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 /*

 * jstdhuff.c

 *

 * This file was part of the Independent JPEG Group's software:

 * Copyright (C) 1991-1998, Thomas G. Lane.

 * libjpeg-turbo Modifications:

 * Copyright (C) 2013, D. R. Commander.

 * For conditions of distribution and use, see the accompanying README file.

 *

 * This file contains routines to set the default Huffman tables, if they are

 * not already set.

 */

 /*

  * Huffman table setup routines

  */

 LOCAL(void)

 add_huff_table (j_common_ptr cinfo,

 		JHUFF_TBL **htblptr, const UINT8 *bits, const UINT8 *val)

 /* Define a Huffman table */

 {

   int nsymbols, len;

   if (*htblptr == NULL)

     *htblptr = jpeg_alloc_huff_table(cinfo);

   else

     return;

   /* Copy the number-of-symbols-of-each-code-length counts */

   MEMCOPY((*htblptr)->bits, bits, SIZEOF((*htblptr)->bits));

   /* Validate the counts.  We do this here mainly so we can copy the right

    * number of symbols from the val[] array, without risking marching off

    * the end of memory.  jchuff.c will do a more thorough test later.

    */

   nsymbols = 0;

   for (len = 1; len <= 16; len++)

     nsymbols += bits[len];

   if (nsymbols < 1 || nsymbols > 256)

     ERREXIT(cinfo, JERR_BAD_HUFF_TABLE);

   MEMCOPY((*htblptr)->huffval, val, nsymbols * SIZEOF(UINT8));

   /* Initialize sent_table FALSE so table will be written to JPEG file. */

   (*htblptr)->sent_table = FALSE;

 }

 LOCAL(void)

 std_huff_tables (j_common_ptr cinfo)

 /* Set up the standard Huffman tables (cf. JPEG standard section K.3) */

 /* IMPORTANT: these are only valid for 8-bit data precision! */

 {

   JHUFF_TBL **dc_huff_tbl_ptrs, **ac_huff_tbl_ptrs;

   static const UINT8 bits_dc_luminance[17] =

     { /* 0-base */ 0, 0, 1, 5, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0 };

   static const UINT8 val_dc_luminance[] =

     { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 };

   static const UINT8 bits_dc_chrominance[17] =

     { /* 0-base */ 0, 0, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0 };

   static const UINT8 val_dc_chrominance[] =

     { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 };

   static const UINT8 bits_ac_luminance[17] =

     { /* 0-base */ 0, 0, 2, 1, 3, 3, 2, 4, 3, 5, 5, 4, 4, 0, 0, 1, 0x7d };

   static const UINT8 val_ac_luminance[] =

     { 0x01, 0x02, 0x03, 0x00, 0x04, 0x11, 0x05, 0x12,

       0x21, 0x31, 0x41, 0x06, 0x13, 0x51, 0x61, 0x07,

       0x22, 0x71, 0x14, 0x32, 0x81, 0x91, 0xa1, 0x08,

       0x23, 0x42, 0xb1, 0xc1, 0x15, 0x52, 0xd1, 0xf0,

       0x24, 0x33, 0x62, 0x72, 0x82, 0x09, 0x0a, 0x16,

       0x17, 0x18, 0x19, 0x1a, 0x25, 0x26, 0x27, 0x28,

       0x29, 0x2a, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39,

       0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49,

       0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59,

       0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69,

       0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79,

       0x7a, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89,

       0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98,

       0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,

       0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6,

       0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, 0xc4, 0xc5,

       0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4,

       0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xe1, 0xe2,

       0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea,

       0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8,

       0xf9, 0xfa };

   static const UINT8 bits_ac_chrominance[17] =

     { /* 0-base */ 0, 0, 2, 1, 2, 4, 4, 3, 4, 7, 5, 4, 4, 0, 1, 2, 0x77 };

   static const UINT8 val_ac_chrominance[] =

     { 0x00, 0x01, 0x02, 0x03, 0x11, 0x04, 0x05, 0x21,

       0x31, 0x06, 0x12, 0x41, 0x51, 0x07, 0x61, 0x71,

       0x13, 0x22, 0x32, 0x81, 0x08, 0x14, 0x42, 0x91,

       0xa1, 0xb1, 0xc1, 0x09, 0x23, 0x33, 0x52, 0xf0,

       0x15, 0x62, 0x72, 0xd1, 0x0a, 0x16, 0x24, 0x34,

       0xe1, 0x25, 0xf1, 0x17, 0x18, 0x19, 0x1a, 0x26,

       0x27, 0x28, 0x29, 0x2a, 0x35, 0x36, 0x37, 0x38,

       0x39, 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48,

       0x49, 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58,

       0x59, 0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,

       0x69, 0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78,

       0x79, 0x7a, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,

       0x88, 0x89, 0x8a, 0x92, 0x93, 0x94, 0x95, 0x96,

       0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5,

       0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4,

       0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3,

       0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2,

       0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda,

       0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9,

       0xea, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8,

       0xf9, 0xfa };

   if (cinfo->is_decompressor) {

     dc_huff_tbl_ptrs = ((j_decompress_ptr)cinfo)->dc_huff_tbl_ptrs;

     ac_huff_tbl_ptrs = ((j_decompress_ptr)cinfo)->ac_huff_tbl_ptrs;

   } else {

     dc_huff_tbl_ptrs = ((j_compress_ptr)cinfo)->dc_huff_tbl_ptrs;

     ac_huff_tbl_ptrs = ((j_compress_ptr)cinfo)->ac_huff_tbl_ptrs;

   }

   add_huff_table(cinfo, &dc_huff_tbl_ptrs[0], bits_dc_luminance,

                  val_dc_luminance);

   add_huff_table(cinfo, &ac_huff_tbl_ptrs[0], bits_ac_luminance,

                  val_ac_luminance);

   add_huff_table(cinfo, &dc_huff_tbl_ptrs[1], bits_dc_chrominance,

                  val_dc_chrominance);

   add_huff_table(cinfo, &ac_huff_tbl_ptrs[1], bits_ac_chrominance,

                  val_ac_chrominance);

 }