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Author Topic: Blackfin in a UAV  (Read 1131 times)

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Offline Joker94Topic starter

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Blackfin in a UAV
« on: May 20, 2010, 02:54:40 AM »
What do you guys think?

The UAV will be at a constant hight of 200 to 400 feet and it needs to be able to spot a person near a car.

Since i have no experience of the black fins i wouldnt know if it would work ok. would it it?

i dont need a specific answer just for people opinion on the matter

cheers

Joker94

Offline Webbot

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Re: Blackfin in a UAV
« Reply #1 on: May 20, 2010, 06:40:33 AM »
Bear in mind that cameras like the Blackfin generate a frame of pixels which is far too big to transmit to another processor. eg 320 x 200 pixels = 64,000 bytes
Equally 64k is a lot  of RAM.
Therefore all image processing is normally done on the camera.
The most common feature is to look for blobs eg any rectangles whose pixels are within a min/max colour range.
These blobs are then detected as the camera is transmitting the scan lines - ie the camera hardware doesn't need to store the whole image either.

So if the car is a red car and the person is wearing blue then you stand a chance of detecting and distinguishing them both. But if you need to detect any colour car and a person dressed in any colour then you've got a much bigger job as you are performing shape detection. You would probably need to write that code and then upload it to the Blackfin to replace its default image processing.
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Offline Joker94Topic starter

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Re: Blackfin in a UAV
« Reply #2 on: May 21, 2010, 06:54:12 AM »
thanks webbot

i think at this stage we are going with a surveillance style camera and a 10w video transmitter. an i am sure i will have a question or 2 over the next few months

Thanks for your help

Joker94

Offline Admin

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Re: Blackfin in a UAV
« Reply #3 on: May 31, 2010, 09:07:00 PM »
What do you mean by "needs to be able to spot a person near a car."

You mean like autonomous face detection? Or just enough pixels that if you looked at the video feed you could tell it was a person in the car?

Offline Joker94Topic starter

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Re: Blackfin in a UAV
« Reply #4 on: June 01, 2010, 02:13:38 AM »
It has to spot a person near a car from between 200 and 400 feet.

I have ruled out the blackfin though, going with a normal AV camera

i was looking at the blackfin as it had UART but i dont need it anymore.

Cheers

Joker94

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Re: Blackfin in a UAV
« Reply #5 on: June 01, 2010, 03:18:44 AM »
You didn't answer my question :P

Offline Joker94Topic starter

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Re: Blackfin in a UAV
« Reply #6 on: June 01, 2010, 03:44:47 AM »
Sorry admin.

no nothing that detailed, we just have to be able to see the dummy laying there so we can initiate the bottle drop rig.

Cheers

Joker94

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Re: Blackfin in a UAV
« Reply #7 on: June 01, 2010, 03:49:54 AM »
The reason I asked is I wasn't sure if you wanted on-board computer vision, or just a camera for normal video.

For normal video, the Blackfin/CMUcam is definitely *NOT* a good choice :P

 


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