Index: speex/libspeex/bits.c |
=================================================================== |
--- speex/libspeex/bits.c (revision 0) |
+++ speex/libspeex/bits.c (revision 0) |
@@ -0,0 +1,372 @@ |
+/* 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); |
+} |
Property changes on: speex/libspeex/bits.c |
___________________________________________________________________ |
Name: svn:executable |
+ * |