arm_graphic_equalizer_example_q31.c

/* ----------------------------------------------------------------------     
* Copyright (C) 2011 ARM Limited. All rights reserved. 
*     
* $Date:        15. December 2011   
* $Revision:    V2.0.0  
*     
* Project:      Cortex-R4 DSP Library 
* Title:          arm_graphic_equalizer_example_q31.c         
*  
* Description:  Example showing an audio graphic equalizer constructed
*              out of Biquad filters.
* 
* Target Processor:          Cortex-R4
*
* Version 2.0.0 2011/12/15
*     Final release. 
* 
* ---------------------------------------------------------------------------- */ 

#include "arm_math.h" 
#include "math_helper.h"

/* Length of the overall data in the test */ 
#define TESTLENGTH 320

/* Block size for the underlying processing */
#define BLOCKSIZE 32

/* Total number of blocks to run */
#define NUMBLOCKS (TESTLENGTH/BLOCKSIZE)

/* Number of 2nd order Biquad stages per filter */
#define NUMSTAGES 2

#define SNR_THRESHOLD_F32  98
 
/* ------------------------------------------------------------------- 
 * External Declarations for Input and Output buffers 
 * ------------------------------------------------------------------- */
 
extern float32_t testInput_f32[TESTLENGTH]; 
static float32_t testOutput[TESTLENGTH]; 

extern float32_t testRefOutput_f32[TESTLENGTH];

/* ----------------------------------------------------------------------  
** Q31 state buffers for Band1, Band2, Band3, Band4, Band5  
** ------------------------------------------------------------------- */  
   
static q63_t biquadStateBand1Q31[4 * 2];   
static q63_t biquadStateBand2Q31[4 * 2];   
static q31_t biquadStateBand3Q31[4 * 2];   
static q31_t biquadStateBand4Q31[4 * 2];   
static q31_t biquadStateBand5Q31[4 * 2];   
 
/* ----------------------------------------------------------------------  
** Q31 input and output buffers  
** ------------------------------------------------------------------- */  

q31_t inputQ31[BLOCKSIZE];   
q31_t outputQ31[BLOCKSIZE];  
 
/* ----------------------------------------------------------------------
** Entire coefficient table.  There are 10 coefficients per 4th order Biquad
** cascade filter.  The first 10 coefficients correspond to the -9 dB gain
** setting of band 1; the next 10 coefficient correspond to the -8 dB gain
** setting of band 1; and so on.  There are 10*19=190 coefficients in total
** for band 1 (gains = -9, -8, -7, ..., 9).  After this come the 190 coefficients
** for band 2.
**
** The coefficients are in Q29 format and require a postShift of 2.
** ------------------------------------------------------------------- */

const q31_t coeffTable[950] = {

    /* Band 1, -9 dB gain */
    535576962, -1071153923, 535576962, 1073741824, -536870912, 535576962, -1063501998, 527979313, 1060865294, -524146981, 
    /* Band 1, -8 dB gain */
    535723226, -1071446451, 535723226, 1073741824, -536870912, 535723226, -1063568947, 527903217, 1061230578, -524503778, 
    535868593, -1071737186, 535868593, 1073741824, -536870912, 535868593, -1063627467, 527819780, 1061585502, -524850686, 
    536013181, -1072026363, 536013181, 1073741824, -536870912, 536013181, -1063677598, 527728935, 1061930361, -525187972, 
    536157109, -1072314217, 536157109, 1073741824, -536870912, 536157109, -1063719372, 527630607, 1062265438, -525515897, 
    536300492, -1072600983, 536300492, 1073741824, -536870912, 536300492, -1063752815, 527524720, 1062591011, -525834716, 
    536443447, -1072886894, 536443447, 1073741824, -536870912, 536443447, -1063777945, 527411186, 1062907350, -526144676, 
    536586091, -1073172183, 536586091, 1073741824, -536870912, 536586091, -1063794775, 527289917, 1063214717, -526446017, 
    536728541, -1073457082, 536728541, 1073741824, -536870912, 536728541, -1063803308, 527160815, 1063513366, -526738975, 
    536870912, -1073741824, 536870912, 1073741824, -536870912, 536870912, -1063803543, 527023777, 1063803543, -527023777, 
    537013321, -1074026642, 537013321, 1073741824, -536870912, 537013321, -1063795470, 526878696, 1064085490, -527300648, 
    537155884, -1074311768, 537155884, 1073741824, -536870912, 537155884, -1063779073, 526725455, 1064359439, -527569803, 
    537298718, -1074597435, 537298718, 1073741824, -536870912, 537298718, -1063754328, 526563934, 1064625617, -527831454, 
    537441939, -1074883878, 537441939, 1073741824, -536870912, 537441939, -1063721205, 526394005, 1064884245, -528085806, 
    537585666, -1075171331, 537585666, 1073741824, -536870912, 537585666, -1063679666, 526215534, 1065135536, -528333059, 
    537730015, -1075460030, 537730015, 1073741824, -536870912, 537730015, -1063629666, 526028380, 1065379699, -528573409, 
    537875106, -1075750212, 537875106, 1073741824, -536870912, 537875106, -1063571152, 525832396, 1065616936, -528807045, 
    538021057, -1076042114, 538021057, 1073741824, -536870912, 538021057, -1063504065, 525627429, 1065847444, -529034151, 
    538167989, -1076335977, 538167989, 1073741824, -536870912, 538167989, -1063428338, 525413317, 1066071412, -529254907, 
    
