USB Cameras for CCTV

[Ferrino 0]

I'm currently looking to put together a residential IP camera based system which will record to a PC server I have running at home (running something like Blue Iris). I was wondering if it is possible to use USB cameras (i.e. webcams etc.) instead of dedicated IP cameras, considering the server will be up 24/7?

 

What I prefer about USB cameras is the smaller size and the fact that they are cheaper and can offer high resolution. What I'm not so sure about is the limit of the cables their signal can be transmitted along. What is the state of the art of running a USB signal along CAT5 network cable? Is it do-able for runs of up to 100 feet?

 

I appreciate that there are other limitations of USB cameras - such as night vision etc., but I'm interested to learn if a USB-camera based residential setup is achievable with CAT5.

 

Thankyou very much!

[Soundy 1]

It's been tried several times over the years - if you search back through the forums, you'll find it rarely produces acceptable results.

 

USB cables are limited to 5m/15ft. without using active extenders of some sort. If you do use USB-over-Cat5 extenders, you'll have to power the remote end, as they don't transmit power over the UTP.

 

I wouldn't use it for anything other than experimentation... certainly wouldn't want any actual security application to rely on a webcam.

[pkoi 0]

Benefits : High resolution webcam have a MUCH MUCH better quality/cost ratio than IP cameras.

 

I lately got myself a few Msft Lifecam studio, 1080p@20fps. for less than 50$

 

The problems are :

* USB max cable length, require powered extender or usb over cat5,

 

* Compression, I'd be looking for GPGPU encoding or this as it use ~60% of a quad-core CPU for h.264. (the Logitech c910 has built-in hardware h264)

 

* Software support is rather poor, Those I've experimented with, Luxriot, i-Catcher, and iSPY (open source)

 

When buying 600+tlv analog cameras I'm always worried the DVR would not be able to support it and I'd be stuck using it at 480tvl

 

It look like this 45$ webcam has as much resolution as 8 x 480tvl analog cams.

[Soundy 1]

Benefits : High resolution webcam have a MUCH MUCH better quality/cost ratio than IP cameras.

Resolution does not automatically equate to quality.

 

When buying 600+tlv analog cameras I'm always worried the DVR would not be able to support it and I'd be stuck using it at 480tvl

The 480 vertical resolution is a limitation of the NTSC analog video standard.

 

It look like this 45$ webcam has as much resolution as 8 x 480tvl analog cams.

It looks that way, doesn't it? Check the specs, though: a lot of "HD" webcams actually use low-resolution sensors and generate an HD image through interpolation.

 

Webcams typically use very cheap plastic lenses in front of very tiny sensors, meaning very low image quality regardless of resolution - doesn't matter what the resolution is if you don't have a clear image projected on it. The small sensor also means very poor capability in low light - "night vision" isn't an answer, it's just a gimmick.

 

What happens if you want a wider shot than your webcam provides - can you swap the lens? What if you want a lot closer shot? Digital zoom isn't an answer - can you swap the lens?

 

If a $40 webcam was really that great for security uses, you think you'd see them used a lot more, wouldn't you?

[pkoi 0]

I was specifically talking about microsoft Lifecam Studio and Logitech c920 c910 c905.

 

These are true 1080p sensors with top notch glass lens (Usually Carl Zeiss), autofocus.

 

If you want my take on the state of the CCTV economy, It's bad,

 

Analog cams are old piece of **** and the newest IP/Megapixel/softwares lock-in are shady and price gouging scams.

[pkoi 0]

If a $40 webcam was really that great for security uses, you think you'd see them used a lot more, wouldn't you?

 

I've been learning about CCTV systems for ~2 years and I'm appalled by slow progress and the price of improved products.

 

This webcam was released about 3 months ago at MSRP of 100$, it is now selling at ~50$ shipped.

[MaxIcon 0]

What's the Lifecam's sensor size? It's not easy to find that in the specs, so I'm not sure what to compare it to. How does the image quality compare to a middle-low IP cam like a Vivotek, which is a good bit more expensive than a $50 webcam? That's a pretty key piece of data.

 

Regardless of the lens quality, you can't change it without a custom adapter. It's designed to show headshots of someone sitting in front of the cam, so is pretty wide-angle.

 

What is the F-stop and lens size? Doesn't seem to be in the specs. Again, hard to compare. I don't know about the Lifecam, but the webcams I've used don't have great dynamic range (shadows don't have much detail), and don't handle widely varying lighting well (washed out vs too dark). Maybe the cams you mention are much better.

