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Hardware Hacking Toys Science

Infrared Webcam HOWTO 238

Posted by Hemos from the the-fun-of-hacking dept.
Geoff Johnson writes "Some of the Slashdot readers may be interested in this page I put together. It describes how to make an ordinary webcam see in the near infrared waveband."
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Infrared Webcam HOWTO More

Infrared Webcam HOWTO

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  • duh (Score:5, Insightful)

    by oliverthered ( 187439 ) <oliverthered@hot ... om minus painter> on Sunday March 13, 2005 @10:12AM (#11925953) Journal
    Let me guess, remove the IR filter from in-front of the lens.

    • Re:duh (Score:5, Informative)

      by m50d ( 797211 ) on Sunday March 13, 2005 @10:16AM (#11925975) Homepage Journal
      Well, and replace it with one to block visible light. But yes, that's about it.

      • Re:duh (Score:5, Informative)

        by oliverthered ( 187439 ) <oliverthered@hot ... om minus painter> on Sunday March 13, 2005 @10:23AM (#11926013) Journal
        You don't need to for 'night vision', which is what I expect most people will be interested in.
        Full colour (maybe a tiny bit washed out because of the extra IR) during daylight, and at night switch on the IR light and you've got an IR camera.

        Near IR isn't that interesting, except humans cant see it, what would be cool is if the chips could pickup far IR so you could see heat.

        • Re:duh (Score:5, Interesting)

          by budgenator ( 254554 ) on Sunday March 13, 2005 @11:06AM (#11926201) Journal
          Cadillac has an interesting thermal system, I haven't really dug into it in depth, but basicaly the sensor is a bunch of capacitors similar to a ccd sensor. When the IR image is focased on the sensor, the heat causes the diaelectric between the capacitor plates to warm up and expand changing the charge on the capacitor and make it readable.

          Sooner or later someone is going to hack the system for some serious geek factor. I could see someone hackering several of these different systems together for some cool false-color IR video. I used to do quite a bit of IR photography used Kodak's IR false-color slide film, green showed up as blue, red was green and IR was red if memory serves me correctly. The biggest problem was the film used the old-fassioned E4 process, so you either had to send it to Kodak or do it your self

          • Re:duh (Score:5, Informative)

            by huge colin ( 528073 ) on Sunday March 13, 2005 @12:04PM (#11926457) Journal
            Cadillac's system was actually a Barium Strontium Titanate (BST) module, developed by Raytheon. It required a thermal differential in the scene from frame-to-frame to be able to see anything, and thus a "chopper" wheel (a rotating slotted disc) had to run in front of the detector. The picture would smear and was generally low-quality. The module used by Cadillac was also rather low resolution (160x120, I believe).

            The alternative to BST is microbolometer technology, developed by Lockheed Martin / BAE Systems and others. A microbolometer array consists of vanadium-oxide bridges that vary their resistance when exposed to thermal radiation. The scene will occasionally need to be "shuttered" (i.e., zero all the pixels against the back of a shutter mechanism to cancel the thermal drift that creeps in over time.)

            Unlike light-amp, true thermal imaging allows you to see in complete darkness. And unlike projected-IR, it isn't limited in range by any kind of IR-transmitter. And unlike either of those technologies, it allows you to very quickly find humans (or other mammals) in a scene, and it allows you to see where things used to be by the heat-shadow that they've left.
          • Couldn't you use normal film, then develop in warm developer (say 35 degrees C) and use chemical swelling to change the color? That would shift the frequency down.
            No idea if that works with normal film or not..

            • Re:duh (Score:3, Informative)

              by budgenator ( 254554 )
              basicaly the E4 process you expose the film
              1. develope it the reduce the exposed silver halide crystals to metalic silver( results in an negative image)
              2. bleach out the exposed silver( removes the negative image)
              3. remove the film and expose it to light which exposes the undeveloped silver halide crystals
              4. re-develope the film to reduce the exposed remaining silver halide crystals to metalic silver resulting in an positive image
              5. fix the film to remove any undevelopes silver halide crystals
              6. the silver reacts w
              • False color means ... what you 'think' red is is represented by something... what you think 'green' is is something... and what you think blue is is something else.

                False Color means applying a dye that is proportional to exposure and it may or may not represent reality. Since we have 3 sensitivities (Excluding night vision) we have three discreet channels for image processing at the same time.

