It can be easily implemented as a filter[1][2]. If you need to use it via command-line you can save the current buffer as a tempfile[3], call your CLI with the

It can be easily implemented as a filter[1][2]. If you need to use it via command-line you can save the current buffer as a tempfile[3], call your CLI with the tempfile path and read the tempfile to use as the new buffer. It's even simpler if your CLI can take a stdin argument, since you can just pass the buffer as a stdin parameter. Thumbor's filter infrastructure allows you to change the image incrementally. [1] https://github.com/thumbor/thumbor/wiki/Brightness https://github.com/thumbor/thumbor/wiki/Brightness [2] https://github.com/thumbor/thumbor/blob/master/thumbor/filters/brightness.py https://github.com/thumbor/thumbor/blob/master/thumbor/filte... [3] https://docs.python.org/2/library/tempfile.html https://docs.python.org/2/library/tempfile.html