 

It has a built-in non-switched IR filter, so that limits it a bit as well. You could probably remove the filter to use with IR, but then you'd have color distortion.

 

I suppose you could come up with a way to mount it in an external enclosure, as long as it's within 15' of the PC.

 

The differences between a proprietary USB interface and an IP interface have been discussed before, so we'll leave that.

 

So, you could use one as a security cam if you don't mind it being within 15' of the PC, don't need IR illumination, don't care about changing the viewing angle, and don't need to use it outdoors.

 

I just don't see it replacing any outdoor IP cams more than 15' away from the NVR.

[pkoi 0]

The sensor must be 1/3" , 75° diagonal field of view

 

With 1080p I'd rather lens be as wide as possible anyway.

 

My main problem right now is the software, it require a lot of processing power to compress the stream, If I could find a way to use a CUDA enabled encoder.

 

For USB length as I said I'm using powered extender or USB over cat5. 15ft is the spec but 20ft + is possible.

 

IR filter : There are various astronomy website that have dissembled this webcam to convert it for astronomy uses, removing the IR filter in the process.

 

I'm currently looking at a Logitech c920 (75$) which has h.264 hardware built in.

[Soundy 1]

There are USB over UTP extenders that will get you hundreds of feet.

 

They also cost more than most IP cameras.

 

I'll say it again, if USB webcams worked so well as security cameras, you'd see them used a lot more. If I could sell a customer an HD camera for $50, my life would be easy. Fact is, they just aren't suitable in the vast majority of security uses, for the MANY reasons outlined above.

 

Oh, and I would be really surprised if that camera has a 1/3" sensor. Frankly, I'd be surprised if it had a 1/4" sensor. Number of pixels is never representative of sensor size - just look at your average 8MP smartphone camera these days: my HTC does 720p video and it would take ten of its sensors to cover a 1/4" CCTV camera's sensor.

[pkoi 0]

There are USB over UTP extenders that will get you hundreds of feet.

They also cost more than most IP cameras. ???

USB over cat5 doing 150ft are 10$ at monoprice and 65ft Active Extension / Repeater Cable are 20$ http://www.monoprice.com/products/search.asp?keyword=usb+extender&x=14&y=5

 

I'll say it again, if USB webcams worked so well as security cameras, you'd see them used a lot more. If I could sell a customer an HD camera for $50, my life would be easy.

I'll repeat it again, "This webcam was released about 3 months ago at MSRP of 100$, it is now selling at ~50$ shipped."

 

Fact is, they just aren't suitable in the vast majority of security uses, for the MANY reasons outlined above.

 

Oh, and I would be really surprised if that camera has a 1/3" sensor. Frankly, I'd be surprised if it had a 1/4" sensor. Number of pixels is never representative of sensor size - just look at your average 8MP smartphone camera these days: my HTC does 720p video and it would take ten of its sensors to cover a 1/4" CCTV camera's sensor.

Camera : Microsoft LifeCam Studio

Sensor Type : CMOS Color (OmniVision OV2710)

Sensor Size / Pixel Size : 1/2.7" (3 x 3 µm)

Sensitivity : 3300 mV/(lux-sec)

Built with OmniVision's proprietary 3 μmOmniPixel3-HS™ high sensitivity pixel technology, the OV2710 delivers low-light sensitivity of 3300mV/lux-sec, S/N ratio of 39 dB, dark current of 10mV/sec and a peak dynamic range of 69 dB. This enables cameras to operate in virtually every lighting condition from bright daylight to nearly complete darkness below 15 lux.

Look at http://www.flickr.com/photos/sharpshutter/6667338191/

 

Vivotek are rather cheap for good 2mp camera, they still cost ~500- 900$

[Soundy 1]

You left a line out: "It is hard to find specs for the sensor inside the cameras -- this is supposedly for the MS studio HD"

 

Printed specs are nice, but largely meaningless on their own. Unscrupulous Chinese CCTV manufacturers have been relying on them for years, pushing cheap cameras as being more than they are... cameras that fall far short when put into actual use.

 

Since you seem to be missing the point, I'll say it again: if USB webcams worked so well as security cameras, you'd see them used a lot more.

 

But you don't... don't you think there's a good reason for this?

