Cheap megapixels cameras in PTP mode with Zoneminder?

[vincecate]

It seems like it should be possible to use regular still cameras with a USB port from zoneminder. Is this possible? Is it common?

There is a "Picture Transfer Protocol" which still digital cameras use.
http://en.wikipedia.org/wiki/Picture_Transfer_Protocol

Linux seems to support PTP:
http://en.wikipedia.org/wiki/GPhoto
Works with 800 cameras
At least some of these can do remote control/capture

A highly rated Canon PowerShot A550 7 megapixel camera for $142:
http://www.amazon.com/gp/product/B000MF ... 69-0624720

gphoto2 --list-cameras
Shows Cannon A510, A520, A530, A540 work in PTP mode.
I am going to guess that A550 works too it is just not on the list yet.

This price for 7 megapixels is far better than the prices on megapixel security cameras I have looked at. I suspect that snapshot cameras sell in such huge volumes that what you get for your money is far better than when you buy security cameras. Unlike the $1200 cameras it may not do high framerates, but if I could get 2 or 3 per second I would be happy.

I ordered one of these A550 cameras. I need a new digital camera anyway, so if I can't get it to work with Zoneminder it is not a waste. At that price I could get one for every computer in the office that is near a window and have plenty of eyes at night. Outside the building is well lit at night, but will have to see if it is enough. Is this reasonable?

-- Vince

[vincecate]

http://gphoto.wiki.sourceforge.net/Capture

This says that gphoto is able to capture from lots of Canon Power Shot cameras. It does not list the one I ordered, but this looks like good news to me.

[vincecate]

I have a Sony MVC CD400, which is not listed as supported but I tried it anyway. The command is just:

gphoto2 --capture-image

But it is not supported on my camera. I was able to copy images off.
But I think this should work on the A550.

With some of the cameras you can capture the image and send it over the USB without ever saving it to flash. This should improve the frames/second number. Not sure if this works with the A550.

So I think it will work. The big question is what the frames/second or seconds/frame number will be.

Also looking at the Canon PowerShot A640 10MP. This is 10 megapixels for $270. Nice thing is it is listed to work for sure. Again, just don't know how fast it could take pictures in the PTP/USB mode.

http://www.amazon.com/Canon-PowerShot-D ... 69-0624720

-- Vince

[vincecate]

So it seems standard for snapshot cameras to open and close a shutter with every picture. If you take a picture every second or so your camera will not last very long.

It seems with Canon it is possible to leave the shutter open using software at:

http://capture.sourceforge.net/

[vincecate]

The problem seems to be that these cameras have lots of moving parts.
Iris/aperture control
zoom
focus
lenses come in for compact shape when not in use
etc.

It is not clear you can turn off all of these things on any of the snapshot cameras and still take good pictures.

If anyone knows of a cheap multi-megapixel camera where you can turn off mechanical things and still have a computer take pictures, please post which it is.

[vincecate]

One idea would be to use a cheap webcam to detect motion and then when there was motion use a 10 MP snapshot camera to take some pictures too. So the total number of pictures from the 10 MP camera could be kept low enough that it did not break too fast. May try this.

[nakedfarmanimals]

Cheap webcam?

Why not a Floodlight with a Motion Detector kit?

http://www.homedepot.com/webapp/wcs/sto ... tion+flood

Wire the event trigger onto the light's power lead (through a down-stepping relay, of course) so that not only do you have something that can see motion, but have more than enough light to take the photo.

Of course, if you get any really good "oh, crap!" looks caught on film, please feel free to share.

[clipo]

This is an interesting idea, has anyone else progressed it.

Another option now is to use a mega pixel webcam to do the job.

I'm really interesting is trying to make some high resolution camera for Zoneminder since the current purpose built security cameras only do 640x480 and at that resolution its hard to make out fine details of the scum bag who nicks your stuff.

[vincecate]

Here is what we ended up doing. It is kind of cool really. We used the webcam for motion detection and then took high res pictures when there was some motion. I really think a camera could be programmed to use the viewfinder mode to look for motion and then take pictures. Somebody ought to do that. Oh, and I have seen wildlife cameras that sort of do this, though not 10 megapixel.

http://docs.google.com/View?id=ajdppnp7smhr_36f8pffd

-- Vince

[kingofkya]

this thread effective solves the quality problem with cctv ocr for plates great idea.

[coke]

I'd been thinking along these lines for a while, but one of the reasons I never pursued it was the distance capability of USB cameras, and the vast distances apart my cameras are. (13.5 story square city block). Do you have computers nearby the usb cams, or are you using some sort of extension? Any idea on the max range that actually works?

[clipo]

The max chain length for USB is 5meters, and Ive had a USB webcam running ok and a 5m long extension cable, even with hubs you cant go longer due to propagation delay.

I was thinking of some small mini ITX or even Atom systems with one of two mega pixel webcams and then networking them back to a central system.

As for optical range of a webcam they are ok, my camera was looking at targets about 2 - 3m away.

The big question at the moment is a good, cheap enough webcam that is linux friendly.

[kingofkya]

Now we gust need some one to develop a usb to network module.
http://www.gumstix.com/
would be a place to start.

Also as a side note if you have ever seen the trafic cams that send you a ticket automatic. They use still cameras just like this.


another interesting though
take a look at http://sourceforge.net/projects/tesseract-ocr/