mirror of
https://github.com/mozilla/gecko-dev.git
synced 2024-11-01 06:35:42 +00:00
77 lines
2.4 KiB
C
77 lines
2.4 KiB
C
/*
|
|
* 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) {
|
|
#ifdef C_ARITH_CODING_SUPPORTED
|
|
jinit_arith_encoder(cinfo);
|
|
#else
|
|
ERREXIT(cinfo, JERR_ARITH_NOTIMPL);
|
|
#endif
|
|
} 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,
|
|
(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);
|
|
}
|