heatmap_visualizer#
Purpose#
heatmap_visualizer is a package for visualizing heatmap of detected 3D objects' positions on the BEV space.
This package is used for qualitative evaluation and trend analysis of the detector, it means, for instance, the heatmap shows "This detector performs good for near around of our vehicle, but far is bad".
How to run#
ros2 launch heatmap_visualizer heatmap_visualizer.launch.xml input/objects:=<DETECTED_OBJECTS_TOPIC>
Inner-workings / Algorithms#
In this implementation, create heatmap of the center position of detected objects for each classes, for instance, CAR, PEDESTRIAN, etc, and publish them as occupancy grid maps.
In the above figure, the pink represents high detection frequency area and blue one is low, or black represents there is no detection.
As inner-workings, add center positions of detected objects to index of each corresponding grid map cell in a buffer.
The created heatmap will be published by each specific frame, which can be specified with frame_count. Note that the buffer to be add the positions is not reset per publishing.
When publishing, firstly these values are normalized to [0, 1] using maximum and minimum values in the buffer. Secondly, they are scaled to integer in [0, 100] because nav_msgs::msg::OccupancyGrid only allow the value in [0, 100].
Inputs / Outputs#
Input#
| Name | Type | Description |
|---|---|---|
~/input/objects |
autoware_auto_perception_msgs::msg::DetectedObjects |
detected objects |
Output#
| Name | Type | Description |
|---|---|---|
~/output/objects/<CLASS_NAME> |
nav_msgs::msg::OccupancyGrid |
visualized heatmap |
Parameters#
Core Parameters#
| Name | Type | Default Value | Description |
|---|---|---|---|
frame_count |
int | 50 |
The number of frames to publish heatmap |
map_frame |
string | base_link |
the frame of heatmap to be respected |
map_length |
float | 200.0 |
the length of map in meter |
map_resolution |
float | 0.8 |
the resolution of map |
use_confidence |
bool | false |
the flag if use confidence score as heatmap value |
rename_car_to_truck_and_bus |
bool | true |
the flag if rename car to truck or bus |
Assumptions / Known limits#
The heatmap depends on the data to be used, so if the objects in data are sparse the heatmap will be sparse.