remove code that was moved to seperate function fir_to_cldfb_fir

fclose(fid);

rmpath(fullfile(thispath,'..','param_bin'));

function F = fir_to_cldfb_fir( target_fir, num_cldfb_taps, eval_flag, legacy_flag )

[pFilter, D, S, L] = get_cldfb_filter;

cldfb_delay = D - S + 1; % processing delay given stride

pFilt = sqrt(S)/L * pFilter(:);

N = length(pFilt);

%legacy_flag = 1; % = 1 used to indicate slightly too short buffers as used to generate tested coefficients 

% Filter Bank analysis / synthesis filters

cldfb_mod_mat = exp(1i*((0:N-1)'-D/2) * ((0:L-1)+0.5) * pi/L ); % N x L modulation matrix with alternating sign periodicity of 2*L in time (row) direction

cldfb_ansyn_filters = pFilt .* cldfb_mod_mat; % all (L) analysis/synthesis filters

target_fir = target_fir(:);

fir_length = length(target_fir);

%% brute force least squares

if legacy_flag

   num_slots = ceil(fir_length/S) + 10; % used to generate tested IVAS coefficients in CLDFB HRIR ROM with slightly too short buffers 

   inp_len = S * num_slots;

   len = inp_len - cldfb_delay;

   idx_opt = cldfb_delay + (1:len);

   pos_offset = 200;

else

   num_slots = ceil((fir_length + 2 * N - 1) / S); % convolution with target fir, analysis + synthesis filters (of length N each)

   len = S * num_slots;

   inp_len = len;

   idx_opt = (1:len); % use all output samples in the optimization, including the filter bank delay

   pos_offset = 0;

end

% Big trial and error

Nbins = num_cldfb_taps * L;

Vreal = zeros(S*len, Nbins);  % all real for all shifts concatenated for each mask bin,

Vimag = zeros(S*len, Nbins);  % then all imag

r = zeros(S*len,1); % right hand side all shifts concatenated

x  = zeros(inp_len,1);

for pos = 1:S

   % input dirac pulse

   x(:) = 0;

   % target impulse response y0 for input pulse at pos

   out = x;

   out(pos+pos_offset+(0:fir_length-1)) = target_fir;

   y0 = [zeros(cldfb_delay,1);out(1:end-cldfb_delay)];

   r(len*(pos-1)+(1:len)) = y0(idx_opt);

   fprintf('.');

   % CLDFB analysis for impulse input

   x(pos+pos_offset) = 1;

   X = zeros(L,num_slots);

   frm_idx = (1:N)';

   x_tmp = [zeros(N-S,1);x];

   for slt = 1:num_slots

      X(:,slt) = sum(cldfb_ansyn_filters.*flipud(x_tmp(frm_idx))).';

      frm_idx = frm_idx + S;

   end

   for cldfb_bin = 1:Nbins

      cldfb_band = rem(cldfb_bin-1,L)+1;

      cldfb_lag = fix((cldfb_bin-1)/L);

      % real-valued filter contribution of a single tap

      frm_idx = cldfb_lag * S + (1:N)';

      y_tmp = zeros( num_slots * S + N - S,1);

      for slt = cldfb_lag+1:num_slots

         y_tmp(frm_idx) = y_tmp(frm_idx) + real(X(cldfb_band,slt-cldfb_lag) * cldfb_ansyn_filters(:,cldfb_band));

         frm_idx = frm_idx + S;

      end

      Vreal(len*(pos-1)+1:len*pos,cldfb_bin) = y_tmp(idx_opt);

      % imaginary-valued filter contribution of a single tap

      frm_idx = cldfb_lag * S + (1:N)';

      y_tmp(:) = 0;

      for slt = cldfb_lag+1:num_slots

         y_tmp(frm_idx) = y_tmp(frm_idx) + real(1i*X(cldfb_band,slt-cldfb_lag) * cldfb_ansyn_filters(:,cldfb_band));

         frm_idx = frm_idx + S;

      end

      Vimag(len*(pos-1)+1:len*pos,cldfb_bin) = y_tmp(idx_opt);

   end % bin

end % pos

fprintf('\n');

