chore(fmod): add files from Chensne/DragonNest
This commit is contained in:
commit
50fb3c6b1c
544 changed files with 315778 additions and 0 deletions
196
lib/libcelt/rangeenc.c
Executable file
196
lib/libcelt/rangeenc.c
Executable file
|
|
@ -0,0 +1,196 @@
|
|||
/* (C) 2001-2008 Timothy B. Terriberry
|
||||
(C) 2008 Jean-Marc Valin */
|
||||
/*
|
||||
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.
|
||||
|
||||
- Neither the name of the Xiph.org Foundation nor the names of its
|
||||
contributors may be used to endorse or promote products derived from
|
||||
this software without specific prior written permission.
|
||||
|
||||
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 FOUNDATION 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.
|
||||
*/
|
||||
|
||||
#ifdef FMOD_CELT_ENCODER
|
||||
|
||||
#ifdef HAVE_CONFIG_H
|
||||
#include "config.h"
|
||||
#endif
|
||||
|
||||
#include "arch.h"
|
||||
#include "entenc.h"
|
||||
#include "mfrngcod.h"
|
||||
|
||||
|
||||
|
||||
/*A range encoder.
|
||||
See rangedec.c and the references for implementation details
|
||||
\cite{Mar79,MNW98}.
|
||||
|
||||
@INPROCEEDINGS{Mar79,
|
||||
author="Martin, G.N.N.",
|
||||
title="Range encoding: an algorithm for removing redundancy from a digitised
|
||||
message",
|
||||
booktitle="Video \& Data Recording Conference",
|
||||
year=1979,
|
||||
address="Southampton",
|
||||
month=Jul
|
||||
}
|
||||
@ARTICLE{MNW98,
|
||||
author="Alistair Moffat and Radford Neal and Ian H. Witten",
|
||||
title="Arithmetic Coding Revisited",
|
||||
journal="{ACM} Transactions on Information Systems",
|
||||
year=1998,
|
||||
volume=16,
|
||||
number=3,
|
||||
pages="256--294",
|
||||
month=Jul,
|
||||
URL="http://www.stanford.edu/class/ee398/handouts/papers/Moffat98ArithmCoding.pdf"
|
||||
}*/
|
||||
|
||||
|
||||
|
||||
/*Outputs a symbol, with a carry bit.
|
||||
If there is a potential to propagate a carry over several symbols, they are
|
||||
buffered until it can be determined whether or not an actual carry will
|
||||
occur.
|
||||
If the counter for the buffered symbols overflows, then the stream becomes
|
||||
undecodable.
|
||||
This gives a theoretical limit of a few billion symbols in a single packet on
|
||||
32-bit systems.
|
||||
The alternative is to truncate the range in order to force a carry, but
|
||||
requires similar carry tracking in the decoder, needlessly slowing it down.*/
|
||||
static void ec_enc_carry_out(ec_enc *_this,int _c){
|
||||
if(_c!=EC_SYM_MAX){
|
||||
/*No further carry propagation possible, flush buffer.*/
|
||||
int carry;
|
||||
carry=_c>>EC_SYM_BITS;
|
||||
/*Don't output a byte on the first write.