                Biggest problem: When Green Grass comes out White because it is IR reflective. Thats when analysts have a fit :
      • Took the whole camera apart, removed the optical pass filter from the CMOS chip, replaced it with an IR-PASS filter (rejects lessthan 750nm)... and I have a visible focus / IR sensitive camera.

        Great shots, too

        1st test shot here: http://www.deviantart.com/deviation/12473546/ [deviantart.com]

  • Oh, great. (Score:2, Funny)

    by millennial ( 830897 )
    Now Paris Hilton's new sex tapes will be done by webcam... meaning even worse video quality! Seriously, though, that's pretty sweet. Props to this guy for figuring out how to do it.

    • Re:Oh, great. (Score:3, Insightful)

      by Xyrus ( 755017 )
      This isn't really anything new. Amateur astronomers have been doing this with webcams for awhile now. Even in the near IR range, some things look a little different.

      Not recommended when planet imaging.

      ~X~

  • Can it see through clothing? (Score:5, Funny)

    by Anonymous Coward on Sunday March 13, 2005 @10:13AM (#11925958)
    Cause I'd really like to take my PC to the beach and get webcam shots of da honey's.

  • infrared wecam! (Score:5, Funny)

    by Anonymous Coward on Sunday March 13, 2005 @10:15AM (#11925966)
    that's just fantatic!

  • Night Vision Linux Webcams All the Rage? (Score:4, Interesting)

    by filmmaker ( 850359 ) * on Sunday March 13, 2005 @10:17AM (#11925982) Homepage
    Infared web cam? Somehow I don't think Bubble Cam [andieandmike.org] would be quite the same at night. :D

    I do wonder what the most common applications for Linux/IrDA are, considering the trend I've observed where among the most commonly requested Linux HOWTOs [joeldalley.com] recently have been 'laptop', 'infrared' and 'webcam'. Is everyone building infrared webcams?
    • I do wonder what the most common applications for Linux/IrDA are, considering the trend I've observed where among the most commonly requested Linux HOWTOs recently have been 'laptop', 'infrared' and 'webcam'. Is everyone building infrared webcams?

      Maybe you're confused here, and should check out some of those HOWTO's yourself (and read the article for once), to see what it is all about?

      To use a webcam for looking in the infrared spectrum, is not the same as using infrared light for shortrange communicati

  • The WEcam... (Score:4, Interesting)

    by mindriot ( 96208 ) on Sunday March 13, 2005 @10:20AM (#11925998)
    ...and, soon to come, the THEMcam!

    SCNR... sometimes I'm amazed at what kinds of typos make it through to the frontpage.

    But besides that, very nice article. I personally found IR very useful for some surveillance-type situations. A few years ago, my father set up an IR-sensitive camera and an IR diode in a birdhouse in our garden, which allowed us to watch the new-born ones without creating any disturbance.

  • Burgler Cam?? (Score:5, Interesting)

    by GreyPoopon ( 411036 ) <gpoopon@gm[ ].com ['ail' in gap]> on Sunday March 13, 2005 @10:26AM (#11926023)
    Does anybody think that coupled with a pure IR source of light this item would be useful in catching would-be prowlers without alerting them? OK, probably a stupid idea...
    • With a non-alerting burglar cam, you get a picture of the guy who stole your TV, your jewelry, your laptop, ...

      With an alerting burglar cam/alarm. The guy sees that he's been spotted, freaks out, and leaves. You keep your stuff.

      I guess your choice depends on your priorities.

      • Re:Burgler Cam?? (Score:4, Insightful)

        by shic ( 309152 ) on Sunday March 13, 2005 @11:55AM (#11926407)
        There is a lot more to the idea of video security than the simple "alerting" or "non-alerting" you suggest.

        For example, using your example of a car - I'd consider myself a madman if I opted not only to have a car alarm - but also to make it as obvious as possible that I am equipped with one. The snag, however with alerting alarms is that after a few "false alarms" it is widely understood that alarms signals will be ignored - people assume it is a technical fault... and the criminals know this too. Another problem with the alerting alarm is in automatically deciding at what point to take issue with someone's actions. For example, I'm aware of areas in which organised youths check all the car doors in a neighbourhood - hoping someone has forgotten to lock and alarm their car. Under these circumstances an alarm system does no good... It is important to discriminate... Burglar alarms also offer no protection from vandals - whereas a CCTV with night vision may well do - if only by identifying weaknesses in manned security. I imagine an infra-red video surveillance system would be an extremely good way to improve security for applications such as monitoring business car parks; monitoring entranceways to identify where layabouts trespass before any real harm occurs - as well as providing some way to counter graffiti tagging and other illegal unpleasantness.