% solve lsq

V = [Vreal,Vimag];

M = V'*V;

Mrel = M + 1e-8*norm(M)*eye(size(M));

c = Mrel\(V'*r);

% map back to mask locations

F = zeros(L,num_cldfb_taps);

for cldfb_bin = 1:Nbins

   F(cldfb_bin) = c(cldfb_bin)+1i*c(Nbins+cldfb_bin);

end

if eval_flag

   % evaluation (not needed for table generation, needs signal processing toolbox)

   get_snr( target_fir, F, cldfb_ansyn_filters, cldfb_delay, S );

end

function get_snr( target_fir, cldfb_firs, cldfb_ansyn_filters, cldfb_delay, S )

rng(0);

num_samples = 5*48000;

x = randn(num_samples,1);

% Filter noise in time domain

y1 = fftfilt(target_fir,x);

% Filter noise in CLDFB domain

[N,L] = size(cldfb_ansyn_filters);

num_slots = ceil((num_samples + cldfb_delay) / S);

% analysis

X = zeros(L,num_slots);

frm_idx = (1:N)';

x_tmp = [zeros(N-S,1);x;zeros(cldfb_delay,1)];

for slt = 1:num_slots

   X(:,slt) = sum(cldfb_ansyn_filters.*flipud(x_tmp(frm_idx))).';

   frm_idx = frm_idx + S;

end

% filter

X = fftfilt(cldfb_firs.',X.').';

% synthesis

frm_idx =  (1:N)';

y_tmp = zeros( num_slots * S + N - S,1);

for slt = 1:num_slots

   y_tmp(frm_idx) = y_tmp(frm_idx) + real(sum(X(:,slt).' .* cldfb_ansyn_filters,2));

   frm_idx = frm_idx + S;

end

y2 = y_tmp(cldfb_delay+(1:num_samples));

plot(y1), hold on, plot(y2,'r--'), plot(y1-y2,'k'), hold off

set(gca,'xlim',[1,num_samples])

fprintf('SNR: %.1f dB \n', 10*log10(sum(y1.^2)/sum((y1-y2).^2)));

legend('time domain','CLDFB domain','difference')

title('Filtered noise')

function [h, D, S, L] = get_cldfb_filter()

