Reference Path Visualization¶
Class: ReferencePathVisualizationBlockV1
Draw a static reference path on an image to visualize an expected or ideal route, displaying a predefined polyline path that can be compared against actual object trajectories for path deviation analysis and route compliance monitoring.
How This Block Works¶
This block takes an image and reference path coordinates (a list of points defining a path) and draws a static polyline path representing an expected route or ideal trajectory. The block:
- Takes an image and reference path coordinates (a list of points: [(x1, y1), (x2, y2), (x3, y3), ...]) as input
- Converts the coordinate list into a polyline path connecting the points in sequence
- Draws the reference path as a polyline using the specified color and thickness
- Returns an annotated image with the reference path overlaid on the original image
The block visualizes a static, predefined reference path that represents where objects should ideally move or what route they should follow. Unlike Trace Visualization (which draws dynamic paths based on actual tracked object movement), Reference Path Visualization draws a fixed path that remains constant. This reference path serves as a baseline for comparison, allowing you to visualize the expected route alongside actual object trajectories. The path is drawn as a continuous line connecting all the specified points, creating a visual guide for route compliance, path deviation analysis, or navigation workflows. This block is commonly used with Path Deviation analytics blocks to visually display the reference path that actual object trajectories will be compared against.
Common Use Cases¶
- Path Deviation Visualization: Visualize a reference path alongside actual object trajectories to compare expected routes against actual movement for path deviation detection, route compliance monitoring, or navigation validation workflows
- Route Planning and Navigation: Display predefined routes, navigation paths, or expected travel routes that objects should follow for route planning, navigation systems, or waypoint visualization applications
- Compliance and Safety Monitoring: Visualize expected paths for safety monitoring, compliance workflows, or route validation where objects need to follow specific paths (e.g., vehicles on designated lanes, robots on expected routes)
- Industrial and Logistics Applications: Display reference paths for conveyor systems, automated guided vehicles (AGVs), or manufacturing workflows where objects must follow predefined routes for process control or quality assurance
- Security and Access Control: Visualize expected movement paths for security monitoring, access control, or surveillance workflows where deviations from expected routes need to be identified
- Training and Documentation: Display reference paths in training materials, documentation, or demonstrations to show expected object behavior, routes, or movement patterns for educational or reference purposes
Connecting to Other Blocks¶
The annotated image from this block can be connected to:
- Path Deviation analytics blocks to compare tracked object trajectories against the visualized reference path for deviation analysis
- Other visualization blocks (e.g., Trace Visualization, Bounding Box Visualization, Label Visualization) to combine reference path visualization with actual object tracking visualizations for comprehensive path comparison
- Tracking blocks (e.g., Byte Tracker) where the reference path can serve as a visual baseline for comparing actual tracked object trajectories
- Data storage blocks (e.g., Local File Sink, CSV Formatter, Roboflow Dataset Upload) to save images with reference paths for documentation, reporting, or analysis
- Webhook blocks to send visualized results with reference paths to external systems, APIs, or web applications for display in dashboards or monitoring tools
- Notification blocks (e.g., Email Notification, Slack Notification) to send annotated images with reference paths as visual evidence in alerts or reports
- Video output blocks to create annotated video streams or recordings with reference paths for live monitoring, path visualization, or post-processing analysis
Type identifier¶
Use the following identifier in step "type" field: roboflow_core/reference_path_visualization@v1to add the block as
as step in your workflow.
