The VideoLAN Forums

Hello,

I am searching for a software-plugin for VLC (or other common free software), which can detect movements in videos (Motion Detection).

I have many surveillance videos which I must work through. It would take months to do so with my own eyes.

Isn't there a Plugin/Filter für VLC (, AviSynth, VirtualDub,) which either tells me the positions with changed content or best, directly jumps some seconds before the real movement/change in the video and shows the video from there. Best would be some configurable Setting with trigger threshhold)? Can VLC do 'scene detection', maybe this would do it.

Thank you.

There is already one, by default in VLC.

I would also be incredibly thankful if you would be inclined to consider supporting this feature. Exporting the first frame of every new scene (i.e. upon scene change detection) as an image file, would be an enormous help in identifying added and deleted scenes when comparing 2 videos. (If Motion Detection and Scene Change Detection are considered two differnent things for the purpose of this thread, then please split it.)

Jean-Baptiste, if I understand correctly, this is already implemented?

There is already one, by default in VLC.

So how can the VLC user interact with this motion / scene change detector you refer to in order to achieve the task mentioned above?

If not already implemented, as a feature request I would suggest the following:
in preferences > video > output modules > scene filter add a checkbox entitled "only on scene changes"

PS: two videos to show techniques of scene change detection (although the input video material is not "classical" in the sense that they rather consist of a long tracking shot, instead of classical cinema movie with clear scene cuts, but as they are still interesting to watch, here we go: )

http://www.youtube.com/watch?v=4988BhKUa9Q&NR=1
http://www.youtube.com/watch?v=4esP2nO1_kY

.
If needed, here is open-source code for scene change detection:

http://www.bbc.co.uk/opensource/projects/shot_change/ ( = sourceforge.net/projects/shot-change )
http://www.mathworks.com/products/compu ... hange.html
http://www.catenary.com/howto/motion.html
http://forum.doom9.org/showthread.php?p ... post268534

There is already one, by default in VLC.

where is it?
how can I use it?

modules/video_filter/motiondetect.c
To use it, just select the modtion detection filter in the list of available video filters.

thank you. are you talking about tools > effects and filters > video effects > image modification > motion detect ?

Yes, or via command-line

I am recording output from a security camera.

I would like to only record the frames where motion is detected to reduce the amount of stored data.

I enabled the "motion detect" video effect filer.
But this just seems to add square boxes to the video where it thinks it has detected motion.

In my case (night time scene) it seems to detect picture noise as motion.
Conversely it ignores all the real large-scale motion in my video stream (maybe due to low frame rate?).

Clearly there must be some parameters which apply to the algorithm, such as noise-level (threshold to ignore), integration (of static objects), difference threshold (level or number of changed pixels to detect).

Is it possible to adjust these parameters to suit my video source?

Is it possible to only record the frames where motion is detected (either on the live video or as a post-processing transcode operation)?

Not in VLC, so far.

Hi, for this i use "vlc --video-filter=motiondetect -vvv > modec 2>&1" to redirect full vlc log to a file.
Then i use something like while thrue : tail -n 1 modec | grep 'moving shapes' , to get only the last line of the output of the motiondetect module.
If the last line is not equal than the line before, then something have move, so you can start the grabbing .

the answer from zozizozu is it also applicable in Windows? I've tried to use it, but the second part didn't work.

Hi. I'm sorry, it will not work on windows except if you install GNU executables tail and grep , you can use mingwin for example.
I've modified the code of this module so it can resend datas to UDP, but it seams videolan's developpers not want that : https://mailman.videolan.org/pipermail/ ... 11433.html
You can ask for this new feature on https://forum.videolan.org/viewforum.php?f=7 , or compile VLC by yourself using my modified code : https://guest:nopw@trac.ddrdev.fr/utils ... ondetect.c

Regards

Don't forget that Windows-10 also supports Linux commands now, through its Ubuntu subset.

Just open a command prompt and enter: bash

For further reading see https://www.howtogeek.com/249966/how-to ... indows-10/