Heatmap Visualization¶
Class: HeatmapVisualizationBlockV1
Source: inference.core.workflows.core_steps.visualizations.heatmap.v1.HeatmapVisualizationBlockV1
Draw heatmaps on an image based on provided detections. Heat accumulates over time and is drawn as a semi-transparent overlay of blurred circles.
How This Block Works¶
This block takes an image and detection predictions and draws a heatmap. The block:
- Takes an image and predictions as input.
- Accumulates heat based on the position of detections.
- Draws a semi-transparent overlay of blurred circles representing the heat.
Common Use Cases¶
- Density Analysis: Visualize the density of objects in a scene.
- Traffic Monitoring: Identify high-traffic areas.
- Retail Analytics: Analyze foot traffic in stores.
Type identifier¶
Use the following identifier in step "type" field: roboflow_core/heatmap_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.. | ✅ |
position |
str |
The position of the heatmap relative to the detection.. | ✅ |
opacity |
float |
Opacity of the overlay mask, between 0 and 1.. | ✅ |
radius |
int |
Radius of the heat circle.. | ✅ |
kernel_size |
int |
Kernel size for blurring the heatmap.. | ✅ |
top_hue |
int |
Hue at the top of the heatmap. Defaults to 0 (red).. | ✅ |
low_hue |
int |
Hue at the bottom of the heatmap. Defaults to 125 (blue).. | ✅ |
ignore_stationary |
bool |
If True, only moving objects (based on tracker ID) will contribute to the heatmap.. | ✅ |
motion_threshold |
int |
Minimum movement in pixels required to consider an object as moving.. | ✅ |
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 Heatmap Visualization in version v1.
- inputs:
Image Threshold,Email Notification,Corner Visualization,Roboflow Dataset Upload,Object Detection Model,Stitch OCR Detections,Gaze Detection,Stability AI Image Generation,Time in Zone,Grid Visualization,Dynamic Crop,Image Slicer,Image Preprocessing,Instance Segmentation Model,SIFT,Line Counter Visualization,Detections Combine,Trace Visualization,Halo Visualization,ByteTrack Tracker,Roboflow Custom Metadata,Pixelate Visualization,Circle Visualization,S3 Sink,Detections Classes Replacement,Keypoint Detection Model,Twilio SMS Notification,Halo Visualization,SIFT Comparison,Anthropic Claude,OC-SORT Tracker,Polygon Visualization,Detections Consensus,Cosine Similarity,Identify Changes,Crop Visualization,Roboflow Dataset Upload,Mask Visualization,Detection Offset,Heatmap Visualization,Webhook Sink,Detections List Roll-Up,Google Vision OCR,Florence-2 Model,Florence-2 Model,VLM As Classifier,Overlap Filter,Anthropic Claude,OpenAI,VLM As Detector,OpenAI,PTZ Tracking (ONVIF),Bounding Rectangle,Background Color Visualization,Template Matching,Anthropic Claude,Background Subtraction,SIFT Comparison,Multi-Label Classification Model,Keypoint Visualization,Time in Zone,Detections Filter,Stitch OCR Detections,LMM,Detections Merge,Detections Transformation,Identify Outliers,SAM 3,Motion Detection,Dynamic Zone,Seg Preview,Single-Label Classification Model,Object Detection Model,Roboflow Vision Events,VLM As Classifier,Detections Stitch,Triangle Visualization,Distance Measurement,Google Gemini,Path Deviation,Image Slicer,Image Contours,Model Comparison Visualization,Stability AI Outpainting,Stitch Images,Image Blur,Ellipse Visualization,OpenAI,Time in Zone,Depth Estimation,EasyOCR,Absolute Static Crop,JSON Parser,CogVLM,Google Gemini,Velocity,Relative Static Crop,Morphological Transformation,LMM For Classification,Detection Event Log,Dot Visualization,GLM-OCR,Model Monitoring Inference Aggregator,Keypoint Detection Model,Pixel Color Count,Image Convert Grayscale,Icon Visualization,QR Code Generator,Detections Stabilizer,Camera Focus,SAM 3,OCR Model,Text Display,Reference Path Visualization,Instance Segmentation Model,Llama 3.2 Vision,CSV Formatter,SORT Tracker,Byte Tracker,Label Visualization,Classification Label Visualization,Byte Tracker,Segment Anything 2 Model,Polygon Zone Visualization,Stability AI Inpainting,Google Gemini,SAM 3,Perspective Correction,Camera Calibration,Qwen3.5-VL,Email Notification,Contrast Equalization,Line Counter,Path Deviation,Byte Tracker,Line Counter,Color Visualization,OpenAI,Local File Sink,Mask Area Measurement,Twilio SMS/MMS Notification,YOLO-World Model,Clip Comparison,Blur Visualization,Bounding Box Visualization,Camera Focus,Polygon Visualization,Moondream2,VLM As Detector,Slack Notification - outputs:
