373 lines
9.9 KiB
C
373 lines
9.9 KiB
C
|
/* Copyright (C) 2002 Jean-Marc Valin
|
||
|
File: speex_bits.c
|
||
|
|
||
|
Handles bit packing/unpacking
|
||
|
|
||
|
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 HAVE_CONFIG_H
|
||
|
#include "config.h"
|
||
|
#endif
|
||
|
|
||
|
#include <speex/speex_bits.h>
|
||
|
#include "arch.h"
|
||
|
#include "os_support.h"
|
||
|
|
||
|
/* Maximum size of the bit-stream (for fixed-size allocation) */
|
||
|
#ifndef MAX_CHARS_PER_FRAME
|
||
|
#define MAX_CHARS_PER_FRAME (2000/BYTES_PER_CHAR)
|
||
|
#endif
|
||
|
|
||
|
EXPORT void speex_bits_init(SpeexBits *bits)
|
||
|
{
|
||
|
bits->chars = (char*)speex_alloc(MAX_CHARS_PER_FRAME);
|
||
|
if (!bits->chars)
|
||
|
return;
|
||
|
|
||
|
bits->buf_size = MAX_CHARS_PER_FRAME;
|
||
|
|
||
|
bits->owner=1;
|
||
|
|
||
|
speex_bits_reset(bits);
|
||
|
}
|
||
|
|
||
|
EXPORT void speex_bits_init_buffer(SpeexBits *bits, void *buff, int buf_size)
|
||
|
{
|
||
|
bits->chars = (char*)buff;
|
||
|
bits->buf_size = buf_size;
|
||
|
|
||
|
bits->owner=0;
|
||
|
|
||
|
speex_bits_reset(bits);
|
||
|
}
|
||
|
|
||
|
EXPORT void speex_bits_set_bit_buffer(SpeexBits *bits, void *buff, int buf_size)
|
||
|
{
|
||
|
bits->chars = (char*)buff;
|
||
|
bits->buf_size = buf_size;
|
||
|
|
||
|
bits->owner=0;
|
||
|
|
||
|
bits->nbBits=buf_size<<LOG2_BITS_PER_CHAR;
|
||
|
bits->charPtr=0;
|
||
|
bits->bitPtr=0;
|
||
|
bits->overflow=0;
|
||
|
|
||
|
}
|
||
|
|
||
|
EXPORT void speex_bits_destroy(SpeexBits *bits)
|
||
|
{
|
||
|
if (bits->owner)
|
||
|
speex_free(bits->chars);
|
||
|
/* Will do something once the allocation is dynamic */
|
||
|
}
|
||
|
|
||
|
EXPORT void speex_bits_reset(SpeexBits *bits)
|
||
|
{
|
||
|
/* We only need to clear the first byte now */
|
||
|
bits->chars[0]=0;
|
||
|
bits->nbBits=0;
|
||
|
bits->charPtr=0;
|
||
|
bits->bitPtr=0;
|
||
|
bits->overflow=0;
|
||
|
}
|
||
|
|
||
|
EXPORT void speex_bits_rewind(SpeexBits *bits)
|
||
|
{
|
||
|
bits->charPtr=0;
|
||
|
bits->bitPtr=0;
|
||
|
bits->overflow=0;
|
||
|
}
|
||
|
|
||
|
EXPORT void speex_bits_read_from(SpeexBits *bits, char *chars, int len)
|
||
|
{
|
||
|
int i;
|
||
|
int nchars = len / BYTES_PER_CHAR;
|
||
|
if (nchars > bits->buf_size)
|
||
|
{
|
||
|
speex_notify("Packet is larger than allocated buffer");
|
||
|
if (bits->owner)
|
||
|
{
|
||
|
char *tmp = (char*)speex_realloc(bits->chars, nchars);
|
||
|
if (tmp)
|
||
|
{
|
||
|
bits->buf_size=nchars;
|
||
|
bits->chars=tmp;
|
||
|
} else {
|
||
|
