You could map the keyboard shortcut of your choice to a (very) short script that goes something like:
activeWinLine=$(xprop -root | grep "_NET_ACTIVE_WINDOW(WINDOW)")
import -window "$activeWinId" $FILENAME -comment $TAGSTRING
# More advanced exif info:
exiftool -keywords=$KW $FILENAME
To make this executable, save it as something like
myscreenshot and then do
chmod u+x myscreenshot
Placing it in your
~/bin/ directory and making sure that that is in your path means it will be executable from whatever directory it is called from.
Then depending on your desktop environment you need to map whatever keyboard shortcut you like to the command
for example in Gnome, select keyboard shortcuts from preferences, and assign a custom shortcut (you decide on the key combination) to the command
If you didn't put the executable in a path on the PATH, then you would have to specify the full path in the command argument, such as
This takes a screenshot of the active window but can be easily modified to take a screenshot of the whole window if that's what you want.
exiftool may also do what you want - perhaps giving more flexibility over the information to store than the comment string alone.
exiftool -keywords=one -keywords=two -keywords=twentythree FILENAME
will add the keywords
three to FILENAME.
Also TAGSTRING can either be set in the script file, or perhaps passed in using a simple zenity dialog, depending on if it will be the same each time or you need to be able to change it.
shutter seems to have a lot of customization options (many more than the stock screen capture tool), including upload! See here for more information.