% const float LDQMF_60[] in \lib_com\rom_com.c, line 5219 

S = 60; % stride

L = 60; % frequency bands

D = 240 + S - 1; % system delay

h = [

   0.0000953076,  0.0001230230,  0.0001279964,  0.0001260533,  0.0001211219 

   0.0001122123,  0.0001010860,  0.0000876540,  0.0000719883,  0.0000545472 

   0.0000352143,  0.0000145686, -0.0000074264, -0.0000303788, -0.0000539205 

  -0.0000782743, -0.0001028838, -0.0001275374, -0.0001520015, -0.0001760167 

  -0.0001997108, -0.0002226708, -0.0002446725, -0.0002655797, -0.0002852145 

  -0.0003034996, -0.0003203036, -0.0003356283, -0.0003493345, -0.0003614030 

  -0.0003719004, -0.0003807641, -0.0003881051, -0.0003939842, -0.0003985357 

  -0.0004019095, -0.0004041938, -0.0004056677, -0.0004065430, -0.0004069925 

  -0.0004072535, -0.0004075877, -0.0004083676, -0.0004098394, -0.0004122990 

  -0.0004160839, -0.0004214063, -0.0004285777, -0.0004378651, -0.0004495422 

  -0.0004637682, -0.0004806494, -0.0005003878, -0.0005231378, -0.0005489803 

  -0.0005777747, -0.0006095612, -0.0006443121, -0.0006813223, -0.0007226231 

  -0.0007722576, -0.0008268412, -0.0008839625, -0.0009417336, -0.0010004630 

  -0.0010601623, -0.0011206097, -0.0011817788, -0.0012432419, -0.0013045983 

  -0.0013656860, -0.0014260965, -0.0014855355, -0.0015435946, -0.0015999591 

  -0.0016543545, -0.0017062968, -0.0017554691, -0.0018015467, -0.0018441341 

  -0.0018829798, -0.0019177221, -0.0019480695, -0.0019736972, -0.0019943134 

  -0.0020097434, -0.0020197174, -0.0020240925, -0.0020226294, -0.0020152442 

  -0.0020017736, -0.0019820682, -0.0019561697, -0.0019240153, -0.0018855907 

  -0.0018409232, -0.0017900462, -0.0017330211, -0.0016699535, -0.0016009507 

  -0.0015261442, -0.0014456788, -0.0013597424, -0.0012685407, -0.0011722331 

  -0.0010710671, -0.0009652392, -0.0008549765, -0.0007405236, -0.0006221444 

  -0.0005001140, -0.0003745670, -0.0002458634, -0.0001142541,  0.0000199491 

   0.0001564174,  0.0002949402,  0.0004350246,  0.0005769439,  0.0007203126 

  -0.0008803223, -0.0010328424, -0.0011841310, -0.0013346316, -0.0014848098 

  -0.0016343417, -0.0017832819, -0.0019316213, -0.0020790498, -0.0022252349 

  -0.0023701149, -0.0025136294, -0.0026556554, -0.0027960713, -0.0029348312 

  -0.0030717771, -0.0032068293, -0.0033399195, -0.0034709862, -0.0035999804 

  -0.0037267797, -0.0038513308, -0.0039736414, -0.0040935921, -0.0042111278 

  -0.0043262239, -0.0044388464, -0.0045489701, -0.0046565188, -0.0047614835 

  -0.0048637423, -0.0049632201, -0.0050599808, -0.0051539382, -0.0052450863 

  -0.0053333500, -0.0054187514, -0.0055012843, -0.0055808770, -0.0056575472 

  -0.0057313135, -0.0058021732, -0.0058701355, -0.0059352517, -0.0059975707 

  -0.0060571772, -0.0061141332, -0.0061685541, -0.0062205540, -0.0062703062 

  -0.0063179093, -0.0063635921, -0.0064075105, -0.0064498796, -0.0064908965 

  -0.0065308069, -0.0065698619, -0.0066083665, -0.0066466411, -0.0066849431 

  -0.0067233290, -0.0067621553, -0.0068021296, -0.0068436749, -0.0068870094 

  -0.0069324085, -0.0069801519, -0.0070305937, -0.0070840055, -0.0071406048 

  -0.0072006541, -0.0072644479, -0.0073321410, -0.0074039386, -0.0074799177 

