Suggested Starting Point

On 04 Jul, in article <871wt159ha.fsf@localhost.localdomain>
     no@spam.thankyou "Ian Braithwaite" wrote:

>paul$@pcserviceselectronics.co.uk (Paul Carpenter) writes:
>>      no@spam.thankyou "Ian Braithwaite" wrote:
>>
>> >I'd have thought USB 1.1 was fine for a webcam.
>> 
>> I would have thought, by looking at earlier post in the thread, that
>> mentions some figures, it should become clear. USB1/1.1 has a CLOCK
>> rate of approx 12MHz, so you might be lucky and get 2 frames a second
>> (depending on size of image and if camera has compression).
>
>I've seen the Philips 740/840 webcam used with Linux on some mobile robot
>projects with great success.
>With USB1 it manages 5fps at 320x240 uncompressed (that comes to 4.6Mb/s
>data) and 30fps, or 640x480 at 15fps, with the camera's built in compression.

Which exactly echos my point above stated again below

   (depending on size of image and if camera has compression).

In my books 320 x 240 is toy vision (and usually very grainy on most cameras)
640 x 480 (as raw size) is the smallest frame size I even consider.

The original poster was trying to achieve 30fps and preferably 640x480.

>(http://www.lavrsen.dk/twiki/bin/view/PWC/ApplicationProgrammingInterface
> has the full table.)

Lots of talk of software and cameras, and nothing about minimum hardware
requirements, considering original question this is important.

>So it might not be quite as hopeless as you seem to think.
>It depends on the application.

Considering original request and expected SBC size and hence power/resources
I think my answer was nearer the mark.

-- 
Paul Carpenter          | paul@pcserviceselectronics.co.uk
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