JSLink-OWA-Thumbnails.js

// Source: http://josharepoint.com/2014/11/13/create-thumbnails-view-using-client-side-rendering-and-owa-in-sharepoint-2013/
(function () {
    ExecuteOrDelayUntilScriptLoaded(_registerSliderViewTemplate, 'clienttemplates.js');
})();

function _registerSliderViewTemplate() {
    // Initialize the variable that store the objects. 
    var overrideCtx = {};
    overrideCtx.Templates = {};
    overrideCtx.Templates.Header = HeaderOverrideFun;
    overrideCtx.Templates.Item = ItemRenderCustom;

    overrideCtx.BaseViewID = 1;
    overrideCtx.ListTemplateType = 101;

    // Register the template overrides. 
    SPClientTemplates.TemplateManager.RegisterTemplateOverrides(overrideCtx);
}


function HeaderOverrideFun(ctx) {
    var finalHeaderHtml = '';
    finalHeaderHtml += '<style type="text/css">';
    finalHeaderHtml += '    .ms-listviewtable thead tr { table-layout:fixed; display:table-row-group; float:left; } ';
    finalHeaderHtml += '    .tbTitle { margin-bottom: 5px; margin-top: 10px; } ';
    finalHeaderHtml += '    .tbTrItem { table-layout:fixed; display:table-row-group; float:left; width: 315px; height: 300px !important; } ';
    finalHeaderHtml += '    .tbTdItem { width: 300px; } ';
    finalHeaderHtml += '</style>';
    finalHeaderHtml += RenderHeaderTemplate(ctx);

    return finalHeaderHtml;
}

function ItemRenderCustom(renderCtx) {
	var listItem = renderCtx.CurrentItem;
	var listSchema = renderCtx.ListSchema;
	var idx = renderCtx.CurrentItemIdx;
	var cssClass = idx % 2 == 1 ? "ms-alternating " : "";

	if (FHasRowHoverBehavior(renderCtx)) {
		cssClass += " ms-itmHoverEnabled ";
	}
	var ret = [];

	ret.push('<tr class="tbTrItem ');
	ret.push('" iid="');
	var iid = GenerateIID(renderCtx);
	//var idString = ctx.ctxId + ',' + listItem.ID + ',' + listItem.FSObjType;

	ret.push(iid);
	ret.push('" id="');
	ret.push(iid);
	ret.push('">');

	var fields = listSchema ? listSchema.Field : null;


	var owaUrl = listItem.ServerRedirectedEmbedUrl;
	var newOwaUrl = "";
	var newOwaFullPageUrl = "";
	if (owaUrl != null) 
	{
		newOwaUrl = owaUrl.replace('WopiFrame', 'WopiFrame2');
		newOwaFullPageUrl = newOwaUrl.replace('interactivepreview', 'view');
	}

	var titleText = listItem.Title;
	if (titleText == '') {
		titleText = listItem.FileLeafRef;
	}

	//EditListItems permissions
	//if (HasRights(0x0, 0x800))
	var showedit = true;
	if (ctx.CurrentItem.PermMask == '0xb008431061') {
		showedit = false;
	}

	ret.push('<td colspan="');
	ret.push(fields.length + 2);
	ret.push('" class="tbTdItem" >');
	ret.push('<div class="tbTitle"><a href="');
	ret.push(newOwaFullPageUrl);
	ret.push('" target="_blank" >');
	ret.push(titleText);
	ret.push('</a></div>');
	ret.push('<iframe src="');
	ret.push(newOwaUrl);
	ret.push('" width="300" height="250"></iframe>');
	ret.push('</td>');

	ret.push('</tr>');
	return ret.join('');
};