Titanium - JHEAD ERROR: can't open image even if image is showing

we are writing an application at school with titanium. My part is to create a gallery. Here's the problem, I want to display images using imageAsThumbnail and passing the thumbnailBlob created to the imageView. Whenever the imageAsThumbnail method is used I get this error even if the images are displaying correctly in both android/ios. The error shows in the log just on android for each image. How can I solve this problem?

[ERROR] JHEAD: can't open '/android_asset/Resources/images/1/1/images/1GM_artiglieria.jpg'
[ERROR] JHEAD: can't open '/android_asset/Resources/images/1/1/images/3527_primaguerramondiale.jpg'
[ERROR] JHEAD: can't open '/android_asset/Resources/images/1/1/images/Trincea_alpina.jpg'
[ERROR] JHEAD: can't open '/android_asset/Resources/images/1/1/images/Unknown.jpg'
[ERROR] JHEAD: can't open '/android_asset/Resources/images/1/1/images/alpini.jpg'
[ERROR] JHEAD: can't open '/android_asset/Resources/images/1/1/images/guerra_epocale_prima_guerra_mondiale_mostra__5__1.jpg'
[ERROR] JHEAD: can't open '/android_asset/Resources/images/1/1/images/hqdefault.jpg'
[ERROR] JHEAD: can't open '/android_asset/Resources/images/1/1/images/images.jpeg'
[ERROR] JHEAD: can't open '/android_asset/Resources/images/1/1/images/mondia46.jpg'
[ERROR] JHEAD: can't open '/android_asset/Resources/images/1/1/images/soldato-francese-in-trincea-prima-guerra-mondiale.jpg'
[ERROR] JHEAD: can't open '/android_asset/Resources/images/1/1/images/tesina-prima-guerra.jpg'
[ERROR] JHEAD: can't open '/android_asset/Resources/images/1/1/images/trinceawwi.jpg'
[ERROR] JHEAD: can't open '/android_asset/Resources/images/1/1/images/trincee-russe-nella-foresta-di-sarikamish_h_partb.jpg'

file.js

exports.ApplicationWindow = function ApplicationWindow(a,b) {

var resourcesDirectory = Titanium.Filesystem.resourcesDirectory;
var imageWidth = 300;

/*TOP MENU*/
var numH=require('db').numH();
var numW=require('db').numW();
var distanzaOttimale=require('db').distanzaOttimale();
var h=require('db').defaultElementsHeight();
/*TOP MENU END*/

var dir = Titanium.Filesystem.getFile(resourcesDirectory + 'images/' + a + '/' + b + '/images');
var images = dir.getDirectoryListing();

dir = null;

var scrollView = Ti.UI.createScrollView({
    backgroundColor: '#fff',
    top:h,
    contentWidth: Ti.UI.FILL,
    contentHeight: 'auto',
    height: 'auto',
    scrollType: 'vertical',
    showHorizontalScrollIndicator: 'false',
    showVerticalScrollIndicator: 'true',
    layout: 'horizontal',
    horizontalWrap: true
});

var left, imageFile, thumbnailBlob, thumbnailImage;

for (var i = 0, l = images.length; i<l; ++i) {

    imageFile = Titanium.Filesystem.getFile(resourcesDirectory, 'images/', a, '/', b, '/images/', images[i]);

    imageBlob = imageFile.read();

    thumbnailBlob = imageBlob.imageAsThumbnail(300,0 ,0); //ERROR

    /* 3- [ 30 ] -2- [ 30 ] -2- [ 30 ] -3 */

    // Ternary operator =  condition ? then : else
    left = (i % 3 === 0) ? 3 : 2;

    thumbnailImage = Ti.UI.createImageView({
        top: 10,
        left: left + '%',
        width: '30%',
        image: thumbnailBlob,
        rowID: i,
        opacity: 0
    });

    thumbnailImage.addEventListener('click', onImageClick);

    scrollView.add(thumbnailImage);

    fadeIn(thumbnailImage, 50 * (i + 3));
}

// Aggiungo un piccolo filler… scusa…
scrollView.add(Ti.UI.createView({
    width: Ti.UI.FILL,
    height: 10
}));

function onImageClick(e) {/*
    Ti.API.info('Row ID : ' + e.source.rowID);*/

    var newWin = Ti.UI.createWindow({
        url: 'display.js',
        backgroundColor: '#000',
        zIndex:1,
        page: e.source.rowID,
        a: a,
        b: b
    });

    newWin.open();
}

function fadeIn(view, delay) {
    setTimeout(function () {
        view.animate({
            opacity: 1,
            duration: 200
        });
    }, delay);
}

return scrollView;
};