AVC761: Tuning Motion Detection for Movement not Brightness

[todd2 0]

I know there are a few 'knobs' that you can set for the motion detection.

Is there any way to make it more sensitive to movement and less

sensitive to brightness? By this I mean if the whole image gets brighter

or dimmer, the motion detection trips, even if nothing is moving.

 

When I inspect the tripping events, all of the ones that I don't expect

(i.e., not me coming or going) are bright/dim pulsations from sunlight

or clouds. (The blinds are already closed as much as possible.)

[scorpion 0]

LS (Level of sensitivity)

 

This is the sensitivity of comparing two different images. The lower the number the higher sensitivity for motion detection. Default is 7.

 

 

SS (Spacial Sensitivity)

 

The Sensitivity towards the size of the triggered object on the screen (the number of motion detection grids). The smaller the value the higher the sensitivity for motion detection. The highest sensitivity is 00. Default is 03. (Once in object is detected more than 3 grids then the system will trigger).

 

 

TS (Time of sensitivity)

 

The sensitivity regarding how long the object gets triggered. The smaller the value, the higher motion detection sesitivity will be. The highest sesitivity setting is 00. Default is 02

 

 

RE (Reference)

 

The value of RE is a reference for detection. The default value is 10, which means the DVR will compare 10 continuous images at one time according to the sensitivity of LS, SS, TS simultaneously. The bigger the value, the higher sesitivity for motion detection.

[djg000111 0]

I have a similar problem with setting the motion detection. I do not have any understanding of TS (Time of sensitivity). I understand the units for SS and RE. I have a good feel for LS. Does TS have meaning if it is greater than RE (for example, TS=15 and RE=10)? Does fps setting alter TS? Does RE alter TS? Are the TS values linear (for example, TS=1 means any movement longer than 1 msec triggers motion alarm and TS=15 means any movement longer than 15 msec triggers motion alarm)? What does TS use as a reference?

[scorpion 0]

I am a residential installer, and I do not have a client base that would pay to have these settings "dialed" in.

 

I do not have any notes on how the combinations affect (or is that effect) the detection.

 

I wish I could help you more.

 

 

http://www.optexamerica.com/productlist.aspx?l1=2

[SteveFD 0]

I only have a vague idea of what the motion dection parameters are doing but what I do find useful on the AVC 761 is to view the motion dectection setup on the monitor, the screen where detected motion flashes grey in the grid(s) detected and then use video viewer to play with the parameters. The only annoyance is that you have to press enter again on the remote when the screen times out. Not an exact science but it has enabled me by trial and error to filter out a lot of false detections, (shadows of brances, bird, etc.) and still pick up people everytime.

[scorpion 0]

Well said!

[djg000111 0]

Using the grey flashes during motion detection setup is a good technique for masking areas were you have motion that is not of interest. This week, one of my cameras at night continuously detected motion. The problem was created by my neighbor hanging party balloons on a street lamp post. At night when the street light was on, the balloons dim shadows from the street light were in my camera view. Any wind made the balloons move. If I did not have the grey flashes available, I would have never known what created the problem.

 

I still do not understand how TS relates to motion detection. I now have TS for all cameras set to 4 and use the other settings to tune for motion detection and not light variation detection.

[Sam007 0]

anyone ever tune up this DVR motion wise to "not" trigger on dust particles, light snow/rain or general nightime picture noise when using IR camera's yet still have fairly good sensetivity?

 

Is this even possiable?? hehe

 

Actually, I've only had good experiances with PC based cards for these issues.

[DaveM 0]

I ended up disconnecting the IR LED's and putting up an external IR illuminator placed about 3' away from the camera. That did the trick.

[tondar 0]

did the remote IR's help with snow/rain? that's a problem I'm currently having

[DaveM 0]

Yes, disconnecting the built in IR and putting up stand alone illuminators made all the difference in the world. Put the IR as far away from the camera and as close to the target as you can to reduce the "back scatter". Just putting it 3 feet off to the side of the camera worked for me with rain and light fog, no snow here in Los Angeles. It looked like a swarm of bees before.

[Sam007 0]

Ok, i've been playing around with these motion settings for a few days now. I found that keeping the SS setting at "3" and increasing the TS to "6" or higher will decrease the false alarms due to dust/rain/snow depending on how severe they are. If the TS is set high, it decreases the chance that motion will trip due to rain/snow/dust particles being in 3(SS) of the grids for under a second. If you look at the detection screen during the night, you'll notice that the dust particles will trip multiple grids at the same time but only for a split second depending on weather conditions and how windy it is. Increasing TS will allow these particles to have a higher time threshold for a motion event to happen. If the particles are slow moving and stay in the FOV longer, the motion will trip.

 

I am now playing around with the RE value...i currently have mine set at 35 and have been monitoring it for a few days.

 

 

If anyone else has any info on tuning the motion detection settings or experiances, that would be great as there is little info on how these settings affect the detection in the real world with different camera types and lenses.

[scorpion 0]

I have never seen snow in my cameras! LOL!

 

If I do I think there is about 20 women who will knock on my door to collect on my "Yes, when it snows in Florida I will marry you"!

 

You will have to forgive me, but I am going to keep praying that it never snows in Florida! LOL!

 

 

Thanks for the heads up! We appreciate your time, and effort!