htmlでのwebp

<picture>
<source srcset="image_sp.webp" media="(max-width: 768px)" type="image/webp">
<source srcset="image_sp.jpg" media="(max-width: 768px)">
<source srcset="image_pc.webp" type="image/webp">
<img src="image_pc.jpg" alt="サンプル画像">
</picture>