filter.cc

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/* MPEG/WAVE Sound library

   (C) 1997 by Jung woo-jae */

// Filter.cc
// Subbandsynthesis routines from maplay 1.2 for Linux
// I've modified some macros for reducing source code.

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "mpegsound.h"

void
Mpegtoraw::computebuffer(REAL * fraction, REAL buffer[2][CALCBUFFERSIZE])
{
    REAL p0, p1, p2, p3, p4, p5, p6, p7, p8, p9, pa, pb, pc, pd, pe, pf;
    REAL q0, q1, q2, q3, q4, q5, q6, q7, q8, q9, qa, qb, qc, qd, qe, qf;
    REAL *out1, *out2;

    out1 = buffer[currentcalcbuffer] + calcbufferoffset;
    out2 = buffer[currentcalcbuffer ^ 1] + calcbufferoffset;
#define OUT1(v,t) out1[(32-(v))*16]   =(-(out1[(v)*16]=t))
#define OUT2(v)   out2[(96-(v)-32)*16]=out2[((v)-32)*16]

    // compute new values via a fast cosine transform:
    {
	register REAL *x = fraction;

	p0 = x[0] + x[31];
	p1 = x[1] + x[30];
	p2 = x[2] + x[29];
	p3 = x[3] + x[28];
	p4 = x[4] + x[27];
	p5 = x[5] + x[26];
	p6 = x[6] + x[25];
	p7 = x[7] + x[24];
	p8 = x[8] + x[23];
	p9 = x[9] + x[22];
	pa = x[10] + x[21];
	pb = x[11] + x[20];
	pc = x[12] + x[19];
	pd = x[13] + x[18];
	pe = x[14] + x[17];
	pf = x[15] + x[16];
    }


    q0 = p0 + pf;
    q1 = p1 + pe;
    q2 = p2 + pd;
    q3 = p3 + pc;
    q4 = p4 + pb;
    q5 = p5 + pa;
    q6 = p6 + p9;
    q7 = p7 + p8;
    q8 = hcos_32[0] * (p0 - pf);
    q9 = hcos_32[1] * (p1 - pe);
    qa = hcos_32[2] * (p2 - pd);
    qb = hcos_32[3] * (p3 - pc);
    qc = hcos_32[4] * (p4 - pb);
    qd = hcos_32[5] * (p5 - pa);
    qe = hcos_32[6] * (p6 - p9);
    qf = hcos_32[7] * (p7 - p8);

    p0 = q0 + q7;
    p1 = q1 + q6;
    p2 = q2 + q5;
    p3 = q3 + q4;
    p4 = hcos_16[0] * (q0 - q7);
    p5 = hcos_16[1] * (q1 - q6);
    p6 = hcos_16[2] * (q2 - q5);
    p7 = hcos_16[3] * (q3 - q4);
    p8 = q8 + qf;
    p9 = q9 + qe;
    pa = qa + qd;
    pb = qb + qc;
    pc = hcos_16[0] * (q8 - qf);
    pd = hcos_16[1] * (q9 - qe);
    pe = hcos_16[2] * (qa - qd);
    pf = hcos_16[3] * (qb - qc);

    q0 = p0 + p3;
    q1 = p1 + p2;
    q2 = hcos_8[0] * (p0 - p3);
    q3 = hcos_8[1] * (p1 - p2);
    q4 = p4 + p7;
    q5 = p5 + p6;
    q6 = hcos_8[0] * (p4 - p7);
    q7 = hcos_8[1] * (p5 - p6);
    q8 = p8 + pb;
    q9 = p9 + pa;
    qa = hcos_8[0] * (p8 - pb);
    qb = hcos_8[1] * (p9 - pa);
    qc = pc + pf;
    qd = pd + pe;
    qe = hcos_8[0] * (pc - pf);
    qf = hcos_8[1] * (pd - pe);

    p0 = q0 + q1;
    p1 = hcos_4 * (q0 - q1);
    p2 = q2 + q3;
    p3 = hcos_4 * (q2 - q3);
    p4 = q4 + q5;
    p5 = hcos_4 * (q4 - q5);
    p6 = q6 + q7;
    p7 = hcos_4 * (q6 - q7);
    p8 = q8 + q9;
    p9 = hcos_4 * (q8 - q9);
    pa = qa + qb;
    pb = hcos_4 * (qa - qb);
    pc = qc + qd;
    pd = hcos_4 * (qc - qd);
    pe = qe + qf;
    pf = hcos_4 * (qe - qf);

