Update: Fixed the code, you can see it here. 

i deal with a lot of sites where they have a bunch of images listed and sometimes they can end up looking a bit sqashed unless you add a div and set the height and width of it.

this method is fine unless you want to reduce the amount of code, and also it does not work well on some devices.

here is an example of using a image as a background element.

example using image as background

<style>.demo-darken-shared {
	height:300px;
	width:300px;
	display: flex;
	align-items: center;
	justify-content: center;
	color:#FFF;		
	font-size:20px;
	font-weight:bold;
	text-shadow:0px 1px 2px rgba(0,0,0,0.8);
	text-align: center;
}
.demo-darken-img {
	background:url(images/coffee-2608864_1280.jpg) center no-repeat;
	background-size:cover;
}
</style>
<div class='demo-darken-shared demo-darken-img'></div>

as you can see in this demo, you can do it with a div, but if you have your css split up it can be hard to find the images if you have a few of them.

using cover on an image element

usually you cant get an image element to do the same thing as a div background, but now you can! (but not in ie), ie still stretches it but thats usually ok as i dont use ie ;). you can see what is compatable with object-fit here

squished example

here is a normal squished image if i constrain the height and width to 300px.

<style>
.demo-squished-img {
   	height: 300px;
    width: 200px;
}
</style>
<img src='images/coffee-2608864_1280.jpg' class='demo-squished-img'>

object fit img example

and here is the same image with 300px height and 200px width using object-fit: cover;

if you are not using ie, it should look the same as the 1st example div, but this is just on an image element so you dont have to worry about adding the div element with an image background. /yay

<style>
.demo-non-squished-img {
   	height: 300px;
    object-fit: cover;
    width: 200px;
}
</style>
<img src='images/coffee-2608864_1280.jpg' class='demo-non-squished-img'>

basically what this means is you can apply this to your images and it will make them look pretty good, even if the size are contrained which can be very useful.

now we can animate the size of this div using css keyframes no js (cos it looks cool, not really useful), it does give you an idea of what the image will look like if the screen is resized.

<style>
	.animated-img {
		transition: all 0.3s;
		animation: imgwidth 5s infinite;
		object-fit: cover;
	}
	@keyframes imgwidth {
	    0%   {width: 50px; height: 300px;}
	    50%   {width: 100%; height: 300px;}
	    100% {width: 50px; height: 300px;}
	}
</style>
<img src='images/coffee-2608864_1280.jpg' class='animated-img'>

Note: if you stare at this too long you want to have more coffee.