nchars=bits->buf_size;
|
||
|
speex_warning("Could not resize input buffer: truncating input");
|
||
|
}
|
||
|
} else {
|
||
|
speex_warning("Do not own input buffer: truncating oversize input");
|
||
|
nchars=bits->buf_size;
|
||
|
}
|
||
|
}
|
||
|
#if (BYTES_PER_CHAR==2)
|
||
|
/* Swap bytes to proper endian order (could be done externally) */
|
||
|
#define HTOLS(A) ((((A) >> 8)&0xff)|(((A) & 0xff)<<8))
|
||
|
#else
|
||
|
#define HTOLS(A) (A)
|
||
|
#endif
|
||
|
for (i=0;i<nchars;i++)
|
||
|
bits->chars[i]=HTOLS(chars[i]);
|
||
|
|
||
|
bits->nbBits=nchars<<LOG2_BITS_PER_CHAR;
|
||
|
bits->charPtr=0;
|
||
|
bits->bitPtr=0;
|
||
|
bits->overflow=0;
|
||
|
}
|
||
|
|
||
|
static void speex_bits_flush(SpeexBits *bits)
|
||
|
{
|
||
|
int nchars = ((bits->nbBits+BITS_PER_CHAR-1)>>LOG2_BITS_PER_CHAR);
|
||
|
if (bits->charPtr>0)
|
||
|
SPEEX_MOVE(bits->chars, &bits->chars[bits->charPtr], nchars-bits->charPtr);
|
||
|
bits->nbBits -= bits->charPtr<<LOG2_BITS_PER_CHAR;
|
||
|
bits->charPtr=0;
|
||
|
}
|
||
|
|
||
|
EXPORT void speex_bits_read_whole_bytes(SpeexBits *bits, char *chars, int nbytes)
|
||
|
{
|
||
|
int i,pos;
|
||
|
int nchars = nbytes/BYTES_PER_CHAR;
|
||
|
|
||
|
if (((bits->nbBits+BITS_PER_CHAR-1)>>LOG2_BITS_PER_CHAR)+nchars > bits->buf_size)
|
||
|
{
|
||
|
/* Packet is larger than allocated buffer */
|
||
|
if (bits->owner)
|
||
|
{
|
||
|
char *tmp = (char*)speex_realloc(bits->chars, (bits->nbBits>>LOG2_BITS_PER_CHAR)+nchars+1);
|
||
|
if (tmp)
|
||
|
{
|
||
|
bits->buf_size=(bits->nbBits>>LOG2_BITS_PER_CHAR)+nchars+1;
|
||
|
bits->chars=tmp;
|
||
|
} else {
|
||
|
nchars=bits->buf_size-(bits->nbBits>>LOG2_BITS_PER_CHAR)-1;
|
||
|
speex_warning("Could not resize input buffer: truncating oversize input");
|
||
|
}
|
||
|
} else {
|
||
|
speex_warning("Do not own input buffer: truncating oversize input");
|
||
|
nchars=bits->buf_size;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
speex_bits_flush(bits);
|
||
|
pos=bits->nbBits>>LOG2_BITS_PER_CHAR;
|
||
|
for (i=0;i<nchars;i++)
|
||
|
bits->chars[pos+i]=HTOLS(chars[i]);
|
||
|
bits->nbBits+=nchars<<LOG2_BITS_PER_CHAR;
|
||
|
}
|
||
|
|
||
|
EXPORT int speex_bits_write(SpeexBits *bits, char *chars, int max_nbytes)
|
||
|
{
|
||
|
int i;
|
||
|
int max_nchars = max_nbytes/BYTES_PER_CHAR;
|
||
|
int charPtr, bitPtr, nbBits;
|
||
|
|
||
|
/* Insert terminator, but save the data so we can put it back after */
|
||
|
bitPtr=bits->bitPtr;
|
||
|
charPtr=bits->charPtr;
|
||
|
nbBits=bits->nbBits;
|
