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, 21 JHUFF_TBL **htblptr, const UINT8 *bits, 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 static const UINT8 val_dc_luminance[] = 62 { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 }; 63 64 static const UINT8 bits_dc_chrominance[17] = 65 { /* 0-base */ 0, 0, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0 }; 66 static const UINT8 val_dc_chrominance[] = 67 { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 }; 68 69 static const UINT8 bits_ac_luminance[17] = 70 { /* 0-base */ 0, 0, 2, 1, 3, 3, 2, 4, 3, 5, 5, 4, 4, 0, 0, 1, 0x7d }; 71 static const UINT8 val_ac_luminance[] = 72 { 0x01, 0x02, 0x03, 0x00, 0x04, 0x11, 0x05, 0x12, 73 0x21, 0x31, 0x41, 0x06, 0x13, 0x51, 0x61, 0x07, 74 0x22, 0x71, 0x14, 0x32, 0x81, 0x91, 0xa1, 0x08, 75 0x23, 0x42, 0xb1, 0xc1, 0x15, 0x52, 0xd1, 0xf0, 76 0x24, 0x33, 0x62, 0x72, 0x82, 0x09, 0x0a, 0x16, 77 0x17, 0x18, 0x19, 0x1a, 0x25, 0x26, 0x27, 0x28, 78 0x29, 0x2a, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 79 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 80 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 81 0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 82 0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 83 0x7a, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 84 0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 85 0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, 86 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 87 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, 0xc4, 0xc5, 88 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4, 89 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xe1, 0xe2, 90 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea, 91 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 92 0xf9, 0xfa }; 93 94 static const UINT8 bits_ac_chrominance[17] = 95 { /* 0-base */ 0, 0, 2, 1, 2, 4, 4, 3, 4, 7, 5, 4, 4, 0, 1, 2, 0x77 }; 96 static const UINT8 val_ac_chrominance[] = 97 { 0x00, 0x01, 0x02, 0x03, 0x11, 0x04, 0x05, 0x21, 98 0x31, 0x06, 0x12, 0x41, 0x51, 0x07, 0x61, 0x71, 99 0x13, 0x22, 0x32, 0x81, 0x08, 0x14, 0x42, 0x91, 100 0xa1, 0xb1, 0xc1, 0x09, 0x23, 0x33, 0x52, 0xf0, 101 0x15, 0x62, 0x72, 0xd1, 0x0a, 0x16, 0x24, 0x34, 102 0xe1, 0x25, 0xf1, 0x17, 0x18, 0x19, 0x1a, 0x26, 103 0x27, 0x28, 0x29, 0x2a, 0x35, 0x36, 0x37, 0x38, 104 0x39, 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 105 0x49, 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 106 0x59, 0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 107 0x69, 0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 108 0x79, 0x7a, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 109 0x88, 0x89, 0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, 110 0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, 111 0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 112 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, 113 0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 114 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 115 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 116 0xea, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 117 0xf9, 0xfa }; 118 119 if (cinfo->is_decompressor) { 120 dc_huff_tbl_ptrs = ((j_decompress_ptr)cinfo)->dc_huff_tbl_ptrs; 121 ac_huff_tbl_ptrs = ((j_decompress_ptr)cinfo)->ac_huff_tbl_ptrs; 122 } else { 123 dc_huff_tbl_ptrs = ((j_compress_ptr)cinfo)->dc_huff_tbl_ptrs; 124 ac_huff_tbl_ptrs = ((j_compress_ptr)cinfo)->ac_huff_tbl_ptrs; 125 } 126 127 add_huff_table(cinfo, &dc_huff_tbl_ptrs[0], bits_dc_luminance, 128 val_dc_luminance); 129 add_huff_table(cinfo, &ac_huff_tbl_ptrs[0], bits_ac_luminance, 130 val_ac_luminance); 131 add_huff_table(cinfo, &dc_huff_tbl_ptrs[1], bits_dc_chrominance, 132 val_dc_chrominance); 133 add_huff_table(cinfo, &ac_huff_tbl_ptrs[1], bits_ac_chrominance, 134 val_ac_chrominance); 135 } 136
