Video

Nodes

rf_detector

rf_detector is a categorical object detector using Random Forests. It runs a ROS node that expects stereo input data (with textured light) input from the texture_light_on_off node.

Subscribed topics

rf_detector subscribes to three ROS topics:

• /t_on_off/image

• /t_on_off/caminfo

• /t_on_off/dense_cloud

After the rf_detector node receive all three topics, it will start detecting objects in the image.

launch files

rf_pcd_hogshape_detector_3Class.launch will start the rf_detector with some default parameter settings. There are five groups of parameters which need to be set.

1. table-top object related parameters :

• PrineTableFlag -- if true, do table-top object candidate reasoning.

• max_depth -- the maximum depth that the system will search for objects.
• min_depth -- the minimum depth that the system will search for objects.
• plane_axis_x -- the x component of the surface number orientation of the table in the image_frame.
• plane_axis_y -- the y component of the surface number orientation of the table in the image_frame.
• plane_axis_z -- the z component of the surface number orientation of the table in the image_frame.
• eps_angle -- the tolerance of the different between the estimated surface norm direction and the one set by plane_axis.

2. patch sample related parameters

• Radius -- Radius of corresponding the 3d sphere to be sampled.

• SampleStep -- The step size (in pixel) between two nearby sampled patches .

• winStep -- The incremental step of the patch size in pixel.
• numCellPerWin -- the number of cells in each patch for both vertical and horizontal direction.
• numCellPerBlock -- the number of cells in each Block for both vertical and horizontal direction.
• padding -- The padding in pixel for both top-left and bottom-right corner.

• ObjHeight2winHeightRatio -- Object height / Patch height

3. model related parameters

• !RFmodel_filename -- the file describing the trained random forest.

• FgBgProb_filename -- the Foreground/Background probability of each lead nodes in the random forest.

• ClassIdBinary_filename -- the Class Id of each trained Foreground patch.

• NormVotesBinary_filename --The normalized voting direction, the relative object height to patch height, the aspect ratio of the object.

• MaxClassId -- the Maximum Class Id.

• ClassId2ViewObjClassMapFile -- the file which map each Class Id into object Class index and Viewpoint index.

4. voting related parameters

• hitThreshold -- The minimum Foreground/Background ratio of a node to cast votes.

• MeanShiftMaxIter -- The maximum mean-shift iteration to search for local mode.

• ObjHeightStep -- The incremental step of the object height in pixel.

• !ObjASStep -- The incremental step of the object aspect ratio.

5. detection post processing related parameters

• RectOverlapRatio -- The threshold to decide if two bounding boxes are overlapping each other.

• ConfThre -- It defines the minimum score for a object detector could return.