CSJ2K.j2k.wavelet.analysis.ForwWTFull.getNextSubband C# (CSharp) Метод

        private SubbandAn getNextSubband(int c)
        {
            int down = 1;
            int up = 0;
            int direction = down;
            SubbandAn nextsb;

            nextsb = currentSubband[c];
            //If it is the first call to this method
            if (nextsb == null)
            {
                nextsb = getAnSubbandTree(tIdx, c);
                //If there is no decomposition level then send the whole image
                if (!nextsb.isNode)
                {
                    return nextsb;
                }
            }

            //Find the next subband to send
            do
            {
                //If the current subband is null then break
                if (nextsb == null)
                {
                    break;
                }
                //If the current subband is a leaf then select the next leaf to
                //send or go up in the decomposition tree if the leaf was a LL
                //one.
                else if (!nextsb.isNode)
                {
                    switch (nextsb.orientation)
                    {

                        case Subband.WT_ORIENT_HH:
                            nextsb = (SubbandAn) nextsb.Parent.LH;
                            direction = down;
                            break;

                        case Subband.WT_ORIENT_LH:
                            nextsb = (SubbandAn) nextsb.Parent.HL;
                            direction = down;
                            break;

                        case Subband.WT_ORIENT_HL:
                            nextsb = (SubbandAn) nextsb.Parent.LL;
                            direction = down;
                            break;

                        case Subband.WT_ORIENT_LL:
                            nextsb = (SubbandAn) nextsb.Parent;
                            direction = up;
                            break;
                        }
                }
                //Else if the current subband is a node
                else if (nextsb.isNode)
                {
                    //If the direction is down the select the HH subband of the
                    //current node.
                    if (direction == down)
                    {
                        nextsb = (SubbandAn) nextsb.HH;
                    }
                    //Else the direction is up the select the next node to cover
                    //or still go up in the decomposition tree if the node is a LL
                    //subband
                    else if (direction == up)
                    {
                        switch (nextsb.orientation)
                        {

                            case Subband.WT_ORIENT_HH:
                                nextsb = (SubbandAn) nextsb.Parent.LH;
                                direction = down;
                                break;

                            case Subband.WT_ORIENT_LH:
                                nextsb = (SubbandAn) nextsb.Parent.HL;
                                direction = down;
                                break;

                            case Subband.WT_ORIENT_HL:
                                nextsb = (SubbandAn) nextsb.Parent.LL;
                                direction = down;
                                break;

                            case Subband.WT_ORIENT_LL:
                                nextsb = (SubbandAn) nextsb.Parent;
                                direction = up;
                                break;
                            }
                    }
                }

                if (nextsb == null)
                {
                    break;
                }
            }
            while (nextsb.isNode);
            return nextsb;
        }