[pkoi 0]

You left a line out: "It is hard to find specs for the sensor inside the cameras -- this is supposedly for the MS studio HD"

 

Printed specs are nice, but largely meaningless on their own. Unscrupulous Chinese CCTV manufacturers have been relying on them for years, pushing cheap cameras as being more than they are... cameras that fall far short when put into actual use.

 

Since you seem to be missing the point, I'll say it again: if USB webcams worked so well as security cameras, you'd see them used a lot more.

 

But you don't... don't you think there's a good reason for this?

OmniVision make sensor for high end IP camera, I little doubt their printed specs.

 

Lets say for a moment the sensor is not that bad.

 

Start at 30$

Swap the USB controler for an Ethernet one, remove high quality microphone, remove audio processing chip, remove auto-focus mechanism.

You are left with 470$ to find a slightly improved sensor, h.264 chip (15$?) a custom metal box and a dozen IR LEDs.

 

I wouldn't be surprised if BOM for good IP cameras was about 15% the cost they sell them for. <-- This is the point I was trying to make.

[buellwinkle 0]

First understand that BlueIris is sort of CPU hog. You start adding a bunch of HD cameras, you'll need a serious PC to run it on. USB camera rely on the PC's CPU to do the work that IP cameras do internally, so it will also eat up CPU. a good amount. So while it may work on paper, you may want to try it and check the CPU utlization. Like other's have said you are limited to the USB limitations in terms of bandwidth and cable length. While one 1080P camera won't saturate the USB port, you may not realize that USB ports are shared, so you may overload the USB bus if you add a couple of these at the same time. Yes, I know it's rated 480Mbps, but that's bits (small B), 1080P no compression may use a good portion of that. probably about 1/5th. Also, check to see if the driver will support multiple cams. Never seen more than one webcam on a computer.

[pkoi 0]

. While one 1080P camera won't saturate the USB port, you may not realize that USB ports are shared, so you may overload the USB bus if you add a couple of these at the same time. Yes, I know it's rated 480Mbps, but that's bits (small B), 1080P no compression may use a good portion of that. probably about 1/5th. Also, check to see if the driver will support multiple cams. Never seen more than one webcam on a computer.

You can plug as many webcam as you want, unless there are driver conflict, (not gonna happen with Logitech / Msft)

 

UBS2's 480mbps is much less than what is needed for uncompressed 1080p ,

It is even more bandwidth than what most hard-drive can write at, (125mb/s or 1 gigabit/s)

 

Given the Logitech c920 has h264 compression in the camera , I think you could run ~8 of them on a shared 480mbps. And adding a 10$ USB2 - PCI addon card is adding another 480mpbs.

[buellwinkle 0]

While h.264 compression helps with bandwidth, the decompression that the PC has to do to feed BlueIris will suck up even more CPU. Like I said, try it and see. Just providing things to look for, breaking points that may happen when you approach the limits. Also, what do the USB extender's cost, maybe more than the USB cam costs. Nice thing is you can go to Walmart, Costco or Best Buy, get what you need, try it and return it if it doesn't work out.

 

May be a great idea, not sure many have tried it.

[thewireguys 3]

I would love to see some images from your USB cameras in real world conditions. Low light and bright back lighting would be nice to see.

[pkoi 0]

I would love to see some images from your USB cameras in real world conditions. Low light and bright back lighting would be nice to see.

What do you mean by "bright back lighting" ? What would that achieve ?

[Soundy 1]

Bright back lighting is a common problem that real security cameras have to deal with on a daily basis, and your $50 webcam will fail miserably at.

[pkoi 0]

Bright back lighting is a common problem that real security cameras have to deal with on a daily basis, and your $50 webcam will fail miserably at.

The back of what ? I'm asking.

 

Nevermind, I'll setup a test ... Aint that a software + dynamic range issue ?

 

I don't have much time right now, but this is what I have for now.

 

http://dl.dropbox.com/u/2479243/2012-04-09%2023-45-24.973.wmv

I don't have a pole light in front of my house and have big trees so the lightning at the end is almost pitch black.

 

I could not record 1080p since I was running it on a kind of netbook which like to downclock to 800mhz when off AC.

