xref: /aosp_15_r20/external/libopus/celt/mfrngcod.h (revision a58d3d2adb790c104798cd88c8a3aff4fa8b82cc)
1*a58d3d2aSXin Li /* Copyright (c) 2001-2008 Timothy B. Terriberry
2*a58d3d2aSXin Li    Copyright (c) 2008-2009 Xiph.Org Foundation */
3*a58d3d2aSXin Li /*
4*a58d3d2aSXin Li    Redistribution and use in source and binary forms, with or without
5*a58d3d2aSXin Li    modification, are permitted provided that the following conditions
6*a58d3d2aSXin Li    are met:
7*a58d3d2aSXin Li 
8*a58d3d2aSXin Li    - Redistributions of source code must retain the above copyright
9*a58d3d2aSXin Li    notice, this list of conditions and the following disclaimer.
10*a58d3d2aSXin Li 
11*a58d3d2aSXin Li    - Redistributions in binary form must reproduce the above copyright
12*a58d3d2aSXin Li    notice, this list of conditions and the following disclaimer in the
13*a58d3d2aSXin Li    documentation and/or other materials provided with the distribution.
14*a58d3d2aSXin Li 
15*a58d3d2aSXin Li    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16*a58d3d2aSXin Li    ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17*a58d3d2aSXin Li    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
18*a58d3d2aSXin Li    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
19*a58d3d2aSXin Li    OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
20*a58d3d2aSXin Li    EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
21*a58d3d2aSXin Li    PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
22*a58d3d2aSXin Li    PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
23*a58d3d2aSXin Li    LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
24*a58d3d2aSXin Li    NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
25*a58d3d2aSXin Li    SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26*a58d3d2aSXin Li */
27*a58d3d2aSXin Li 
28*a58d3d2aSXin Li #if !defined(_mfrngcode_H)
29*a58d3d2aSXin Li # define _mfrngcode_H (1)
30*a58d3d2aSXin Li # include "entcode.h"
31*a58d3d2aSXin Li 
32*a58d3d2aSXin Li /*Constants used by the entropy encoder/decoder.*/
33*a58d3d2aSXin Li 
34*a58d3d2aSXin Li /*The number of bits to output at a time.*/
35*a58d3d2aSXin Li # define EC_SYM_BITS   (8)
36*a58d3d2aSXin Li /*The total number of bits in each of the state registers.*/
37*a58d3d2aSXin Li # define EC_CODE_BITS  (32)
38*a58d3d2aSXin Li /*The maximum symbol value.*/
39*a58d3d2aSXin Li # define EC_SYM_MAX    ((1U<<EC_SYM_BITS)-1)
40*a58d3d2aSXin Li /*Bits to shift by to move a symbol into the high-order position.*/
41*a58d3d2aSXin Li # define EC_CODE_SHIFT (EC_CODE_BITS-EC_SYM_BITS-1)
42*a58d3d2aSXin Li /*Carry bit of the high-order range symbol.*/
43*a58d3d2aSXin Li # define EC_CODE_TOP   (((opus_uint32)1U)<<(EC_CODE_BITS-1))
44*a58d3d2aSXin Li /*Low-order bit of the high-order range symbol.*/
45*a58d3d2aSXin Li # define EC_CODE_BOT   (EC_CODE_TOP>>EC_SYM_BITS)
46*a58d3d2aSXin Li /*The number of bits available for the last, partial symbol in the code field.*/
47*a58d3d2aSXin Li # define EC_CODE_EXTRA ((EC_CODE_BITS-2)%EC_SYM_BITS+1)
48*a58d3d2aSXin Li #endif
49