mpeglayer3mktables.cc

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// mpeglayer3mktables.cc
// (C) 1999 Nicolas Pitre <[e-mail]>
//
// This code generate the mpeglayer3tables.h file
//
// To compile: gcc -Wall -O2 -o mk mpeglayer3mktables.cc -lm
// To build the table: ./mk
#include <math.h>
#include <stdio.h>
#define OUT_FNAME "mpeglayer3tables.h"
typedef double REAL;

#define PI     M_PI
#define PI_12  (PI/12.0)
#define PI_18  (PI/18.0)
#define PI_24  (PI/24.0)
#define PI_36  (PI/36.0)
#define PI_72  (PI/72.0)

#define FOURTHIRDSTABLENUMBER (1<<13)

static REAL two_to_negative_half_pow[40];
static REAL TO_FOUR_THIRDSTABLE[FOURTHIRDSTABLENUMBER];
static REAL POW2[256];
static REAL POW2_1[8][2][16];
static REAL ca[8], cs[8];

static REAL win[4][36];
static REAL cos_18[9];
static REAL hsec_36[9], hsec_12[3];

REAL cos1_6 = cos(PI / 6.0 * 1.0);
REAL cos2_6 = cos(PI / 6.0 * 2.0);

typedef struct
{
    REAL l, r;
}
RATIOS;

static RATIOS rat_1[16], rat_2[2][64];



int
main(void)
{
    /* code for computing all tables */
    int i, j, k;

    // Calculate win
    {
	for (i = 0; i < 18; i++)
	    win[0][i] = win[1][i] =
		0.5 * sin(PI_72 * (double) (2 * i + 1)) / cos(PI_72 *
							      (double) (2 *
									i +
									19));
	for (; i < 36; i++)
	    win[0][i] = win[3][i] =
		0.5 * sin(PI_72 * (double) (2 * i + 1)) / cos(PI_72 *
							      (double) (2 *
									i +
									19));

	for (i = 0; i < 6; i++) {
	    win[1][i + 18] = 0.5 / cos(PI_72 * (double) (2 * (i + 18) + 19));
	    win[3][i + 12] = 0.5 / cos(PI_72 * (double) (2 * (i + 12) + 19));
	    win[1][i + 24] =
		0.5 * sin(PI_24 * (double) (2 * i + 13)) / cos(PI_72 *
							       (double) (2 *
									 (i +
									  24)
									 +
									 19));
	    win[1][i + 30] = win[3][i] = 0.0;
	    win[3][i + 6] =
		0.5 * sin(PI_24 * (double) (2 * i + 1)) / cos(PI_72 *
							      (double) (2 *
									(i +
									 6) +
									19));
	}
	for (i = 0; i < 12; i++)
	    win[2][i] =
		0.5 * sin(PI_24 * (double) (2 * i + 1)) / cos(PI_24 *
							      (double) (2 *
									i +
									7));
    }

    for (i = 0; i < 9; i++)
	cos_18[i] = cos(PI_18 * double (i));
    for (i = 0; i < 9; i++)
	hsec_36[i] = 0.5 / cos(PI_36 * double (i * 2 + 1));
    for (i = 0; i < 3; i++)
	hsec_12[i] = 0.5 / cos(PI_12 * double (i * 2 + 1));

    for (i = 0; i < 40; i++)
	two_to_negative_half_pow[i] = (REAL) pow(2.0, -0.5 * (double) i);

    for (i = 0; i < FOURTHIRDSTABLENUMBER; i++)
	TO_FOUR_THIRDSTABLE[i] = (REAL) pow((double) i, 4.0 / 3.0);
    for (i = 0; i < 256; i++)
	POW2[i] = (REAL) pow(2.0, (0.25 * (i - 210.0)));
    for (i = 0; i < 8; i++)
	for (j = 0; j < 2; j++)
	    for (k = 0; k < 16; k++)
		POW2_1[i][j][k] =
		    pow(2.0, (-2.0 * i) - (0.5 * (1.0 + j) * k));

    {
	static REAL TAN12[16] = { 0.0, 0.26794919, 0.57735027, 1.0,
	    1.73205081, 3.73205081, 9.9999999e10, -3.73205081,
	    -1.73205081, -1.01, -0.57735027, -0.26794919,
	    0.0, 0.26794919, 0.57735027, 1.0
	};

	for (i = 0; i < 16; i++) {
	    rat_1[i].l = TAN12[i] / (1.0 + TAN12[i]);
	    rat_1[i].r = 1.0 / (1.0 + TAN12[i]);
	}
    }

#define IO0 ((double)0.840896415256)
#define IO1 ((double)0.707106781188)
    rat_2[0][0].l = rat_2[0][0].r = rat_2[1][0].l = rat_2[1][0].r = 1.;

    for (i = 1; i < 64; i++)
	if ((i % 2) == 1) {
	    rat_2[0][i].l = pow(IO0, (i + 1) / 2);
	    rat_2[1][i].l = pow(IO1, (i + 1) / 2);
	    rat_2[0][i].r = rat_2[1][i].r = 1.;
	} else {
	    rat_2[0][i].l = rat_2[1][i].l = 1.;
	    rat_2[0][i].r = pow(IO0, i / 2);
	    rat_2[1][i].r = pow(IO1, i / 2);
	}

