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Blob tracking Red returns Black

PostPosted: Fri Feb 08, 2008 3:18 pm
by Newbert
HI, Folks. I am trying to track the color red, but I'm getting a large blob where there is a large black area behind it. It is returning this as a red blob. My map is set for a single color (red). Specifically R: 208-240, G: 16-48, B: 16-48. AVRCamView indicates the black area to have values of 16 for R, G, and B. Am I wrong to assume the color of a pixel would have to fall in the range of all 3 to be returned as a tracked blob? Can anybody explain to me what I'm doing wrong?

Thanks

Re: Blob tracking Red returns Black

PostPosted: Sun Feb 10, 2008 7:54 pm
by johno
Hi Newbert,
Couple of questions for you:

-Does the blob fill the entire screen?

-Is the blob present regardless of what you point the camera at?

-Do other colors track properly (i.e., if you set it up to track a blue object, does it work)?

-Does the blob that fills the screen start as soon as you enable tracking?

-How are you powering the AVRcam? If it is from a 9V battery, are you sure it has sufficient power left in it? Probably 90% of the "oddities" people have found with the system have to do with a 9V battery that is almost depleted, and thus can't provide sufficient juice for the system to operate properly.

This info will help diagnose the situation...

Re: Blob tracking Red returns Black

PostPosted: Tue Feb 12, 2008 10:35 am
by Newbert
Thanks for the replies. I've included some screenshots that should help.

Image
Image

Image
Image

The large blob at the top of RedTrak.jpg is definitely the result of the darkness seen at the top of RedCapt.jpg. It does appear as soon as the tracking starts and stays as long as the cam is pointing as such. If I point the camera to a dark enough part of the room it will sometimes fill the whole screen. Other colors, namely blue, do track properly, so it is just red. I've tried Auto White Balance on and off but not much difference. The other "general" registers are disabled. RedCapt2 shows the same red object against a different background and as you can see I get other long horizontal blobs that extend the width of the screen. I am, of course, able to work around this by ignoring blobs that extend the width of the image but if there is something I could do that would be great. The power supply, BTW is not a 9V (I deemed those worthless long ago). I use a 9V wall wart (500mA) or a 7.2V AA battery pack both with same results so I'm fairly certain it is not the power supply.

Thanks Again,
Newbert

Re: Blob tracking Red returns Black

PostPosted: Mon Feb 18, 2008 6:17 am
by johno
Hmmm...interesting indeed. It looks like you are setting everything else up properly. I've done lots of test with the system tracking the color red and have never had an issue where it inadvertently tracks black as well. Couple of additional questions:

-I see that you have red setup in the eight color tracking slot. Its probably a long shot, but can you setup the same R-G-B bounds in the first color slot in the color map with AVRcamVIEW and report back if this makes a difference?

-If you hold up a black object that doesn't extend the full width of the screen, does it also report back as being red?

-Can you do a test where the top of the image has some other non-black color, with a black object extending the width of the image midway down the image?

Let me know what the above turns up...thanks.

Re: Blob tracking Red returns Black

PostPosted: Tue Feb 19, 2008 12:23 pm
by Newbert
I don't know how, but changing to the 1st color slot worked! Woo Hoo!

Thanks John