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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)
add_huff_table(j_common_ptr cinfo,JHUFF_TBL ** htblptr,const UINT8 * bits,const UINT8 * val)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)
std_huff_tables(j_common_ptr cinfo)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