media/libjpeg/jstdhuff.c

   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, 2022, 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   memcpy((*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   memcpy((*htblptr)->huffval, val, nsymbols * sizeof(UINT8));
  45   memset(&((*htblptr)->huffval[nsymbols]), 0,
  46          (256 - nsymbols) * sizeof(UINT8));
  47
  48   /* Initialize sent_table FALSE so table will be written to JPEG file. */
  49   (*htblptr)->sent_table = FALSE;
  50 }
  51
  52
  53 LOCAL(void)
  54 std_huff_tables(j_common_ptr cinfo)
  55 /* Set up the standard Huffman tables (cf. JPEG standard section K.3) */
  56 /* IMPORTANT: these are only valid for 8-bit data precision! */
  57 {
  58   JHUFF_TBL **dc_huff_tbl_ptrs, **ac_huff_tbl_ptrs;
  59
  60   static const UINT8 bits_dc_luminance[17] = {
  61     /* 0-base */ 0, 0, 1, 5, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0
  62   };
  63   static const UINT8 val_dc_luminance[] = {
  64     0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
  65   };
  66
  67   static const UINT8 bits_dc_chrominance[17] = {
  68     /* 0-base */ 0, 0, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0
  69   };
  70   static const UINT8 val_dc_chrominance[] = {
  71     0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
  72   };
  73
  74   static const UINT8 bits_ac_luminance[17] = {
  75     /* 0-base */ 0, 0, 2, 1, 3, 3, 2, 4, 3, 5, 5, 4, 4, 0, 0, 1, 0x7d
  76   };
  77   static const UINT8 val_ac_luminance[] = {
  78     0x01, 0x02, 0x03, 0x00, 0x04, 0x11, 0x05, 0x12,
  79     0x21, 0x31, 0x41, 0x06, 0x13, 0x51, 0x61, 0x07,
  80     0x22, 0x71, 0x14, 0x32, 0x81, 0x91, 0xa1, 0x08,
  81     0x23, 0x42, 0xb1, 0xc1, 0x15, 0x52, 0xd1, 0xf0,
  82     0x24, 0x33, 0x62, 0x72, 0x82, 0x09, 0x0a, 0x16,
  83     0x17, 0x18, 0x19, 0x1a, 0x25, 0x26, 0x27, 0x28,
  84     0x29, 0x2a, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39,
  85     0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49,
  86     0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59,
  87     0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69,
  88     0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79,
  89     0x7a, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89,
  90     0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98,
  91     0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,
  92     0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6,
  93     0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, 0xc4, 0xc5,
  94     0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4,
  95     0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xe1, 0xe2,
  96     0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea,
  97     0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8,
  98     0xf9, 0xfa
  99   };
 100
 101   static const UINT8 bits_ac_chrominance[17] = {
 102     /* 0-base */ 0, 0, 2, 1, 2, 4, 4, 3, 4, 7, 5, 4, 4, 0, 1, 2, 0x77
 103   };
 104   static const UINT8 val_ac_chrominance[] = {
 105     0x00, 0x01, 0x02, 0x03, 0x11, 0x04, 0x05, 0x21,
 106     0x31, 0x06, 0x12, 0x41, 0x51, 0x07, 0x61, 0x71,
 107     0x13, 0x22, 0x32, 0x81, 0x08, 0x14, 0x42, 0x91,
 108     0xa1, 0xb1, 0xc1, 0x09, 0x23, 0x33, 0x52, 0xf0,
 109     0x15, 0x62, 0x72, 0xd1, 0x0a, 0x16, 0x24, 0x34,
 110     0xe1, 0x25, 0xf1, 0x17, 0x18, 0x19, 0x1a, 0x26,
 111     0x27, 0x28, 0x29, 0x2a, 0x35, 0x36, 0x37, 0x38,
 112     0x39, 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48,
 113     0x49, 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58,
 114     0x59, 0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,
 115     0x69, 0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78,
 116     0x79, 0x7a, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
 117     0x88, 0x89, 0x8a, 0x92, 0x93, 0x94, 0x95, 0x96,
 118     0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5,
 119     0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4,
 120     0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3,
 121     0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2,
 122     0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda,
 123     0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9,
 124     0xea, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8,
 125     0xf9, 0xfa
 126   };
 127
 128   if (cinfo->is_decompressor) {
 129     dc_huff_tbl_ptrs = ((j_decompress_ptr)cinfo)->dc_huff_tbl_ptrs;
 130     ac_huff_tbl_ptrs = ((j_decompress_ptr)cinfo)->ac_huff_tbl_ptrs;
 131   } else {
 132     dc_huff_tbl_ptrs = ((j_compress_ptr)cinfo)->dc_huff_tbl_ptrs;
 133     ac_huff_tbl_ptrs = ((j_compress_ptr)cinfo)->ac_huff_tbl_ptrs;
 134   }
 135
 136   add_huff_table(cinfo, &dc_huff_tbl_ptrs[0], bits_dc_luminance,
 137                  val_dc_luminance);
 138   add_huff_table(cinfo, &ac_huff_tbl_ptrs[0], bits_ac_luminance,
 139                  val_ac_luminance);
 140   add_huff_table(cinfo, &dc_huff_tbl_ptrs[1], bits_dc_chrominance,
 141                  val_dc_chrominance);
 142   add_huff_table(cinfo, &ac_huff_tbl_ptrs[1], bits_ac_chrominance,
 143                  val_ac_chrominance);
 144 }