How to decode base64 text to binary file?

I am converting binary file’s buffer to base64 text before storing to mongodb. I am using multer to get image alongside with with other field. I am sending those data in FormData and the back end is

app.post('/image', multer().single('image'), (req, res) => {
    const image = Buffer.from(req.file.buffer).toString('base64')
    database.collection('images').insertOne({image})
}

Now, how do I decode this base64 text to binary image?

I tried this in the front end after getting the json from the back end

URL.createObjectURL(new Blob([window.atob(data.image)]))

But I think the binary file is corrupted.