    /* Band 2, -9 dB gain */
    531784976, -1055497692, 523873415, 1066213307, -529420241, 531784976, -1040357886, 509828014, 1028908252, -494627367,
    /* Band 2, -8 dB gain */ 
    532357636, -1056601982, 524400080, 1066115844, -529326645, 532357636, -1040623406, 509562600, 1030462237, -496062122, 
    532927392, -1057707729, 524931110, 1066024274, -529239070, 532927392, -1040848253, 509262081, 1031969246, -497457090, 
    533494678, -1058816094, 525467240, 1065939047, -529157961, 533494678, -1041032161, 508925950, 1033429976, -498812573, 
    534059929, -1059928204, 526009170, 1065860582, -529083734, 534059929, -1041174868, 508553717, 1034845124, -500128887, 
    534623580, -1061045148, 526557561, 1065789260, -529016764, 534623580, -1041276126, 508144920, 1036215393, -501406373, 
    535186068, -1062167969, 527113032, 1065725420, -528957385, 535186068, -1041335703, 507699125, 1037541500, -502645399, 
    535747827, -1063297666, 527676151, 1065669351, -528905879, 535747827, -1041353386, 507215934, 1038824183, -503846368, 
    536309295, -1064435183, 528247436, 1065621289, -528862476, 536309295, -1041328990, 506694984, 1040064203, -505009724, 
    536870912, -1065581413, 528827349, 1065581413, -528827349, 536870912, -1041262354, 506135953, 1041262354, -506135953, 
    537433117, -1066737194, 529416295, 1065549847, -528800610, 537433117, -1041153346, 505538564, 1042419457, -507225588, 
    537996352, -1067903307, 530014622, 1065526651, -528782316, 537996352, -1041001864, 504902578, 1043536370, -508279208, 
    538561061, -1069080480, 530622620, 1065511830, -528772462, 538561061, -1040807833, 504227800, 1044613981, -509297437, 
    539127690, -1070269387, 531240527, 1065505333, -528770987, 539127690, -1040571205, 503514074, 1045653211, -510280946, 
    539696690, -1071470656, 531868525, 1065507054, -528777778, 539696690, -1040291951, 502761277, 1046655011, -511230450, 
    540268512, -1072684867, 532506750, 1065516837, -528792672, 540268512, -1039970063, 501969320, 1047620358, -512146700, 
    540843613, -1073912567, 533155297, 1065534483, -528815459, 540843613, -1039605542, 501138139, 1048550251, -513030484, 
    541422451, -1075154268, 533814224, 1065559750, -528845892, 541422451, -1039198394, 500267687, 1049445708, -513882621, 
    542005489, -1076410460, 534483561, 1065592362, -528883686, 542005489, -1038748624, 499357932, 1050307760, -514703956, 
    518903861, -1001986830, 486725277, 1037235801, -502367695, 518903861, -945834422, 446371043, 902366163, -400700571, 
    520899989, -1005630916, 488289126, 1036926846, -502147311, 520899989, -946490935, 445581846, 907921945, -404936158, 
    522893209, -1009290002, 489869792, 1036650484, -501961419, 522893209, -947006359, 444685310, 913306106, -409075225, 
    524884763, -1012968199, 491470256, 1036407567, -501810737, 524884763, -947377809, 443679533, 918521018, -413116221, 
    526875910, -1016669649, 493093518, 1036198712, -501695739, 526875910, -947602324, 442562672, 923569247, -417057897, 
    528867927, -1020398503, 494742575, 1036024293, -501616651, 528867927, -947676875, 441332970, 928453558, -420899319, 
