It's a bit late but I just had the same problem and finally solved it with the help of another stackoverflow post (https://stackoverflow.com/a/29103071).
img {
object-fit: cover;
width: 50px;
height: 100px;
}
Hope this still helps somebody.
Ps: Also works together with max-height, max-width, min-width and min-height css properties. It's espacially handy with using lenght units like 100% or 100vh/100vw to fill the container or the whole browser window.