How To Take Screenshots On The Raspberry Pi

Scrot Screen Shot Example 1While putting together some future articles I wanted to take some screen shots within LXDE, the Pi’s default graphical interface.

I considered taking them on my PC using a remote desktop connection to the Pi but I thought it might be easier to just take them directly on the Pi as I used it.

To do this I decided to use Scrot which is a command line screen capturing utility.

Installation

The installation can be completed on Raspbian using a standard apt-get call :

sudo apt-get install scrot

Basic Usage

Start the graphical interface by typing :

startx

Double-click the LXTerminal icon on the desktop to open a command window.

Scrot has lots of features you can use but to instantly take a basic screen shot of the whole desktop you can use :

scrot

Here is an example (click to enlarge) :

Scrot Screen Shot Example 1

The default file name convention will give you a date, time and resolution stamped file such as “2013-10-03-221500_1920x1080_scrot.png”.

To take a screen shot after a delay use :

scrot -d 10

where 10 is the number of seconds to wait before capturing the image. The image will be saved in your default user directory (i.e. /home/pi/). To add a countdown you can use the ‘c’ option :

scrot -cd 10

To specify a file name and location  you can use :

scrot /home/pi/myscreen.png

You can change the output format used by changing the file extension.

Advanced Usage

Scrot has a lot of other useful features which can be enabled with additional command line options. These include :

-h    Display additional help
-v    Get the current version
-d X  Add a delay of X seconds to the capture
-c    Add a countdown to a delayed capture
-s    Allow user to specific capture area with the mouse
-u    Capture the current active window
-q X  Specify the image quality percentage X (default 75)
-t X  Create a thumbnail version at a specified percentage size X
-e    Specify a command to run after the image is capture

The -s option allow you to drag an area with the mouse to capture.

The -u option captures the current window. Combined with the -d option you can give yourself a few seconds to select the window you want to capture. In the example below I captured the LXTerminal window I was using to run Scrot :

scrot_example_2

The -t option will create a second image that is a smaller version of the main image. The thumbnail has the same file name as the main image but with “-thumb” appended on the end.

In this example we will get our capture file and a thumbnail that is 25% smaller :

scrot -t 25 myexample.jpg

The resulting files will be myexample.jpg and myexample-thumb.jpg.

Special Strings

Both the -e and filename parameters can take special “format specifiers”. This are replaced with data when they are encountered by Scrot.

There are two types of format specifier. Characters preceded by a ‘%’ symbol are
are interpreted by the standard strftime function. See man strftime for examples. These are commonly used to refer to dates and times.

The second kind are Scrot specific variables and are prefixed by ‘$’. The following specifiers are recognised:

$f  image path/filename (ignored when used in the filename)
$m  thumbnail path/filename
$n  image name (ignored when used in the filename)
$s  image size (bytes) (ignored when used in the filename)
$p  image pixel size
$w  image width
$h  image height
$t  image format
$$  prints a literal '$'
\n  prints a newline (ignored when used in the filename)

For example :

scrot '%Y-%m-%d_$wx$h_scrot.png' -e 'mv $f ~/home/pi/images/'

creates a file called something like 2013-10-03_1920x1080_scrot.png and then moves it to an  images directory.

This entry was posted in Debian, Raspbian, Tutorials & Help and tagged , , . Bookmark the permalink.


5 Responses to How To Take Screenshots On The Raspberry Pi

  1. Flanux says:

    Very usefull !
    I was looking fur this…
    Thanks..

  2. Mikko says:

    scrot is an X11 program, fbgrab grabs a frame buffer, but how do I get a screenshot from
    an egl program such as RPIGears or from hardware decoded video (omxplayer)?

  3. Nate says:

    Hi there! Thanks a lot for the tutorial. You helped confirm that what I was trying made sense.

    Hey, I am trying to take screenshots for Minecraft on the Pi (Minecraft Pi Edition). For some reason, the Minecraft window shows up black when taking a screenshot with scrot. Does anyone know how to fix this? The people I have asked suspected that Minecraft Pi is using OpenGL, so for some reason graphics from the GPU are bypassing whatever scrot is trying to do.

    Hoping to avoid the bootleg record the screen with a smart phone trick . . . thanks!

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>