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author | Matthias P. Braendli <matthias.braendli@mpb.li> | 2016-02-15 02:44:20 +0100 |
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committer | Matthias P. Braendli <matthias.braendli@mpb.li> | 2016-02-15 02:44:20 +0100 |
commit | 22f1fce330059ef8a383cf327a023d6a9da5ad3e (patch) | |
tree | 6893f158dcaaaa1b9f1317923c32a841ba31f768 /libtoolame-dab/pds_subband.c | |
parent | 891bb2592944aa2be2d81e1583e73e632e70537f (diff) | |
download | ODR-AudioEnc-22f1fce330059ef8a383cf327a023d6a9da5ad3e.tar.gz ODR-AudioEnc-22f1fce330059ef8a383cf327a023d6a9da5ad3e.tar.bz2 ODR-AudioEnc-22f1fce330059ef8a383cf327a023d6a9da5ad3e.zip |
Include toolame-dab as library
Diffstat (limited to 'libtoolame-dab/pds_subband.c')
-rw-r--r-- | libtoolame-dab/pds_subband.c | 361 |
1 files changed, 361 insertions, 0 deletions
diff --git a/libtoolame-dab/pds_subband.c b/libtoolame-dab/pds_subband.c new file mode 100644 index 0000000..04938c4 --- /dev/null +++ b/libtoolame-dab/pds_subband.c @@ -0,0 +1,361 @@ +#include "common.h" +#include "encoder.h" + +void IDCT32 (double *, double *, int); + +/*********************************************************************** + An implementation of a modified window subband as seen in Kumar & Zubair's +"A high performance software implentation of mpeg audio encoder" +I think from IEEE ASCAP 1996 proceedings + +input: shift in 32*12 (384) new samples into a 864 point buffer. +ch - which channel we're looking at. + +This routine basically does 12 calls to window subband all in one go. +Not yet called in code. here for testing only. +************************************************************************/ +#define NEWWS +void window_subband12 (short **buffer, int ch) +{ + static double x[2][864]; /* 2 channels, 864 buffer for each */ + double *xk; + double t[12]; /* a temp buffer for summing values */ + double y[12][64]; /* 12 output arrays of 64 values */ + int i, j, k, m; + static double c[512]; /* enwindow array */ + static int init = 0; + double c0; + + if (!init) { + read_ana_window (c); + printf ("done init\n"); + init++; + } + + xk = x[ch]; /* an easier way of referencing the array */ + + /* shift 384 new samples into the buffer */ + for (i = 863; i >= 384; i--) + xk[i] = xk[i - 384]; + for (i = 383; i >= 0; i--) + xk[i] = (double) *(*buffer)++ / SCALE; + + for (j = 0; j < 64; j++) { + for (k = 0; k < 12; k++) + t[k] = 0; + for (i = 0; i < 8; i++) { + m = i * 64 + j; + c0 = c[m]; + t[0] += c0 * xk[m + 352]; + t[1] += c0 * xk[m + 320]; + t[2] += c0 * xk[m + 288]; + t[3] += c0 * xk[m + 256]; + t[4] += c0 * xk[m + 224]; + t[5] += c0 * xk[m + 192]; + t[6] += c0 * xk[m + 160]; + t[7] += c0 * xk[m + 128]; + t[8] += c0 * xk[m + 96]; + t[9] += c0 * xk[m + 64]; + t[10] += c0 * xk[m + 32]; + t[11] += c0 * xk[m]; + } + for (i = 0; i < 12; i++) { + y[i][j] = t[i]; + } + } +#define DB1x +#ifdef DB1 + for (i = 0; i < 12; i++) { + printf ("--%i--\n", i); + for (j = 0; j < 64; j++) { + printf ("%f\t", y[i][j]); + if ((j + 1) % 4 == 0) + printf ("\n"); + } + } + exit (0); +#endif +} + + +/************************************************************************/ +/* +/* read_ana_window() +/* +/* PURPOSE: Reads encoder window file "enwindow" into array #ana_win# +/* +/************************************************************************/ + +void read_ana_window (ana_win) + double ana_win[HAN_SIZE]; +{ + int i, j[4]; + FILE *fp; + double f[4]; + char t[150]; + + if (!