||
|
speex_bits_insert_terminator(bits);
|
||
|
bits->bitPtr=bitPtr;
|
||
|
bits->charPtr=charPtr;
|
||
|
bits->nbBits=nbBits;
|
||
|
|
||
|
if (max_nchars > ((bits->nbBits+BITS_PER_CHAR-1)>>LOG2_BITS_PER_CHAR))
|
||
|
max_nchars = ((bits->nbBits+BITS_PER_CHAR-1)>>LOG2_BITS_PER_CHAR);
|
||
|
|
||
|
for (i=0;i<max_nchars;i++)
|
||
|
chars[i]=HTOLS(bits->chars[i]);
|
||
|
return max_nchars*BYTES_PER_CHAR;
|
||
|
}
|
||
|
|
||
|
EXPORT int speex_bits_write_whole_bytes(SpeexBits *bits, char *chars, int max_nbytes)
|
||
|
{
|
||
|
int max_nchars = max_nbytes/BYTES_PER_CHAR;
|
||
|
int i;
|
||
|
if (max_nchars > ((bits->nbBits)>>LOG2_BITS_PER_CHAR))
|
||
|
max_nchars = ((bits->nbBits)>>LOG2_BITS_PER_CHAR);
|
||
|
for (i=0;i<max_nchars;i++)
|
||
|
chars[i]=HTOLS(bits->chars[i]);
|
||
|
|
||
|
if (bits->bitPtr>0)
|
||
|
bits->chars[0]=bits->chars[max_nchars];
|
||
|
else
|
||
|
bits->chars[0]=0;
|
||
|
bits->charPtr=0;
|
||
|
bits->nbBits &= (BITS_PER_CHAR-1);
|
||
|
return max_nchars*BYTES_PER_CHAR;
|
||
|
}
|
||
|
|
||
|
EXPORT void speex_bits_pack(SpeexBits *bits, int data, int nbBits)
|
||
|
{
|
||
|
unsigned int d=data;
|
||
|
|
||
|
if (bits->charPtr+((nbBits+bits->bitPtr)>>LOG2_BITS_PER_CHAR) >= bits->buf_size)
|
||
|
{
|
||
|
speex_notify("Buffer too small to pack bits");
|
||
|
if (bits->owner)
|
||
|
{
|
||
|
int new_nchars = ((bits->buf_size+5)*3)>>1;
|
||
|
char *tmp = (char*)speex_realloc(bits->chars, new_nchars);
|
||
|
if (tmp)
|
||
|
{
|
||
|
bits->buf_size=new_nchars;
|
||
|
bits->chars=tmp;
|
||
|
} else {
|
||
|
speex_warning("Could not resize input buffer: not packing");
|
||
|
return;
|
||
|
}
|
||
|
} else {
|
||
|
speex_warning("Do not own input buffer: not packing");
|
||
|
return;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
while(nbBits)
|
||
|
{
|
||
|
int bit;
|
||
|
bit = (d>>(nbBits-1))&1;
|
||
|
bits->chars[bits->charPtr] |= bit<<(BITS_PER_CHAR-1-bits->bitPtr);
|
||
|
bits->bitPtr++;
|
||
|
|
||
|
if (bits->bitPtr==BITS_PER_CHAR)
|
||
|
{
|
||
|
bits->bitPtr=0;
|
||
|
bits->charPtr++;
|
||
|
bits->chars[bits->charPtr] = 0;
|
||
|
}
|
||
|
bits->nbBits++;
|
||
|
nbBits--;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
EXPORT int speex_bits_unpack_signed(SpeexBits *bits, int nbBits)
|
||
|
{
|
||
|
unsigned int d=speex_bits_unpack_unsigned(bits,nbBits);
|
||
|
/* If number is negative */
|
||
|
if (d>>(nbBits-1))
|
||
|
{
|
||
|
d |= (-1)<<nbBits;
|
||
|
}
|
||
|
return d;
|
||
|
}
|
||
|
|
||
|