  -0.0075602704, -0.0076450342, -0.0077342330, -0.0078278277, -0.0079257628 

  -0.0080279401, -0.0081341872, -0.0082442267, -0.0083577875, -0.0084744738 

  -0.0085938899, -0.0087156557, -0.0088391500, -0.0089637861, -0.0090888245 

  -0.0092134504, -0.0093367994, -0.0094579896, -0.0095760096, -0.0096898535 

  -0.0097982995, -0.0099003557, -0.0099947909, -0.0100801717, -0.0101551116 

  -0.0102182031, -0.0102678994, -0.0103026126, -0.0103207529, -0.0103206923 

  -0.0103006857, -0.0102590285, -0.0101939747, -0.0101036867, -0.0099863587 

  -0.0098401112, -0.0096632261, -0.0094537362, -0.0092098210, -0.0089295702 

  -0.0086111929, -0.0082527259, -0.0078523541, -0.0074084769, -0.0069190590 

   0.0063841688,  0.0057985946,  0.0051621343,  0.0044734711,  0.0037309236 

   0.0029329660,  0.0020781513,  0.0011651339,  0.0001925042, -0.0008409545 

  -0.0019364181, -0.0030950012, -0.0043176264, -0.0056051607, -0.0069584334 

  -0.0083780792, -0.0098646237, -0.0114185056, -0.0130400723, -0.0147295250 

  -0.0164868534, -0.0183120724, -0.0202049762, -0.0221651513, -0.0241921283 

  -0.0262852497, -0.0284437388, -0.0306666382, -0.0329528190, -0.0353010744 

  -0.0377098918, -0.0401776619, -0.0427025780, -0.0452826768, -0.0479161367 

  -0.0506004691, -0.0533332452, -0.0561118126, -0.0589331910, -0.0617944039 

  -0.0646922663, -0.0676232576, -0.0705836788, -0.0735698044, -0.0765774846 

  -0.0796026587, -0.0826408863, -0.0856874809, -0.0887378305, -0.0917868018 

  -0.0948293805, -0.0978601947, -0.1008738130, -0.1038645208, -0.1068264544 

  -0.1097536832, -0.1126400903, -0.1154794544, -0.1182654947, -0.1209914312 

  -0.1236500666, -0.1262341589, -0.1287376434, -0.1311538219, -0.1334753036 

  -0.1356947273, -0.1378047168, -0.1397978216, -0.1416664869, -0.1434033662 

  -0.1450008005, -0.1464512348, -0.1477471888, -0.1488809884, -0.1498452872 

  -0.1506324410, -0.1512351334, -0.1516460329, -0.1518578976, -0.1518635303 

  -0.1516559124, -0.1512281001, -0.1505732536, -0.1496847868, -0.1485562176 

  -0.1471813470, -0.1455538720, -0.1436681300, -0.1415183097, -0.1390990764 

  -0.1364052594, -0.1334318966, -0.1301742792, -0.1266280264, -0.1227891371 

  -0.1186537445, -0.1142183766, -0.1094799563, -0.1044355705, -0.0990828425 

  -0.0934195668, -0.0874440819, -0.0811550021, -0.0745511875, -0.0676321834 

  -0.0603975877, -0.0528475679, -0.0449828543, -0.0368040986, -0.0283128861 

  -0.0195108838, -0.0104003223, -0.0009837818,  0.0087356847,  0.0187546927 

   0.0290693250,  0.0396753438,  0.0505682528,  0.0617432520,  0.0731955394 

  -0.0849232078, -0.0969054326, -0.1091460735, -0.1216373071, -0.1343720406 

  -0.1473424733, -0.1605402082, -0.1739567965, -0.1875831038, -0.2014097124 

  -0.2154271752, -0.2296251506, -0.2439934313, -0.2585212290, -0.2731975317 

  -0.2880111337, -0.3029502928, -0.3180032372, -0.3331578076, -0.3484017253 

  -0.3637222052, -0.3791064322, -0.3945416212, -0.4100143015, -0.4255111217 

  -0.4410185516, -0.4565227628, -0.4720100164, -0.4874662757, -0.5028775334 

  -0.5182296634, -0.5335084200, -0.5486994982, -0.5637886524, -0.5787616372 

  -0.5936041474, -0.6083019376, -0.6228409410, -0.6372069120, -0.6513859630 

  -0.6653640866, -0.6791275144, -0.6926627755, -0.7059561610, -0.7189947963 

