1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/media/libopus/celt/entenc.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,110 @@
1.4 +/* Copyright (c) 2001-2011 Timothy B. Terriberry
1.5 + Copyright (c) 2008-2009 Xiph.Org Foundation */
1.6 +/*
1.7 + Redistribution and use in source and binary forms, with or without
1.8 + modification, are permitted provided that the following conditions
1.9 + are met:
1.10 +
1.11 + - Redistributions of source code must retain the above copyright
1.12 + notice, this list of conditions and the following disclaimer.
1.13 +
1.14 + - Redistributions in binary form must reproduce the above copyright
1.15 + notice, this list of conditions and the following disclaimer in the
1.16 + documentation and/or other materials provided with the distribution.
1.17 +
1.18 + THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
1.19 + ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
1.20 + LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
1.21 + A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
1.22 + OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
1.23 + EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
1.24 + PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
1.25 + PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
1.26 + LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
1.27 + NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
1.28 + SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.29 +*/
1.30 +
1.31 +#if !defined(_entenc_H)
1.32 +# define _entenc_H (1)
1.33 +# include <stddef.h>
1.34 +# include "entcode.h"
1.35 +
1.36 +/*Initializes the encoder.
1.37 + _buf: The buffer to store output bytes in.
1.38 + _size: The size of the buffer, in chars.*/
1.39 +void ec_enc_init(ec_enc *_this,unsigned char *_buf,opus_uint32 _size);
1.40 +/*Encodes a symbol given its frequency information.
1.41 + The frequency information must be discernable by the decoder, assuming it
1.42 + has read only the previous symbols from the stream.
1.43 + It is allowable to change the frequency information, or even the entire
1.44 + source alphabet, so long as the decoder can tell from the context of the
1.45 + previously encoded information that it is supposed to do so as well.
1.46 + _fl: The cumulative frequency of all symbols that come before the one to be
1.47 + encoded.
1.48 + _fh: The cumulative frequency of all symbols up to and including the one to
1.49 + be encoded.
1.50 + Together with _fl, this defines the range [_fl,_fh) in which the
1.51 + decoded value will fall.
1.52 + _ft: The sum of the frequencies of all the symbols*/
1.53 +void ec_encode(ec_enc *_this,unsigned _fl,unsigned _fh,unsigned _ft);
1.54 +
1.55 +/*Equivalent to ec_encode() with _ft==1<<_bits.*/
1.56 +void ec_encode_bin(ec_enc *_this,unsigned _fl,unsigned _fh,unsigned _bits);
1.57 +
1.58 +/* Encode a bit that has a 1/(1<<_logp) probability of being a one */
1.59 +void ec_enc_bit_logp(ec_enc *_this,int _val,unsigned _logp);
1.60 +
1.61 +/*Encodes a symbol given an "inverse" CDF table.
1.62 + _s: The index of the symbol to encode.
1.63 + _icdf: The "inverse" CDF, such that symbol _s falls in the range
1.64 + [_s>0?ft-_icdf[_s-1]:0,ft-_icdf[_s]), where ft=1<<_ftb.
1.65 + The values must be monotonically non-increasing, and the last value
1.66 + must be 0.
1.67 + _ftb: The number of bits of precision in the cumulative distribution.*/
1.68 +void ec_enc_icdf(ec_enc *_this,int _s,const unsigned char *_icdf,unsigned _ftb);
1.69 +
1.70 +/*Encodes a raw unsigned integer in the stream.
1.71 + _fl: The integer to encode.
1.72 + _ft: The number of integers that can be encoded (one more than the max).
1.73 + This must be at least one, and no more than 2**32-1.*/
1.74 +void ec_enc_uint(ec_enc *_this,opus_uint32 _fl,opus_uint32 _ft);
1.75 +
1.76 +/*Encodes a sequence of raw bits in the stream.
1.77 + _fl: The bits to encode.
1.78 + _ftb: The number of bits to encode.
1.79 + This must be between 1 and 25, inclusive.*/
1.80 +void ec_enc_bits(ec_enc *_this,opus_uint32 _fl,unsigned _ftb);
1.81 +
1.82 +/*Overwrites a few bits at the very start of an existing stream, after they
1.83 + have already been encoded.
1.84 + This makes it possible to have a few flags up front, where it is easy for
1.85 + decoders to access them without parsing the whole stream, even if their
1.86 + values are not determined until late in the encoding process, without having
1.87 + to buffer all the intermediate symbols in the encoder.
1.88 + In order for this to work, at least _nbits bits must have already been
1.89 + encoded using probabilities that are an exact power of two.
1.90 + The encoder can verify the number of encoded bits is sufficient, but cannot
1.91 + check this latter condition.
1.92 + _val: The bits to encode (in the least _nbits significant bits).
1.93 + They will be decoded in order from most-significant to least.
1.94 + _nbits: The number of bits to overwrite.
1.95 + This must be no more than 8.*/
1.96 +void ec_enc_patch_initial_bits(ec_enc *_this,unsigned _val,unsigned _nbits);
1.97 +
1.98 +/*Compacts the data to fit in the target size.
1.99 + This moves up the raw bits at the end of the current buffer so they are at
1.100 + the end of the new buffer size.
1.101 + The caller must ensure that the amount of data that's already been written
1.102 + will fit in the new size.
1.103 + _size: The number of bytes in the new buffer.
1.104 + This must be large enough to contain the bits already written, and
1.105 + must be no larger than the existing size.*/
1.106 +void ec_enc_shrink(ec_enc *_this,opus_uint32 _size);
1.107 +
1.108 +/*Indicates that there are no more symbols to encode.
1.109 + All reamining output bytes are flushed to the output buffer.
1.110 + ec_enc_init() must be called before the encoder can be used again.*/
1.111 +void ec_enc_done(ec_enc *_this);
1.112 +
1.113 +#endif
