#9853 NORM 1.5-har: XO-1.5 low camera image quality

Zarro Boogs per Child bugtracker at laptop.org
Thu Jan 28 17:31:47 EST 2010


#9853: XO-1.5 low camera image quality
--------------------------------+-------------------------------------------
           Reporter:  dsd       |       Owner:  dsaxena       
               Type:  defect    |      Status:  new           
           Priority:  normal    |   Milestone:  1.5-hardware-C
          Component:  kernel    |     Version:  1.5-B3        
         Resolution:            |    Keywords:                
        Next_action:  diagnose  |    Verified:  0             
Deployment_affected:            |   Blockedby:                
           Blocking:            |  
--------------------------------+-------------------------------------------

Comment(by Quozl):

 Tested again using a similar technique in #9576, taking two photographs
 using Record on XO-1 SKU39 and XO-1.5 C1 at a subject illuminance of 30 lx
 and 9500 lx.

 Only the dark subject showed a significant difference, and the difference
 was a darker image and increased noise.

 Tested again using !OpenFirmware "test /camera".  On the dark subject, the
 images were about equal.

 Taking the XO-1 build 802 behaviour as a baseline, the observed
 differences against XO-1.5 os200 are:

 ||'''driver'''||'''size'''||'''orientation'''||'''noise'''||
 ||!OpenFirmware||half||ok||ok||
 ||kernel||ok||left for right swapped||higher at low light levels||

 So wishlist for kernel driver is:
  * swap left for right,
  * configure sensor to increase gain.

 I've reviewed the kernel source via-camera.c, and it has flip_image for
 vertical flip, but no parameter for horizontal flip.

 I might be misunderstanding things ... it might be the role of the user
 space application to configure the sensor for increased gain.  There was
 nothing obvious in Record that does this.

-- 
Ticket URL: <http://dev.laptop.org/ticket/9853#comment:7>
One Laptop Per Child <http://laptop.org/>
OLPC bug tracking system


More information about the Bugs mailing list