CSJ2K.j2k.image.invcomptransf.InvCompTransf.calcMixedBitDepths C# (CSharp) Method

        public static int[] calcMixedBitDepths(int[] utdepth, int ttype, int[] tdepth)
        {
            if (utdepth.Length < 3 && ttype != NONE)
            {
                throw new System.ArgumentException();
            }

            if (tdepth == null)
            {
                tdepth = new int[utdepth.Length];
            }

            switch (ttype)
            {

                case NONE:
                    Array.Copy(utdepth, 0, tdepth, 0, utdepth.Length);
                    break;

                case INV_RCT:
                    if (utdepth.Length > 3)
                    {
                        Array.Copy(utdepth, 3, tdepth, 3, utdepth.Length - 3);
                    }
                    // The formulas are:
                    // tdepth[0] = ceil(log2(2^(utdepth[0])+2^utdepth[1]+
                    //                        2^(utdepth[2])))-2+1
                    // tdepth[1] = ceil(log2(2^(utdepth[0])+2^(utdepth[1])-1))+1
                    // tdepth[2] = ceil(log2(2^(utdepth[1])+2^(utdepth[2])-1))+1
                    // The MathUtil.log2(x) function calculates floor(log2(x)), so we
                    // use 'MathUtil.log2(2*x-1)+1', which calculates ceil(log2(x))
                    // for any x>=1, x integer.
                    tdepth[0] = MathUtil.log2((1 << utdepth[0]) + (2 << utdepth[1]) + (1 << utdepth[2]) - 1) - 2 + 1;
                    tdepth[1] = MathUtil.log2((1 << utdepth[2]) + (1 << utdepth[1]) - 1) + 1;
                    tdepth[2] = MathUtil.log2((1 << utdepth[0]) + (1 << utdepth[1]) - 1) + 1;
                    break;

                case INV_ICT:
                    if (utdepth.Length > 3)
                    {
                        Array.Copy(utdepth, 3, tdepth, 3, utdepth.Length - 3);
                    }
                    // The MathUtil.log2(x) function calculates floor(log2(x)), so we
                    // use 'MathUtil.log2(2*x-1)+1', which calculates ceil(log2(x))
                    // for any x>=1, x integer.
                    //UPGRADE_WARNING: Data types in Visual C# might be different.  Verify the accuracy of narrowing conversions. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1042'"
                    tdepth[0] =
                        MathUtil.log2(
                            (int)
                            System.Math.Floor(
                                (1 << utdepth[0]) * 0.299072 + (1 << utdepth[1]) * 0.586914
                                + (1 << utdepth[2]) * 0.114014) - 1) + 1;
                    //UPGRADE_WARNING: Data types in Visual C# might be different.  Verify the accuracy of narrowing conversions. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1042'"
                    tdepth[1] =
                        MathUtil.log2(
                            (int)
                            System.Math.Floor(
                                (1 << utdepth[0]) * 0.168701 + (1 << utdepth[1]) * 0.331299 + (1 << utdepth[2]) * 0.5)
                            - 1) + 1;
                    //UPGRADE_WARNING: Data types in Visual C# might be different.  Verify the accuracy of narrowing conversions. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1042'"
                    tdepth[2] =
                        MathUtil.log2(
                            (int)
                            System.Math.Floor(
                                (1 << utdepth[0]) * 0.5 + (1 << utdepth[1]) * 0.418701 + (1 << utdepth[2]) * 0.081299)
                            - 1) + 1;
                    break;
            }

            return tdepth;
        }