        I've long thought this would be a fun project - but as yet I've not found time to tinker.
        • The snag, however with alerting alarms is that after a few "false alarms" it is widely understood that alarms signals will be ignored - people assume it is a technical fault... and the criminals know this too.

          As illustrated in
          How to steal a million [imdb.com] movie... ;-)

          Paul B.
      • unless he/she gets pissed and just starts trashing your stuff....

        I know when you secure car stereo equipment frustrated theives end up cutting speakers and ruining wire runs.

    • Re:Burgler Cam?? (Score:2, Informative)

      by ebob ( 220513 ) *
      Not so stupid.

      A couple of months ago a guy in rural San Diego did exactly that and nabbed some identity thieves stealing folk's mail from their mailboxes at night. Here's the story from the San Diego Union Tribune:

      http://pqasb.pqarchiver.com/sandiego/ [pqarchiver.com]


    • Re:Burgler Cam?? (Score:3, Informative)

      by deacon ( 40533 )
      Sure. But if you want to step up in image quality and view range:

      Use this camera [supercircuits.com], illuminate with this device [supercircuits.com] and use a C-mount lens from this page [surplusshed.com] if you are comfortable with removing the electronic iris in some of these older, but superb qulity, lenses.

      You will be able to read a license plate at 75 feet in complete darkness.

  • 6.9Mb DivX AVI file (Score:2, Funny)

    by Anonymous Coward
    Sorry, man. Slashdotting in progress.

  • IR filter (Score:2, Interesting)

    by RikRat ( 834490 )
    Hmm, I opened my sweex webcam (the same he has) and unscrewed the lens. But my IR filter is round (so not a square as in his webcam) and won't come out.

  • Not all cheap webcams have filters. (Score:5, Informative)

    by OneDeeTenTee ( 780300 ) on Sunday March 13, 2005 @10:40AM (#11926073)
    If you're lucky the webcam won't have an IR blocking filter.

    You may want to check it with a remote (or just put your IR passing filter in front of it) before you take it apart.
    • I have a camcorder (analog, large by modern standards) which has a mode in which it takes infrared images. It has a bright infrared LED on the front, so it can work as an active infrared system in total darkness (it gives weird green-and-white images). The thing is, when it is in normal daylight mode it can still see IR, and you can see, as you say, remote controls as flashing lights. Which makes it's own remote control look silly when we use it to start/stop recording.
    • Yup, my Color QuickCam express didn't have a filter, so all I needed to do was insert the "Visible Color" filter on top of my lens and I have a IR QuickCam that is easy to "undo".
      • In fact it does at least mine, but its quite crappy (besides IR is a bitch to block perfectly, haven't seen a single filter that is able to kill to 100% of it, so you will see a remote even though your camera has one). On my QuickCam express it is located behind the rearmost lens i.e. the one located closest to the sensor (which it glued to the housing) so you have to (carefully) pry that one loose (i used a really small screwdriver and an awl), then remove the little clear square of glass behind it (lookin
    • Even if you see a remote it will most likely still have a filter. The LED from the remote is bright enough to go through any IR filter. However, if the LED appears a little bluish, you definitely have a filter.

  • Many high-end web-cams have day/night and pan/tilt (Score:2, Informative)

    by Anonymous Coward
    We've been buying VB-C50iR cameras from NuSpectra for construction monitoring. We can do all this--perhaps not as cheaply!

    Pan/tilt/zoom control, day night filter (changes to IR/Night mode on a schedule)... Plus 26x optical zoom rocks.

    NuSpectra has a demo camera out of their office in San Francisco.. See demo in upper right corner of page [nuspectra.com].

    We also use the SiteProxy software that lets us build time-lapse movies from all the camera's preset positions on the fly.

    Check em out!
  • Do you think his hair is transparent to IR, or the IR made his hair fall out?
    • What's really cool is looking at a person through a 3-5 Micro-Meter (aka "Far IR" thermal camera (think military and very expensive). Your hair looks black near the ends, and red near your scalp. Glasses appear black, veins are sometimes visible, and you can see 2 guys in a zodiac up to 20 miles away (which is why the military likes them so much).

      This webcam mod is pretty cool, but only for us normal folk without $40,000 to spend on a REAL thermal camera.

