Apply soft edges to image using CSS

You can try that: fiddle

<div class="shadow">
        <img src="http://via.placeholder.com/350x150/" />
</div>

And CSS.

shadow
{
    display:block;
    position:relative;
}

img {
    width: 100%;
    height: 100%;
}

.shadow:before
{
    display:block;
    content:'';
    position:absolute;
    width:100%;
    height:100%;
    -moz-box-shadow:inset 0px 0px 6px 6px rgba(255,255,255,1);
    -webkit-box-shadow:inset 0px 0px 6px 6px rgba(255,255,255,1);
    box-shadow:inset 0px 0px 6px 6px rgba(255,255,255,1);
}

You can try something like this:

JSFiddle Example

HTML :

<div id="image-container"><div>

CSS:

#image-container {
background: url(http://pic2.ooopic.com/11/26/30/31b1OOOPIC48.jpg) left top no-repeat;
box-shadow: 25px 25px 50px 0 white inset, -25px -25px 50px 0 white inset; 
width: 300px;
height: 300px;
}