for(i = 0; i < number_of_ferns; i++)
{
    index = 0;
    for(j = 0; j < ntf; j++)
    {
        if (Memory.readUnsignedByte(img + tst.ind1) < Memory.readUnsignedByte(img + tst.ind2)) index++;
        if (j < ntf - 1) index <<= 1;

        tst = tst.next;
    }
    leaves_index[i] = index;
}