Read info from webcam video [message #181850] |
Thu, 20 June 2013 09:35  |
Sarah
Messages: 30 Registered: December 2010
Karma: 0
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I've a video Wi-Fi Cam.
In the room there is a small light that can be flashing.
Is there a way for read image using PHP pages and know is this light is flashing or not?
Thanks
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Re: Read info from webcam video [message #181886 is a reply to message #181882] |
Thu, 20 June 2013 23:44   |
Jerry Stuckle
Messages: 2598 Registered: September 2010
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Senior Member |
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On 6/20/2013 7:14 PM, Norman Peelman wrote:
> On 06/20/2013 09:23 AM, The Natural Philosopher wrote:
>> On 20/06/13 10:35, dandi(dot)box(at)gmail(dot)com wrote:
>>> I've a video Wi-Fi Cam.
>>>
>>> In the room there is a small light that can be flashing.
>>>
>>> Is there a way for read image using PHP pages and know is this light
>>> is flashing or not?
>>>
>>> Thanks
>> sure,. But an ardinio boards and profram it to sense the voltage across
>> te LED by attaching it to the camera, and send the result down a USB
>> portto a computer running linux, and then write a daemon on C to monitor
>> that and place the state in a temporary file or somewhere where PHP can
>> see it.
>>
>
>
> Ummm, really?!
>
>
>> Though quite why PHP is involved, its hard to say.
>>
>
> As long as he can grab the images from the cam via php (requires that
> the IP camera has an internal server) then it is quite easily done. As
> Jerry's response dictates. Examine the images looking for the tell-tale
> LED.
>
Actually it doesn't require a server on the camera - just an IP stream
he can connect to. Most IP cameras don't contain a server - they just
spit out packets. Of course, PTZ (Pan-Tilt-Zoom) cameras also accept
data from a controller, but again that's typically a stream (of which
there are several non-compatible formats).
Others can accept commands to do things like detect motion in various
zones on the camera (again a camera-specific command format) and similar
functions.
--
==================
Remove the "x" from my email address
Jerry Stuckle
JDS Computer Training Corp.
jstucklex(at)attglobal(dot)net
==================
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Re: Read info from webcam video [message #181914 is a reply to message #181894] |
Sat, 22 June 2013 17:52   |
Peter H. Coffin
Messages: 245 Registered: September 2010
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Senior Member |
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On Fri, 21 Jun 2013 06:14:25 -0400, Norman Peelman wrote:
> On 06/20/2013 10:31 PM, Peter H. Coffin wrote:
>> On Thu, 20 Jun 2013 19:14:15 -0400, Norman Peelman wrote:
>>> As long as he can grab the images from the cam via php (requires that
>>> the IP camera has an internal server) then it is quite easily done. As
>>> Jerry's response dictates. Examine the images looking for the tell-tale
>>> LED.
>>
>> And checking against previous images to see if they were off, and
>> selecting the appropriate image somehow to make the comparison with. And
>> it'll be especially fun if the camera's not set someplace where the LED
>> fills the entire sensor area...
>>
>
> Well, since the op said it would be flashing, I imagine you only need
> to find it 'on' at least once.
OP said "flashing" not "on". And I know plenty of things that use a
flashing power indicator to indicate an error condition, which is not
just plain "on" or "off".
--
67. No matter how many shorts we have in the system, my guards will be
instructed to treat every surveillance camera malfunction as a
full-scale emergency.
--Peter Anspach's list of things to do as an Evil Overlord
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Re: Read info from webcam video [message #181915 is a reply to message #181898] |
Sat, 22 June 2013 22:55  |
The Frog
Messages: 6 Registered: March 2013
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Junior Member |
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Just a passing thought, but some cameras have their own motion
detection built-in. Setting up the area of interest directly over the
flashing light, and adjusting the sensitivity threshold
appropriately, the camera may be able to generate a signal of sorts
such as SNMP or an email or even a structured data packet that you
could use. It might be worth investigating your cameras capabilities
or even investing in one that has such abilities.
Just a thought.
--
Cheers
The Frog
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