snd_wavelet.c

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/*
===========================================================================
Copyright (C) 1999-2005 Id Software, Inc.

This file is part of Quake III Arena source code.

Quake III Arena source code is free software; you can redistribute it
and/or modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of the License,
or (at your option) any later version.

Quake III Arena source code is distributed in the hope that it will be
useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with Foobar; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
===========================================================================
*/

#include "snd_local.h"

long myftol( float f );

#define C0 0.4829629131445341
#define C1 0.8365163037378079
#define C2 0.2241438680420134
#define C3 -0.1294095225512604

void daub4(float b[], unsigned long n, int isign)
{
    float wksp[4097];
    float   *a=b-1;                     // numerical recipies so a[1] = b[0]

    unsigned long nh,nh1,i,j;

    if (n < 4) return;

    nh1=(nh=n >> 1)+1;
    if (isign >= 0) {
        for (i=1,j=1;j<=n-3;j+=2,i++) {
            wksp[i]    = C0*a[j]+C1*a[j+1]+C2*a[j+2]+C3*a[j+3];
            wksp[i+nh] = C3*a[j]-C2*a[j+1]+C1*a[j+2]-C0*a[j+3];
        }
        wksp[i   ] = C0*a[n-1]+C1*a[n]+C2*a[1]+C3*a[2];
        wksp[i+nh] = C3*a[n-1]-C2*a[n]+C1*a[1]-C0*a[2];
    } else {
        wksp[1] = C2*a[nh]+C1*a[n]+C0*a[1]+C3*a[nh1];
        wksp[2] = C3*a[nh]-C0*a[n]+C1*a[1]-C2*a[nh1];
        for (i=1,j=3;i<nh;i++) {
            wksp[j++] = C2*a[i]+C1*a[i+nh]+C0*a[i+1]+C3*a[i+nh1];
            wksp[j++] = C3*a[i]-C0*a[i+nh]+C1*a[i+1]-C2*a[i+nh1];
        }
    }
    for (i=1;i<=n;i++) {
        a[i]=wksp[i];
    }
}

void wt1(float a[], unsigned long n, int isign)
{
    unsigned long nn;
    int inverseStartLength = n/4;
    if (n < inverseStartLength) return;
    if (isign >= 0) {
        for (nn=n;nn>=inverseStartLength;nn>>=1) daub4(a,nn,isign);
    } else {
        for (nn=inverseStartLength;nn<=n;nn<<=1) daub4(a,nn,isign);
    }
}

/* The number of bits required by each value */
static unsigned char numBits[] = {
   0,1,2,2,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
   6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
   7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
   7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
   8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
   8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
   8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
   8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
};

byte MuLawEncode(short s) {
    unsigned long adjusted;
    byte sign, exponent, mantissa;

    sign = (s<0)?0:0x80;

    if (s<0) s=-s;
    adjusted = (long)s << (16-sizeof(short)*8);
    adjusted += 128L + 4L;
    if (adjusted > 32767) adjusted = 32767;
    exponent = numBits[(adjusted>>7)&0xff] - 1;
    mantissa = (adjusted>>(exponent+3))&0xf;
    return ~(sign | (exponent<<4) | mantissa);
}

short MuLawDecode(byte uLaw) {
    signed long adjusted;
    byte exponent, mantissa;

    uLaw = ~uLaw;
    exponent = (uLaw>>4) & 0x7;
    mantissa = (uLaw&0xf) + 16;
    adjusted = (mantissa << (exponent +3)) - 128 - 4;

    return (uLaw & 0x80)? adjusted : -adjusted;
}

short mulawToShort[256];
static qboolean madeTable = qfalse;

static  int NXStreamCount;

void NXPutc(NXStream *stream, char out) {
    stream[NXStreamCount++] = out;
}


void encodeWavelet( sfx_t *sfx, short *packets) {
    float   wksp[4097], temp;
    int     i, samples, size;
    sndBuffer       *newchunk, *chunk;
    byte            *out;

    if (!madeTable) {
        for (i=0;i<256;i++) {
            mulawToShort[i] = (float)MuLawDecode((byte)i);
        }
        madeTable = qtrue;
    }
    chunk = NULL;

    samples = sfx->soundLength;
    while(samples>0) {
        size = samples;
        if (size>(SND_CHUNK_SIZE*2)) {
            size = (SND_CHUNK_SIZE*2);
        }

        if (size<4) {
            size = 4;
        }

        newchunk = SND_malloc();
        if (sfx->soundData == NULL) {
            sfx->soundData = newchunk;
        } else {
            chunk->next = newchunk;
        }
        chunk = newchunk;
        for(i=0; i<size; i++) {
            wksp[i] = *packets;
            packets++;
        }
        wt1(wksp, size, 1);
        out = (byte *)chunk->sndChunk;

        for(i=0;i<size;i++) {
            temp = wksp[i];
            if (temp > 32767) temp = 32767; else if (temp<-32768) temp = -32768;
            out[i] = MuLawEncode((short)temp);
        }

        chunk->size = size;
        samples -= size;
    }
}

void decodeWavelet(sndBuffer *chunk, short *to) {
    float           wksp[4097];
    int             i;
    byte            *out;

    int size = chunk->size;
    
    out = (byte *)chunk->sndChunk;
    for(i=0;i<size;i++) {
        wksp[i] = mulawToShort[out[i]];
    }

    wt1(wksp, size, -1);
    
    if (!to) return;

    for(i=0; i<size; i++) {
        to[i] = wksp[i];
    }
}


void encodeMuLaw( sfx_t *sfx, short *packets) {
    int     i, samples, size, grade, poop;
    sndBuffer       *newchunk, *chunk;
    byte            *out;

    if (!madeTable) {
        for (i=0;i<256;i++) {
            mulawToShort[i] = (float)MuLawDecode((byte)i);
        }
        madeTable = qtrue;
    }

    chunk = NULL;
    samples = sfx->soundLength;
    grade = 0;

    while(samples>0) {
        size = samples;
        if (size>(SND_CHUNK_SIZE*2)) {
            size = (SND_CHUNK_SIZE*2);
        }

        newchunk = SND_malloc();
        if (sfx->soundData == NULL) {
            sfx->soundData = newchunk;
        } else {
            chunk->next = newchunk;
        }
        chunk = newchunk;
        out = (byte *)chunk->sndChunk;
        for(i=0; i<size; i++) {
            poop = packets[0]+grade;
            if (poop>32767) {
                poop = 32767;
            } else if (poop<-32768) {
                poop = -32768;
            }
            out[i] = MuLawEncode((short)poop);
            grade = poop - mulawToShort[out[i]];
            packets++;
        }
        chunk->size = size;
        samples -= size;
    }
}

void decodeMuLaw(sndBuffer *chunk, short *to) {
    int             i;
    byte            *out;

    int size = chunk->size;
    
    out = (byte *)chunk->sndChunk;
    for(i=0;i<size;i++) {
        to[i] = mulawToShort[out[i]];
    }
}

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