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hexline.c
Package: celp_3.2a.tar.gz　[view]
Upload User: szhypcb168
Upload Date: 2007-01-06
Package Size: 2187k
Code Size: 3k
Category:

Voice Compress

Development Platform:

Unix_Linux

hexline.c：Code Content
  1. /**************************************************************************
  2. *
  3. * ROUTINE
  4. *               puthex (pack an array of bits into a bitstream)
  5. *
  6. * FUNCTION
  7. *               Input an array of bits and number of bits and the
  8. *               program returns a pointer to a bitstream.
  9. *
  10. * SYNOPSIS
  11. *               subroutine puthex(nb, bits, line)
  12. *
  13. *   formal 
  14. *
  15. *                       data    I/O
  16. *       name            type    type    function
  17. *       -------------------------------------------------------------------
  18. *       nb int i number of bits
  19. *       bits int i bit array
  20. *       line char o packed character bitstream
  21. *
  22. ***************************************************************************
  23. *
  24. * DESCRIPTION
  25. *
  26. *       This program packs an array of bits into a string of hex
  27. *       characters where each character represents 4 bits.  The 
  28. * character stream is nb/4 characters long.
  29. *
  30. ***************************************************************************
  31. *
  32. * CALLED BY
  33. *
  34. *       celp
  35. *
  36. * CALLS
  37. *
  38. *
  39. *
  40. **************************************************************************/
  41. #include <stdio.h>
  42. puthex(nb, bits, line)
  43. int nb, bits[];
  44. char line[];
  45. {
  46.   int i, j;
  47.   
  48.   for (j = 0; j < nb;)
  49.   {
  50.     i = 0;
  51.     do
  52.     {
  53.       i |= (bits[j]&1)<<(3 - j%4);
  54.     } while (++j%4 != 0);
  55.     sprintf(&line[j/4-1],"%X",i);
  56.   }
  57. }  
  59. /**************************************************************************
  60. *
  61. * ROUTINE
  62. *               gethex (unpack a bitstream into an array of bits)
  63. *
  64. * FUNCTION
  65. *               Input a pointer to a bitstream and number of bits,
  66. *               program returns an array of bits.
  67. *
  68. * SYNOPSIS
  69. *               subroutine gethex(nb, bits, line)
  70. *
  71. *   formal 
  72. *
  73. *                       data    I/O
  74. *       name            type    type    function
  75. *       -------------------------------------------------------------------
  76. *       nb int i number of bits
  77. *       bits int o bit array
  78. *       line char i packed character bitstream
  79. *
  80. ***************************************************************************
  81. *
  82. * DESCRIPTION
  83. *
  84. *       This routine takes a string of hex characters and unpacks
  85. *       them into an array of bits, 4 bits for each character.
  86. *
  87. ***************************************************************************
  88. *
  89. * CALLED BY
  90. *
  91. *       celp
  92. *
  93. * CALLS
  94. *
  95. *
  96. *
  97. **************************************************************************/
  98. gethex(nb, bits, line)
  99. int nb, bits[];
  100. char line[];
  101. {
  102.   int i, j;
  103.   
  104.   for (j = 0; j < nb;)
  105.   {
  106.     sscanf(&line[j/4],"%1X",&i);
  107.     do
  108.     {
  109.       bits[j] = ((int) (i & (1 << (3 - j%4))) != 0);
  110.     } while (++j%4 != 0);
  111.   }
  112. }