|
0
|
1 |
/*
|
|
|
2 |
* jcinit.c
|
|
|
3 |
*
|
|
|
4 |
* Copyright (C) 1991-1997, Thomas G. Lane.
|
|
|
5 |
* This file is part of the Independent JPEG Group's software.
|
|
|
6 |
* For conditions of distribution and use, see the accompanying README file.
|
|
|
7 |
*
|
|
|
8 |
* This file contains initialization logic for the JPEG compressor.
|
|
|
9 |
* This routine is in charge of selecting the modules to be executed and
|
|
|
10 |
* making an initialization call to each one.
|
|
|
11 |
*
|
|
|
12 |
* Logically, this code belongs in jcmaster.c. It's split out because
|
|
|
13 |
* linking this routine implies linking the entire compression library.
|
|
|
14 |
* For a transcoding-only application, we want to be able to use jcmaster.c
|
|
|
15 |
* without linking in the whole library.
|
|
|
16 |
*/
|
|
|
17 |
|
|
|
18 |
#define JPEG_INTERNALS
|
|
|
19 |
#include "jinclude.h"
|
|
|
20 |
#include "jpeglib.h"
|
|
|
21 |
|
|
|
22 |
|
|
|
23 |
/*
|
|
|
24 |
* Master selection of compression modules.
|
|
|
25 |
* This is done once at the start of processing an image. We determine
|
|
|
26 |
* which modules will be used and give them appropriate initialization calls.
|
|
|
27 |
*/
|
|
|
28 |
|
|
|
29 |
GLOBAL(void)
|
|
|
30 |
jinit_compress_master (j_compress_ptr cinfo)
|
|
|
31 |
{
|
|
|
32 |
/* Initialize master control (includes parameter checking/processing) */
|
|
|
33 |
jinit_c_master_control(cinfo, FALSE /* full compression */);
|
|
|
34 |
|
|
|
35 |
/* Preprocessing */
|
|
|
36 |
if (! cinfo->raw_data_in) {
|
|
|
37 |
jinit_color_converter(cinfo);
|
|
|
38 |
jinit_downsampler(cinfo);
|
|
|
39 |
jinit_c_prep_controller(cinfo, FALSE /* never need full buffer here */);
|
|
|
40 |
}
|
|
|
41 |
/* Forward DCT */
|
|
|
42 |
jinit_forward_dct(cinfo);
|
|
|
43 |
/* Entropy encoding: either Huffman or arithmetic coding. */
|
|
|
44 |
if (cinfo->arith_code) {
|
|
|
45 |
ERREXIT(cinfo, JERR_ARITH_NOTIMPL);
|
|
|
46 |
} else {
|
|
|
47 |
if (cinfo->progressive_mode) {
|
|
|
48 |
#ifdef C_PROGRESSIVE_SUPPORTED
|
|
|
49 |
jinit_phuff_encoder(cinfo);
|
|
|
50 |
#else
|
|
|
51 |
ERREXIT(cinfo, JERR_NOT_COMPILED);
|
|
|
52 |
#endif
|
|
|
53 |
} else
|
|
|
54 |
jinit_huff_encoder(cinfo);
|
|
|
55 |
}
|
|
|
56 |
|
|
|
57 |
/* Need a full-image coefficient buffer in any multi-pass mode. */
|
|
|
58 |
jinit_c_coef_controller(cinfo,
|
|
|
59 |
(boolean) (cinfo->num_scans > 1 || cinfo->optimize_coding));
|
|
|
60 |
jinit_c_main_controller(cinfo, FALSE /* never need full buffer here */);
|
|
|
61 |
|
|
|
62 |
jinit_marker_writer(cinfo);
|
|
|
63 |
|
|
|
64 |
/* We can now tell the memory manager to allocate virtual arrays. */
|
|
|
65 |
(*cinfo->mem->realize_virt_arrays) ((j_common_ptr) cinfo);
|
|
|
66 |
|
|
|
67 |
/* Write the datastream header (SOI) immediately.
|
|
|
68 |
* Frame and scan headers are postponed till later.
|
|
|
69 |
* This lets application insert special markers after the SOI.
|
|
|
70 |
*/
|
|
|
71 |
(*cinfo->marker->write_file_header) (cinfo);
|
|
|
72 |
}
|