Shrink image in usercontrols

Question

I have asp.net user control that has datalist load images. But it is not working for me.

<td class="billboard-itemPicture">
<asp:Image ID="Image1" runat="server" class="billboard-picture" ImageUrl='<%#Eval("UserImage") %>' Width="100px" Height="100px" />

<script type="text/javascript"  >
$(document).ready(function() {

    $('.billboard-itemPicture img').each(function() {
        var maxWidth = 100; // Max width for the image
        var maxHeight = 100;    // Max height for the image
        var ratio = 0;  // Used for aspect ratio
        var width = $(this).width();    // Current image width
        var height = $(this).height();  // Current image height

        // Check if the current width is larger than the max
        if (width > maxWidth) {
            ratio = maxWidth / width;   // get ratio for scaling image
            $(this).css("width", maxWidth); // Set new width
            $(this).css("height", height * ratio);  // Scale height based on ratio
            height = height * ratio;    // Reset height to match scaled image
            width = width * ratio;    // Reset width to match scaled image
        }

        // Check if current height is larger than max
        if (height > maxHeight) {
            ratio = maxHeight / height; // get ratio for scaling image
            $(this).css("height", maxHeight);   // Set new height
            $(this).css("width", width * ratio);    // Scale width based on ratio
            width = width * ratio;    // Reset width to match scaled image
        }
    });
});