Esempio n. 1
0
        /// <summary>
        /// Return image data
        /// </summary>
        public void HuffDecode(int[, ,] buffer)
        {
            int x, y, tmp;
            int sz = X * Y;

            int[,] Block = new int[8, 8];
            int Cs, Ta, Td, blocks;

            // Read in Scan Header information
            Ls   = dis.ReadInt();
            Ns   = dis.Read();
            Cs   = dis.Read();
            Td   = dis.Read();
            Ta   = Td & 0x0f;
            Td >>= 4;

            Ss   = dis.Read();
            Se   = dis.Read();
            Ah   = dis.Read();
            Al   = Ah & 0x0f;
            Ah >>= 4;

            // Calculate the Number of blocks encoded
            // blocks = X * Y / 64;
            blocks = GetBlockCount() / 6;

            // decode image data and return image data in array
            for (j = 0; j < blocks; j++)
            {
                // Get DC coefficient
                if (Td == 0)
                {
                    hftbl = 0;
                }
                else
                {
                    hftbl = 2;
                }
                tmp   = DECODE();
                Diff  = Receive(tmp);
                ZZ[0] = Pred + Extend(Diff, tmp);
                Pred  = ZZ[0];

                // Get AC coefficients
                if (Ta == 0)
                {
                    hftbl = 1;
                }
                else
                {
                    hftbl = 3;
                }
                Decode_AC_Coefficients();

                // dezigzag and dequantize block
                for (i = 0; i < 64; i++)
                {
                    Block[deZZ[i, 0], deZZ[i, 1]] = ZZ[i] * QNT[0][i];
                }

                // store blocks in buffer
                for (x = 0; x < 8; x++)
                {
                    for (y = 0; y < 8; y++)
                    {
                        buffer[j, x, y] = Block[x, y];
                    }
                }
            }
            dis.Close();
        }