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WebCam Options for Linux?
Doesn't_Comment_Code asks: "I am working on a motion capture system, and I plan to implement it with several webcams viewing the same space from different angles. I have looked into some webcams and drivers for Linux, but I'm not sure which are best. Specifically, I need to connect three, four, or five cameras to a single machine. Can any current Linux drivers accommodate this? Also, I'm looking for basic, no-frills cameras, as automatic gain control and other features may amplify dark parts of the image that I need to stay dark."
http://www.qbik.ch/usb/devices/showdevcat.php?id=9
You'll probably find this page/list useful as a starting point
- Gef
Google sez: The Philips driver has multiple camera support.
Remember you'll have to choose the camera based on the 'chipset', not the brand name.
"I assumed blithely that there were no elves out there in the darkness"
http://www.fhttpd.org/pub/qcwebcam/README.html
Can be easily modified to use v4l
Contrary to the popular belief, there indeed is no God.
I have a Creative Video Webcam Plus, its USB, uses the ov511 driver, and according to the module info, can support multiple cameras, and you can apparently turn off the auto brightness stuff, but I've not tried it. Why not modinfo a bunch of webcam modules? :)
Dirk stood in the Stanley
I use a brooktree card, and in the past I've used the parallel port to switch between 6 different cameras on a single composite input, managing one scan every ten seconds on my P200.
However, there are many different cards based on the bt878 chipset which support two or more inputs and if I was mad enough to do it all again I would probably use two or three such cards in a dedicated (and slightly faster, perhaps 400MHz) camera server, and scan them using motion That should give me up to 9 cameras scanned at two or three frames per second.
455fe10422ca29c4933f95052b792ab2
The Philips Webcam driver above warns that the bandwidth of USB may not be enough for more than 5 cameras.
Now, The Philips is a USB 1 device, but USB 2 has MUCH more bandwidth than 1. Try sticking an external CDROM into a USB 1 port one day and you will see what I mean.
So a USB 2.0 camera would probably be better, but I do not know if there is any such thing. A USB 2.0 PCI card is quite cheap though, although on my Suse 8.2 box the !"! machine does not boot completely if there is nothing stuck into the USB card!
The dangers of excessive individualism are nothing compared to the oppressiveness of excessive collectivism
I'm not being pedantic, just informative
"I assumed blithely that there were no elves out there in the darkness"
Slashdot really isn't the best place to ask a question like this. I would recomend the Video4Linux mailing list. You can subscribe at https://www.redhat.com/mailman/listinfo/video4linu x-list or you can find their web site at http://bytesex.org/v4l/ , subscribe to their mailing list at https://listman.redhat.com/mailman/listinfo/video4 linux-list or look at the (searchable) archives at http://marc.theaimsgroup.com/?l=linux-video&r=1&w= 2 .
Slashdot really isn't the best place to ask a question like this. I would recomend the Video4Linux mailing list. You can subscribe at https://www.redhat.com/mailman/listinfo/video4linu x-list or you can find their web site at http://bytesex.org/v4l/ , or look at the (searchable) archives at http://marc.theaimsgroup.com/?l=linux-video&r=1&w= 2
I have a Logitech QuickCam Web, there are only working kernel modules for 2.4 though (no 2.6 experimental goodness) - you can grab 'em from the sourceforge page. I don't know if you can have multiple cams though.
Just to be sure if a specific driver is multi-device capable ask the developer if it's not specified on the website.
I suggest you go find the cheapest three webcams, look them up in the USB devices database if they work with Linux, and then use motion to get the images.
--
Du Deutsch -> Du gehe Symlink
D-Link has some nice units that are OS independant.
Can You Say Linux? I Knew That You Could.
Go buy an iSight at your local Apple store. Just plug it into your FireWire port and you're done. Piece o' cake.
What's that? You don't have a Mac? Oh, you poor DEAR!
I've got 2 se401 webcams hooked up through USB on Linux, they go to /dev/video1 and /dev/video2 or something. Much better than I was able to pull off in Windows. I'd imagine 3 webcams would be a piece of cake as well.
Video for Linux (v4l) (much info here or the newer v4l2 are the places you want to check out as those above have men tioned. Also, check out this site for some code to used as a starting point. Attaching multiple cameras is no problem as the different USB cameras just map to /dev/video0, /dev/video1,...
