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-rw-r--r--src/libac3/coeff.c437
1 files changed, 437 insertions, 0 deletions
diff --git a/src/libac3/coeff.c b/src/libac3/coeff.c
new file mode 100644
index 000000000..6c95f74a5
--- /dev/null
+++ b/src/libac3/coeff.c
@@ -0,0 +1,437 @@
+/*
+ * coeff.c
+ *
+ * Copyright (C) Aaron Holtzman - May 1999
+ *
+ * This file is part of ac3dec, a free Dolby AC-3 stream decoder.
+ *
+ * ac3dec 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, or (at your option)
+ * any later version.
+ *
+ * ac3dec 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 GNU Make; see the file COPYING. If not, write to
+ * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <stdlib.h>
+#include <stdio.h>
+#include "ac3.h"
+#include "ac3_internal.h"
+
+
+#include "bitstream.h"
+#include "dither.h"
+#include "coeff.h"
+
+//
+//Lookup tables of 0.15 two's complement quantization values
+//
+#define Q0 ((-2 << 15) / 3.0)
+#define Q1 (0)
+#define Q2 ((2 << 15) / 3.0)
+
+static const float q_1_0[ 32 ] =
+{
+ Q0,Q0,Q0,Q0,Q0,Q0,Q0,Q0,Q0,
+ Q1,Q1,Q1,Q1,Q1,Q1,Q1,Q1,Q1,
+ Q2,Q2,Q2,Q2,Q2,Q2,Q2,Q2,Q2,
+ 0,0,0,0,0
+};
+
+static const float q_1_1[ 32 ] =
+{
+ Q0,Q0,Q0,Q1,Q1,Q1,Q2,Q2,Q2,
+ Q0,Q0,Q0,Q1,Q1,Q1,Q2,Q2,Q2,
+ Q0,Q0,Q0,Q1,Q1,Q1,Q2,Q2,Q2,
+ 0,0,0,0,0
+};
+
+static const float q_1_2[ 32 ] =
+{
+ Q0,Q1,Q2,Q0,Q1,Q2,Q0,Q1,Q2,
+ Q0,Q1,Q2,Q0,Q1,Q2,Q0,Q1,Q2,
+ Q0,Q1,Q2,Q0,Q1,Q2,Q0,Q1,Q2,
+ 0,0,0,0,0
+};
+
+#undef Q0
+#undef Q1
+#undef Q2
+
+#define Q0 ((-4 << 15) / 5.0)
+#define Q1 ((-2 << 15) / 5.0)
+#define Q2 (0)
+#define Q3 ((2 << 15) / 5.0)
+#define Q4 ((4 << 15) / 5.0)
+
+static const float q_2_0[ 128 ] =
+{
+ Q0,Q0,Q0,Q0,Q0,Q0,Q0,Q0,Q0,Q0,Q0,Q0,
+ Q0,Q0,Q0,Q0,Q0,Q0,Q0,Q0,Q0,Q0,Q0,Q0,Q0,
+ Q1,Q1,Q1,Q1,Q1,Q1,Q1,Q1,Q1,Q1,Q1,Q1,
+ Q1,Q1,Q1,Q1,Q1,Q1,Q1,Q1,Q1,Q1,Q1,Q1,Q1,
+ Q2,Q2,Q2,Q2,Q2,Q2,Q2,Q2,Q2,Q2,Q2,Q2,
+ Q2,Q2,Q2,Q2,Q2,Q2,Q2,Q2,Q2,Q2,Q2,Q2,Q2,
+ Q3,Q3,Q3,Q3,Q3,Q3,Q3,Q3,Q3,Q3,Q3,Q3,
+ Q3,Q3,Q3,Q3,Q3,Q3,Q3,Q3,Q3,Q3,Q3,Q3,Q3,
+ Q4,Q4,Q4,Q4,Q4,Q4,Q4,Q4,Q4,Q4,Q4,Q4,
+ Q4,Q4,Q4,Q4,Q4,Q4,Q4,Q4,Q4,Q4,Q4,Q4,Q4,
+ 0,0,0
+};
+
+static const float q_2_1[ 128 ] =
+{
+ Q0,Q0,Q0,Q0,Q0,Q1,Q1,Q1,Q1,Q1,
+ Q2,Q2,Q2,Q2,Q2,Q3,Q3,Q3,Q3,Q3,
+ Q4,Q4,Q4,Q4,Q4,Q0,Q0,Q0,Q0,Q0,
