text: Q:
  
  How do I format an image for display on a Cisco SPA 303
  
  In the manual it says I have to create a 128x48 bmp image with 1-bit per pixel, but when i upload it to the phone, it merely displays a full black image.
  I've tried:
  
  creating the image with gimp, saving it as a 1-bit indexed bmp.
  convert input.bmp -colors 2 -type Bilevel -depth 1 output.bmp
  
  the latter produces the following output when calling identify output.bmp:
  output.bmp BMP 128x48 128x48+0+0 1-bit sRGB 2c 914B 0.000u 0:00.000
  Which looks completely up to specs to me.
  Can someone tell what i'm doing wrong, or give me pointers to debug the problem.
  
  A:
  
  I had the same problem, and then I took a look at the example image they provided in their guide (here: https://supportforums.cisco.com/document/51231/configuring-bmp-logo-spa303-and-spa50xg-ip-phones) by using identify.
  Turns out their bmp is BMP version 3.
  So I re-encoded my image from a monochrome png using :
  "convert test.png -depth 1 -type Bilevel BMP3:test.bmp"
  and IT WORKED HALLELUJAH!
  So I feel like the 5 hours I wasted on that are completely justified.
  Peace out.
  
  