/*   File: subband_layer_2.cc*/#include <stdio.h>#include <stdlib.h>#include <fstream.h>#ifdef IRIX#include <dmedia/audio.h>#endif#ifdef SOLARIS#include <sys/audioio.h>#endif#include "athread.hh"#include "error.hh"#include "debug.hh"#include "util.hh"#include "sync.hh"#include "mpeg2const.hh"#include "mpeg2buff.hh"#include "astream.hh"#include "crc.hh"#include "header.hh"#include "obuffer.hh"#include "synthesis_filter.hh"#include "subband.hh"#include "subband_layer_1.hh"#include "subband_layer_2.hh"#include "scalefactors.hh"// data taken from ISO/IEC DIS 11172, Annexes 3-B.2[abcd] and 3-B.4:// subbands 0-2 in tables 3-B.2a and 2b: (index is allocation)static const uint32 table_ab1_codelength[16] =  // bits per codeword{ 0, 5, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 };static const uint32 table_ab1_quantizationsteps[16] =  // number of steps if grouped, 0 if ungrouped{ 0, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };static const real table_ab1_factor[16] =  // factor for requantization: (real)sample * factor - 1.0 gives requantized sample{ 0.0, 1.0/2.0, 1.0/4.0, 1.0/8.0, 1.0/16.0, 1.0/32.0, 1.0/64.0,  1.0/128.0, 1.0/256.0, 1.0/512.0, 1.0/1024.0, 1.0/2048.0,  1.0/4096.0, 1.0/8192.0, 1.0/16384.0, 1.0/32768.0 };static const real table_ab1_c[16] =  // factor c for requantization from table 3-B.4{ 0.0,           1.33333333333, 1.14285714286, 1.06666666666, 1.03225806452,  1.01587301587, 1.00787401575, 1.00392156863, 1.00195694716, 1.00097751711,  1.00048851979, 1.00024420024, 1.00012208522, 1.00006103888, 1.00003051851,  1.00001525902 };static const real table_ab1_d[16] =  // addend d for requantization from table 3-B.4{ 0.0,           0.50000000000, 0.25000000000, 0.12500000000, 0.06250000000,  0.03125000000, 0.01562500000, 0.00781250000, 0.00390625000, 0.00195312500,  0.00097656250, 0.00048828125, 0.00024414063, 0.00012207031, 0.00006103516,  0.00003051758 };// subbands 3-... tables 3-B.2a and 2b:static const uint32 table_ab234_quantizationsteps[16] ={ 0, 3, 5, 0, 9, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };// subbands 3-10 in tables 3-B.2a and 2b:static const uint32 table_ab2_codelength[16] ={ 0, 5, 7, 3, 10, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 16 };static const real table_ab2_factor[16] ={ 0.0, 1.0/2.0, 1.0/4.0, 1.0/4.0, 1.0/8.0, 1.0/8.0, 1.0/16.0,  1.0/32.0, 1.0/64.0, 1.0/128.0, 1.0/256.0, 1.0/512.0,  1.0/1024.0, 1.0/2048.0, 1.0/4096.0, 1.0/32768.0 };static const real table_ab2_c[16] ={ 0.0,           1.33333333333, 1.60000000000, 1.14285714286, 1.77777777777,  1.06666666666, 1.03225806452, 1.01587301587, 1.00787401575, 1.00392156863,  1.00195694716, 1.00097751711, 1.00048851979, 1.00024420024, 1.00012208522,  1.00001525902 };static const real table_ab2_d[16] ={ 0.0,           0.50000000000, 0.50000000000, 0.25000000000, 0.50000000000,  0.12500000000, 0.06250000000, 0.03125000000, 0.01562500000, 0.00781250000,  0.00390625000, 0.00195312500, 0.00097656250, 0.00048828125, 0.00024414063,  0.00003051758 };// subbands 11-22 in tables 3-B.2a and 2b:static const uint32 table_ab3_codelength[8] = { 0, 5, 7, 3, 10, 4, 5, 16 };static const real table_ab3_factor[8] ={ 0.0, 1.0/2.0, 1.0/4.0, 1.0/4.0, 1.0/8.0, 1.0/8.0, 1.0/16.0, 1.0/32768.0 };static const real table_ab3_c[8] ={ 0.0,           1.33333333333, 1.60000000000, 1.14285714286, 1.77777777777,  1.06666666666, 1.03225806452, 1.00001525902 };static const real table_ab3_d[8] ={ 0.0,           0.50000000000, 0.50000000000, 