    530862111, -1024158905, 496420407, 1035884447, -501573457, 530862111, -947598385, 439988777, 933176909, -424639872, 
    532859778, -1027954970, 498129955, 1035779077, -501565907, 532859778, -947363742, 438528571, 937742446, -428279254, 
    534862260, -1031790763, 499874098, 1035707863, -501593525, 534862260, -946969823, 436950987, 942153486, -431817474, 
    536870912, -1035670279, 501655630, 1035670279, -501655630, 536870912, -946413508, 435254839, 946413508, -435254839, 
    538887107, -1039597419, 503477238, 1035665609, -501751354, 538887107, -945691703, 433439146, 950526127, -438591937, 
    540912240, -1043575967, 505341475, 1035692963, -501879659, 540912240, -944801359, 431503152, 954495080, -441829621, 
    542947726, -1047609569, 507250741, 1035751307, -502039364, 542947726, -943739490, 429446349, 958324201, -444968987, 
    544995000, -1051701717, 509207261, 1035839473, -502229165, 544995000, -942503190, 427268492, 962017400, -448011351, 
    547055523, -1055855728, 511213065, 1035956193, -502447657, 547055523, -941089647, 424969617, 965578640, -450958226, 
    549130774, -1060074734, 513269973, 1036100110, -502693359, 549130774, -939496155, 422550049, 969011913, -453811298, 
    551222259, -1064361672, 515379585, 1036269804, -502964731, 551222259, -937720119, 420010407, 972321228, -456572401, 
    553331507, -1068719280, 517543273, 1036463810, -503260192, 553331507, -935759057, 417351601, 975510582, -459243495, 
    555460072, -1073150100, 519762181, 1036680633, -503578144, 555460072, -933610600, 414574832, 978583948, -461826644, 
    494084017, -851422604, 404056273, 930151631, -423619864, 494084017, -673714108, 339502486, 561843007, -265801750, 
    498713542, -859177141, 406587077, 929211656, -423786402, 498713542, -673274906, 338185129, 573719128, -272222942, 
    503369016, -867012190, 409148384, 928362985, -424054784, 503369016, -672533059, 336693984, 585290277, -278599028, 
    508052536, -874935599, 411746438, 927604291, -424422151, 508052536, -671478538, 335026905, 596558312, -284920289, 
    512766286, -882955583, 414387826, 926933782, -424885216, 512766286, -670100998, 333182045, 607525792, -291177811, 
    517512534, -891080712, 417079474, 926349262, -425440318, 517512534, -668389789, 331157902, 618195914, -297363485, 
    522293635, -899319903, 419828635, 925848177, -426083491, 522293635, -666333963, 328953368, 628572440, -303470012, 
    527112032, -907682405, 422642886, 925427679, -426810526, 527112032, -663922286, 326567785, 638659631, -309490882, 
    531970251, -916177781, 425530105, 925084675, -427617023, 531970251, -661143261, 324000998, 648462180, -315420352, 
    536870912, -924815881, 428498454, 924815881, -428498454, 536870912, -657985147, 321253420, 657985147, -321253420, 
    541816719, -933606817, 431556352, 924617870, -429450209, 541816719, -654435997, 318326093, 667233900, -326985786, 
    546810467, -942560921, 434712438, 924487114, -430467639, 546810467, -650483688, 315220754, 676214053, -332613816, 
