Tweak Screencapture Behavior (MAC)

Normally, we will use keystrokes Cmd-Shift-3 or Cmd-Shift-4 to take snapshot with Mac default screencapture utility. And new in Snow Leopard, we will end up having a PNG image file automatically stored inside our Desktop folder with the name Screen shot

Those behaviors mentioned above are the default ones. We can of course easily change those with simple command lines on the terminal…

1. Change Screencapture Filename
   defaults write com.apple.screencapture name "New Name"

   
   killall SystemUIServer

   You can change the value "New Name" to the name of your liking. And if you put the name as empty string (i.e. ""), you will get your screencapture named with the format: [current date] at [time], e.g. "2009-10-20 at AM 03.02.57".

2. Change Screencapture Location
   defaults write com.apple.screencapture location "New Location"
   killall SystemUIServer

   Hint: You can drag-drop the folder to Terminal pane to get the folder location.
   As seen in both command lines, the second line killall SystemUIServer is needed and used to restart the screencapture application. Only after restarting, changes will take effect.

3. Change Screencapture File Format
   defaults write com.apple.screencapture type [new format]
   killall SystemUIServer

   These file formats are available: PNG, PDF, JPG, JP2, GIF, TIF, BMP, PICT, and TGA.
   Note. Replace the [new format] with one of those available formats, e.g. JPG.

4. Disable Window Shadow
   When we used key combination [Cmd-Shift-4] + [Space], we will be able to capture a snapshot of window along with the shadow. The following command lines are used to disable the shadow.
   defaults write com.apple.screencapture disable-shadow -bool true
   killall SystemUIServer

   You can change -bool true to -bool false to enable back the shadow.

5. Capture from Terminal Command
   One of these command lines can be used to capture from terminal:
   screencapture -c
   screencapture -i ~/Desktop/snapshot.png
   screencapture -io ~/Desktop/screenshot.png
   screencapture -M ~/Desktop/screenshot.png
   screencapture -P ~/Desktop/screenshot.png
   screencapture -t png ~/Desktop/screenshot.png
   screencapture -T 5 ~/Desktop/screenshot.png
   screencapture -x ~/Desktop/screenshot.png

   The usages of each command line can be checked using: man screencapture

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