+ Q1,Q1,Q1,Q1,Q1,Q2,Q2,Q2,Q2,Q2,
+ Q3,Q3,Q3,Q3,Q3,Q4,Q4,Q4,Q4,Q4,
+ Q0,Q0,Q0,Q0,Q0,Q1,Q1,Q1,Q1,Q1,
+ Q2,Q2,Q2,Q2,Q2,Q3,Q3,Q3,Q3,Q3,
+ Q4,Q4,Q4,Q4,Q4,Q0,Q0,Q0,Q0,Q0,
+ Q1,Q1,Q1,Q1,Q1,Q2,Q2,Q2,Q2,Q2,
+ Q3,Q3,Q3,Q3,Q3,Q4,Q4,Q4,Q4,Q4,
+ Q0,Q0,Q0,Q0,Q0,Q1,Q1,Q1,Q1,Q1,
+ Q2,Q2,Q2,Q2,Q2,Q3,Q3,Q3,Q3,Q3,
+ Q4,Q4,Q4,Q4,Q4,0,0,0
+ };
+
+static const float q_2_2[ 128 ] =
+ {
+ Q0,Q1,Q2,Q3,Q4,Q0,Q1,Q2,Q3,Q4,
+ Q0,Q1,Q2,Q3,Q4,Q0,Q1,Q2,Q3,Q4,
+ Q0,Q1,Q2,Q3,Q4,Q0,Q1,Q2,Q3,Q4,
+ Q0,Q1,Q2,Q3,Q4,Q0,Q1,Q2,Q3,Q4,
+ Q0,Q1,Q2,Q3,Q4,Q0,Q1,Q2,Q3,Q4,
+ Q0,Q1,Q2,Q3,Q4,Q0,Q1,Q2,Q3,Q4,
+ Q0,Q1,Q2,Q3,Q4,Q0,Q1,Q2,Q3,Q4,
+ Q0,Q1,Q2,Q3,Q4,Q0,Q1,Q2,Q3,Q4,
+ Q0,Q1,Q2,Q3,Q4,Q0,Q1,Q2,Q3,Q4,
+ Q0,Q1,Q2,Q3,Q4,Q0,Q1,Q2,Q3,Q4,
+ Q0,Q1,Q2,Q3,Q4,Q0,Q1,Q2,Q3,Q4,
+ Q0,Q1,Q2,Q3,Q4,Q0,Q1,Q2,Q3,Q4,
+ Q0,Q1,Q2,Q3,Q4,0,0,0
+};
+
+#undef Q0
+#undef Q1
+#undef Q2
+#undef Q3
+#undef Q4
+
+static const float q_3[7] =
+{
+ (-6 << 15)/7.0, (-4 << 15)/7.0, (-2 << 15)/7.0, 0.0,
+ ( 2 << 15)/7.0, ( 4 << 15)/7.0, ( 6 << 15)/7.0
+};
+
+#define Q0 ((-10 << 15) / 11.0)
+#define Q1 ((-8 << 15) / 11.0)
+#define Q2 ((-6 << 15) / 11.0)
+#define Q3 ((-4 << 15) / 11.0)
+#define Q4 ((-2 << 15) / 11.0)
+#define Q5 (0)
+#define Q6 ((2 << 15) / 11.0)
+#define Q7 ((4 << 15) / 11.0)
+#define Q8 ((6 << 15) / 11.0)
+#define Q9 ((8 << 15) / 11.0)
+#define QA ((10 << 15) / 11.0)
+
+static const float q_4_0[ 128 ] =
+{
+ Q0, Q0, Q0, Q0, Q0, Q0, Q0, Q0, Q0, Q0, Q0,
+ Q1, Q1, Q1, Q1, Q1, Q1, Q1, Q1, Q1, Q1, Q1,
+ Q2, Q2, Q2, Q2, Q2, Q2, Q2, Q2, Q2, Q2, Q2,
+ Q3, Q3, Q3, Q3, Q3, Q3, Q3, Q3, Q3, Q3, Q3,
+ Q4, Q4, Q4, Q4, Q4, Q4, Q4, Q4, Q4, Q4, Q4,
+ Q5, Q5, Q5, Q5, Q5, Q5, Q5, Q5, Q5, Q5, Q5,
+ Q6, Q6, Q6, Q6, Q6, Q6, Q6, Q6, Q6, Q6, Q6,
+ Q7, Q7, Q7, Q7, Q7, Q7, Q7, Q7, Q7, Q7, Q7,
+ Q8, Q8, Q8, Q8, Q8, Q8, Q8, Q8, Q8, Q8, Q8,
+ Q9, Q9, Q9, Q9, Q9, Q9, Q9, Q9, Q9, Q9, Q9,
+ QA, QA, QA, QA, QA, QA, QA, QA, QA, QA, QA,
+ 0, 0, 0, 0, 0, 0, 0
+ };
+
+static const float q_4_1[ 128 ] =
+{
+ Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7, Q8, Q9, QA,
+ Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7, Q8, Q9, QA,
+ Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7, Q8, Q9, QA,
+ Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7, Q8, Q9, QA,
+ Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7, Q8, Q9, QA,
+ Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7, Q8, Q9, QA,
+ Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7, Q8, Q9, QA,
+ Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7, Q8, Q9, QA,
+ Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7, Q8, Q9, QA,
+ Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7, Q8, Q9, QA,
+ Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7, Q8, Q9, QA,
+ 0, 0, 0, 0, 0, 0, 0
+};
+
+#undef Q0
+#undef Q1
+#undef Q2
+#undef Q3
+#undef Q4
+#undef Q5
+#undef Q6
+#undef Q7
+#undef Q8
+#undef Q9
+#undef QA
+
+static const float q_5[15] =
+{
+ (-14 << 15)/15.0,(-12 << 15)/15.0,(-10 << 15)/15.0,
+ ( -8 << 15)/15.0,( -6 << 15)/15.0,( -4 << 15)/15.0,
+ ( -2 << 15)/15.0, 0.0 ,( 2 << 15)/15.0,
+ ( 4 << 15)/15.0,( 6 << 15)/15.0,( 8 << 15)/15.0,
+ ( 10 << 15)/15.0,( 12 << 15)/15.0,( 14 << 15)/15.0
+};
+
+//
+// Scale factors for convert_to_float
+//
+
+static const uint32_t u32_scale_factors[25] =
+{
+ 0x38000000, //2 ^ -(0 + 15)
+ 0x37800000, //2 ^ -(1 + 15)
+ 0x37000000, //2 ^ -(2 + 15)
+ 0x36800000, //2 ^ -(3 + 15)
+ 0x36000000, //2 ^ -(4 + 15)
+ 0x35800000, //2 ^ -(5 + 15)
+ 0x35000000, //2 ^ -(6 + 15)
+ 0x34800000, //2 ^ -(7 + 15)
+ 0x34000000, //2 ^ -(8 + 15)
+ 0x33800000, //2 ^ -(9 + 15)
+ 0x33000000, //2 ^ -(10 + 15)
+ 0x32800000, //2 ^ -(11 + 15)
+ 0x32000000, //2 ^ -(12 + 15)
+ 0x31800000, //2 ^ -(13 + 15)
+ 0x31000000, //2 ^ -(14 + 15)
+ 0x30800000, //2 ^ -(15 + 15)
+ 0x30000000, //2 ^ -(16 + 15)
+ 0x2f800000, //2 ^ -(17 + 15)
+ 0x2f000000, //2 ^ -(18 + 15)
+ 0x2e800000, //2 ^ -(19 + 15)
+ 0x2e000000, //2 ^ -(20 + 15)
+ 0x2d800000, //2 ^ -(21 + 15)
+ 0x2d000000, //2 ^ -(22 + 15)
+ 0x2c800000, //2 ^ -(23 + 15)
+ 0x2c000000 //2 ^ -(24 + 15)
+};
+
+static float *scale_factor = (float*)u32_scale_factors;
+
+//These store the persistent state of the packed mantissas
+static float q_1[2];
+static float q_2[2];
+static float q_4[1];
+static int32_t q_1_pointer;
+static int32_t q_2_pointer;
+static int32_t q_4_pointer;
+static float __inline__
+coeff_get_float(uint16_t bap, uint16_t dithflag, uint16_t exp);
+
+//Conversion from bap to number of bits in the mantissas
