void KisPixelizeFilter::process(KisPaintDeviceSP device,
                         const QRect& applyRect,
                         const KisFilterConfiguration* configuration,
                         KoUpdater* progressUpdater
                               ) const
{
    QPoint srcTopLeft = applyRect.topLeft();
    Q_ASSERT(device);
    Q_ASSERT(configuration);

    qint32 width = applyRect.width();
    qint32 height = applyRect.height();

    //read the filter configuration values from the KisFilterConfiguration object
    quint32 pixelWidth = configuration->getInt("pixelWidth", 10);
    quint32 pixelHeight = configuration->getInt("pixelHeight", 10);
    if (pixelWidth == 0) pixelWidth = 1;
    if (pixelHeight == 0) pixelHeight = 1;

    qint32 pixelSize = device->pixelSize();
    QVector<qint32> average(pixelSize);

    qint32 count;

    if (progressUpdater) {
        progressUpdater->setRange(0, applyRect.width() * applyRect.height());
    }

    qint32 numberOfPixelsProcessed = 0;

    for (qint32 y = 0; y < height; y += pixelHeight - (y % pixelHeight)) {
        qint32 h = pixelHeight;
        h = qMin(h, height - y);

        for (qint32 x = 0; x < width; x += pixelWidth - (x % pixelWidth)) {
            qint32 w = pixelWidth;
            w = qMin(w, width - x);

            for (qint32 i = 0; i < pixelSize; i++) {
                average[i] = 0;
            }
            count = 0;

            //read
            KisRectConstIteratorSP srcIt = device->createRectConstIteratorNG(srcTopLeft.x() + x, srcTopLeft.y() + y, w, h);
            do {
                for (qint32 i = 0; i < pixelSize; i++) {
                    average[i] += srcIt->oldRawData()[i];
                }
                count++;
            } while (srcIt->nextPixel());

            //average
            if (count > 0) {
                for (qint32 i = 0; i < pixelSize; i++)
                    average[i] /= count;
            }
            //write
            KisRectIteratorSP dstIt = device->createRectIteratorNG(srcTopLeft.x() + x, srcTopLeft.y() + y, w, h);
            do {
                for (int i = 0; i < pixelSize; i++) {
                    dstIt->rawData()[i] = average[i];
                }
            } while (dstIt->nextPixel());
            if (progressUpdater) progressUpdater->setValue(++numberOfPixelsProcessed);
        }
    }
}