fix.h 2.3 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 __FIX_H
  32. #define __FIX_H
  33. #if defined(_MSC_VER) || defined(__BORLANDC__)
  34. #define int64 __int64
  35. #else
  36. #define int64 long long
  37. #endif
  38. /**
  39. @file fix.h
  40. @brief Implementation of operations of specific multiplication (FIX)
  41. The functions in FIX.H have for goal to realize specific multiplication.
  42. */
  43. /** @defgroup FIX FIX - Implementation of operations of specific multiplication */
  44. /*@{*/
  45. /**
  46. Multiply two fixed-precision rational numbers.
  47. @param a
  48. @param b
  49. @return Returns a * b
  50. */
  51. static INLINE int fix_mul(int a, int b) {
  52. int64 temp = (int64) a * (int64) b ;
  53. temp += temp & 4096;
  54. return (int) (temp >> 13) ;
  55. }
  56. /*@}*/
  57. #endif /* __FIX_H */