4ede311055
Audio notes (opus codec) A lot of different improvements and bug fixes Thanks to: https://github.com/DrKLO/Telegram/issues/293 https://github.com/DrKLO/Telegram/issues/256 FOSS configuration not ready yet I will move main dev branch to github in next couple commits
101 lines
4.7 KiB
C
101 lines
4.7 KiB
C
/* Copyright (c) 2001-2011 Timothy B. Terriberry
|
|
Copyright (c) 2008-2009 Xiph.Org Foundation */
|
|
/*
|
|
Redistribution and use in source and binary forms, with or without
|
|
modification, are permitted provided that the following conditions
|
|
are met:
|
|
|
|
- Redistributions of source code must retain the above copyright
|
|
notice, this list of conditions and the following disclaimer.
|
|
|
|
- Redistributions in binary form must reproduce the above copyright
|
|
notice, this list of conditions and the following disclaimer in the
|
|
documentation and/or other materials provided with the distribution.
|
|
|
|
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
|
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
|
|
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
|
|
OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
|
|
EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
|
|
PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
|
|
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
|
|
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
|
|
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
|
|
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
|
|
#if !defined(_entdec_H)
|
|
# define _entdec_H (1)
|
|
# include <limits.h>
|
|
# include "entcode.h"
|
|
|
|
/*Initializes the decoder.
|
|
_buf: The input buffer to use.
|
|
Return: 0 on success, or a negative value on error.*/
|
|
void ec_dec_init(ec_dec *_this,unsigned char *_buf,opus_uint32 _storage);
|
|
|
|
/*Calculates the cumulative frequency for the next symbol.
|
|
This can then be fed into the probability model to determine what that
|
|
symbol is, and the additional frequency information required to advance to
|
|
the next symbol.
|
|
This function cannot be called more than once without a corresponding call to
|
|
ec_dec_update(), or decoding will not proceed correctly.
|
|
_ft: The total frequency of the symbols in the alphabet the next symbol was
|
|
encoded with.
|
|
Return: A cumulative frequency representing the encoded symbol.
|
|
If the cumulative frequency of all the symbols before the one that
|
|
was encoded was fl, and the cumulative frequency of all the symbols
|
|
up to and including the one encoded is fh, then the returned value
|
|
will fall in the range [fl,fh).*/
|
|
unsigned ec_decode(ec_dec *_this,unsigned _ft);
|
|
|
|
/*Equivalent to ec_decode() with _ft==1<<_bits.*/
|
|
unsigned ec_decode_bin(ec_dec *_this,unsigned _bits);
|
|
|
|
/*Advance the decoder past the next symbol using the frequency information the
|
|
symbol was encoded with.
|
|
Exactly one call to ec_decode() must have been made so that all necessary
|
|
intermediate calculations are performed.
|
|
_fl: The cumulative frequency of all symbols that come before the symbol
|
|
decoded.
|
|
_fh: The cumulative frequency of all symbols up to and including the symbol
|
|
decoded.
|
|
Together with _fl, this defines the range [_fl,_fh) in which the value
|
|
returned above must fall.
|
|
_ft: The total frequency of the symbols in the alphabet the symbol decoded
|
|
was encoded in.
|
|
This must be the same as passed to the preceding call to ec_decode().*/
|
|
void ec_dec_update(ec_dec *_this,unsigned _fl,unsigned _fh,unsigned _ft);
|
|
|
|
/* Decode a bit that has a 1/(1<<_logp) probability of being a one */
|
|
int ec_dec_bit_logp(ec_dec *_this,unsigned _logp);
|
|
|
|
/*Decodes a symbol given an "inverse" CDF table.
|
|
No call to ec_dec_update() is necessary after this call.
|
|
_icdf: The "inverse" CDF, such that symbol s falls in the range
|
|
[s>0?ft-_icdf[s-1]:0,ft-_icdf[s]), where ft=1<<_ftb.
|
|
The values must be monotonically non-increasing, and the last value
|
|
must be 0.
|
|
_ftb: The number of bits of precision in the cumulative distribution.
|
|
Return: The decoded symbol s.*/
|
|
int ec_dec_icdf(ec_dec *_this,const unsigned char *_icdf,unsigned _ftb);
|
|
|
|
/*Extracts a raw unsigned integer with a non-power-of-2 range from the stream.
|
|
The bits must have been encoded with ec_enc_uint().
|
|
No call to ec_dec_update() is necessary after this call.
|
|
_ft: The number of integers that can be decoded (one more than the max).
|
|
This must be at least one, and no more than 2**32-1.
|
|
Return: The decoded bits.*/
|
|
opus_uint32 ec_dec_uint(ec_dec *_this,opus_uint32 _ft);
|
|
|
|
/*Extracts a sequence of raw bits from the stream.
|
|
The bits must have been encoded with ec_enc_bits().
|
|
No call to ec_dec_update() is necessary after this call.
|
|
_ftb: The number of bits to extract.
|
|
This must be between 0 and 25, inclusive.
|
|
Return: The decoded bits.*/
|
|
opus_uint32 ec_dec_bits(ec_dec *_this,unsigned _ftb);
|
|
|
|
#endif
|