    {
	static REAL Ci[8] =
	    { -0.6f, -0.535f, -0.33f, -0.185f, -0.095f, -0.041f, -0.0142f,
-0.0037f };
	REAL sq;

	for (i = 0; i < 8; i++) {
	    sq = sqrt(1.0f + Ci[i] * Ci[i]);
	    cs[i] = 1.0f / sq;
	    ca[i] = Ci[i] * cs[i];
	}
    }


    /* now print out those tables to the appropriate file */

    FILE *out = fopen(OUT_FNAME, "w");
    if (!out) {
	perror(OUT_FNAME);
	exit(-1);
    }
    fprintf(out, "// " OUT_FNAME "\n");
    fprintf(out, "// It is included by mpeglayer3.cc\n");
    fprintf(out, "// This file was generated using mpeglayer3mktables.cc\n");
    fprintf(out,
	    "// Do not edit this file but mpeglayer3mktables.cc instead\n\n\n");

    fprintf(out, "#include <values.h>\n");
    fprintf(out, "#ifndef FIXED_POINT\n");
    fprintf(out, "#define X( x )  (x)\n");
    fprintf(out, "#define inf  MAXFLOAT\n");
    fprintf(out, "#define Inf  MAXFLOAT\n");
    fprintf(out, "#else\n");
    fprintf(out, "#define inf  MAXINT\n");
    fprintf(out, "#define Inf  MAXINT\n");
    fprintf(out, "#endif\n\n\n");

    int s;
    static char sp[] = "   ";


#define TABLE( DECL, I, J, K, FMT, WRAP, VAL... ) \
  fprintf( out, "static const " DECL " =\n{\n" ); \
  s = 0; \
  i = 0; \
  do{ \
    if( I ){ \
      s++; \
      fprintf( out, "%s{\n", sp+3-s ); \
    } \
    j = 0; \
    do{ \
      if( J ){ \
        s++; \
        fprintf( out, "%s{\n", sp+3-s ); \
      } \
      k = 0; \
      do{ \
        if( (k % WRAP) == 0 ) fprintf( out, "%s", sp+3-s ); \
        fprintf( out, " "FMT, ##VAL ); \
        if( k < K-1 ) fprintf( out, "," ); \
        if( ((k+1) % WRAP) == 0 ) fprintf( out, "\n" ); \
      }while( ++k < K ); \
      if( J ){ \
        fprintf( out, "%s}\n", sp+3-s ); \
        if( j < J-1 ) fprintf( out, "%s,\n", sp+3-s ); \
        s--; \
      } \
    }while( ++j < J ); \
    if( I ){ \
      fprintf( out, "%s}\n", sp+3-s ); \
      if( i < I-1 ) fprintf( out, "%s,\n", sp+3-s ); \
      s--; \
    } \
  }while( ++i < I ); \
  fprintf( out, "};\n\n" );



    fprintf(out, "\n#ifdef FIXED_POINT\n");
    fprintf(out, "#undef X\n");
    fprintf(out, "#define X( x )  {FL2FIX( x, FIXED_POINT_FRACBITS )}\n");
    fprintf(out, "#endif\n\n");

    TABLE("REAL two_to_negative_half_pow[40]", 0, 0, 40,
	  "X(%.15f)", 4, two_to_negative_half_pow[k]);

    TABLE("REAL POW2_1[8][2][16]", 8, 2, 16, "X(%.15f)", 4, POW2_1[i][j][k]);

    TABLE("REAL ca[8]", 0, 0, 8, "X(%.15f)", 4, ca[k]);
    TABLE("REAL cs[8]", 0, 0, 8, "X(%.15f)", 4, cs[k]);

    TABLE("REAL win[4][36]", 0, 4, 36, "X(%.15f)", 4, win[j][k]);

    TABLE("REAL cos_18[9]", 0, 0, 9, "X(%.15f)", 3, cos_18[k]);

    TABLE("REAL hsec_36[9]", 0, 0, 9, "X(%.15f)", 3, hsec_36[k]);

    TABLE("REAL hsec_12[3]", 0, 0, 3, "X(%.15f)", 3, hsec_12[k]);

    TABLE("RATIOS rat_1[16]", 0, 0, 16, "{X(% .15f), X(% .15f)}", 2,
	  rat_1[k].l, rat_1[k].r);
    TABLE("RATIOS rat_2[2][64]", 0, 2, 64, "{X(%.15f), X(%.15f)}", 2,
	  rat_2[j][k].l, rat_2[j][k].r);


    fprintf(out, "\n#ifdef FIXED_POINT\n");
    fprintf(out, "#undef X\n");
    fprintf(out, "#define X( x )  {FL2FIX( x, 19 )}\n");
    fprintf(out, "#endif\n\n");

    TABLE("REAL19 POW2[256]", 0, 0, 256, "X(%.15f)", 4, POW2[k]);


    fprintf(out, "\n#ifdef FIXED_POINT\n");
    fprintf(out, "#undef X\n");
    fprintf(out, "#define X( x )  {FL2FIX( x, 13 )}\n");
    fprintf(out, "#endif\n\n");

    TABLE("REAL13 TO_FOUR_THIRDSTABLE[FOURTHIRDSTABLENUMBER]",
	  0, 0, FOURTHIRDSTABLENUMBER, "X(%17.9f)", 4,
	  TO_FOUR_THIRDSTABLE[k]);

    fprintf(out, "#define cos1_6  %.15f\n", cos1_6);
    fprintf(out, "#define cos2_6  %.15f\n", cos2_6);
    fprintf(out, "\n");

    fclose(out);
    printf("File " OUT_FNAME " written.\n");

    return 0;
}