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Sometimes it happens that you need to take snapshot from your current console (shell) in Linux text-mode. The easiest and the handy way is, using fbcat application.
In order to install fbcat on Ubuntu, type the following command in your terminal
$ sudo apt-get install fbcat
After installation easily you can take snapshot with the below command,
$ sudo fbcat > image.ppm
The only problem is that the output of the file is in ppm format. Therefore, you need to convert the ppm file to the common file extension like jpg, png, etc.
For converting image also there is an application which is called imagemagick and fortunately it is available in Ubuntu repository.
To install imagemagick type the following command in terminal
$ sudo apt-get install imagemagick
Then after installation complete you can convert image like below
$ convert image.ppm output.png
More information is available on the applications man pages.
