The Tor Browser / file comparison
comparison: media/libopus/celt/entdec.h
media/libopus/celt/entdec.h
- changeset 0
- 6474c204b198
equal
deleted
inserted
replaced
| -1:000000000000 | 0:5bf29f3cada2 |
|---|---|
| 1 /* Copyright (c) 2001-2011 Timothy B. Terriberry | |
| 2 Copyright (c) 2008-2009 Xiph.Org Foundation */ | |
| 3 /* | |
| 4 Redistribution and use in source and binary forms, with or without | |
| 5 modification, are permitted provided that the following conditions | |
| 6 are met: | |
| 7 | |
| 8 - Redistributions of source code must retain the above copyright | |
| 9 notice, this list of conditions and the following disclaimer. | |
| 10 | |
| 11 - Redistributions in binary form must reproduce the above copyright | |
| 12 notice, this list of conditions and the following disclaimer in the | |
| 13 documentation and/or other materials provided with the distribution. | |
| 14 | |
| 15 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS | |
| 16 ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT | |
| 17 LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR | |
| 18 A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER | |
| 19 OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, | |
| 20 EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, | |
| 21 PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR | |
| 22 PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF | |
| 23 LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING | |
| 24 NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS | |
| 25 SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
| 26 */ | |
| 27 | |
| 28 #if !defined(_entdec_H) | |
| 29 # define _entdec_H (1) | |
| 30 # include <limits.h> | |
| 31 # include "entcode.h" | |
| 32 | |
| 33 /*Initializes the decoder. | |
| 34 _buf: The input buffer to use. | |
| 35 Return: 0 on success, or a negative value on error.*/ | |
| 36 void ec_dec_init(ec_dec *_this,unsigned char *_buf,opus_uint32 _storage); | |
| 37 | |
| 38 /*Calculates the cumulative frequency for the next symbol. | |
| 39 This can then be fed into the probability model to determine what that | |
| 40 symbol is, and the additional frequency information required to advance to | |
| 41 the next symbol. | |
| 42 This function cannot be called more than once without a corresponding call to | |
| 43 ec_dec_update(), or decoding will not proceed correctly. | |
| 44 _ft: The total frequency of the symbols in the alphabet the next symbol was | |
| 45 encoded with. | |
| 46 Return: A cumulative frequency representing the encoded symbol. | |
| 47 If the cumulative frequency of all the symbols before the one that | |
| 48 was encoded was fl, and the cumulative frequency of all the symbols | |
| 49 up to and including the one encoded is fh, then the returned value | |
| 50 will fall in the range [fl,fh).*/ | |
| 51 unsigned ec_decode(ec_dec *_this,unsigned _ft); | |
| 52 | |
| 53 /*Equivalent to ec_decode() with _ft==1<<_bits.*/ | |
| 54 unsigned ec_decode_bin(ec_dec *_this,unsigned _bits); | |
| 55 | |
| 56 /*Advance the decoder past the next symbol using the frequency information the | |
| 57 symbol was encoded with. | |
| 58 Exactly one call to ec_decode() must have been made so that all necessary | |
| 59 intermediate calculations are performed. | |
| 60 _fl: The cumulative frequency of all symbols that come before the symbol | |
| 61 decoded. | |
| 62 _fh: The cumulative frequency of all symbols up to and including the symbol | |
| 63 decoded. | |
| 64 Together with _fl, this defines the range [_fl,_fh) in which the value | |
| 65 returned above must fall. | |
| 66 _ft: The total frequency of the symbols in the alphabet the symbol decoded | |
| 67 was encoded in. | |
| 68 This must be the same as passed to the preceding call to ec_decode().*/ | |
| 69 void ec_dec_update(ec_dec *_this,unsigned _fl,unsigned _fh,unsigned _ft); | |
| 70 | |
| 71 /* Decode a bit that has a 1/(1<<_logp) probability of being a one */ | |
| 72 int ec_dec_bit_logp(ec_dec *_this,unsigned _logp); | |
| 73 | |
| 74 /*Decodes a symbol given an "inverse" CDF table. | |
| 75 No call to ec_dec_update() is necessary after this call. | |
| 76 _icdf: The "inverse" CDF, such that symbol s falls in the range | |
| 77 [s>0?ft-_icdf[s-1]:0,ft-_icdf[s]), where ft=1<<_ftb. | |
| 78 The values must be monotonically non-increasing, and the last value | |
| 79 must be 0. | |
| 80 _ftb: The number of bits of precision in the cumulative distribution. | |
| 81 Return: The decoded symbol s.*/ | |
| 82 int ec_dec_icdf(ec_dec *_this,const unsigned char *_icdf,unsigned _ftb); | |
| 83 | |
| 84 /*Extracts a raw unsigned integer with a non-power-of-2 range from the stream. | |
| 85 The bits must have been encoded with ec_enc_uint(). | |
| 86 No call to ec_dec_update() is necessary after this call. | |
| 87 _ft: The number of integers that can be decoded (one more than the max). | |
| 88 This must be at least one, and no more than 2**32-1. | |
| 89 Return: The decoded bits.*/ | |
| 90 opus_uint32 ec_dec_uint(ec_dec *_this,opus_uint32 _ft); | |
| 91 | |
| 92 /*Extracts a sequence of raw bits from the stream. | |
| 93 The bits must have been encoded with ec_enc_bits(). | |
| 94 No call to ec_dec_update() is necessary after this call. | |
| 95 _ftb: The number of bits to extract. | |
| 96 This must be between 0 and 25, inclusive. | |
| 97 Return: The decoded bits.*/ | |
| 98 opus_uint32 ec_dec_bits(ec_dec *_this,unsigned _ftb); | |
| 99 | |
| 100 #endif |
