Rails 4: crop image from URL and preserve ratio

Question

In my Rails 4 app, I use the MetaInspector gem to scrap images from a link provided by the user.

This way, I am capable of doing something like this in my views:

<%= image_tag(@link.images.best) %>

and it works pretty well.

Now, I would like to resize / crop these images to a particular dimension of 450x246px so, I tried to do this:

<%= image_tag(@link.images.best, size: "450x246") %>

but this solution does not preserve the initial ratio of the images.

I am fine with "cutting" the images as long as we do not distort them.

I found this solution but it does not fit my use case: I do not want to store the images in my database, I simply want to pull them from a URL and display them in my views.

How can I resize / crop my images "on the fly" directly in my views?

Answer 1

Here is what I ended up doing:

#HTML
<div id="container" style="background-image:url(<%= @link.images.best %>);">
</div>

#CSS
#container {
    overflow: hidden;
    width: 445px;
    height: 246px;
    background-position: 50% 50%;
    background-repeat: no-repeat;
    background-size: cover;
    background-color: transparent;
}

This works really well, no matter the width or the height of the original image.