/src/dcmtk/dcmjpeg/libijg12/jclossy.c
Line | Count | Source |
1 | | /* |
2 | | * jclossy.c |
3 | | * |
4 | | * Copyright (C) 1998, 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 the control logic for the lossy JPEG compressor. |
9 | | */ |
10 | | |
11 | | #define JPEG_INTERNALS |
12 | | #include "jinclude12.h" |
13 | | #include "jpeglib12.h" |
14 | | #include "jlossy12.h" |
15 | | |
16 | | |
17 | | /* |
18 | | * Initialize for a processing pass. |
19 | | */ |
20 | | |
21 | | METHODDEF(void) |
22 | | start_pass (j_compress_ptr cinfo, J_BUF_MODE pass_mode) |
23 | | { |
24 | | j_lossy_c_ptr lossyc = (j_lossy_c_ptr) cinfo->codec; |
25 | | |
26 | | (*lossyc->fdct_start_pass) (cinfo); |
27 | | (*lossyc->coef_start_pass) (cinfo, pass_mode); |
28 | | } |
29 | | |
30 | | |
31 | | /* |
32 | | * Initialize the lossy compression codec. |
33 | | * This is called only once, during master selection. |
34 | | */ |
35 | | |
36 | | GLOBAL(void) |
37 | | jinit_lossy_c_codec (j_compress_ptr cinfo) |
38 | 0 | { |
39 | 0 | j_lossy_c_ptr lossyc; |
40 | | |
41 | | /* Create subobject in permanent pool */ |
42 | 0 | lossyc = (j_lossy_c_ptr) |
43 | 0 | (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT, |
44 | 0 | SIZEOF(jpeg_lossy_c_codec)); |
45 | 0 | cinfo->codec = (struct jpeg_c_codec *) lossyc; |
46 | | |
47 | | /* Initialize sub-modules */ |
48 | | |
49 | | /* Forward DCT */ |
50 | 0 | jinit_forward_dct(cinfo); |
51 | | /* Entropy encoding: either Huffman or arithmetic coding. */ |
52 | 0 | if (cinfo->arith_code) { |
53 | 0 | ERREXIT(cinfo, JERR_ARITH_NOTIMPL); |
54 | 0 | } else { |
55 | 0 | if (cinfo->process == JPROC_PROGRESSIVE) { |
56 | 0 | #ifdef C_PROGRESSIVE_SUPPORTED |
57 | 0 | jinit_phuff_encoder(cinfo); |
58 | | #else |
59 | | ERREXIT(cinfo, JERR_NOT_COMPILED); |
60 | | #endif |
61 | 0 | } else |
62 | 0 | jinit_shuff_encoder(cinfo); |
63 | 0 | } |
64 | | |
65 | | /* Need a full-image coefficient buffer in any multi-pass mode. */ |
66 | 0 | jinit_c_coef_controller(cinfo, |
67 | 0 | (boolean) (cinfo->num_scans > 1 || |
68 | 0 | cinfo->optimize_coding)); |
69 | | |
70 | | /* Initialize method pointers. |
71 | | * |
72 | | * Note: entropy_start_pass and entropy_finish_pass are assigned in |
73 | | * jcshuff.c or jcphuff.c and compress_data is assigned in jccoefct.c. |
74 | | */ |
75 | 0 | lossyc->pub.start_pass = start_pass; |
76 | 0 | } |