Commit 7792d3cd authored by hmund's avatar hmund
Browse files

restructure code to convert to CLDFB domain

parent 07c78ba8
Loading
Loading
Loading
Loading
+6 −4
Original line number Diff line number Diff line
@@ -54,8 +54,9 @@ end
% convert sphere-sampled HRIRs to SHD HRIRs
hrir_len = 128;
ambi_order = 3;
write_out_sofa = 0;
[sofa_path,sofa_name, sofa_ext] = fileparts(sofa_file);
IR = generate_HOA_HRIRs_MOD_lens(ambi_order, py_path, sofa_path, [sofa_name,sofa_ext], hrir_len);
IR = generate_HOA_HRIRs_MOD_lens(ambi_order, py_path, sofa_path, [sofa_name,sofa_ext], hrir_len, write_out_sofa);
% load([thispath,'HRIR_128_48000_dolby_SBA3.mat'],'IR'); gives the same data as the above with default sofa file

%% SHD -> CLDFB via least squares error optimization
@@ -63,10 +64,11 @@ IR = generate_HOA_HRIRs_MOD_lens(ambi_order, py_path, sofa_path, [sofa_name,sofa
num_cldfb_taps = 3;
IR_cldfb = zeros(60,num_cldfb_taps,num_ears,num_ch); % 60 frequency bands
eval_flag = 0; % optional, = 1 requires signal processing toolbox (fftfilt)
legacy_flag = 1; % = 1 used to indicate slightly too short buffers as used to generate tested coefficients 
for pos = 1:num_ch
   disp(['Channel ',num2str(pos),'/',num2str(num_ch)])
   for ear = 1:num_ears
      IR_cldfb(:,:,ear,pos) = fir_to_cldfb_fir( IR(:,ear,pos), num_cldfb_taps, eval_flag );
      IR_cldfb(:,:,ear,pos) = fir_to_cldfb_fir( IR(:,ear,pos), num_cldfb_taps, eval_flag, legacy_flag );
   end
end

@@ -98,13 +100,13 @@ writeData3L(fid, ['const float rightHRIRImag_' order '[BINAURAL_CONVBANDS][' ord
fclose(fid);
rmpath(fullfile(thispath,'..','param_bin'));

function F = fir_to_cldfb_fir( target_fir, num_cldfb_taps, eval_flag )
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 
%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
+300 −0
Original line number Diff line number Diff line
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% 
%    (C) 2022-2023 Baseline Development Group with portions copyright Dolby International AB, Ericsson AB,
%    Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V., Huawei Technologies Co. LTD.,
%    Koninklijke Philips N.V., Nippon Telegraph and Telephone Corporation, Nokia Technologies OY, Orange,
%    Panasonic Corporation, Qualcomm Technologies, Inc., VoiceAge Corporation. All Rights Reserved.
% 
%    This software is protected by copyright law and by international treaties.
%    The Baseline Development Group consisting of Dolby International AB, Ericsson AB,
%    Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V., Huawei Technologies Co. LTD.,
%    Koninklijke Philips N.V., Nippon Telegraph and Telephone Corporation, Nokia Technologies OY, Orange,
%    Panasonic Corporation, Qualcomm Technologies, Inc., and VoiceAge Corporation retain full ownership
%    rights in their respective contributions in the software. No license of any kind, including but not
%    limited to patent license, of any foregoing parties is hereby granted by implication, estoppel or
%    otherwise.
% 
%    This software is provided "AS IS", without any express or implied warranties. The software is in the
%    development stage. It is intended exclusively for experts who have experience with such software and
%    solely for the purpose of inspection. All implied warranties of non-infringement, merchantability
%    and/or fitness for a particular purpose are hereby disclaimed and excluded.
% 
%    Any dispute, controversy or claim arising under or in relation to providing this software shall be
%    submitted to and settled by the final, binding jurisdiction of the courts of Munich, Germany in
%    accordance with the laws of the Federal Republic of Germany excluding its conflict of law rules and
%    the United Nations Convention on Contracts on the International Sales of Goods.
% 
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
function F = fir_to_cldfb_fir( target_fir, num_cldfb_taps, eval_flag, legacy_flag )
% F = fir_to_cldfb_fir( target_fir, num_cldfb_taps, eval_flag, legacy_flag )
%
% computes complex-valued FIR coefficients to be applied in the CLDFB analysis domain 
% which approximate time domain filtering with given target FIR coefficients 
% in a least squares sense.

[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