How can I hide defined image area

Question

How can i hide peoples-area in the motion-program or config.file?

I have create a Image called snapmask.pgm in black-white-binary-format with black Areas for invisible and White area in visible. I want to hide so people's

In the Motion.conf is an Option mask_file , but this is for Motion-detection and not for my. What should I do? Does anyone have an idea how this might be with the config-option on_picture_save? maybe a overlay at the actual snapshot-image with the transparent snapmask?

No errors

Environment

Motion version:	3.2.12
ffmpeg version:
Libraries:	ffmpeg, mysql, postgresql
Server OS:

-- UweHeidrich - 20 May 2013

Answer