insertimg.php

<script>
        window.onload = function(){
        $('.buscarimg').click(function(){
        var destino = "<?php echo base_url('midia/get_imgs') ?>";
        var dados = $("#buscartxt").serialize();
        $.ajax({
            type: "POST",
            url: destino,
            data: dados,
            success: function(retorno){
                $(".retorno").html(retorno);
            }
        });
    });
};
</script>

<div id="modalimg" class="reveal-modal" data-reveal>
    <div class="row collapse">
        <div class="collapse small-7 columns">
            <?php echo form_input(array('name'=>'pesquisarimg', 'class'=>'buscartxt')); ?>
        </div>
        <div class="small-5 columns">
            <?php echo form_button('', 'Buscar', 'class="buscarimg button tiny radius"'); ?>
            <?php echo form_button('', 'Limpar', 'class="limparimg button tiny alert radius"'); ?>
        </div>
    </div>
    <div class="retorno">&nbsp;</div>
    <a class="close-reveal-modal">&#215;</a>
</div>