-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I have yet to find a good website talking about security cameras and Linux (the hardware side that is). There are lots of software packages and various odds and ends that work with v4l such as frame grabbers, etc.
I recently bought a Logitech QuickCam Pro 4000 (USB) which is a nice enough camera that is crippled under Linux because Phillips won't release their proprietary compression algorithm. It will still give 640x480 resolution but NOT the full 1280x960 that it says on the box. It seems hard to believe that they really have a cutting edge compression algorithm that is genuinely valuable, more likely it is just a matter of corporate disregard of Open Source and/or they have infringed someone's software patent somewhere and don't want the infringement to become public information. The other possibility is that the camera does NOT actually do any more than 640x480 but the additional resolution is done by software interpolation (like many scanners advertise a high "BS" resolution then a lower "optical" resolution, aka the real resolution). I do notice that the Logitech website says that the full resolution is only available for still pictures and on some other cameras it does mention software interpolation. Needless to say, it would be good to avoid buying the Logitech unless you want a crippled camera, but now the question comes up about what DO you buy? In the shops, there are no other USB cameras going anywhere near 1280x960 resolution in full colour. I can't understand why because USB2 has plenty of bandwidth and is hardly rocket science these days but yet most of the cameras are around the 320x240 mark. Another option is to go for a PAL capture card and a brooktree chip. That works OK with a regular video security camera but the resolution of regular video is still not much different from 640x480 so you really aren't much better off. Most of the PAL cameras are from 450 up to 500 lines resolution and I would presume that the horizontal sampling must be limited to something of the same order of magnitude (even though analog cameras don't really have a horizontal resolution, there is a limit to how much real detail is in the scan). I've also looked at a few IP cameras and they cost a heap extra for very little return (well, you can have longer cables than with USB so that is one useful thing). They also have low resolution. For example, a D-Link wireless camera selling for $500 is here: http://www.dlink.com.au/products/multimedia/dcs2100+/ Which has soooo many features -- except for a decent picture, when you finally scroll down to the bottom of the specifications it has only 320x240 resolution (which is squint quality). So is the Logitech 4000 running in crippled mode considered the best that you can get for a sane price? Is the crippled mode really the best it can do in honest optical resolution anyhow? I bought the logitech for $135 and probably would be willing to go to $200 if I was getting something noticably better. - Tel -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.6 (GNU/Linux) iQIVAwUBQt4ca8fOVl0KFTApAQIC9g/8CrnacOq//xT07hriIkEBZwPJtBgVpgO6 hdZWMxmaa1myDFjDSuu5dB+j3PIPR9uXfJQjD+Ih7p4enQwvlhZQYR67waQrEWnc xPDgv3nAkrjp5JgnsYeXiM8E2IOuF02YDZn2L4EyKo4ItCtYBoFiY8eO2Y5HzNpZ F41CT/IFqGdHnXY8pnp02jcvsAWHxjgAW8+X8BzpZ+R2kqUHJPIU7zkh1/us4l1A m0pAM3Kx+a8TudkVHstI99tGYWMFxqscvYENtXyvKdQqhTbbKoc5iOyNtjwqN7Z+ BuynH8w3RCLxmsCmE7kAGFRWtBtJDyV76yf9chEYVMOOAXiIwFPG9dslU5nAqg3o GFhHj2qiRb83ir8l2jYYuPQCzdWprm7wEarJ1gc9Pn0d3wfZu9+i48B/CY9Co8Cm w7V74rCGPRqF3krOf4Nwi5+WB64qxq6ppJ5HweJ869x3IwbusdUyFaR/sV80uRJX xCXvyxem6/bqRxKTfJhD8Xy0sdiOURerrCz1zU9utHmyJY7ftpI/HJycW1CN5kGP WeFhTJ65Bgx/pTDY6q5Tk2VX/WPUO5uf8wOa2cT+uoka/rgLu3Soiaqnqf0dY0fp CYhhNaXXVYbDIxrd9mNsy6Xxe8gbxuQkmqYdMOPbNpwyGeMdmxEwLlGXsyxqLYPJ VHsvq2fWOFI= =pa7T -----END PGP SIGNATURE----- -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html