Properties¶
| Name | Type | Description | Refs |
|---|---|---|---|
name |
str |
Enter a unique identifier for this step.. | ❌ |
copy_image |
bool |
Enable this option to create a copy of the input image for visualization, preserving the original. Use this when stacking multiple visualizations.. | ✅ |
reference_path |
List[Any] |
Reference path coordinates in the format [(x1, y1), (x2, y2), (x3, y3), ...] defining the expected or ideal route. The path is drawn as a polyline connecting these points in sequence, creating a continuous line representing the reference trajectory. Typically connected from Path Deviation analytics blocks or defined manually as an expected route. Must contain at least two points to form a valid path.. | ✅ |
color |
str |
Color of the reference path. Can be specified as a color name (e.g., 'WHITE', 'GREEN', 'BLUE'), hex color code (e.g., '#5bb573', '#FFFFFF'), or RGB format (e.g., 'rgb(91, 181, 115)'). The reference path is drawn in this color with the specified thickness.. | ✅ |
thickness |
int |
Thickness of the reference path line in pixels. Controls how thick the reference path appears. Higher values create thicker, more visible paths, while lower values create thinner, more subtle paths. Must be greater than or equal to zero. Typical values range from 1 to 5 pixels.. | ✅ |
The Refs column marks possibility to parametrise the property with dynamic values available
in workflow runtime. See Bindings for more info.
Available Connections¶
Compatible Blocks
Check what blocks you can connect to Reference Path Visualization in version v1.
- inputs:
Email Notification,Contrast Equalization,PTZ Tracking (ONVIF),Instance Segmentation Model,Google Vision OCR,Grid Visualization,S3 Sink,Stability AI Image Generation,Model Comparison Visualization,Identify Changes,Absolute Static Crop,Keypoint Visualization,SIFT,Trace Visualization,Roboflow Dataset Upload,Twilio SMS/MMS Notification,QR Code Generator,Buffer,Model Monitoring Inference Aggregator,GLM-OCR,Reference Path Visualization,Halo Visualization,OCR Model,SIFT Comparison,VLM As Classifier,VLM As Detector,Image Preprocessing,Crop Visualization,OpenAI,Identify Outliers,Label Visualization,Classification Label Visualization,Pixelate Visualization,Local File Sink,Twilio SMS Notification,Email Notification,OpenAI,Qwen3.5-VL,Stitch OCR Detections,Corner Visualization,Stitch Images,Background Subtraction,Stitch OCR Detections,LMM For Classification,EasyOCR,Morphological Transformation,CSV Formatter,Line Counter,OpenAI,Clip Comparison,Image Threshold,Background Color Visualization,Anthropic Claude,Google Gemini,Camera Calibration,Halo Visualization,Stability AI Outpainting,Roboflow Custom Metadata,CogVLM,OpenAI,Single-Label Classification Model,Ellipse Visualization,Dynamic Zone,VLM As Classifier,Heatmap Visualization,Image Convert Grayscale,Detections Consensus,Triangle Visualization,Image Blur,Depth Estimation,Size Measurement,Dimension Collapse,Color Visualization,SIFT Comparison,Camera Focus,Text Display,Anthropic Claude,Dot Visualization,Image Slicer,Template Matching,Keypoint Detection Model,Polygon Visualization,Florence-2 Model,Motion Detection,Circle Visualization,Blur Visualization,Multi-Label Classification Model,Google Gemini,LMM,Slack Notification,Icon Visualization,Detections List Roll-Up,Camera Focus,Stability AI Inpainting,Polygon Visualization,Detection Event Log,Webhook Sink,Polygon Zone Visualization,Perspective Correction,Florence-2 Model,Anthropic Claude,Mask Visualization,Google Gemini,Image Contours,Dynamic Crop,Roboflow Dataset Upload,Clip Comparison,Llama 3.2 Vision,Distance Measurement,JSON Parser,VLM As Detector,Pixel Color Count,Object Detection Model,Image Slicer,Line Counter Visualization,Relative Static Crop,Line Counter,Bounding Box Visualization - outputs:
