/* * jcinit.c * * Copyright (C) 1991-1997, Thomas G. Lane. * This file is part of the Independent JPEG Group's software. * For conditions of distribution and use, see the accompanying README file. * * This file contains initialization logic for the JPEG compressor. * This routine is in charge of selecting the modules to be executed and * making an initialization call to each one. * * Logically, this code belongs in jcmaster.c. It's split out because * linking this routine implies linking the entire compression library. * For a transcoding-only application, we want to be able to use jcmaster.c * without linking in the whole library. */ #define JPEG_INTERNALS #include "jinclude.h" #include "jpeglib.h" /* * Master selection of compression modules. * This is done once at the start of processing an image. We determine * which modules will be used and give them appropriate initialization calls. */ GLOBAL(void) jinit_compress_master (j_compress_ptr cinfo) { /* Initialize master control (includes parameter checking/processing) */ jinit_c_master_control(cinfo, FALSE /* full compression */); /* Preprocessing */ if (! cinfo->raw_data_in) { jinit_color_converter(cinfo); jinit_downsampler(cinfo); jinit_c_prep_controller(cinfo, FALSE /* never need full buffer here */); } /* Forward DCT */ jinit_forward_dct(cinfo); /* Entropy encoding: either Huffman or arithmetic coding. */ if (cinfo->arith_code) jinit_arith_encoder(cinfo); else { jinit_huff_encoder(cinfo); } /* Need a full-image coefficient buffer in any multi-pass mode. */ jinit_c_coef_controller(cinfo, (boolean) (cinfo->num_scans > 1 || cinfo->optimize_coding)); jinit_c_main_controller(cinfo, FALSE /* never need full buffer here */); jinit_marker_writer(cinfo); /* We can now tell the memory manager to allocate virtual arrays. */ (*cinfo->mem->realize_virt_arrays) ((j_common_ptr) cinfo); /* Write the datastream header (SOI) immediately. * Frame and scan headers are postponed till later. * This lets application insert special markers after the SOI. */ (*cinfo->marker->write_file_header) (cinfo); }