Bootstrap File Input Plugin

Has anyone used this Bootstrap File Input Plugin with PHP? That is, doing image insert in the bank? I'm having trouble getting the files from the plugin, not the input file, to do the persistence.

Code

<form enctype="multipart/form-data" method="post" id="imagensSitio">
     <input id="file-0a" class="file" type="file" name="img[]" multiple="true" >
     <input type="submit" name="salvar" value="Salvar" class="btn btn-primary">
</form>

<script type="text/javascript">
jQuery(document).ready(function() { 
    jQuery('#imagensSitio').submit(function(){
        var dados = jQuery( this ).serialize();

        $.ajax({
            url: "crud/insere.php", // Url to which the request is sending
            type: "POST",             // Type of request to be send, called as method
            data: new FormData(this), // Data sent to server, a set of key/value pairs (i.e. form fields and values)
            contentType: false,       // The content type used when sending data to the server.
            cache: false,             // To unable request pages to be cached
            processData:false,        // To send DOMDocument or non processed data file it is set to false
            success: function(data)   // A function to be called if request succeeds
            {
                location.reload();
            }
        });
    });
});

$("#file-0a").fileinput({
    uploadUrl: "crud/insere.php",
    uploadAsync: false,
    minFileCount: 1,
    maxFileCount: 10,
    showUpload:true,
    showRemove:true
});
</script>

Insere.php

 include("../../../resources/conexao/conexao.php");
require ("../../../resources/wideImage/WideImage.php"); 

$nomeImg = $_FILES['img']['name'];
$nomeTmp = $_FILES['img']['tmp_name'];  

$extensao = array(".jpeg", ".jpg", ".png");

$dir_imagem = '../imagens/sitio/';

for($i = 0; $i < count($nomeTmp); $i++) {

    $extensao_img = strtolower(substr($nomeImg[$i],-4));

    if(in_array($extensao_img, $extensao)) {

        $novo_nome_imagem = date("Y.m.d-H.i.s") ."-". $i . $extensao_img;

        $imagem = WideImage::load($nomeTmp[$i]);
        $imagem = $imagem -> resize(770, 550, 'outside');

        if ($extensao_img == ".jpg" || $extensao_img == ".jpeg"){
            $imagem -> saveToFile($dir_imagem.$novo_nome_imagem, 85);
        } else if ($extensao_img == ".png") {
            $imagem -> saveToFile($dir_imagem.$novo_nome_imagem, 9);
        }

        $insert = "INSERT INTO sitio(imagem) VALUES ('$novo_nome_imagem')"; 
        $conexao = conexao();
        $PDO = $conexao->prepare($insert);
        $PDO -> execute();
        $conexao = null;                
    } 
}

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