EXPORT unsigned int speex_bits_unpack_unsigned(SpeexBits *bits, int nbBits)
|
||
|
{
|
||
|
unsigned int d=0;
|
||
|
if ((bits->charPtr<<LOG2_BITS_PER_CHAR)+bits->bitPtr+nbBits>bits->nbBits)
|
||
|
bits->overflow=1;
|
||
|
if (bits->overflow)
|
||
|
return 0;
|
||
|
while(nbBits)
|
||
|
{
|
||
|
d<<=1;
|
||
|
d |= (bits->chars[bits->charPtr]>>(BITS_PER_CHAR-1 - bits->bitPtr))&1;
|
||
|
bits->bitPtr++;
|
||
|
if (bits->bitPtr==BITS_PER_CHAR)
|
||
|
{
|
||
|
bits->bitPtr=0;
|
||
|
bits->charPtr++;
|
||
|
}
|
||
|
nbBits--;
|
||
|
}
|
||
|
return d;
|
||
|
}
|
||
|
|
||
|
EXPORT unsigned int speex_bits_peek_unsigned(SpeexBits *bits, int nbBits)
|
||
|
{
|
||
|
unsigned int d=0;
|
||
|
int bitPtr, charPtr;
|
||
|
char *chars;
|
||
|
|
||
|
if ((bits->charPtr<<LOG2_BITS_PER_CHAR)+bits->bitPtr+nbBits>bits->nbBits)
|
||
|
bits->overflow=1;
|
||
|
if (bits->overflow)
|
||
|
return 0;
|
||
|
|
||
|
bitPtr=bits->bitPtr;
|
||
|
charPtr=bits->charPtr;
|
||
|
chars = bits->chars;
|
||
|
while(nbBits)
|
||
|
{
|
||
|
d<<=1;
|
||
|
d |= (chars[charPtr]>>(BITS_PER_CHAR-1 - bitPtr))&1;
|
||
|
bitPtr++;
|
||
|
if (bitPtr==BITS_PER_CHAR)
|
||
|
{
|
||
|
bitPtr=0;
|
||
|
charPtr++;
|
||
|
}
|
||
|
nbBits--;
|
||
|
}
|
||
|
return d;
|
||
|
}
|
||
|
|
||
|
EXPORT int speex_bits_peek(SpeexBits *bits)
|
||
|
{
|
||
|
if ((bits->charPtr<<LOG2_BITS_PER_CHAR)+bits->bitPtr+1>bits->nbBits)
|
||
|
bits->overflow=1;
|
||
|
if (bits->overflow)
|
||
|
return 0;
|
||
|
return (bits->chars[bits->charPtr]>>(BITS_PER_CHAR-1 - bits->bitPtr))&1;
|
||
|
}
|
||
|
|
||
|
EXPORT void speex_bits_advance(SpeexBits *bits, int n)
|
||
|
{
|
||
|
if (((bits->charPtr<<LOG2_BITS_PER_CHAR)+bits->bitPtr+n>bits->nbBits) || bits->overflow){
|
||
|
bits->overflow=1;
|
||
|
return;
|
||
|
}
|
||
|
bits->charPtr += (bits->bitPtr+n) >> LOG2_BITS_PER_CHAR; /* divide by BITS_PER_CHAR */
|
||
|
bits->bitPtr = (bits->bitPtr+n) & (BITS_PER_CHAR-1); /* modulo by BITS_PER_CHAR */
|
||
|
}
|
||
|
|
||
|
EXPORT int speex_bits_remaining(SpeexBits *bits)
|
||
|
{
|
||
|
if (bits->overflow)
|
||
|
return -1;
|
||
|
else
|
||
|
return bits->nbBits-((bits->charPtr<<LOG2_BITS_PER_CHAR)+bits->bitPtr);
|
||
|
}
|
||
|
|
||
|
EXPORT int speex_bits_nbytes(SpeexBits *bits)
|
||
|
{
|
||
|
return ((bits->nbBits+BITS_PER_CHAR-1)>>LOG2_BITS_PER_CHAR);
|
||
|
}
|
||
|
|
||
|
EXPORT void speex_bits_insert_terminator(SpeexBits *bits)
|
||
|
{
|
||
|
if (bits->bitPtr)
|
||
|
speex_bits_pack(bits, 0, 1);
|
||
|
while (bits->bitPtr)
|
||
|
speex_bits_pack(bits, 1, 1);
|
||
|
}
|