Dominant Color,Email Notification,Instance Segmentation Model,ByteTrack Tracker,Google Vision OCR,Contrast Equalization,Stability AI Image Generation,Model Comparison Visualization,Absolute Static Crop,Keypoint Visualization,Trace Visualization,SIFT,Roboflow Dataset Upload,Twilio SMS/MMS Notification,CLIP Embedding Model,Buffer,SAM 3,GLM-OCR,Reference Path Visualization,Halo Visualization,OCR Model,SIFT Comparison,VLM As Classifier,Time in Zone,Detections Stabilizer,VLM As Detector,Image Preprocessing,SORT Tracker,Perception Encoder Embedding Model,Crop Visualization,OpenAI,OpenAI,Label Visualization,Pixelate Visualization,Classification Label Visualization,Qwen3.5-VL,Corner Visualization,Stitch Images,Background Subtraction,LMM For Classification,EasyOCR,Morphological Transformation,Qwen2.5-VL,SAM 3,OpenAI,Clip Comparison,Single-Label Classification Model,Background Color Visualization,Anthropic Claude,Image Threshold,Google Gemini,Camera Calibration,Stability AI Outpainting,Halo Visualization,CogVLM,OpenAI,Single-Label Classification Model,Ellipse Visualization,Detections Stitch,VLM As Classifier,Heatmap Visualization,Image Convert Grayscale,Triangle Visualization,Semantic Segmentation Model,Image Blur,Depth Estimation,Barcode Detection,Color Visualization,Camera Focus,Text Display,Anthropic Claude,Dot Visualization,Image Slicer,SmolVLM2,SAM 3,Template Matching,Keypoint Detection Model,Polygon Visualization,Florence-2 Model,Motion Detection,Circle Visualization,Blur Visualization,Qwen3-VL,Multi-Label Classification Model,Google Gemini,LMM,Icon Visualization,Camera Focus,Stability AI Inpainting,Polygon Visualization,Polygon Zone Visualization,Florence-2 Model,Gaze Detection,Perspective Correction,Anthropic Claude,Instance Segmentation Model,Mask Visualization,Moondream2,QR Code Detection,Google Gemini,Image Contours,Clip Comparison,YOLO-World Model,Dynamic Crop,Roboflow Dataset Upload,Llama 3.2 Vision,Seg Preview,Keypoint Detection Model,Object Detection Model,Pixel Color Count,VLM As Detector,Object Detection Model,Image Slicer,Byte Tracker,Line Counter Visualization,Relative Static Crop,Multi-Label Classification Model,OC-SORT Tracker,Bounding Box Visualization,Segment Anything 2 Model
Input and Output Bindings¶
The available connections depend on its binding kinds. Check what binding kinds
Reference Path Visualization in version v1 has.
Bindings
-
input
image(image): The image to visualize on..copy_image(boolean): Enable this option to create a copy of the input image for visualization, preserving the original. Use this when stacking multiple visualizations..reference_path(list_of_values): Reference path coordinates in the format [(x1, y1), (x2, y2), (x3, y3), ...] defining the expected or ideal route. The path is drawn as a polyline connecting these points in sequence, creating a continuous line representing the reference trajectory. Typically connected from Path Deviation analytics blocks or defined manually as an expected route. Must contain at least two points to form a valid path..color(string): Color of the reference path. Can be specified as a color name (e.g., 'WHITE', 'GREEN', 'BLUE'), hex color code (e.g., '#5bb573', '#FFFFFF'), or RGB format (e.g., 'rgb(91, 181, 115)'). The reference path is drawn in this color with the specified thickness..thickness(integer): Thickness of the reference path line in pixels. Controls how thick the reference path appears. Higher values create thicker, more visible paths, while lower values create thinner, more subtle paths. Must be greater than or equal to zero. Typical values range from 1 to 5 pixels..
-
output
image(image): Image in workflows.
Example JSON definition of step Reference Path Visualization in version v1
{
"name": "<your_step_name_here>",
"type": "roboflow_core/reference_path_visualization@v1",
"image": "$inputs.image",
"copy_image": true,
"reference_path": "$inputs.expected_path",
"color": "WHITE",
"thickness": 2
}