Crop Image By Border Using Vanilla JavaScript

A Vanilla JavaScript library that enables you to crop images that have borders around them.

How to use it:

1. Download and load the cropImageByBorder_js.min.js in the document.

<script src="cropImageByBorder_js.min.js"></script>

2. This example App shows how to crop the image you provide.

<input type="file" accept="image/png" onchange="main(this)" />

function main(e) {
  const filename = "cropped.png";
  const file = e.files[0];
  const fr = new FileReader();
  fr.readAsDataURL(file);
  fr.onload = async (f) => {
    const obj = { 
      // border color
      borderColor: "#000000", 
      // based64 data
      base64Data: f.target.result,
      // offset in pixels
      offset: 2,
    };
    const base64 = await CropImageByBorder.getInnerImage(obj).catch((err) =>
      console.log(err)
    );
    const link = document.createElement("a");
    link.download = filename;
    link.href = base64;
    document.body.appendChild(link);
    link.click();
    document.body.removeChild(link);
    delete link;
  };
}