BitMiracle.LibJpeg.Classic.Internal.JpegUtils.jcopy_sample_rows C# (CSharp) Method

        public static void jcopy_sample_rows(ComponentBuffer input_array, int source_row, ComponentBuffer output_array, int dest_row, int num_rows, int num_cols)
        {
            for (int row = 0; row < num_rows; row++)
                Buffer.BlockCopy(input_array[source_row + row], 0, output_array[dest_row + row], 0, num_cols);
        }

        /// <summary>
        /// This version handles any integral sampling ratios.
        /// This is not used for typical JPEG files, so it need not be fast.
        /// Nor, for that matter, is it particularly accurate: the algorithm is
        /// simple replication of the input pixel onto the corresponding output
        /// pixels.  The hi-falutin sampling literature refers to this as a
        /// "box filter".  A box filter tends to introduce visible artifacts,
        /// so if you are actually going to use 3:1 or 4:1 sampling ratios
        /// you would be well advised to improve this code.
        /// </summary>
        private void int_upsample(ref ComponentBuffer input_data)
        {
            ComponentBuffer output_data = m_color_buf[m_currentComponent];
            int             h_expand    = m_h_expand[m_currentComponent];
            int             v_expand    = m_v_expand[m_currentComponent];

            int inrow  = 0;
            int outrow = 0;

            while (outrow < m_cinfo.m_max_v_samp_factor)
            {
                /* Generate one output row with proper horizontal expansion */
                int row = m_upsampleRowOffset + inrow;
                for (int col = 0; col < m_cinfo.m_output_width; col++)
                {
                    byte invalue  = input_data[row][col]; /* don't need GETJSAMPLE() here */
                    int  outIndex = 0;
                    for (int h = h_expand; h > 0; h--)
                    {
                        output_data[outrow][outIndex] = invalue;
                        outIndex++;
                    }
                }

                /* Generate any additional output rows by duplicating the first one */
                if (v_expand > 1)
                {
                    JpegUtils.jcopy_sample_rows(output_data, outrow, output_data,
                                                outrow + 1, v_expand - 1, m_cinfo.m_output_width);
                }

                inrow++;
                outrow += v_expand;
            }
        }