(fp = OpenTableFile ("enwindow"))) { + printf ("Please check analysis window table 'enwindow'\n"); + exit (1); + } + for (i = 0; i < 512; i += 4) { + fgets (t, 150, fp); + sscanf (t, "C[%d] = %lf C[%d] = %lf C[%d] = %lf C[%d] = %lf\n", j, f, + j + 1, f + 1, j + 2, f + 2, j + 3, f + 3); + if (i == j[0]) { + ana_win[i] = f[0]; + ana_win[i + 1] = f[1]; + ana_win[i + 2] = f[2]; + ana_win[i + 3] = f[3]; + } else { + printf ("Check index in analysis window table\n"); + exit (1); + } + fgets (t, 150, fp); + } + fclose (fp); +} + +/************************************************************************/ +/* +/* window_subband() +/* +/* PURPOSE: Overlapping window on PCM samples +/* +/* SEMANTICS: +/* 32 16-bit pcm samples are scaled to fractional 2's complement and +/* concatenated to the end of the window buffer #x#. The updated window +/* buffer #x# is then windowed by the analysis window #c# to produce the +/* windowed sample #z# +/* +/************************************************************************/ +#ifdef COMBWS +void window_subband (short **buffer, double s[SBLIMIT], int k, int sblimit) +{ + typedef double XX[2][HAN_SIZE]; + static XX *x; + double *xk; + int i; + static int off[2] = { 0, 0 }; + static char init = 0; + double t; + static double enwindow[512]; + double *ep0, *ep1, *ep2, *ep3, *ep4, *ep5, *ep6, *ep7; + double z[64]; + double yprime[32]; + if (!init) { + read_ana_window (enwindow); + x = (XX *) mem_alloc (sizeof (XX), "x"); + memset (x, 0, 2 * HAN_SIZE * sizeof (double)); + init = 1; + } + xk = (*x)[k]; + + /* replace 32 oldest samples with 32 new samples */ + for (i = 0; i < 32; i++) + xk[31 - i + off[k]] = (double) *(*buffer)++ / SCALE; + + ep0 = &enwindow[0]; + ep1 = &enwindow[64]; + ep2 = &enwindow[128]; + ep3 = &enwindow[192]; + ep4 = &enwindow[256]; + ep5 = &enwindow[320]; + ep6 = &enwindow[384]; + ep7 = &enwindow[448]; + + /* shift samples into proper window positions */ + for (i = 0; i < 64; i++) { + t = xk[(i + off[k]) & (512 - 1)] * *ep0++; + t += xk[(i + 64 + off[k]) & (512 - 1)] * *ep1++; + t += xk[(i + 128 + off[k]) & (512 - 1)] * *ep2++; + t += xk[(i + 192 + off[k]) & (512 - 1)] * *ep3++; + t += xk[(i + 256 + off[k]) & (512 - 1)] * *ep4++; + t += xk[(i + 320 + off[k]) & (512 - 1)] * *ep5++; + t += xk[(i + 384 + off[k]) & (512 - 1)] * *ep6++; + t += xk[(i + 448 + off[k]) & (512 - 1)] * *ep7++; + z[i] = t; + } + + off[k] += 480; /*offset is modulo (HAN_SIZE-1) */ + off[k] &= HAN_SIZE - 1; + + yprime[0] = z[16]; + for (i = 1; i <= 16; i++) + yprime[i] = z[i + 16] + z[16 - i]; + for (i = 17; i <= 31; i++) + yprime[i] = z[i + 16] - z[80 - i]; + IDCT32 (yprime, s, sblimit); + /* filter_subband (z,s); */ +} +#else +void window_subband (short **buffer, double z[64], int k) +{ + typedef double XX[2][HAN_SIZE]; + static XX *x; + double *xk; + int i; + static int off[2] = { 0, 0 }; + static char init = 0; + double t; + static double enwindow[512]; + double *ep0, *ep1, *ep2, *ep3, *ep4, *ep5, *ep6, *ep7; + if (!init) { + read_ana_window (enwindow); + x = (XX *) mem_alloc (sizeof (XX), "x"); + memset (x, 0, 2 * HAN_SIZE * sizeof (double)); + init = 1; + } + xk = (*x)[k]; + + /* replace 32 oldest samples with 32 new samples */ + /* PDS old code: */ + /* for (i=0;i<32;i++) + xk[31-i+off[k]] = (double) *(*buffer)++/SCALE; + */ + { + register double *xk_t = xk + off[k]; + for (i = 32; i--;) + xk_t[i] = (double) *(*buffer)++; + } + + ep0 = &enwindow[0]; + ep1 = &enwindow[64]; + ep2 = &enwindow[128]; + ep3 = &enwindow[192]; + ep4 = &enwindow[256]; + ep5 = &enwindow[320]; + ep6 = &enwindow[384]; + ep7 = &enwindow[448]; + + /* shift samples into proper window positions */ + for (i = 0; i < 64; i++) { + t = xk[(i + off[k]) & (512 - 1)] * *ep0++; + t += xk[(i + 64 + off[k]) & (512 - 1)] * *ep1++; + t += xk[(i + 128 + off[k]) & (512 - 1)] * *ep2++; + t += xk[(i + 192 + off[k]) & (512 - 1)] * *ep3++; + t += xk[(i + 256 + off[k]) & (512 - 1)] * *ep4++; + t += xk[(i + 320 + off[k]) & (512 - 1)] * *ep5++; + t += xk[(i + 384 + off[k]) & (512 - 1)] * *ep6++; + t += xk[(i + 448 + off[k]) & (512 - 1)] * *ep7++; + z[i] = t; + } + + off[k] += 480; /*offset is modulo (HAN_SIZE-1) */ + off[k] &= HAN_SIZE - 1; + +} +#endif +/************************************************************************/ +/* +/* create_ana_filter() +/* +/* PURPOSE: Calculates the analysis filter bank coefficients +/* +/* SEMANTICS: +/* Calculates the analysis filterbank coefficients and rounds to the +/* 9th decimal place accuracy of the filterbank tables in the ISO +/* document. The coefficients are stored in #filter# +/* +/************************************************************************/ + +void create_ana_filter (filter) + double filter[SBLIMIT][64]; +{ + register int i, k; + + for (i = 0; i < 32; i++) + for (k = 0; k < 64; k++) { + if ((filter[i][k] = + 1e9 * cos ((double) ((2 * i + 1) * (16 - k) * PI64))) >= 0) + modf (filter[i][k] + 0.5, &filter[i][k]); + else + modf (filter[i][k] - 0.5, &filter[i][k]); + filter[i][k] *= 1e-9; + } +} + +/************************************************************************ +* +* filter_subband() +* +* PURPOSE: Calculates the analysis filter bank coefficients +* +* SEMANTICS: +* The windowed samples #z# is filtered by the digital filter matrix #m# +* to produce the subband samples #s#. This done by first selectively +* picking out values from the windowed samples, and then multiplying +* them by the filter matrix, producing 32 subband samples. +* +************************************************************************/ +void create_dct_matrix (filter) + double filter[16][32]; +{ + register int i, k; + + for (i = 0; i < 16; i++) + for (k = 0; k < 32; k++) { + if ((filter[i][k] = 1e9 * cos ((double) ((2 * i + 1) * k * PI64))) >= 0) + modf (filter[i][k] + 0.5, &filter[i][k]); + else + modf (filter[i][k] - 0.5, &filter[i][k]); + filter[i][k] *= 1e-9; + filter[i][k] /= (double) SCALE; /* PDS */ + } + /* PDS this code could/should be replaced; use simple cos */ + /* and don't do additional rounding ??? See LAME(e.g.3.34) */ +} + +void IDCT32 (xin, xout, sblimit) + double *xin, *xout; + int sblimit; +{ + int i, j; + double s0, s1; + typedef double MM[16][32]; + static MM *m = 0; + if (m == 0) { + m = (MM *) mem_alloc (sizeof (MM), "filter"); + create_dct_matrix (*m); + } + /* Only compute subband filter info for frequency ranges which */ + /* will be really needed/encoded later. Code is "general", but */ + /* only produces speed up in low qual/bps coding situations. */ + /* Added/adapted by PDS Oct 1999. */ + for (i = ((sblimit > 16) ? SBLIMIT - sblimit : sblimit); i--;) { + s0 = 0.0; + for (j = 0; j < 32; j++) { + s0 += (*m)[i][j] * xin[j + 0]; + } + xout[i] = s0; + } + for (i = SBLIMIT - sblimit; i < 16; i++) { + s0 = s1 = 0.0; + for (j = 0; j < 32; j += 2) { + s0 += (*m)[i][j] * xin[j]; + s1 += (*m)[i][j + 1] * xin[j + 1]; + } + xout[i] = s0 + s1; + xout[31 - i] = s0 - s1; + } + /* PDS TODO: use pointers instead of arrays ??? */ + /* PDS TODO: is '--' j loop faster then original */ + /* code: ' for( j=0; j<32; j+=2 ) { ... } ' ? */ +} + +void filter_subband (z, s, sblimit) + double z[HAN_SIZE], s[SBLIMIT]; + int sblimit; +{ + double yprime[32]; + int i, j; + + { + yprime[0] = z[16]; + for (i = 1; i <= 16; i++) + yprime[i] = z[i + 16] + z[16 - i]; + for (i = 17; i <= 31; i++) + yprime[i] = z[i + 16] - z[80 - i]; + IDCT32 (yprime, s, sblimit); + } +} |