0.25000000000, 0.50000000000,  0.12500000000, 0.06250000000, 0.00003051758 };// subbands 23-... in tables 3-B.2a and 2b:static const uint32 table_ab4_codelength[4] = { 0, 5, 7, 16 };static const real table_ab4_factor[8] = { 0.0, 1.0/2.0, 1.0/4.0, 1.0/32768.0 };static const real table_ab4_c[4] = { 0.0, 1.33333333333, 1.60000000000, 1.00001525902 };static const real table_ab4_d[4] = { 0.0, 0.50000000000, 0.50000000000, 0.00003051758 };// subbands in tables 3-B.2c and 2d:static const uint32 table_cd_codelength[16] ={ 0, 5, 7, 10, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 };static const uint32 table_cd_quantizationsteps[16] ={ 0, 3, 5, 9, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };static const real table_cd_factor[16] ={ 0.0, 1.0/2.0, 1.0/4.0, 1.0/8.0, 1.0/8.0, 1.0/16.0, 1.0/32.0, 1.0/64.0,  1.0/128.0, 1.0/256.0, 1.0/512.0, 1.0/1024.0, 1.0/2048.0, 1.0/4096.0,  1.0/8192.0, 1.0/16384.0 };static const real table_cd_c[16] ={ 0.0,           1.33333333333, 1.60000000000, 1.77777777777, 1.06666666666,  1.03225806452, 1.01587301587, 1.00787401575, 1.00392156863, 1.00195694716,  1.00097751711, 1.00048851979, 1.00024420024, 1.00012208522, 1.00006103888,  1.00003051851 };static const real table_cd_d[16] ={ 0.0,           0.50000000000, 0.50000000000, 0.50000000000, 0.12500000000,  0.06250000000, 0.03125000000, 0.01562500000, 0.00781250000, 0.00390625000,  0.00195312500, 0.00097656250, 0.00048828125, 0.00024414063, 0.00012207031,  0.00006103516 };/**********************/	// used for single channel mode/*** Standard Class ***/	// and in derived class for intensity/**********************/	// stereo modeSubbandLayer2::SubbandLayer2(uint32 subbandnumber){  this->subbandnumber=subbandnumber;  groupnumber=samplenumber=0;}uint32 SubbandLayer2::get_allocationlength (Header *header){  uint32 channel_bitrate = header->bitrate_index ();  // calculate bitrate per channel:  if (header->mode () != single_channel)    if (channel_bitrate == 4)      channel_bitrate = 1;    else      channel_bitrate -= 4;  if (channel_bitrate == 1 || channel_bitrate == 2)    // table 3-B.2c or 3-B.2d    if (subbandnumber <= 1)      return 4;    else      return 3;  else    // tables 3-B.2a or 3-B.2b    if (subbandnumber <= 10)      return 4;    else if (subbandnumber <= 22)      return 3;    else      return 2;}uint32 SubbandLayer2::prepare_sample_reading(Header *header, uint32 allocation, bool *grouping,	 uint32 *quantizationsteps, real *factor, uint32 *codelength, real *c, real *d){  uint32 channel_bitrate = header->bitrate_index ();  // calculate bitrate per channel:  if (header->mode () != single_channel)    if (channel_bitrate == 4)  channel_bitrate = 1;    else                       channel_bitrate -= 4;  *grouping = False;  if (channel_bitrate == 1 || channel_bitrate == 2){    // table 3-B.2c or 3-B.2d    if ((*quantizationsteps=table_cd_quantizationsteps[allocation])!=0)      *grouping=True;    *factor=table_cd_factor[allocation];    *codelength=table_cd_codelength[allocation];    *c=table_cd_c[allocation];    *d=table_cd_d[allocation];  }  else {    // tables 3-B.2a or 3-B.2b    if (subbandnumber <= 2){      if ((*quantizationsteps=table_ab1_quantizationsteps[allocation])!=0)        *grouping = True;      *factor = table_ab1_factor[allocation];      *codelength = table_ab1_codelength[allocation];      *c = table_ab1_c[allocation];      *d = table_ab1_d[allocation];    }    else {      if ((*quantizationsteps=table_ab234_quantizationsteps[allocation])!