[Java-player-users] problems using blobfinder

[Alberto A. <ame...@IC...>]

Hello everybody,

This is the first time I am using javaclient and also Player/Gazebo. I 
am trying to detect a blue cylinder using blobfinder, but it's not 
working. I don't know if my problem is the way I am using the java 
client, or might be related with the color file in cmvision, or other 
things.

In the world file, I have a Pioneer2AT robot with a SonyVID30 camera, 
and a couple of SimpleSolids, one of which is a cylinder, with 
<color>0.0 0.0 1</color> (the others are not blue).

Then, in the player file, I have

driver
(
     name "gz_camera"
     provides ["camera:0"]
     gz_id "camera1"
)

driver
(
     name "cmvision"
     provides ["blobfinder:0"]
     requires ["camera:0"]
     colorfile ["colorfile"]
)

The client code I am trying is:

PlayerClient robot = new PlayerClient("localhost", 6665);
BlobfinderInterface bfi = new robot.requestInterfaceBlobFinder(0,'r');
short numBlobs = 0;
bfi.setTrackingColor(0,0,0,0,250,255);
while (true) {
    bfi.readData();
    numBlobs = bfi.getBlobCount();
    System.out.println("num blobs="+numBlobs);
}

I get different values back for num blobs (0, 10, 88, 4608, ...), and 
also sometimes in the client I get an "outofBounds" exception,
"Error when reading payload: java.lang.ArrayIndexOutOfBoundsException: 
256", I guess that the number of "detected" blobs might be too big.

Anybody can help???



Many thanks,

Alberto Amengual