1 | /* |
2 | * jstdhuff.c |
3 | * |
4 | * This file was part of the Independent JPEG Group's software: |
5 | * Copyright (C) 1991-1998, Thomas G. Lane. |
6 | * libjpeg-turbo Modifications: |
7 | * Copyright (C) 2013, D. R. Commander. |
8 | * For conditions of distribution and use, see the accompanying README.ijg |
9 | * file. |
10 | * |
11 | * This file contains routines to set the default Huffman tables, if they are |
12 | * not already set. |
13 | */ |
14 | |
15 | /* |
16 | * Huffman table setup routines |
17 | */ |
18 | |
19 | LOCAL(void) |
20 | add_huff_table(j_common_ptr cinfo, JHUFF_TBL **htblptr, const UINT8 *bits, |
21 | const UINT8 *val) |
22 | /* Define a Huffman table */ |
23 | { |
24 | int nsymbols, len; |
25 | |
26 | if (*htblptr == NULL) |
27 | *htblptr = jpeg_alloc_huff_table(cinfo); |
28 | else |
29 | return; |
30 | |
31 | /* Copy the number-of-symbols-of-each-code-length counts */ |
32 | MEMCOPY((*htblptr)->bits, bits, sizeof((*htblptr)->bits)); |
33 | |
34 | /* Validate the counts. We do this here mainly so we can copy the right |
35 | * number of symbols from the val[] array, without risking marching off |
36 | * the end of memory. jchuff.c will do a more thorough test later. |
37 | */ |
38 | nsymbols = 0; |
39 | for (len = 1; len <= 16; len++) |
40 | nsymbols += bits[len]; |
41 | if (nsymbols < 1 || nsymbols > 256) |
42 | ERREXIT(cinfo, JERR_BAD_HUFF_TABLE); |
43 | |
44 | MEMCOPY((*htblptr)->huffval, val, nsymbols * sizeof(UINT8)); |
45 | MEMZERO(&((*htblptr)->huffval[nsymbols]), (256 - nsymbols) * sizeof(UINT8)); |
46 | |
47 | /* Initialize sent_table FALSE so table will be written to JPEG file. */ |
48 | (*htblptr)->sent_table = FALSE; |
49 | } |
50 | |
51 | |
52 | LOCAL(void) |
53 | std_huff_tables(j_common_ptr cinfo) |
54 | /* Set up the standard Huffman tables (cf. JPEG standard section K.3) */ |
55 | /* IMPORTANT: these are only valid for 8-bit data precision! */ |
56 | { |
57 | JHUFF_TBL **dc_huff_tbl_ptrs, **ac_huff_tbl_ptrs; |
58 | |
59 | static const UINT8 bits_dc_luminance[17] = { |
60 | /* 0-base */ 0, 0, 1, 5, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0 |
61 | }; |
62 | static const UINT8 val_dc_luminance[] = { |
63 | 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 |
64 | }; |
65 | |
66 | static const UINT8 bits_dc_chrominance[17] = { |
67 | /* 0-base */ 0, 0, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0 |
68 | }; |
69 | static const UINT8 val_dc_chrominance[] = { |
70 | 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 |
71 | }; |
72 | |
73 | static const UINT8 bits_ac_luminance[17] = { |
74 | /* 0-base */ 0, 0, 2, 1, 3, 3, 2, 4, 3, 5, 5, 4, 4, 0, 0, 1, 0x7d |
75 | }; |
76 | static const UINT8 val_ac_luminance[] = { |
77 | 0x01, 0x02, 0x03, 0x00, 0x04, 0x11, 0x05, 0x12, |
78 | 0x21, 0x31, 0x41, 0x06, 0x13, 0x51, 0x61, 0x07, |
79 | 0x22, 0x71, 0x14, 0x32, 0x81, 0x91, 0xa1, 0x08, |
80 | 0x23, 0x42, 0xb1, 0xc1, 0x15, 0x52, 0xd1, 0xf0, |
81 | 0x24, 0x33, 0x62, 0x72, 0x82, 0x09, 0x0a, 0x16, |
82 | 0x17, 0x18, 0x19, 0x1a, 0x25, 0x26, 0x27, 0x28, |
83 | 0x29, 0x2a, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, |
84 | 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, |
85 | 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, |
86 | 0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, |
87 | 0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, |
88 | 0x7a, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, |
89 | 0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, |
90 | 0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, |
91 | 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, |
92 | 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, 0xc4, 0xc5, |
93 | 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4, |
94 | 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xe1, 0xe2, |
95 | 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea, |
96 | 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, |
97 | 0xf9, 0xfa |
98 | }; |
99 | |
100 | static const UINT8 bits_ac_chrominance[17] = { |
101 | /* 0-base */ 0, 0, 2, 1, 2, 4, 4, 3, 4, 7, 5, 4, 4, 0, 1, 2, 0x77 |
102 | }; |
103 | static const UINT8 val_ac_chrominance[] = { |
104 | 0x00, 0x01, 0x02, 0x03, 0x11, 0x04, 0x05, 0x21, |
105 | 0x31, 0x06, 0x12, 0x41, 0x51, 0x07, 0x61, 0x71, |
106 | 0x13, 0x22, 0x32, 0x81, 0x08, 0x14, 0x42, 0x91, |
107 | 0xa1, 0xb1, 0xc1, 0x09, 0x23, 0x33, 0x52, 0xf0, |
108 | 0x15, 0x62, 0x72, 0xd1, 0x0a, 0x16, 0x24, 0x34, |
109 | 0xe1, 0x25, 0xf1, 0x17, 0x18, 0x19, 0x1a, 0x26, |
110 | 0x27, 0x28, 0x29, 0x2a, 0x35, 0x36, 0x37, 0x38, |
111 | 0x39, 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, |
112 | 0x49, 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, |
113 | 0x59, 0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, |
114 | 0x69, 0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, |
115 | 0x79, 0x7a, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, |
116 | 0x88, 0x89, 0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, |
117 | 0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, |
118 | 0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, |
119 | 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, |
120 | 0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, |
121 | 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, |
122 | 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, |
123 | 0xea, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, |
124 | 0xf9, 0xfa |
125 | }; |
126 | |
127 | if (cinfo->is_decompressor) { |
128 | dc_huff_tbl_ptrs = ((j_decompress_ptr)cinfo)->dc_huff_tbl_ptrs; |
129 | ac_huff_tbl_ptrs = ((j_decompress_ptr)cinfo)->ac_huff_tbl_ptrs; |
130 | } else { |
131 | dc_huff_tbl_ptrs = ((j_compress_ptr)cinfo)->dc_huff_tbl_ptrs; |
132 | ac_huff_tbl_ptrs = ((j_compress_ptr)cinfo)->ac_huff_tbl_ptrs; |
133 | } |
134 | |
135 | add_huff_table(cinfo, &dc_huff_tbl_ptrs[0], bits_dc_luminance, |
136 | val_dc_luminance); |
137 | add_huff_table(cinfo, &ac_huff_tbl_ptrs[0], bits_ac_luminance, |
138 | val_ac_luminance); |
139 | add_huff_table(cinfo, &dc_huff_tbl_ptrs[1], bits_dc_chrominance, |
140 | val_dc_chrominance); |
141 | add_huff_table(cinfo, &ac_huff_tbl_ptrs[1], bits_ac_chrominance, |
142 | val_ac_chrominance); |
143 | } |
144 | |