<!DOCTYPE html>
<html>
<body>

Select a file to upload:
<input type="file" id="myFile" size="50">

<p>Click the button below to specify that the server should only accept audio and video files in the file upload.</p>

<button onclick="myFunction()">Change accepted file types</button>

<p id="demo"></p>

<script>
function myFunction() {
    document.getElementById("myFile").accept = "audio/*,video/*";
    document.getElementById("demo").innerHTML = "The accepted file types have been set. Click 'Choose File' to see the effect.";
}
</script>

</body>
</html>