    551855042, -951688708, 437975532, 924420027, -431546101, 551855042, -646115970, 311939896, 684931422, -338134495, 
    556953421, -961000826, 441354588, 924413001, -432680993, 556953421, -641320513, 308486839, 693391970, -343545389, 
    562108672, -970508005, 444858642, 924462435, -433867780, 562108672, -636084967, 304865786, 701601770, -348844597, 
    567323959, -980220994, 448496743, 924564764, -435102022, 567323959, -630397020, 301081886, 709566963, -354030710, 
    572602539, -990150500, 452277894, 924716482, -436379394, 572602539, -624244471, 297141281, 717293726, -359102767, 
    577947763, -1000307125, 456210977, 924914158, -437695705, 577947763, -617615296, 293051155, 724788245, -364060214, 
    583363084, -1010701292, 460304674, 925154455, -439046908, 583363084, -610497723, 288819761, 732056685, -368902865, 
    387379495, -506912469, 196933274, 840112184, -347208270, 387379495, 506912469, 196933274, -840112184, -347208270, 
    401658082, -532275898, 207149427, 833765363, -343175316, 401658082, 532275898, 207149427, -833765363, -343175316, 
    416472483, -558722695, 217902617, 827270154, -339107319, 416472483, 558722695, 217902617, -827270154, -339107319, 
    431841949, -586290861, 229212798, 820624988, -335007540, 431841949, 586290861, 229212798, -820624988, -335007540, 
    447786335, -615019650, 241100489, 813828443, -330879528, 447786335, 615019650, 241100489, -813828443, -330879528, 
    464326111, -644949597, 253586805, 806879270, -326727141, 464326111, 644949597, 253586805, -806879270, -326727141, 
    481482377, -676122557, 266693475, 799776409, -322554559, 481482377, 676122557, 266693475, -799776409, -322554559, 
    499276882, -708581728, 280442865, 792519013, -318366296, 499276882, 708581728, 280442865, -792519013, -318366296, 
    517732032, -742371685, 294857996, 785106465, -314167221, 517732032, 742371685, 294857996, -785106465, -314167221, 
    536870912, -777538408, 309962566, 777538408, -309962566, 536870912, 777538408, 309962566, -777538408, -309962566, 
    556717294, -814129313, 325780968, 769814766, -305757943, 556717294, 814129313, 325780968, -769814766, -305757943, 
    577295658, -852193284, 342338310, 761935777, -301559360, 577295658, 852193284, 342338310, -761935777, -301559360, 
    598631206, -891780698, 359660433, 753902014, -297373230, 598631206, 891780698, 359660433, -753902014, -297373230, 
    620749877, -932943463, 377773927, 745714425, -293206383, 620749877, 932943463, 377773927, -745714425, -293206383, 
    643678365, -975735041, 396706151, 737374355, -289066077, 643678365, 975735041, 396706151, -737374355, -289066077, 
    667444134, -1020210487, 416485252, 728883588, -284960004, 667444134, 1020210487, 416485252, -728883588, -284960004, 
    692075438, -1066426476, 437140179, 720244375, -280896294, 692075438, 1066426476, 437140179, -720244375, -280896294, 
    717601336, -1114441339, 458700704, 711459472, -276883515, 717601336, 1114441339, 458700704, -711459472, -276883515, 
    744051710, -1164315096, 481197437, 702532174, -272930673, 744051710, 1164315096, 481197437, -702532174, -272930673 

