An alternative I used to use when I wanted this feature:
`while [ 1 ];do vardate=$(date +%d\-%m\-%Y\_%H.%M.%S); screencapture -t jpg -x ~/Desktop/project_name/$vardate.jpg; sleep 10; done`
`while [ 1 ];do vardate=$(date +%d\-%m\-%Y\_%H.%M.%S); screencapture -t jpg -x ~/Desktop/project_name/$vardate.jpg; sleep 10; done`
ScreenNinja seems to also provide a number of features that would prob take a while to implement if you wanted them