  • OK..... (Score:5, Funny)

    by mr_z_beeblebrox ( 591077 ) on Sunday March 13, 2005 @10:43AM (#11926092) Journal
    So the article details a cool hack, props. What I want to know is.....why was I able to download the 6.9 MB AVI file at the end. Isn't his server supposed to die or something? I can never download the files referenced by a /. link. Is something wrong?
  • altho, most that ive seen ahve the IR filter directly attached to the CCD.
    you would remove the CCD, then remove the 'piece of glass' from it.

    some cameras achieve this effect differently, I have not quite worked out how they work.
    For example, Sony camcorders that have 'nightshot'
    also have an IR filter, but I suspect its something different. the switch not only engages some IR illuminators, but does something in the lens block itself. (switches something in/out mechanically)
    I know that the IR filter at the CCD remains there, its in a fixed position.

    I am now curious and have to dissasemble a sony lens block to see :)

    I used to work on cameras, and I have removed the IR filters on cameras before for a bit of fun.

    if you can get enough IR leds going you can get it pretty well lit.
    Altho, the resolution is probably not going to be that great at a distance.

  • X-Ray Specs (Score:4, Funny)

    by lildogie ( 54998 ) on Sunday March 13, 2005 @11:02AM (#11926179)
    Wow, just like those funny glasses I bought from the ad in the comic book back in the 60's.

  • One question (Score:4, Funny)

    by gone.fishing ( 213219 ) on Sunday March 13, 2005 @11:29AM (#11926298) Journal
    Will this mod void the warranty?

    (it's funny, laugh)

  • Heat Seeker (Score:3, Funny)

    by Doc Ruby ( 173196 ) on Sunday March 13, 2005 @11:32AM (#11926313) Homepage Journal
    We need a demo of pix of his hot neighbor in her nightgown. Too a HW hacker never sees her that way around sunrise.

  • Look for heat loss? (Score:5, Interesting)

    by crow ( 16139 ) on Sunday March 13, 2005 @11:37AM (#11926338) Homepage Journal
    Will this capture the right range of infra red to detect heat? If so, then I could see using it with a laptop on a cold day to see where I need to improve the insulation on my house.
    • It cannot, because it would be blinded by its own temperature emissions.

      The type of camera you want has a cooled detector/sensor. The early versions used a vial you would fill with liquid nitrogen. High pressure argon allowed to expand into a cooling chamber was also used. Modern cameras use a peltier type cooler to chill the detector.

      About 10K new, several are listed on Ebay for much less.

  • trashed my kensington videocam (Score:4, Funny)

    by emptybody ( 12341 ) on Sunday March 13, 2005 @11:46AM (#11926377) Homepage Journal
    I unscrewed the lense end - the same way you fine tune the focus.

    it then proceeded to fall over due to the usb cable coming free in back.

    I now have a little stack of lenses that I need to figure out the proper way to orient.

    2 lenses - 2 ways = 8 combinations.
    a third lense further out = x2 more combinations.
    a fourth lense on the outsite = x2 more combinations.

    Total 32 possible ways to re-assemble this little bugger!! DAMN-YOU!!!!

    Worst of it is, the pink lense is a lense and not a flat glass filter. I cant use this cam :(

    Anyone have a blow-up of this cam -
    Kensington VideoCAM VGA PC Camera
    Model#67015
  • Like I just did, and spend a minute or two rewiring the IR LED..

    And then you can use the IR cam, with a constant IR source and see in the dark, presumably.

    But I'll have to wait another few hours to test that.
    • Somewhat to my amazement, this actually worked quite well despite my dramatic ineptness with electronics.

      Pictures are in this thread [sudhian.com].

      I'd post a pic of the setup.. But I'm ashamed of it. Sellotaping wires to a battery just isn't .. y'know.. valid somehow.

  • Disgruntled ISP customer? (Score:4, Funny)

    by The-Bus ( 138060 ) on Sunday March 13, 2005 @12:16PM (#11926514)
    This guy must just be mad at his ISP or whoever does his hosting.

    The ~7MB video file at the end of the page doesn't even have anything to do with IR video. It's like he wants us to take the server down.

    So do him a favor and just download it 8 times.

