Add LISA for audience segmentation and CSRNet for heatmap generation

Crowd_Monitoring/LISA_Heatmap/API_usage.md

@@ -0,0 +1,66 @@
+
+---
+# Crowd Density API – Usage Guide
+
+This API processes uploaded video frames (images) and returns:  
+- **Estimated people count** in the stands (via CSRNet + LISASegmentor).  
+- **Heatmap image** (PNG format) showing density distribution.  
+
+---
+
+## Base URL
+http://localhost:8000
+
+## Endpoint
+
+### `POST /analyze_frame/`
+
+Analyzes a single uploaded image frame.  
+
+---
+
+## Headers
+
+- **Response headers**
+  - `People-Count`: integer value (estimated number of people in the frame).
+
+---
+
+## Input Requirements
+
+- **Method:** `POST`  
+- **Content-Type:** `multipart/form-data`  
+- **Form field:** `file` (the uploaded image).  
+- **Supported formats:** `.jpg`, `.jpeg`, `.png`  
+- **Image type:** RGB (will be auto-converted if not)  
+
+---
+
+## Request Body
+
+Form-data with a single image file:
+
+| Key   | Type | Description                        |
+|-------|------|------------------------------------|
+| file  | file | Image frame (PNG/JPG) to analyze. |
+
+---
+
+## Response
+
+- **200 OK**
+  - **Content-Type:** `image/png`
+  - **Body:** Heatmap image (PNG)  
+  - **Headers:** `People-Count: <int>`  
+---
+
+## Example Usage
+
+### cURL
+
+```bash
+curl -X POST "http://localhost:8000/analyze_frame/" \
+  -H "accept: image/png" \
+  -F "file=@frame_10.jpg" \
+  -o output_heatmap.png \
+  -D headers.txt