  -0.7317654490, -0.7442554235, -0.7564523220, -0.7683438063, -0.7799182534 

  -0.7911639810, -0.8020697832, -0.8126249313, -0.8228194118, -0.8326428533 

  -0.8420860767, -0.8511404991, -0.8597975969, -0.8680517077, -0.8758881092 

  -0.8832823634, -0.8902196884, -0.8967157602, -0.9027729034, -0.9083824754 

  -0.9135394692, -0.9182395935, -0.9224776030, -0.9262499809, -0.9295535684 

  -0.9323854446, -0.9347436428, -0.9366261959, -0.9380323887, -0.9389615655 

  -0.9394137263, -0.9393896461, -0.9388904572, -0.9379178882, -0.9364743829 

  -0.9345626831, -0.9321863055, -0.9293491840, -0.9260557890, -0.9223110080 

  -0.9181203246, -0.9134896994, -0.9084255695, -0.9029349089, -0.8970250487 

  -0.8907034993, -0.8839784265, -0.8768582940, -0.8693521619, -0.8614694476 

  -0.8532197475, -0.8446131349, -0.8356599212, -0.8263708353, -0.8167568445 

  -0.8068289757, -0.7965991497, -0.7860788107, -0.7752800584, -0.7642148733 

  -0.7528960109, -0.7413358092, -0.7295469642, -0.7175422311, -0.7053351402 

  -0.6929380894, -0.6803644896, -0.6676273942, -0.6547405124, -0.6417166591 

  -0.6285686493, -0.6153115034, -0.6019562483, -0.5885198116, -0.5750215650 

   0.5615197420,  0.5478612781,  0.5341838002,  0.5204906464,  0.5067980289 

   0.4931168854,  0.4794588387,  0.4658361673,  0.4522601366,  0.4387422502 

   0.4252935350,  0.4119254053,  0.3986486793,  0.3854739666,  0.3724119067 

   0.3594728410,  0.3466667533,  0.3340034485,  0.3214924335,  0.3091430366 

   0.2969639599,  0.2849639654,  0.2731511295,  0.2615332901,  0.2501178682 

   0.2389119864,  0.2279221565,  0.2171545923,  0.2066148520,  0.1963084787 

   0.1862401515,  0.1764142811,  0.1668347418,  0.1575049609,  0.1484276950 

   0.1396053135,  0.1310400218,  0.1227331311,  0.1146853194,  0.1068974212 

   0.0993694067,  0.0921007246,  0.0850901082,  0.0783365741,  0.0718384907 

   0.0655927584,  0.0595967993,  0.0538481586,  0.0483424664,  0.0430756323 

   0.0380428955,  0.0332404599,  0.0286619961,  0.0242999699,  0.0201510899 

   0.0162059069,  0.0124559226,  0.0088928537,  0.0054926532,  0.0023052765 

  -0.0005515143, -0.0030201224, -0.0052712574, -0.0073737046, -0.0093160523 

  -0.0111072771, -0.0127562135, -0.0142635731, -0.0156361461, -0.0168790054 

  -0.0179969221, -0.0189934950, -0.0198726747, -0.0206398536, -0.0212980714 

  -0.0218509119, -0.0223025978, -0.0226570386, -0.0229178313, -0.0230882075 

  -0.0231725387, -0.0231746566, -0.0230979007, -0.0229462404, -0.0227237809 

  -0.0224345829, -0.0220820960, -0.0216706358, -0.0212045144, -0.0206875466 

  -0.0201238506, -0.0195175279, -0.0188730918, -0.0181944817, -0.0174855441 

  -0.0167510118, -0.0159947462, -0.0152208358, -0.0144332750, -0.0136361914 

  -0.0128338682, -0.0120294262, -0.0112272501, -0.0104311826, -0.0096443929 

  -0.0088709844, -0.0081134979, -0.0073764324, -0.0066623385, -0.0059733889 

  -0.0053142183, -0.0046856776, -0.0040914025, -0.0035321070, -0.0030089030 

  -0.0025271603, -0.0020749648, -0.0016621647, -0.0012705614, -0.0008115423

];

h = h.';

h = h(:);

h(1*120+(1:120)) = -h(1*120+(1:120));

h(3*120+(1:120)) = -h(3*120+(1:120));

h(:) = h(end:-1:1);

 No newline at end of file