So I want an img to be displayed
You could use a div with a background image instead and this CSS3 property:
background-size: contain
You can check out an example on:
https://developer.mozilla.org/en-US/docs/Web/Guide/CSS/Scaling_background_images#contain
To quote Mozilla:
The contain value specifies that regardless of the size of the containing box, the background image should be scaled so that each side is as large as possible while not exceeding the length of the corresponding side of the container.
However, keep in mind that your image will be upscaled if the div is larger than your original image.