    {
	REAL tmp;

	tmp = p6 + p7;
	OUT2(36) = -(p5 + tmp);
	OUT2(44) = -(p4 + tmp);
	tmp = pb + pf;
	OUT1(10, tmp);
	OUT1(6, pd + tmp);
	tmp = pe + pf;
	OUT2(46) = -(p8 + pc + tmp);
	OUT2(34) = -(p9 + pd + tmp);
	tmp += pa + pb;
	OUT2(38) = -(pd + tmp);
	OUT2(42) = -(pc + tmp);
	OUT1(2, p9 + pd + pf);
	OUT1(4, p5 + p7);
	OUT2(48) = -p0;
	out2[0] = -(out1[0] = p1);
	OUT1(8, p3);
	OUT1(12, p7);
	OUT1(14, pf);
	OUT2(40) = -(p2 + p3);
    }

    {
	register REAL *x = fraction;

	p0 = hcos_64[0] * (x[0] - x[31]);
	p1 = hcos_64[1] * (x[1] - x[30]);
	p2 = hcos_64[2] * (x[2] - x[29]);
	p3 = hcos_64[3] * (x[3] - x[28]);
	p4 = hcos_64[4] * (x[4] - x[27]);
	p5 = hcos_64[5] * (x[5] - x[26]);
	p6 = hcos_64[6] * (x[6] - x[25]);
	p7 = hcos_64[7] * (x[7] - x[24]);
	p8 = hcos_64[8] * (x[8] - x[23]);
	p9 = hcos_64[9] * (x[9] - x[22]);
	pa = hcos_64[10] * (x[10] - x[21]);
	pb = hcos_64[11] * (x[11] - x[20]);
	pc = hcos_64[12] * (x[12] - x[19]);
	pd = hcos_64[13] * (x[13] - x[18]);
	pe = hcos_64[14] * (x[14] - x[17]);
	pf = hcos_64[15] * (x[15] - x[16]);
    }

    q0 = p0 + pf;
    q1 = p1 + pe;
    q2 = p2 + pd;
    q3 = p3 + pc;
    q4 = p4 + pb;
    q5 = p5 + pa;
    q6 = p6 + p9;
    q7 = p7 + p8;
    q8 = hcos_32[0] * (p0 - pf);
    q9 = hcos_32[1] * (p1 - pe);
    qa = hcos_32[2] * (p2 - pd);
    qb = hcos_32[3] * (p3 - pc);
    qc = hcos_32[4] * (p4 - pb);
    qd = hcos_32[5] * (p5 - pa);
    qe = hcos_32[6] * (p6 - p9);
    qf = hcos_32[7] * (p7 - p8);

    p0 = q0 + q7;
    p1 = q1 + q6;
    p2 = q2 + q5;
    p3 = q3 + q4;
    p4 = hcos_16[0] * (q0 - q7);
    p5 = hcos_16[1] * (q1 - q6);
    p6 = hcos_16[2] * (q2 - q5);
    p7 = hcos_16[3] * (q3 - q4);
    p8 = q8 + qf;
    p9 = q9 + qe;
    pa = qa + qd;
    pb = qb + qc;
    pc = hcos_16[0] * (q8 - qf);
    pd = hcos_16[1] * (q9 - qe);
    pe = hcos_16[2] * (qa - qd);
    pf = hcos_16[3] * (qb - qc);

    q0 = p0 + p3;
    q1 = p1 + p2;
    q2 = hcos_8[0] * (p0 - p3);
    q3 = hcos_8[1] * (p1 - p2);
    q4 = p4 + p7;
    q5 = p5 + p6;
    q6 = hcos_8[0] * (p4 - p7);
    q7 = hcos_8[1] * (p5 - p6);
    q8 = p8 + pb;
    q9 = p9 + pa;
    qa = hcos_8[0] * (p8 - pb);
    qb = hcos_8[1] * (p9 - pa);
    qc = pc + pf;
    qd = pd + pe;
    qe = hcos_8[0] * (pc - pf);
    qf = hcos_8[1] * (pd - pe);

    p0 = q0 + q1;
    p1 = hcos_4 * (q0 - q1);
    p2 = q2 + q3;
    p3 = hcos_4 * (q2 - q3);
    p4 = q4 + q5;
    p5 = hcos_4 * (q4 - q5);
    p6 = q6 + q7;
    p7 = hcos_4 * (q6 - q7);
    p8 = q8 + q9;
    p9 = hcos_4 * (q8 - q9);
    pa = qa + qb;
    pb = hcos_4 * (qa - qb);
    pc = qc + qd;
    pd = hcos_4 * (qc - qd);
    pe = qe + qf;
    pf = hcos_4 * (qe - qf);