|
||||
This compare should be taken care of by branch-prediction thereafter.*/
|
||||
if(_this->rem>=0)ec_byte_write1(_this->buf,_this->rem+carry);
|
||||
if(_this->ext>0){
|
||||
unsigned sym;
|
||||
sym=EC_SYM_MAX+carry&EC_SYM_MAX;
|
||||
do ec_byte_write1(_this->buf,sym);
|
||||
while(--(_this->ext)>0);
|
||||
}
|
||||
_this->rem=_c&EC_SYM_MAX;
|
||||
}
|
||||
else _this->ext++;
|
||||
}
|
||||
|
||||
static FMOD_INLINE void ec_enc_normalize(ec_enc *_this){
|
||||
/*If the range is too small, output some bits and rescale it.*/
|
||||
while(_this->rng<=EC_CODE_BOT){
|
||||
ec_enc_carry_out(_this,(int)(_this->low>>EC_CODE_SHIFT));
|
||||
/*Move the next-to-high-order symbol into the high-order position.*/
|
||||
_this->low=_this->low<<EC_SYM_BITS&EC_CODE_TOP-1;
|
||||
_this->rng<<=EC_SYM_BITS;
|
||||
}
|
||||
}
|
||||
|
||||
void ec_enc_init(ec_enc *_this,ec_byte_buffer *_buf){
|
||||
_this->buf=_buf;
|
||||
_this->rem=-1;
|
||||
_this->ext=0;
|
||||
_this->low=0;
|
||||
_this->rng=EC_CODE_TOP;
|
||||
}
|
||||
|
||||
void ec_encode(ec_enc *_this,unsigned _fl,unsigned _fh,unsigned _ft){
|
||||
ec_uint32 r;
|
||||
r=_this->rng/_ft;
|
||||
if(_fl>0){
|
||||
_this->low+=_this->rng-IMUL32(r,(_ft-_fl));
|
||||
_this->rng=IMUL32(r,(_fh-_fl));
|
||||
}
|
||||
else _this->rng-=IMUL32(r,(_ft-_fh));
|
||||
ec_enc_normalize(_this);
|
||||
}
|
||||
|
||||
void ec_encode_bin(ec_enc *_this,unsigned _fl,unsigned _fh,unsigned bits){
|
||||
ec_uint32 r, ft;
|
||||
r=_this->rng>>bits;
|
||||
ft = (ec_uint32)1<<bits;
|
||||
if(_fl>0){
|
||||
_this->low+=_this->rng-IMUL32(r,(ft-_fl));
|
||||
_this->rng=IMUL32(r,(_fh-_fl));
|
||||
}
|
||||
else _this->rng-=IMUL32(r,(ft-_fh));
|
||||
ec_enc_normalize(_this);
|
||||
}
|
||||
|
||||
long ec_enc_tell(ec_enc *_this,int _b){
|
||||
ec_uint32 r;
|
||||
int l;
|
||||
long nbits;
|
||||
nbits=(ec_byte_bytes(_this->buf)+(_this->rem>=0)+_this->ext)*EC_SYM_BITS;
|
||||
/*To handle the non-integral number of bits still left in the encoder state,
|
||||
we compute the number of bits of low that must be encoded to ensure that
|
||||
the value is inside the range for any possible subsequent bits.
|
||||
Note that this is subtly different than the actual value we would end the
|
||||
stream with, which tries to make as many of the trailing bits zeros as
|
||||
possible.*/
|
||||
nbits+=EC_CODE_BITS;
|
||||
nbits<<=_b;
|
||||
l=EC_ILOG(_this->rng);
|
||||
r=_this->rng>>l-16;
|
||||
while(_b-->0){
|
||||
int b;
|
||||
r=r*r>>15;
|
||||
b=(int)(r>>16);
|
||||
l=l<<1|b;
|
||||
r>>=b;
|
||||
}
|
||||
return nbits-l;
|
||||
}
|
||||
|
||||
void ec_enc_done(ec_enc *_this){
|
||||
/*We compute the integer in the current interval that has the largest number
|
||||
of trailing zeros, and write that to the stream.
|
||||
This is guaranteed to yield the smallest possible encoding.*/
|
||||
if(_this->low){
|
||||
ec_uint32 end;
|
||||
end=EC_CODE_TOP;
|
||||
/*Ensure that the end value is in the range.*/
|
||||
if(end-_this->low>=_this->rng){
|
||||
ec_uint32 msk;
|
||||
msk=EC_CODE_TOP-1;
|
||||
do{
|
||||
msk>>=1;
|
||||
end=_this->low+msk&~msk|msk+1;
|
||||
}
|
||||
while(end-_this->low>=_this->rng);
|
||||
}
|
||||
/*The remaining output is the next free end.*/
|
||||
while(end){
|
||||
ec_enc_carry_out(_this,end>>EC_CODE_SHIFT);
|
||||
end=end<<EC_SYM_BITS&EC_CODE_TOP-1;
|
||||
}
|
||||
}
|
||||
/*If we have a buffered byte flush it into the output buffer.*/
|
||||
if(_this->rem>0||_this->ext>0){
|
||||
ec_enc_carry_out(_this,0);
|
||||
_this->rem=-1;
|
||||
}
|
||||
}
|
||||
|
||||
#endif /* FMOD_CELT_ENCODER */
|
||||
Loading…
Add table
Add a link
Reference in a new issue