bio.h 3.9 KB

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  1. /*
  2. * Copyright (c) 2002-2007, Communications and Remote Sensing Laboratory, Universite catholique de Louvain (UCL), Belgium
  3. * Copyright (c) 2002-2007, Professor Benoit Macq
  4. * Copyright (c) 2001-2003, David Janssens
  5. * Copyright (c) 2002-2003, Yannick Verschueren
  6. * Copyright (c) 2003-2007, Francois-Olivier Devaux and Antonin Descampe
  7. * Copyright (c) 2005, Herve Drolon, FreeImage Team
  8. * All rights reserved.
  9. *
  10. * Redistribution and use in source and binary forms, with or without
  11. * modification, are permitted provided that the following conditions
  12. * are met:
  13. * 1. Redistributions of source code must retain the above copyright
  14. * notice, this list of conditions and the following disclaimer.
  15. * 2. Redistributions in binary form must reproduce the above copyright
  16. * notice, this list of conditions and the following disclaimer in the
  17. * documentation and/or other materials provided with the distribution.
  18. *
  19. * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS `AS IS'
  20. * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21. * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22. * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  23. * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  24. * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  25. * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  26. * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  27. * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  28. * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  29. * POSSIBILITY OF SUCH DAMAGE.
  30. */
  31. #ifndef __BIO_H
  32. #define __BIO_H
  33. /**
  34. @file bio.h
  35. @brief Implementation of an individual bit input-output (BIO)
  36. The functions in BIO.C have for goal to realize an individual bit input - output.
  37. */
  38. /** @defgroup BIO BIO - Individual bit input-output stream */
  39. /*@{*/
  40. /**
  41. Individual bit input-output stream (BIO)
  42. */
  43. typedef struct opj_bio {
  44. /** pointer to the start of the buffer */
  45. unsigned char *start;
  46. /** pointer to the end of the buffer */
  47. unsigned char *end;
  48. /** pointer to the present position in the buffer */
  49. unsigned char *bp;
  50. /** temporary place where each byte is read or written */
  51. unsigned int buf;
  52. /** coder : number of bits free to write. decoder : number of bits read */
  53. int ct;
  54. } opj_bio_t;
  55. /** @name Exported functions */
  56. /*@{*/
  57. /* ----------------------------------------------------------------------- */
  58. /**
  59. Create a new BIO handle
  60. @return Returns a new BIO handle if successful, returns NULL otherwise
  61. */
  62. opj_bio_t* bio_create(void);
  63. /**
  64. Destroy a previously created BIO handle
  65. @param bio BIO handle to destroy
  66. */
  67. void bio_destroy(opj_bio_t *bio);
  68. /**
  69. Number of bytes written.
  70. @param bio BIO handle
  71. @return Returns the number of bytes written
  72. */
  73. int bio_numbytes(opj_bio_t *bio);
  74. /**
  75. Init encoder
  76. @param bio BIO handle
  77. @param bp Output buffer
  78. @param len Output buffer length
  79. */
  80. void bio_init_enc(opj_bio_t *bio, unsigned char *bp, int len);
  81. /**
  82. Init decoder
  83. @param bio BIO handle
  84. @param bp Input buffer
  85. @param len Input buffer length
  86. */
  87. void bio_init_dec(opj_bio_t *bio, unsigned char *bp, int len);
  88. /**
  89. Write bits
  90. @param bio BIO handle
  91. @param v Value of bits
  92. @param n Number of bits to write
  93. */
  94. void bio_write(opj_bio_t *bio, int v, int n);
  95. /**
  96. Read bits
  97. @param bio BIO handle
  98. @param n Number of bits to read
  99. @return Returns the corresponding read number
  100. */
  101. int bio_read(opj_bio_t *bio, int n);
  102. /**
  103. Flush bits
  104. @param bio BIO handle
  105. @return Returns 1 if successful, returns 0 otherwise
  106. */
  107. int bio_flush(opj_bio_t *bio);
  108. /**
  109. Passes the ending bits (coming from flushing)
  110. @param bio BIO handle
  111. @return Returns 1 if successful, returns 0 otherwise
  112. */
  113. int bio_inalign(opj_bio_t *bio);
  114. /* ----------------------------------------------------------------------- */
  115. /*@}*/
  116. /*@}*/
  117. #endif /* __BIO_H */