# Ros2 Perception

> Perception: image_transport, cv_bridge, vision_msgs, depth_image_proc, laser_geometry, pcl_ros.

- **Type:** Skill
- **Install:** `agentstack add skill-leehyunbin0131-claude-ros2-skills-ros2-perception`
- **Verified:** Yes — security-reviewed for prompt injection and unsafe behavior
- **Seller:** [Leehyunbin0131](https://agentstack.voostack.com/s/leehyunbin0131)
- **Installs:** 0
- **Category:** [AI & ML](https://agentstack.voostack.com/c/ai-and-ml)
- **Latest version:** 0.1.0
- **License:** MIT
- **Upstream author:** [Leehyunbin0131](https://github.com/Leehyunbin0131)
- **Source:** https://github.com/Leehyunbin0131/claude-ros2-skills/tree/main/skills/ros2-perception

## Install

```sh
agentstack add skill-leehyunbin0131-claude-ros2-skills-ros2-perception
```

Requires the [AgentStack CLI](https://agentstack.voostack.com/docs/cli). Works with Claude Code, Cursor, and any MCP-compatible agent.

## About

# ROS 2 Perception & Computer Vision Instructions (Ubuntu 24.04 LTS & ROS 2 Jazzy)

## 1. Core Principles & Architecture
- **Target OS & ROS Distro**: **Ubuntu 24.04 LTS & ROS 2 Jazzy Jalisco**.
- **Perception Pipeline**: Handles image streams, OpenCV conversions (`cv_bridge`), 2D/3D object detections (`vision_msgs`), depth image processing (`depth_image_proc`), LiDAR scan projection (`laser_geometry`), 3D-to-2D scan conversion (`pointcloud_to_laserscan`), and Point Cloud Library processing (`pcl_ros`).
- **Zero-Hallucination Policy**: Always verify C++ and Python class names, message fields, and plugin encodings against official ROS 2 Jazzy documentation.

## 2. Official Documentation Catalog

### A. Master Documentation & Package Indices
- **image_transport Package**: `https://docs.ros.org/en/jazzy/p/image_transport/`
- **cv_bridge Package**: `https://docs.ros.org/en/jazzy/p/cv_bridge/`
- **vision_msgs Package**: `https://docs.ros.org/en/jazzy/p/vision_msgs/`
- **depth_image_proc Package**: `https://docs.ros.org/en/jazzy/p/depth_image_proc/`
- **pointcloud_to_laserscan Package**: `https://docs.ros.org/en/jazzy/p/pointcloud_to_laserscan/`
- **laser_geometry Package**: `https://index.ros.org/p/laser_geometry/`
- **pcl_ros Package**: `https://docs.ros.org/en/jazzy/p/pcl_ros/`

## 3. Key Concepts & Patterns

### A. `cv_bridge` OpenCV Conversion (C++)
```cpp
#include 
#include 
#include 
#include 
#include 

void process_image(const sensor_msgs::msg::Image::ConstSharedPtr & msg) {
  cv_bridge::CvImagePtr cv_ptr = cv_bridge::toCvCopy(msg, sensor_msgs::image_encodings::BGR8);
  cv::circle(cv_ptr->image, cv::Point(50, 50), 10, CV_RGB(255, 0, 0), 2);
  sensor_msgs::msg::Image::SharedPtr out_msg = cv_ptr->toImageMsg();
}
```

### B. `pcl_ros` PointCloud Conversion (C++)
```cpp
#include 
#include 
#include 
#include 

void filter_cloud(const sensor_msgs::msg::PointCloud2::SharedPtr msg) {
  pcl::PointCloud::Ptr pcl_cloud(new pcl::PointCloud);
  pcl::fromROSMsg(*msg, *pcl_cloud);

  pcl::PointCloud::Ptr filtered(new pcl::PointCloud);
  pcl::VoxelGrid sor;
  sor.setInputCloud(pcl_cloud);
  sor.setLeafSize(0.05f, 0.05f, 0.05f);
  sor.filter(*filtered);

  sensor_msgs::msg::PointCloud2 output_msg;
  pcl::toROSMsg(*filtered, output_msg);
}
```

## 4. Symptom -> Root Cause -> Action

| Symptom | Likely root cause | Action |
| :--- | :--- | :--- |
| Image topic listed but callback never fires | QoS mismatch: camera drivers publish BestEffort, subscriber defaults Reliable | Subscribe with `SensorDataQoS`; confirm with `ros2 topic info  -v` |
| `cv_bridge` throws encoding exception | Requested encoding doesn't match source (`bgr8` vs `rgb8`, `16UC1` depth) | Use `toCvCopy(msg, msg->encoding)` (passthrough) or convert explicitly; never assume `bgr8` for depth |
| Depth values look 1000x off or all ~0 | `16UC1` is millimeters, `32FC1` is meters — unit confusion | Check `msg->encoding` before scaling; divide 16UC1 by 1000.0 for meters |
| Point cloud misaligned with the RGB image | Depth not registered into the color optical frame | Use the `depth_registered` topic or `depth_image_proc` register node; verify both `frame_id`s |
| `pointcloud_to_laserscan` outputs empty scans | `min_height`/`max_height` band excludes all points, or `target_frame` transform missing | Widen the height band around the sensor's actual Z; check TF to `target_frame` |
| Detection boxes drawn at wrong image positions | Processing the rectified topic but projecting with the raw camera matrix (or vice versa) | Pair `image_rect` with `P` (projection) matrix, raw `image` with `K`; don't mix |
| High CPU from image subscribers | Subscribing raw full-resolution images over the network | Use `image_transport` compressed transport, or throttle/downscale before processing |

## Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

- **Author:** [Leehyunbin0131](https://github.com/Leehyunbin0131)
- **Source:** [Leehyunbin0131/claude-ros2-skills](https://github.com/Leehyunbin0131/claude-ros2-skills)
- **License:** MIT

Install and usage instructions live in the source repository linked above.

## Pricing

- **Free** — Free

## Security capabilities

Automated source analysis of v0.1.0 — what this tool can access:

- **Network access:** no
- **Filesystem access:** no
- **Shell / process execution:** no
- **Environment & secrets:** no
- **Dynamic code execution:** no

*"Yes" means the capability is present in the source — more access means more to trust, not that it is unsafe.*


## Versions

- **0.1.0** — security scan: passed — Imported from the upstream source.

## Links

- Listing page: https://agentstack.voostack.com/l/skill-leehyunbin0131-claude-ros2-skills-ros2-perception
- Seller: https://agentstack.voostack.com/s/leehyunbin0131
- Browse the marketplace: https://agentstack.voostack.com/browse

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Listed on AgentStack — the marketplace for AI agent skills and MCP servers. Every listing is security-reviewed. Creators keep 70%.