Taking screenshots on the Raspberry Pi is useful if you need to keep a record of your project or share details with others. You can capture screen grabs using a command line utility called Scrot.
It is easy to use and provides lots of options. It allows delayed captures and the ability to choose the capture area with the mouse.
If your Pi started on the command line launch the graphical interface by typing :
Once the desktop has loaded double-click the LXTerminal icon on the desktop to open a command window.
The installation can be completed using a standard apt-get call :
sudo apt-get install scrot
Scrot has lots of features you can use but to instantly take a basic screen shot of the whole desktop you can use :
Here is an example (click to enlarge) :
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
Specify Screenshot Filename
To specify a file name and location you can use :
You can change the output format used by changing the file extension. For example :
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 :
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.
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.