diff options
Diffstat (limited to 'src/jpeg-6/jcinit.c')
-rw-r--r-- | src/jpeg-6/jcinit.c | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/src/jpeg-6/jcinit.c b/src/jpeg-6/jcinit.c new file mode 100644 index 0000000..2cc82b2 --- /dev/null +++ b/src/jpeg-6/jcinit.c @@ -0,0 +1,72 @@ +/* + * jcinit.c + * + * Copyright (C) 1991-1995, 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) { + ERREXIT(cinfo, JERR_ARITH_NOTIMPL); + } else { + if (cinfo->progressive_mode) { +#ifdef C_PROGRESSIVE_SUPPORTED + jinit_phuff_encoder(cinfo); +#else + ERREXIT(cinfo, JERR_NOT_COMPILED); +#endif + } else + jinit_huff_encoder(cinfo); + } + + /* Need a full-image coefficient buffer in any multi-pass mode. */ + jinit_c_coef_controller(cinfo, + (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); +} |