How can I resize the extended image of an article

Hi,
I have inStyle and I would use extended article image in the articles.
The image is resized to fill the screen width but it is too height.
It is possibile to have the extended image that fill the monitor width but is cropped at certain height?

Thanks

Hi,
I have to see it to say more,
but probably it's possible using max-height value for images, for example 800px.

And the easy one --- don't add so big image , people don't want to wait 60 seconds before your image/picture will be loaded.
I hope that you don't add images strictly from camera.