Region of interest functionality

Introduction

The region of interest (ROI) functionality is contained in an internal ROI component and can only be used through the software components providing a ROI functionality.

The ROI functionality is provided by the ItemPick and BoxPick modules.

Region of interest

A region of interest (ROI) defines a volume in space which is of interest for a specific user-application. A ROI can narrow the volume where a load carrier is searched for, or select a volume which only contains items to be detected and/or grasped. Processing times can significantly decrease when using a ROI.

Currently, regions of interest of the following types (type) are supported:

  • BOX, with dimensions box.x, box.y, box.z.
  • SPHERE, with radius sphere.radius.

The user can specify the region of interest pose in the camera or the external coordinate system. External can only be chosen if a Hand-eye calibration is available. When the rc_visard is robot mounted, and the region of interest is defined in the external frame, the current robot pose must be given to every detect service call that uses this region of interest.

The rc_visard can persistently store up to 50 different regions of interest, each one identified by a different id. The configuration of regions of interest is normally performed offline, during the set up of the desired application. This can be done via the REST-API interface or in the rc_visard Web GUI on the page of the module offering the region of interest functionality.

Note

The configured regions of interest are persistent even over firmware updates and rollbacks.

Parameters

The ROI component does not have any parameters.

Services

The user can explore and call the ROI component’s services, e.g. for development and testing, using the REST-API interface or the rc_visard Web GUI page of the module offering the ROI functionality.

Each service response contains a return_code, which consists of a value plus an optional message. A successful service returns with a return_code value of 0. Negative return_code values indicate that the service failed. Positive return_code values indicate that the service succeeded with additional information. The smaller value is selected in case a service has multiple return_code values, but all messages are appended in the return_code message.

The following table contains a list of common codes:

Table 50 Return codes of the region of interest services
Code Description
0 Success
-1 An invalid argument was provided
-10 New element could not be added as the maximum storage capacity of regions of interest has been exceeded
10 The maximum storage capacity of regions of interest has been reached
11 An existent persistent model was overwritten by the call to set_region_of_interest

All software components providing the ROI functionality offer the following services.

set_region_of_interest

Persistently stores a region of interest on the rc_visard. All configured regions of interest are persistent over firmware updates and rollbacks.

The definition for the request arguments with corresponding datatypes is:

{
  "args": {
    "region_of_interest": {
      "box": {
        "x": "float64",
        "y": "float64",
        "z": "float64"
      },
      "id": "string",
      "pose": {
        "orientation": {
          "w": "float64",
          "x": "float64",
          "y": "float64",
          "z": "float64"
        },
        "position": {
          "x": "float64",
          "y": "float64",
          "z": "float64"
        }
      },
      "pose_frame": "string",
      "sphere": {
        "radius": "float64"
      },
      "type": "string"
    }
  }
}

Details for the definition of the region_of_interest type are given in Region of interest.

The definition for the response with corresponding datatypes is:

{
  "name": "set_region_of_interest",
  "response": {
    "return_code": {
      "message": "string",
      "value": "int16"
    }
  }
}

get_regions_of_interest

Returns the configured regions of interest with the requested region_of_interest_ids. If no region_of_interest_ids are provided, all configured regions of interest are returned.

The definition for the request arguments with corresponding datatypes is:

{
  "args": {
    "region_of_interest_ids": [
      "string"
    ]
  }
}

The definition for the response with corresponding datatypes is:

{
  "name": "get_regions_of_interest",
  "response": {
    "regions_of_interest": [
      {
        "box": {
          "x": "float64",
          "y": "float64",
          "z": "float64"
        },
        "id": "string",
        "pose": {
          "orientation": {
            "w": "float64",
            "x": "float64",
            "y": "float64",
            "z": "float64"
          },
          "position": {
            "x": "float64",
            "y": "float64",
            "z": "float64"
          }
        },
        "pose_frame": "string",
        "sphere": {
          "radius": "float64"
        },
        "type": "string"
      }
    ],
    "return_code": {
      "message": "string",
      "value": "int16"
    }
  }
}

delete_regions_of_interest

Deletes the configured regions of interest with the requested region_of_interest_ids. All regions of interest to be deleted must be explicitly stated in region_of_interest_ids.

The definition for the request arguments with corresponding datatypes is:

{
  "args": {
    "region_of_interest_ids": [
      "string"
    ]
  }
}

The definition for the response with corresponding datatypes is:

{
  "name": "delete_regions_of_interest",
  "response": {
    "return_code": {
      "message": "string",
      "value": "int16"
    }
  }
}