ffmongodb-save-imgs man page

ffmongodb-save-imgs ā€” Save PNG files from database images


ffmongodb-save-imgs [-h] [-o dir] [-f] [-d database] -c <collection> items...


This program connects to a local MongoDB database and extracts raw RGB images from a collection (typically recorded via the mongodb-log plugin), and stores them as a series of PNG images.



Show help instructions.

-o directory

Write PNG images to the given output directory.


Use the filenames as stored in the database. If not given the images will be saved as a numbered sequence of the form 00000001, 00000002 etc.

-d database

Name of the database to read from.

-c collection

Name of the collection to read from.


Timestamps and time ranges for which to extract the images. Timestamps are given as the time since the epoch in milisecond precision. If two timestamps are given concatenated by ".." they are treated as start and end times of a time range.

Video from an Image Sequence

You can generate videos from an image sequence for example using a command like this:

ffmpeg -r 24 -b:v 500000 -i openni-image-rgb-%08d.png video.mp4

Create video.mp4 with 24fps at a bit rate of 500kbit from images of the given name pattern. Note that for older ffmpeg version the bitrate must be specified with just -b.


ffmongodb-save-imgs -c openni_image_rgb 0..1355421345807

Extract all images until 1355421345807.

See Also



Written by Tim Niemueller <niemueller@kbsg.rwth-aachen.de>


Documentation by Tim Niemueller <niemueller@kbsg.rwth-aachen.de>


Part of the Fawkes Robot Software Framework. Project website is at http://www.fawkesrobotics.org


04/10/2018 Fawkes 1.0.1 Fawkes Manual