view libgsmefr/oper_32b.h @ 485:751f06541fbb

doc/Codec-utils: clarify lack of DHF in gsmfr-decode-rb
author Mychaela Falconia <falcon@freecalypso.org>
date Mon, 20 May 2024 01:47:22 +0000
parents 3da7ab45910d
children
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/* Double precision operations */

/*****************************************************************************
 *                                                                           *
 *  Function L_Extract()                                                     *
 *                                                                           *
 *  Extract from a 32 bit integer two 16 bit DPF.                            *
 *                                                                           *
 *  Arguments:                                                               *
 *                                                                           *
 *   L_32      : 32 bit integer.                                             *
 *               0x8000 0000 <= L_32 <= 0x7fff ffff.                         *
 *   hi        : b16 to b31 of L_32                                          *
 *   lo        : (L_32 - hi<<16)>>1                                          *
 *****************************************************************************
*/

static inline void L_Extract (Word32 L_32, Word16 *hi, Word16 *lo)
{
    *hi = L_32 >> 16;
    *lo = (L_32 & 0xFFFF) >> 1;
}

/*****************************************************************************
 *                                                                           *
 *  Function L_Comp()                                                        *
 *                                                                           *
 *  Compose from two 16 bit DPF a 32 bit integer.                            *
 *                                                                           *
 *     L_32 = hi<<16 + lo<<1                                                 *
 *                                                                           *
 *  Arguments:                                                               *
 *                                                                           *
 *   hi        msb                                                           *
 *   lo        lsf (with sign)                                               *
 *                                                                           *
 *   Return Value :                                                          *
 *                                                                           *
 *             32 bit long signed integer (Word32) whose value falls in the  *
 *             range : 0x8000 0000 <= L_32 <= 0x7fff fff0.                   *
 *                                                                           *
 *****************************************************************************
*/

static inline Word32 L_Comp (Word16 hi, Word16 lo)
{
    return ((Word32) hi << 16) + ((Word32) lo << 1);
}

Word32 Mpy_32 (Word16 hi1, Word16 lo1, Word16 hi2, Word16 lo2);
Word32 Mpy_32_16 (Word16 hi, Word16 lo, Word16 n);
Word32 Div_32 (Word32 L_num, Word16 denom_hi, Word16 denom_lo);