23 June 2013

• screenshot.java
  

  // screenshot tool for "ZTE FTV Blade" (6/23/2013) // - grabs framebuffer /dev/graphics/fb0 (needs "chmod o+r") // - converts each of the 800x480 pixels from rgb565le to rgb888 format // - rotates 180° (frambuffer-->image) // - for use in "Terminal IDE" (or Linux, copy raw data to "/dev/graphics/fb0") // https://play.google.com/store/apps/details?id=com.spartacusrex.spartacuside //

  Browsers cannot display Portable pixmap fb0.pnm directly, but your image viewer can.
  Screenshot takes less than 1.5 seconds (on the device).
  (converted to ".png" with "gimp", rotated by 90° because of landscape view, click for 100% view)
     

• I read about doing a screenshot via adb (Android Debug Bridge).
  Since this would allow to take Screenshots even when booted into ClockworkMod Recovery
  I was really interested. The method to convert the raw framebuffer data pulled from
  /dev/graphics/fb0 was to use ffmpeg tool (from http://www.ffmpeg.org/).
  Now there were 115 conversion formats available in ffmpeg, and those I did find
  in postings did not work for my ZTE FTV Blade (most result in "funny" images).

  I just ran a bash script iterating over all 115 formats, doing the conversion, and viewing the result.
  The first format showing me the screenshot correctly was "rgb565le".
  My script pull-fb0 does grab the raw framebuffer, then converts it to a PNG file,
  then rotates by 180° by netpbm tools and finally displays the result in gimp.
  The screenshot on the right from ClockwordMod Recovery v5.0.2.0 could not have been done otherwise.
   

  $ cat ~/bin/pull-fb0 #!/bin/bash adb pull /dev/graphics/fb0 /tmp/fb0 2> /tmp/fb0.log ffmpeg -vframes 1 -f rawvideo -pix_fmt rgb565le -s 480x800 -i /tmp/fb0 /tmp/fb0.png 2>> /tmp/fb0.log pngtopnm /tmp/fb0.png | pamflip -rotate180 - | pnmtopng - > /tmp/fb0.rot.png gimp /tmp/fb0.rot.png $

   
   

• Surprise, Cyanogenmod 7.2 does provide Screenshot facility!
  Just pressing the Power button opens the Phone options menue for Screenshot.
  This screenshot was taken after uninstall of Screenshot UX in Google Play:
  
   
• Screenshot UX is not useless, it allows for modifications before storing.
  And for delayed Screenshots -- the second could not have been done without:
   
  

• successfully installed Teminal IDE (needing 150MB free data space).
  With its own full ANSI keyboard, and it works!
  
  Terminal IDE on Google play
  http://code.google.com/p/terminal-ide/
  Terminal_IDE_Help.pdf (under "Downloads" tab)
   
• successfully increased data partition to 279MB(!) from 162MB
  Gen2-v2a.zip from ZTE Blade TPTs
  now:
  
  before:
  
   
  Most important was to combine different postings in order to find out how!
  1) power off the phone
  2) remove battery(!)
  3) reinsert battery
  4) Press "Vol Up" AND "Menu" key
  5) Power on phone

  This way whatever is in "/image" folder of SD card gets flashed to the device (be careful!)
   

• successfully upgraded to Android 2.3.7 (cyanogenmod 7.2) from 2.2.2 in order to install "Terminal IDE"
  as mentioned in "programming" part of 3rd "myAndroid" posting.
  
   
• Upgraded to ClockworkMod Recovery v5.0.2.0

• myAndroid -- DataPower WebGUI posting
  
   
• myAndroid -- why rooting / programming posting
  

• myAndroid -- software posting
  
   
  From that posting, nice ebook reader screenshot:
   
• myAndroid -- hardware posting