 

I though I had broken the webcam firmware since it seemed it was stuck on B/W on a new PC. Apparently the settings are saved in the camera itself, (it was on lowest color saturation)

[Soundy 1]

Backlighting, as in... a person coming into a dimly-lit store, through a door with bright sunlight outside. If a retail outlet has cameras, chances are that they probably have one facing the door with the intent of capturing facial details. Most cameras will dim their picture due to the overall bright lighting of the scene, and your subject becomes little more than a silhouette.

[buellwinkle 0]

Sensor's ability to distinguish colors drops off as the amount of light hits it diminishes, normal for any camera, but usually a survellience camera will switch to b&w to gain a litte better low light capability but not always for the better.

 

A webcam has an IR cut filter that is permanently in place. This is to correctly colors caused by infrared lightwaves that sensors are sensitive too, this makes things like trees green, your black bowtie black. The downside is that the webcam will not work with IR lighting, so you'll need regular white light to light up the area for security purposes. Do you need it work at night, and if so, have you given that any thought? Landscape lighting that focuses on lighting up plants and hardscape will look great on the webcam, but not really shine a light on the subject you may be trying to capture. Just something to consider.

 

I love the experiment, look forward to seeing the results.

[pkoi 0]

Sensor's ability to distinguish colors drops off as the amount of light hits it diminishes, normal for any camera, but usually a survellience camera will switch to b&w to gain a litte better low light capability but not always for the better.

 

A webcam has an IR cut filter that is permanently in place. This is to correctly colors caused by infrared lightwaves that sensors are sensitive too, this makes things like trees green, your black bowtie black. The downside is that the webcam will not work with IR lighting, so you'll need regular white light to light up the area for security purposes. Do you need it work at night, and if so, have you given that any thought? Landscape lighting that focuses on lighting up plants and hardscape will look great on the webcam, but not really shine a light on the subject you may be trying to capture. Just something to consider.

 

I love the experiment, look forward to seeing the results.

 

What did I just read ? If you're explaining all that because you noticed it was B/W note that I explained why in my post.

(it was on lowest color saturation)

As someone who has removed the IR filter from his Canon 20D, I kinda know what you're talking about.

[buellwinkle 0]

Just curious, why did you remove the IR filter from your Canon 20D? Why did you just not install a switchable IR filter so you can turn it on/off electronically like a surveillance camera?

[MaxIcon 0]

Did you ever find the f-stop numbers on any of the webcam optics? I've searched some, but haven't come up with anything. This is a fairly important number for those of us who do low-light monitoring.

 

So, let's look at the numbers. 1080p is 1920x1080 pixels. At 3um/pixel, that gives sensor dimensions of 0.227" x 0.128", which gives a diagonal of 0.26". Maybe there's a border on each pixel and it takes it up to 0.33"? Hard to say without more detailed data.

 

Next, the S/N ratio of 39 dB isn't up to what you get from analog or digital cctv sensors, which are typically in the 60 dB range, give or take a few dB. This spec is what will make a difference between really noisy performance and less noisy low-light performance. Even expensive IP cams struggle with this, due to the small element size.

 

Finally, the blurb says it operates "...to nearly complete darkness below 15 lux." This isn't a very low lux rating for CCTV gear. Many manufacturers exaggerate this number, but it's rare to find one that doesn't go below 3-4 lux for white light.

 

I'm not sure why the hardware specs are so hard to find for these, but this may be part of the reason.

 

IP cams are a pretty competitive business. If someone could make a useful 1080P IP cam for under $100, I believe they would. Certainly, people like Foscam push the lower price envelope aggressively, but everyone who tries them knows the tradeoffs of cheap gear.

 

Heck, Logitech makes inexpensive VGA IP cams, and I don't think they offer them in 1080p or even 720p - who better to exploit these inexpensive webcam sensors?

[pkoi 0]

I think using a webcam as a security camera for protecting the DVR PC area is much more cost efficient, As long as you don't spend to much time setting the software, (rarely the same as Analog software) I would personally use iSpy (free) or i-Catcher (costly).

 

Soundy was right, in that USB 2 over UTP was costly. USB 1.1 are dirt cheap though, (8$)

At the very worst one could use a cheap PC as as USB HUB, as long as it has a GB Ethernet it should be fine sending over ~6 webcams.

 

I would also imagine a setup where there is already 10+ workstations, Having to watch employes over this kind of system would be very cost efficient.

 

USB over IP

http://sourceforge.net/projects/usbip/develop

 

a thread on webcam on USB 1.0 over Cat 5

http://www.wxforum.net/index.php?topic=9782.0