Like pi? Try 10,000 digits.
is a Xirlink. I wasn't sure which camera I could use either a few weeks ago, so I figured I should just look in the kernel to see what was supported. I enabled V4L support in the kernel, and then looked around in the USB section and found the Xirlink driver (among others). I got the xirlink cuz it was 9.99 ;) Even with 7 bucks shipping it still came out cheaper than any of the other cameras I could find. Works great too, though I've only really used it with gnomemeeting.
Chaos is Divine *
If you're talking USB(1), then even a single "webcam" is useless for motion-capture unless you're talking about using really low resolutions. USB is just too darned slow.
As another person stated above, get some capture cards with BrookTree chips. The Bt848 and Bt878 are very well supported in Linux, and have been for many years (used to use one on a 486).
The cards can be had around $50-$75 usually, sometimes as cheap as $20-$25 at local computer shows.
According to the docs for the bttv driver, the PCI bus doesn't get saturated with 4 cards, so this is probably the way to go.
Another plus is the fact that not only are these capable of much higher resolution than any USB camera out there, the signals you can pipe into these cards can be much higher quality and from a variety of sources (old camcorder, mail-order pinhole camera, DVD-player via S-video, etc.).
In other words, you can use a high-quality CCD rather than a low-res/low-quality/low-light-sensitivity CMOS imager (that nearly all USB "webcams" have).
Another possible option is ieee1394 ("firewire") cameras.
Anyone know if any firewire webcams (not camcorders) are supported in Linux? (I've only seen two brands, years ago)
BTW: I have an IBM and a Labtec USB webcam. While both work with Linux, both suck horribly in every category compared to my Sun Camera connected to my Bt878 card (which also contains TV and FM tuners).
- Preferences: Solaris 10 (servers), Ubuntu (desktops), Solaris 11 (personal servers) -
Grandparent is correct. The "magic" in this is called compression. The chipsets actually use compression in sending the stream to allow for higher framerates at these resolutions.
That said, I still think that a capture card is the best bet because it allows you to change the camera at a later time without worying about breaking your Linux support
Like pi? Try 10,000 digits.
I've done something similar using black and white video cameras as I needed really good low-light capability. My solution ended up using Philips+Nogatech based video capture-to-USB dongles and Video 4 Linux drivers.
As someone else mentioned, forget it if you want motion. In that case, PCI/1394 is the only way to go.
First, collect the best information. That means a good camera and exact positioning. If you don't use a good camera, you won't get good edges. If you don't position it accurately, your edges won't end up in the right place. So I expect that webcam housings will be just too difficult to work with. ALSO, usb cables the length you will have to use are dodgy. All you are interested in is the luma channel, don't worry about colors. Maybe you ought to use super vhs cam output and capture only luma with several dedicated cards. As you know, the svhs cable carries luma separately. Also,, if you use this setup, you can vary the compression. If you use a DV setup, you are stuck with 3:1
Your project sounds awesome.
Any preoccupation with ideas of what is right or wrong in conduct shows an arrested intellectual development. (Wilde)
I am working on a video conferencing sytem so I can pick up chicks, and I plan to implement it with several webcams viewing my naked body from different angles. I have looked into some webcams and drivers for Linux, but I'm not sure which are best. Specifically, I need to connect three, four, or five cameras to a single machine. Can any current Linux drivers accommodate this? Also, I'm looking for basic, no-frills cameras, as automatic gain control and other features may amplify dark parts of the image that I need to stay dark, like the area around my crotch so the girls don't laugh.
I am putting together a security system for a client of mine. Wanted something reliable with software for a decent price.
http://www.linuxmedialabs.com/
Check out the LMLBT4M card (listed under all products) 4 channel multiplexed or the LMLBT44 with 4 channel full-rate.
They have free software with motion capture.
I could tolerate 10 frames per second and 160x120 pixels, but I can't tolerate the motion blur. I want to do stereo vision, so I want all the cameras to capture an image at the same time.
What's the cheapest USB or firewire camera which allows control of the exposure time and timing?
My computer has USB 1.1, 2.0 and firewire ports on the motherboard. I don't want to use a PCI card, because I don't want anything that can shake loose.
I played with the QuickCam Express, it's cheap, it works as long as nothing moves. Not good for my robot. I want to put cameras facing in all directions, rather than handle the complexity of tilt and pan.