ref: 949a29bf0c7305bd79021815a06123b343972743
parent: 50cf82f7abebea4f46c296e674820eb04d0551fd
author: Jean-Marc Valin <[email protected]>
date: Sat Jul 25 16:16:01 EDT 2009
Raw bits encoding/decoding functions renamed to *_raw() and re-introducing original ec_encode_bin()/ec_decode_bin() to optimize performance when ft is a power of two.
--- a/libcelt/entdec.c
+++ b/libcelt/entdec.c
@@ -128,13 +128,13 @@
unsigned ft;
t=0;
while(_ftb>EC_UNIT_BITS){- s=ec_decode_bin(_this,EC_UNIT_BITS);
+ s=ec_decode_raw(_this,EC_UNIT_BITS);
/*ec_dec_update(_this,s,s+1,EC_UNIT_MASK+1);*/
t=t<<EC_UNIT_BITS|s;
_ftb-=EC_UNIT_BITS;
}
ft=1U<<_ftb;
- s=ec_decode_bin(_this,_ftb);
+ s=ec_decode_raw(_this,_ftb);
/*ec_dec_update(_this,s,s+1,ft);*/
t=t<<_ftb|s;
return t;
--- a/libcelt/entdec.h
+++ b/libcelt/entdec.h
@@ -78,7 +78,9 @@
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);
-unsigned ec_decode_bin(ec_dec *_this,unsigned bits);
+unsigned ec_decode_bin(ec_dec *_this,unsigned _bits);
+unsigned ec_decode_raw(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
--- a/libcelt/entenc.c
+++ b/libcelt/entenc.c
@@ -131,11 +131,11 @@
while(_ftb>EC_UNIT_BITS){_ftb-=EC_UNIT_BITS;
fl=(unsigned)(_fl>>_ftb)&EC_UNIT_MASK;
- ec_encode_bin(_this,fl,fl+1,EC_UNIT_BITS);
+ ec_encode_raw(_this,fl,fl+1,EC_UNIT_BITS);
}
ft=1<<_ftb;
fl=(unsigned)_fl&ft-1;
- ec_encode_bin(_this,fl,fl+1,_ftb);
+ ec_encode_raw(_this,fl,fl+1,_ftb);
}
void ec_enc_uint(ec_enc *_this,ec_uint32 _fl,ec_uint32 _ft){--- a/libcelt/entenc.h
+++ b/libcelt/entenc.h
@@ -78,7 +78,8 @@
decoded value will fall.
_ft: The sum of the frequencies of all the symbols*/
void ec_encode(ec_enc *_this,unsigned _fl,unsigned _fh,unsigned _ft);
-void ec_encode_bin(ec_enc *_this,unsigned _fl,unsigned _fh,unsigned bits);
+void ec_encode_bin(ec_enc *_this,unsigned _fl,unsigned _fh,unsigned _bits);
+void ec_encode_raw(ec_enc *_this,unsigned _fl,unsigned _fh,unsigned bits);
/*Encodes a sequence of raw bits in the stream.
_fl: The bits to encode.
_ftb: The number of bits to encode.
--- a/libcelt/laplace.c
+++ b/libcelt/laplace.c
@@ -84,7 +84,7 @@
fl = 0;
if (s)
fl += fs;
- ec_encode(enc, fl, fl+fs, ft);
+ ec_encode_bin(enc, fl, fl+fs, 15);
}
void ec_laplace_encode(ec_enc *enc, int *value, int decay)
@@ -102,7 +102,7 @@
fl = 0;
ft = 32768;
fh = fs;
- fm = ec_decode(dec, ft);
+ fm = ec_decode_bin(dec, 15);
while (fm >= fh && fs != 0)
{fl = fh;
--- a/libcelt/rangedec.c
+++ b/libcelt/rangedec.c
@@ -154,15 +154,14 @@
return _ft-EC_MINI(s+1,_ft);
}
-unsigned ec_decode_bin(ec_dec *_this,unsigned bits){-#if 0
+unsigned ec_decode_bin(ec_dec *_this,unsigned _bits){unsigned s;
- ec_uint32 ft;
- ft = (ec_uint32)1<<bits;
- _this->nrm=_this->rng>>bits;
+ _this->nrm=_this->rng>>_bits;
s=(unsigned)((_this->dif-1)/_this->nrm);
- return ft-EC_MINI(s+1,ft);
-#else
+ return (1<<_bits)-EC_MINI(s+1,1<<_bits);
+}
+
+unsigned ec_decode_raw(ec_dec *_this,unsigned bits){unsigned value=0;
int count=0;
_this->nb_end_bits += bits;
@@ -177,7 +176,6 @@
value |= ((_this->end_byte>>(8-_this->end_bits_left))&((1<<bits)-1))<<count;
_this->end_bits_left -= bits;
return value;
-#endif
}
void ec_dec_update(ec_dec *_this,unsigned _fl,unsigned _fh,unsigned _ft){--- a/libcelt/rangeenc.c
+++ b/libcelt/rangeenc.c
@@ -127,18 +127,18 @@
ec_enc_normalize(_this);
}
-void ec_encode_bin(ec_enc *_this,unsigned _fl,unsigned _fh,unsigned bits){-#if 0
- ec_uint32 r, ft;
- r=_this->rng>>bits;
- ft = (ec_uint32)1<<bits;
+void ec_encode_bin(ec_enc *_this,unsigned _fl,unsigned _fh,unsigned _bits){+ ec_uint32 r;
+ r=_this->rng>>_bits;
if(_fl>0){- _this->low+=_this->rng-IMUL32(r,(ft-_fl));
- _this->rng=IMUL32(r,(_fh-_fl));
+ _this->low+=_this->rng-IMUL32(r,((1<<_bits)-_fl));
+ _this->rng=IMUL32(r,(_fh-_fl));
}
- else _this->rng-=IMUL32(r,(ft-_fh));
+ else _this->rng-=IMUL32(r,((1<<_bits)-_fh));
ec_enc_normalize(_this);
-#else
+}
+
+void ec_encode_raw(ec_enc *_this,unsigned _fl,unsigned _fh,unsigned bits){_this->nb_end_bits += bits;
while (bits >= _this->end_bits_left)
{@@ -151,7 +151,6 @@
}
_this->end_byte |= (_fl<<(8-_this->end_bits_left)) & 0xff;
_this->end_bits_left -= bits;
-#endif
}
long ec_enc_tell(ec_enc *_this,int _b){