pat.solid.x.	0 to 255
			For x=2, red (160), green (160), blue (160)
green
			For x=3 and 4, all values are Null.
bg.medRes.gray.pat.solid.x.	0 to 255
			Note: The values for red, green, and blue must be
blue
			the same to display correctly on grayscale.

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