#7229 NORM Never A: Ambient light detection for power saving

[Zarro Boogs per Child]

#7229: Ambient light detection for power saving
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 Reporter:  erikg                |       Owner:  erikg         
     Type:  enhancement          |      Status:  new           
 Priority:  normal               |   Milestone:  Never Assigned
Component:  power manager (OHM)  |     Version:  Update.1      
 Keywords:                       |    Verified:  0             
 Blocking:                       |   Blockedby:                
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 See [http://wiki.laptop.org/go/Ambient_light_detection].

 By using the XO's camera as an ambient light detector and using that data
 to control the backlight brightness, it may be possible to make the XO's
 battery life longer when used by kids (who may not walk around adjusting
 their backlight to optimal power-saving levels all the time).

 Process:

  * Every N (60?) seconds, take a picture.
  * average the luminance of the image and square that number. (Why square?
 [http://en.wikipedia.org/wiki/Luminance See the formula] on how luminance
 is calculated.)
  * Use this number (the square of the luminance) to control the backlight.
  * Allow the user to manually override the automatic backlight setting,
 and to easily turn the auto-backlight-setting mode on and off.

-- 
Ticket URL: <http://dev.laptop.org/ticket/7229>
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