BitMiracle.LibJpeg.Classic.Internal.jpeg_comp_master.prepare_for_main_pass C# (CSharp) Method

        private void prepare_for_main_pass()
        {
            /* Initial pass: will collect input data, and do either Huffman
            * optimization or data output for the first scan.
            */
            select_scan_parameters();
            per_scan_setup();

            if (!m_cinfo.m_raw_data_in)
            {
                m_cinfo.m_cconvert.start_pass();
                m_cinfo.m_prep.start_pass(J_BUF_MODE.JBUF_PASS_THRU);
            }

            m_cinfo.m_fdct.start_pass();
            m_cinfo.m_entropy.start_pass(m_cinfo.m_optimize_coding);
            m_cinfo.m_coef.start_pass((m_total_passes > 1 ? J_BUF_MODE.JBUF_SAVE_AND_PASS : J_BUF_MODE.JBUF_PASS_THRU));
            m_cinfo.m_main.start_pass(J_BUF_MODE.JBUF_PASS_THRU);

            if (m_cinfo.m_optimize_coding)
            {
                /* No immediate data output; postpone writing frame/scan headers */
                m_call_pass_startup = false;
            }
            else
            {
                /* Will write frame/scan headers at first jpeg_write_scanlines call */
                m_call_pass_startup = true;
            }
        }