Stitch Images,Image Threshold,Corner Visualization,Image Blur,Ellipse Visualization,OpenAI,Roboflow Dataset Upload,Object Detection Model,Barcode Detection,Depth Estimation,Gaze Detection,EasyOCR,Absolute Static Crop,Multi-Label Classification Model,CogVLM,Google Gemini,Stability AI Image Generation,Time in Zone,Dynamic Crop,Instance Segmentation Model,Image Slicer,Image Preprocessing,SIFT,Relative Static Crop,Morphological Transformation,Line Counter Visualization,Trace Visualization,LMM For Classification,Halo Visualization,Dot Visualization,ByteTrack Tracker,GLM-OCR,Keypoint Detection Model,Pixel Color Count,Pixelate Visualization,Circle Visualization,Semantic Segmentation Model,Image Convert Grayscale,Icon Visualization,Keypoint Detection Model,Detections Stabilizer,Halo Visualization,Camera Focus,Anthropic Claude,SAM 3,OC-SORT Tracker,OCR Model,Polygon Visualization,Text Display,Qwen2.5-VL,Reference Path Visualization,Instance Segmentation Model,Llama 3.2 Vision,Qwen3-VL,Crop Visualization,Roboflow Dataset Upload,Mask Visualization,Moondream2,CLIP Embedding Model,SORT Tracker,Heatmap Visualization,Label Visualization,Google Vision OCR,Byte Tracker,Classification Label Visualization,Florence-2 Model,Segment Anything 2 Model,Florence-2 Model,VLM As Detector,Polygon Zone Visualization,Stability AI Inpainting,VLM As Classifier,Google Gemini,SAM 3,Perspective Correction,Anthropic Claude,OpenAI,Camera Calibration,VLM As Detector,OpenAI,Qwen3.5-VL,Template Matching,Background Color Visualization,Anthropic Claude,Email Notification,Background Subtraction,SIFT Comparison,Contrast Equalization,Multi-Label Classification Model,Keypoint Visualization,LMM,SmolVLM2,Single-Label Classification Model,Perception Encoder Embedding Model,SAM 3,Motion Detection,Seg Preview,Single-Label Classification Model,Color Visualization,Object Detection Model,OpenAI,Dominant Color,Roboflow Vision Events,QR Code Detection,VLM As Classifier,Detections Stitch,Clip Comparison,YOLO-World Model,Triangle Visualization,Buffer,Clip Comparison,Twilio SMS/MMS Notification,Bounding Box Visualization,Blur Visualization,Camera Focus,Polygon Visualization,Google Gemini,Image Slicer,Image Contours,Model Comparison Visualization,Stability AI Outpainting
Input and Output Bindings¶
The available connections depend on its binding kinds. Check what binding kinds
Heatmap 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..predictions(Union[keypoint_detection_prediction,rle_instance_segmentation_prediction,instance_segmentation_prediction,object_detection_prediction]): Model predictions to visualize..metadata(video_metadata): Video metadata containing video_identifier to maintain separate state for different videos..position(string): The position of the heatmap relative to the detection..opacity(float): Opacity of the overlay mask, between 0 and 1..radius(integer): Radius of the heat circle..kernel_size(integer): Kernel size for blurring the heatmap..top_hue(integer): Hue at the top of the heatmap. Defaults to 0 (red)..low_hue(integer): Hue at the bottom of the heatmap. Defaults to 125 (blue)..ignore_stationary(boolean): If True, only moving objects (based on tracker ID) will contribute to the heatmap..motion_threshold(integer): Minimum movement in pixels required to consider an object as moving..
-
output
image(image): Image in workflows.
Example JSON definition of step Heatmap Visualization in version v1
{
"name": "<your_step_name_here>",
"type": "roboflow_core/heatmap_visualization@v1",
"image": "$inputs.image",
"copy_image": true,
"predictions": "$steps.object_detection_model.predictions",
"metadata": "$inputs.video_metadata",
"position": "BOTTOM_CENTER",
"opacity": 0.2,
"radius": 40,
"kernel_size": 25,
"top_hue": 0,
"low_hue": 125,
"ignore_stationary": true,
"motion_threshold": 25
}