};

/* ----------------------------------------------------------------------
** Desired gains, in dB, per band
** ------------------------------------------------------------------- */

int gainDB[5] = {0, -3, 6, 4, -6};

float32_t snr;


/* ---------------------------------------------------------------------- 
 * Graphic equalizer Example 
 * ------------------------------------------------------------------- */ 
 
int32_t main(void) 
{ 
  float32_t  *inputF32, *outputF32;  
  arm_biquad_cas_df1_32x64_ins_q31 S1; 
  arm_biquad_cas_df1_32x64_ins_q31 S2; 
  arm_biquad_casd_df1_inst_q31 S3; 
  arm_biquad_casd_df1_inst_q31 S4; 
  arm_biquad_casd_df1_inst_q31 S5; 
  int i;
  int32_t status;
     
  inputF32 = &testInput_f32[0];  
  outputF32 = &testOutput[0]; 
     
  /* Initialize the state and coefficient buffers for all Biquad sections */

  arm_biquad_cas_df1_32x64_init_q31(&S1, NUMSTAGES, 
                    (q31_t *) &coeffTable[190*0 + 10*(gainDB[0] + 9)],
                    &biquadStateBand1Q31[0], 2);

  arm_biquad_cas_df1_32x64_init_q31(&S2, NUMSTAGES, 
                    (q31_t *) &coeffTable[190*1 + 10*(gainDB[1] + 9)],
                    &biquadStateBand2Q31[0], 2);
     
  arm_biquad_cascade_df1_init_q31(&S3, NUMSTAGES, 
                  (q31_t *) &coeffTable[190*2 + 10*(gainDB[2] + 9)],
                  &biquadStateBand3Q31[0], 2);

  arm_biquad_cascade_df1_init_q31(&S4, NUMSTAGES, 
                  (q31_t *) &coeffTable[190*3 + 10*(gainDB[3] + 9)],
                  &biquadStateBand4Q31[0], 2); 
     
  arm_biquad_cascade_df1_init_q31(&S5, NUMSTAGES, 
                  (q31_t *) &coeffTable[190*4 + 10*(gainDB[4] + 9)],
                  &biquadStateBand5Q31[0], 2); 
     
 
  /* Call the process functions and needs to change filter coefficients  
     for varying the gain of each band */ 
 
  for(i=0; i < NUMBLOCKS; i++) 
    {    

      /* ---------------------------------------------------------------------- 
      ** Convert block of input data from float to Q31 
      ** ------------------------------------------------------------------- */ 

      arm_float_to_q31(inputF32 + (i*BLOCKSIZE), inputQ31, BLOCKSIZE);     
         
      /* ----------------------------------------------------------------------
      ** Scale down by 1/8.  This provides additional headroom so that the
      ** graphic EQ can apply gain.
      ** ------------------------------------------------------------------- */

      arm_scale_q31(inputQ31, 0x7FFFFFFF, -3, inputQ31, BLOCKSIZE);

      /* ----------------------------------------------------------------------
      ** Call the Q31 Biquad Cascade DF1 32x64 process function for band1, band2
      ** ------------------------------------------------------------------- */

      arm_biquad_cas_df1_32x64_q31(&S1, inputQ31, outputQ31, BLOCKSIZE); 
      arm_biquad_cas_df1_32x64_q31(&S2, outputQ31, outputQ31, BLOCKSIZE); 

      /* ---------------------------------------------------------------------- 
      ** Call the Q31 Biquad Cascade DF1 process function for band3, band4, band5
      ** ------------------------------------------------------------------- */        

      arm_biquad_cascade_df1_q31(&S3, outputQ31, outputQ31, BLOCKSIZE); 
      arm_biquad_cascade_df1_q31(&S4, outputQ31, outputQ31, BLOCKSIZE);  
      arm_biquad_cascade_df1_q31(&S5, outputQ31, outputQ31, BLOCKSIZE); 
 
      /* ---------------------------------------------------------------------- 
      ** Convert Q31 result back to float 
      ** ------------------------------------------------------------------- */ 

      arm_q31_to_float(outputQ31, outputF32 + (i * BLOCKSIZE), BLOCKSIZE);

      /* ---------------------------------------------------------------------- 
      ** Scale back up
      ** ------------------------------------------------------------------- */ 

      arm_scale_f32(outputF32 + (i * BLOCKSIZE), 8.0f, outputF32 + (i * BLOCKSIZE), BLOCKSIZE);
    }; 

    snr = arm_snr_f32(testRefOutput_f32, testOutput, TESTLENGTH);

    if (snr < SNR_THRESHOLD_F32) 
    { 
        status = ARM_MATH_TEST_FAILURE; 
    } 
    else
    {
        status = ARM_MATH_SUCCESS; 
    }
         
  /* ---------------------------------------------------------------------- 
  ** Loop here if the signal does not match the reference output.
  ** ------------------------------------------------------------------- */ 
     
  if( status != ARM_MATH_SUCCESS) 
    { 
      while(1); 
    } 


}