  • If you want a time-lapse capture app for free... (Score:4, Interesting)

    by maird ( 699535 ) on Sunday March 13, 2005 @12:21PM (#11926531) Homepage

    ...Get one here: http://www.mair-family.org/Downloads/ [mair-family.org] Geoff says the software he had isn't very good. I couldn't find anything I was prepared to pay for so I wrote my own and publish it at that link. Sorry Windows only and WMV output. You can read the feature list for yourself but, in terms of Geoff's difficulty, it will capture frames at between 4s and one hour per-frame (configurable) and create a 15fps WMV.

    Go ahead, /. my web server...Hopefully my ISP is tolerant.

  • See through clothes! (Score:3, Insightful)

    by SiliconEntity ( 448450 ) * on Sunday March 13, 2005 @12:26PM (#11926557)
    We all know the real point of this - to let you see [kaya-optics.com] through [x-raycameras.com] clothes [impactlab.com] like the infrared video cameras that came out a few years ago.

  • See through camera (Score:2, Informative)

    by MaxBlue ( 538700 )
    Didn't Sony have an issue a few years back with their digital camera's seeing through bathing suits? Wasn't it have something to do with IR?

    Was their fix to add IR filters?
  • ...a stero camera hack that used VI and near IR -- then you could write a driver to output funky composite, layered image formats like the remote sensing applications use in GIS...

    or maybe I like image formats to much.

  • alternative approach (Score:5, Funny)

    by tverbeek ( 457094 ) on Sunday March 13, 2005 @12:47PM (#11926681) Homepage
    Or just accelerate your webcam enough (toward the object you wish to photograph) to blue-shift the infra-red into the visible frequencies. Put it on a really-high-speed ferris wheel or merry-go-round and synchronise the snapshots to its rotation if you want to keep it "stationary". Compensating for the doppler shift in the signal from the camera is left as an exercise for the reader. But no disassembly or modification of the camera needed!
    • the "blue shift" is the "doppler" shift you speak of... They call it blue shift and red shift but it is the equivilent of the doppler shift of sound waves.
  • I knew about this, now you all know about this and it makes me feel far less self satisfied and clever now that it's common knowledge.

  • Warning: state of USB webcams on linux (Score:3, Informative)

    by jago25_98 ( 566531 ) <slashdot.phonic@pw> on Sunday March 13, 2005 @01:07PM (#11926775) Homepage Journal
    I bought a sweex webcam like the one in the guide.

    Indeed the usb chipset is supported (sn9c103), but the sensor isn't. So I'm sending it off to Italy for Luca the developer, well it's no use to me.

    USB webcams can have different sensors within the exact same model, so you never really know when buying one whether it will work for sure.

    Hopefully this will change if the USB video standard (similar to firewire video standard), comes about.

    In the mean-time think about firewire cameras.
  • £20 all inc. to UK address and of course, working with linux!
  • Hardest part was putting the Logitech QuickCam back together the right way -- because which ever way which part was was quickly forgotten in the process. I didn't have any film handy but the cam now shows security marks on 50 Euro bill quite nicely. The picture is more of black and whitish without the filter. It sees through things.

    Now just good lighting. I have a bicycle led-light with individual lences for each led. One of these with proper leds might work nicely as home surveillance system.

    But sure was

  • This is great (Score:2, Interesting)

    by eanmeyer ( 867407 )
    Five minutes after I read this I dug out my old IBM PC webcam and started tearing it apart. Five minutes later I had a working IR webcam. Now I want an IR flashlight.

  • Tomorrow on Slashdot... (Score:3, Funny)

    by servoled ( 174239 ) on Sunday March 13, 2005 @02:15PM (#11927171)
    Tomorrow on Slashdot, how to turn an ordinary car into a convertible by removing the roof.
  • Gee, I wonder what the average slashdotter is going to use this for [kaya-optics.com]. (link probably not work-safe)
  • I pointed my TV remote at my Logitech webcam and it detected the IR light.

    Did the same thing to a Kodak CX6300 and a CX7300; they detected it.

    All I need to do is filter the visible light, no screwing around...or unscrewing.
  • Does anyone know of any consumer-level thermography [wikipedia.org] DV cams? Something like a regular DV cam with audio that you can plug into a Mac or PC through firewire and do standard video editing with. I came across this [indigosystems.com] on the net, but apparently the infra-red attachment [indigosystems.com] costs around 14 thousand dollars (US). I was hoping there was a much cheaper one out there for hobbyists who are interested in the aesthetic quality of the images [ir55.com].
  • Nifty, but videocameras would be much more interesting. I had an older model JVC that picked up the flashing IR of a TV remote...hmmm.

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