+//zeros account for cases 0,1,2,4 which are special cased
+static uint16_t qnttztab[16] =
+{
+ 0, 0, 0, 3,
+ 0, 4, 5, 6,
+ 7, 8, 9, 10,
+ 11, 12, 14, 16
+};
+
+static void coeff_reset(void);
+static float coeff_get_float(uint16_t bap, uint16_t dithflag, uint16_t exp);
+static void coeff_uncouple_ch(float samples[],bsi_t *bsi,audblk_t *audblk,uint32_t ch);
+
+void coeff_unpack(bsi_t *bsi, audblk_t *audblk, stream_samples_t samples)
+{
+ uint16_t i,j;
+ uint32_t done_cpl = 0;
+
+ coeff_reset();
+
+ for(i=0; i< bsi->nfchans; i++) {
+ for(j=0; j < audblk->endmant[i]; j++)
+ samples[i][j] = coeff_get_float(audblk->fbw_bap[i][j], audblk->dithflag[i], audblk->fbw_exp[i][j]);
+
+ if(audblk->cplinu && audblk->chincpl[i] && !(done_cpl)) {
+ // ncplmant is equal to 12 * ncplsubnd
+ // Don't dither coupling channel until channel
+ // separation so that interchannel noise is uncorrelated
+ for(j=audblk->cplstrtmant; j < audblk->cplendmant; j++)
+ audblk->cpl_flt[j] = coeff_get_float(audblk->cpl_bap[j],0, audblk->cpl_exp[j]);
+ done_cpl = 1;
+ }
+ }
+
+ //uncouple the channel if necessary
+ if(audblk->cplinu) {
+ for(i=0; i< bsi->nfchans; i++) {
+ if(audblk->chincpl[i])
+ coeff_uncouple_ch(samples[i],bsi,audblk,i);
+ }
+
+ }
+
+ if(bsi->lfeon) {
+ // There are always 7 mantissas for lfe, no dither for lfe
+ for(j=0; j < 7 ; j++)
+ samples[5][j] = coeff_get_float(audblk->lfe_bap[j], 0, audblk->lfe_exp[j]);
+ }
+}
+
+
+/**
+ * Fetch a float from the bitstream
+ **/
+
+static float inline coeff_get_float (uint16_t bap, uint16_t dithflag, uint16_t exp)
+{
+ uint16_t dummy = 0;
+
+ //If the bap is 0-5 then we have special cases to take care of
+ switch(bap) {
+ case 0:
+ if(dithflag)
+ return (dither_gen() * scale_factor[exp]);
+ return 0.0;
+
+ case 1:
+ if (q_1_pointer >= 0)
+ return(q_1[q_1_pointer--] * scale_factor[exp]);
+
+ if ((dummy = bitstream_get (5)) > 26)
+ goto error;
+
+ q_1[1] = q_1_1[dummy];
+ q_1[0] = q_1_2[dummy];
+ q_1_pointer = 1;
+
+ return (q_1_0[dummy] * scale_factor[exp]);
+
+ case 2:
+ if(q_2_pointer >= 0)
+ return (q_2[q_2_pointer--] * scale_factor[exp]);
+
+ if ((dummy = bitstream_get (7)) > 124)
+ goto error;
+
+ q_2[1] = q_2_1[dummy];
+ q_2[0] = q_2_2[dummy];
