stretch the image in HTML background

Try as
use
Streched backgroungd image

<img src="myimg.jpg" width="100%" height="100%" alt="ImageShow">

</img>

If you want to stretch an image depending on how wide it's container is, you can do so with a relative width in your width attribute.

<img src="image.jpg" width="100%" height="150">
<img src="image.jpg" width="50%" height="150">

But it stretches small images so much that we are unable to figure out actual image.