    {
	REAL tmp;

	tmp = pd + pf;
	OUT1(5, p5 + p7 + pb + tmp);
	tmp += p9;
	OUT1(1, p1 + tmp);
	OUT2(33) = -(p1 + pe + tmp);
	tmp += p5 + p7;
	OUT1(3, tmp);
	OUT2(35) = -(p6 + pe + tmp);
	tmp = pa + pb + pc + pd + pe + pf;
	OUT2(39) = -(p2 + p3 + tmp - pc);
	OUT2(43) = -(p4 + p6 + p7 + tmp - pd);
	OUT2(37) = -(p5 + p6 + p7 + tmp - pc);
	OUT2(41) = -(p2 + p3 + tmp - pd);
	tmp = p8 + pc + pe + pf;
	OUT2(47) = -(p0 + tmp);
	OUT2(45) = -(p4 + p6 + p7 + tmp);
	tmp = pb + pf;
	OUT1(11, p7 + tmp);
	tmp += p3;
	OUT1(9, tmp);
	OUT1(7, pd + tmp);
	OUT1(13, p7 + pf);
	OUT1(15, pf);
    }
}


#ifdef FIXED_POINT
#define RAW( r )  (r.x>>(FIXED_POINT_FRACBITS-15))
#else
#define RAW( r )  (int)(r*scalefactor)
#endif

#define SAVE \
	raw=RAW(r); \
	if(raw>MAXSCALE)raw=MAXSCALE; \
	if(raw<MINSCALE)raw=MINSCALE; \
	putraw(raw);
#define OS  r=*vp * *dp++
#define XX  vp+=15;r+=*vp * *dp++
#define OP  r+=*--vp * *dp++

inline void
Mpegtoraw::generatesingle(void)
{
    int i;
    REAL r;
    register REAL *vp;
    register const REAL *dp;
    int raw;

    i = 32;
    dp = filter;
    vp = calcbufferL[currentcalcbuffer] + calcbufferoffset;
// actual_v+actual_write_pos;

#if 0
    switch (calcbufferoffset) {
    case 0:
	for (; i; i--, vp += 15) {
	    OS;
	    XX;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    SAVE;
	}
	break;
    case 1:
	for (; i; i--, vp += 15) {
	    OS;
	    OP;
	    XX;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    SAVE;
	}
	break;
    case 2:
	for (; i; i--, vp += 15) {
	    OS;
	    OP;
	    OP;
	    XX;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    SAVE;
	}
	break;
    case 3:
	for (; i; i--, vp += 15) {
	    OS;
	    OP;
	    OP;
	    OP;
	    XX;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    SAVE;
	}
	break;
    case 4:
	for (; i; i--, vp += 15) {
	    OS;
	    OP;
	    OP;
	    OP;
	    OP;
	    XX;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    SAVE;
	}
	break;
    case 5:
	for (; i; i--, vp += 15) {
	    OS;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    XX;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    SAVE;
	}
	break;
    case 6:
	for (; i; i--, vp += 15) {
	    OS;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    XX;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    SAVE;
	}
	break;
    case 7:
	for (; i; i--, vp += 15) {
	    OS;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    XX;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    SAVE;
	}
	break;
    case 8:
	for (; i; i--, vp += 15) {
	    OS;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    XX;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    SAVE;
	}
	break;
    case 9:
	for (; i; i--, vp += 15) {
	    OS;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    XX;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    SAVE;
	}
	break;
    case 10:
	for (; i; i--, vp += 15) {
	    OS;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    XX;
	    OP;
	    OP;
	    OP;
	    OP;
	    SAVE;
	}
	break;
    case 11:
	for (; i; i--, vp += 15) {
	    OS;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    XX;
	    OP;
	    OP;
	    OP;
	    SAVE;
	}
	break;
    case 12:
	for (; i; i--, vp += 15) {
	    OS;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    XX;
	    OP;
	    OP;
	    SAVE;
	}
	break;
    case 13:
	for (; i; i--, vp += 15) {
	    OS;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    OP;
	    XX;
	    OP;
	    SAVE;
	}
	break;
    case 14:
	for (; i; i--, vp += 15) {
	    OS;
	    OP;
	    OP;
	    OP;
	    OP;