Need to position PTZ camera in absolute coordinates

[juannm 0]

Hello all, after a lot of searching I have found this interesting forum

 

I'm working in a video surveillance system and need some help with the PTZ camera movement: the camera should be able to move automatically to a defined X and Y point, and maybe a Z value indicating a zoom value (but tha's only an extra, not really needed).

I have started using the Pelco D protocol but it won't let me do such a movement, because it seems to be focused on having a physicall person controlling the system and commanding the camera to the desired position. But there will be no person controlling the camera.

 

So they will be welcome any comments about cameras and protocols that will allow me to do such kind of camera control.

 

Thanks for reading

[bike_rider 0]

You need a camera that supports presets. These are numbered absolute locations, including zomm factor. On the Pany PTZ, you set the camera the way you want and then "set" the preset location.

 

Then you use the command for "goto preset 1" or preset "12", etc.

[juannm 0]

I have already tried using presets, in fact that was my first idea, but at least in Pelco D protocol the number of presets is only from 0x01 to 0x20, that is only 32 presets, which is an insufficient number because what I would want to achieve is doing automatic object tracking.

 

The system performs movement detection over the image received from a still camera, and extracts a pair of coordenates (X, Y) which indicates the center of the object moving. Thus, I'd like to move automatically the PTZ camera to that point. That is not achievable using presets

[bike_rider 0]

OK, back up and tell us more about the application. Can't offer any more advice without more details about the need.

[juannm 0]

Sorry for the initial lack of detalis, here I go:

Two cameras are placed together and are conected to a computer, where there is a image processing software installed. One of the cameras is fixed and is recording a scene, for example an empty room. Then a person enters the room, this is what should happen: the image captured from the f ixed camera is sent to the computer, where it is processed and moving objects (the person) are detected - so the image processor generates a X,Y coordinates indicating where is (more or less) the center of that object.

So at this point, the PTZ camera (which has less angle of vision than the fixed one because I have set it to, say, 50% of its maximum zoom) should move to that point the processor indicated. Well, actually it should move to that point having in mind the little difference that exists between the point of view of the two cameras, but that is just a mathematical calculation, not important for this topic.

 

From the begining I have tried two techniques: first using presets: it would not be a true object tracking, but the PTZ camera would move from position to position trying to follow the object. But the limitation of only 32 presets for a scene of almost 130º horizontal and 80º vertical makes it a no way.

 

After that I have been "calibrating" the PTZ camera so I calculate my own presets: first measure the time it takes to travel from a fixed point to another, in horizontal movement, and then do the same in vertical. So now when I want the PTZ to go from one point to another, I can "guess" how many time the camera should move in vertical and in horizontal to reach that point. The problem is, maybe you are alerady thinking it, this method is too way inaccurate, because it depends on de TIME (reaction time, the camera seems to be slightly faster when its motors are cold, etc) instead of the distances.

 

So after trying out ideas 1 and 2, I'm stuck and I need to know if there exists a PTZ control protocol based on distance instead of based on time.

Edited January 23, 2008 by Guest

[Rooney 0]

What you want is a camera that has the ability to "slue to cue".

Example,

We install cameras that are tied into a ground radar system. When the radar finds a target ("cue") it relays the coordinates to the camera which will "slue" to the target.

 

Here are some companies that have products that may meet your needs.

 

RVision, Inc.,

EMX Inc.

Flir

Directed perception (they sell pan/tilt units with absolute coordinate software.)

[bike_rider 0]

Geovision also does this - one wide angle camera is used to guide a narrow angle camera. I don't know how they do it, but I think that they only support Pelco PTZs, so there may be some aspect of the protocol that they need. OTOH, they may be doing some image matching to aim.

[juannm 0]

What you want is a camera that has the ability to "slue to cue".

Example,

We install cameras that are tied into a ground radar system. When the radar finds a target ("cue") it relays the coordinates to the camera which will "slue" to the target.

 

Here are some companies that have products that may meet your needs.

 

RVision, Inc.,

EMX Inc.

Flir

Directed perception (they sell pan/tilt units with absolute coordinate software.)

 

Hi, thanks for the info. The first ones seem to focus on infrared cameras, but the last one could have the cameras I'm looking.

 

On the other hand,

Geovision also does this - one wide angle camera is used to guide a narrow angle camera. I don't know how they do it, but I think that they only support Pelco PTZs, so there may be some aspect of the protocol that they need. OTOH, they may be doing some image matching to aim.

 

I have been reading about Geovision and they seem to do exactly what i'm trying, that is, object tracking. It is of interest this answer found on the FAQs:

Q: Which PTZ domes support Object Tracking feature?

A: We currently support Pelco Spectra III, Sensormatic (Ultra VI) and MESSOA (SDS600 series) for Object tracking function.

 

So that camera models must have the needed features for implementing such a tracking system.

 

 

I am surprised on how dificult is to find a ptz camera which is able to do something as simple as going to a determined pan and tilt (but unknown beforehand) no matter where it is looking at before moving. But thank you very much, your help is appreciated

Edited January 29, 2008 by Guest

[survtech 0]

Using "P" protocol, Pelco Spectra IV SE cameras can accomodate up to 256 presets with a +/- 0.1 degree accuracy.

 

See the spec sheet here: ftp://www.pelco.com/ProductSpecs/Pelco_Spectra_IV_SE_Series_Dome_Systems_spec.pdf

[rossewij 0]

We work on a project also requiring absolute (pan tilt angle) positioning combined with a large camera housing. After some surfing on the web, we found the following units that might be usefull for such applications:

 

1) 2Bsecurity PT3001

2) eneo-security VPT-501, VPT-601, VPT-651

3) Videotec Ulisse (Maxi)

4) Dennard/dedicated micros infinity (small)

 

If someone else knows/found other units with abolute positioning (Point&Go) that can be combined with a large camera housing, please let me know.

 

Marcel Rossewij

[joelind 0]

Ulisse Maxi works fine. Both through Sensormatic or PelcoD protocol. That's very precise. For instance the minimum pan speed I computed is about 0.05 degree per second. But it may be even more accurate (I'm not sure I was at full zoom)

 

Pelco domes (Spectra IV) are working fine too. But there you cannot change the optical components.

 

For the protocols, I know that PelcoD, Sensormatic, Bosch are supporting Absolute Ptz. Sensormatic and PelcoD also support requesting current device position. Which doesn't seem to be the case from what I see in Bosch SDK.

[shockwave199 0]

Seems like a lot of work for auto tracking. Look at my vids on my auto tracking camera. Problem solved.

 

t5twk206J0s

 

3nZY4LPlsJo

 

[hfuertes 0]

Software for position PTZ CAMERA in absolute coordinates

Dear Sirs.

I did development the application for to position 2 cameras through PELCO protocol using the google earth. The cameras with long range can be oriented to objetive according to absolute position (latitude and longitude) using the google earth as tool graphic. In reality my application read the NMEA data of any radar of surveillance and present the targets in google earth software, also can oriented the camera where the user wish making click over google earth. Any questions write me to hfuertes@yahoo.com. My phone number is 51 990195905.

Best Regards

Henry Fuertes