=0)        *grouping = True;      if (subbandnumber <= 10){        *factor = table_ab2_factor[allocation];        *codelength = table_ab2_codelength[allocation];        *c = table_ab2_c[allocation];        *d = table_ab2_d[allocation];      }      else if (subbandnumber <= 22){        *factor = table_ab3_factor[allocation];        *codelength = table_ab3_codelength[allocation];        *c = table_ab3_c[allocation];        *d = table_ab3_d[allocation];      }      else {        *factor = table_ab4_factor[allocation];        *codelength = table_ab4_codelength[allocation];        *c = table_ab4_c[allocation];        *d = table_ab4_d[allocation];      }    }  }    return channel_bitrate;}void SubbandLayer2::read_allocation(AudioStream *stream, Header *header, Crc16 *crc){  register uint32 length = get_allocationlength (header);  allocation = stream->get_bits (length);  if (crc)    crc->add_bits (allocation, length);}void SubbandLayer2::read_scalefactor_selection(AudioStream *stream, Crc16 *crc){  if (allocation){    scfsi = stream->get_bits (2);    if (crc) crc->add_bits (scfsi, 2);  }}void SubbandLayer2::read_scalefactor(AudioStream *stream, Header *header){  if (allocation){    switch (scfsi){      case 0:	scalefactor1 = stream->get_bits (6);	scalefactor2 = stream->get_bits (6);	scalefactor3 = stream->get_bits (6);	break;      case 1:	scalefactor1 = scalefactor2 = stream->get_bits (6);	scalefactor3 = stream->get_bits (6);	break;      case 2:	scalefactor1 = scalefactor2 = scalefactor3 = stream->get_bits (6);	break;      case 3:	scalefactor1 = stream->get_bits (6);	scalefactor2 = scalefactor3 = stream->get_bits (6);	break;    }    if (scalefactor1 == 63 || scalefactor2 == 63 || scalefactor3 == 63)      cerr << "WARNING: stream contains an illegal scalefactor!\n";	// MPEG-stream is corrupted!    prepare_sample_reading (header, allocation, &grouping, &quantizationsteps,			    &factor, &codelength, &c, &d);  }}bool SubbandLayer2::read_sampledata(AudioStream *stream){  if (allocation)    if (grouping){      uint32 samplecode = stream->get_bits (codelength);#ifdef DEBUG      if (samplecode == (1 << codelength) - 1)        cerr << "WARNING: stream contains an illegal subband sample!\n";  // MPEG-stream is corrupted!#endif      samples[0] = real (samplecode % quantizationsteps) * factor - 1.0;      samplecode /= quantizationsteps;      samples[1] = real (samplecode % quantizationsteps) * factor - 1.0;      samplecode /= quantizationsteps;      samples[2] = real (samplecode % quantizationsteps) * factor - 1.0;    }    else {      samples[0] = real (stream->get_bits (codelength)) * factor - 1.0;#ifdef DEBUG      if (samples[0] == (1 << codelength) - 1)        cerr << "WARNING: stream contains an illegal subband sample!\n";  // MPEG-stream is corrupted!#endif      samples[1] = real (stream->get_bits (codelength)) * factor - 1.0;#ifdef DEBUG      if (samples[1] == (1 << codelength) - 1)        cerr << "WARNING: stream contains an illegal subband sample!\n";  // MPEG-stream is corrupted!#endif      samples[2] = real (stream->get_bits (codelength)) * factor - 1.0;#ifdef DEBUG      if (samples[2] == (1 << codelength) - 1)        cerr << "WARNING: stream contains an illegal subband sample!\n";  // MPEG-stream is corrupted!#endif    }  samplenumber = 0;  return (++groupnumber == 12) ? True : False;}bool SubbandLayer2::put_next_sample(e_channels channels,				     SynthesisFilter *filter1, SynthesisFilter*){