+ q_2_pointer = 1;
+
+ return (q_2_0[dummy] * scale_factor[exp]);
+
+ case 3:
+ if ((dummy = bitstream_get (3)) > 6)
+ goto error;
+
+ return (q_3[dummy] * scale_factor[exp]);
+
+ case 4:
+ if(q_4_pointer >= 0)
+ return (q_4[q_4_pointer--] * scale_factor[exp]);
+
+ if ((dummy = bitstream_get (7)) > 120)
+ goto error;
+
+ q_4[0] = q_4_1[dummy];
+ q_4_pointer = 0;
+
+ return (q_4_0[dummy] * scale_factor[exp]);
+
+ case 5:
+ if ((dummy = bitstream_get (4)) > 14)
+ goto error;
+
+ return (q_5[dummy] * scale_factor[exp]);
+
+ default:
+ dummy = bitstream_get(qnttztab[bap]);
+ dummy <<= 16 - qnttztab[bap];
+ return ((int16_t)dummy * scale_factor[exp]);
+ }
+
+error:
+#ifdef FAST_ERROR
+ HANDLE_ERROR ();
+#else
+ if(!error_flag)
+ fprintf(stderr,"** Invalid mantissa - skipping frame **\n");
+ error_flag = 1;
+
+ return 0.0;
+#endif
+}
+
+
+/**
+ * Reset the mantissa state
+ **/
+
+static void coeff_reset(void)
+{
+ q_1_pointer = q_2_pointer = q_4_pointer = -1;
+}
+
+
+/**
+ * Uncouple the coupling channel into a fbw channel
+ **/
+
+static void coeff_uncouple_ch (float samples[],bsi_t *bsi,audblk_t *audblk,uint32_t ch)
+{
+ uint32_t bnd = 0;
+ uint32_t sub_bnd = 0;
+ uint32_t i,j;
+ float cpl_coord = 1.0;
+ uint32_t cpl_exp_tmp;
+ uint32_t cpl_mant_tmp;
+
+ for (i=audblk->cplstrtmant;i<audblk->cplendmant;) {
+ if (!audblk->cplbndstrc[sub_bnd++]) {
+ cpl_exp_tmp = audblk->cplcoexp[ch][bnd] + 3 * audblk->mstrcplco[ch];
+ if (audblk->cplcoexp[ch][bnd] == 15)
+ cpl_mant_tmp = (audblk->cplcomant[ch][bnd]) << 11;
+ else
+ cpl_mant_tmp = ((0x10) | audblk->cplcomant[ch][bnd]) << 10;
+
+ cpl_coord = (cpl_mant_tmp * scale_factor[cpl_exp_tmp]) * 8.0f;
+
+ //Invert the phase for the right channel if necessary
+ if(bsi->acmod == 0x2 && audblk->phsflginu && ch == 1 && audblk->phsflg[bnd])
+ cpl_coord *= -1;
+
+ bnd++;
+ }
+
+ for(j=0;j < 12; j++) {
+ // Get new dither values for each channel if necessary,
+ // so the channels are uncorrelated
+ if(audblk->dithflag[ch] && !audblk->cpl_bap[i])
+ samples[i] = cpl_coord * (dither_gen() * scale_factor[audblk->cpl_exp[i]]);
+ else
+ samples[i] = cpl_coord * audblk->cpl_flt[i];
+
+ i++;
+ }
+ }
+}
generated by cgit v1.2.3 (git 2.25.1) at 2025-04-27 14:39:14 +0000