feat: add demo and README.md

README.md

@@ -1,2 +1,40 @@
 # extractstamp
-extract stamp by opencvjs
+
+Extract stamps from images using OpenCV.js.
+
+## Features
+
+- Extract red stamps from images
+- Support for circular stamp detection and extraction
+- Ability to set the color of the extracted stamp
+
+## Usage Instructions
+
+1. Clone or download this repository to your local machine.
+
+2. Ensure your project includes the following files:
+   - extractStamp.js
+   - opencv.js (can be included via CDN, e.g., https://docs.opencv.org/4.x/opencv.js)
+
+3. Click the "Choose File" button to select an image file containing a stamp.
+
+4. The system will automatically process the image, extract the red stamp, and display the results.
+
+## Main Function Description
+
+- `initOpenCV(callback)`: Initialize OpenCV.js
+- `extractStampWithFile(file, setColor, isCircle)`: Extract stamp from a file
+  - `file`: Image file
+  - `setColor`: Set the color of the extracted stamp (default is red "#ff0000")
+  - `isCircle`: Whether to extract only circular stamps (default is true)
+
+## Example
+```js
+extractStampWithFile(file, '#ff0000', true).then(dstImgList => {
+    console.log('Red stamp extraction successful', dstImgList);
+}).catch(error => {
+    console.error('Error processing image:', error);
+});
+```
+![Original Image](./1.png)
+![Extracted Stamp](./2.png)