sof/tools/tune/eq/eq_iir_blob_decode.m

123 lines
3.1 KiB
Matlab

function eq = eq_iir_blob_decode(ublob, resp_n)
%% Decode an IIR EQ binary blob
%
% eq = eq_fir_decode_blob(blobfn, resp_n)
%
% blob - EQ setup blob 32 bit data vector
% resp_n - index of response to decode
% fs - sample rate, optional
% do_plot - set to 1 for frequency response plot, optional
%
% Returned struct fields
% b - numerator coefficients
% a - denominator coefficients
% channels_in_config - numbers of channels in blob
% assign response - vector of EQ indexes assigned to channels
%
% To decode a IIR blob, try iirst
% eq_blob_plot('../../topology/topology1/m4/eq_iir_coef_loudness.m4', 'iir');
% eq_blob_plot('../../ctl/eq_iir_loudness.bin', 'iir');
% eq_blob_plot('../../ctl/eq_iir_loudness.txt', 'iir');
% SPDX-License-Identifier: BSD-3-Clause
%
% Copyright (c) 2016-2020, Intel Corporation. All rights reserved.
%
% Author: Seppo Ingalsuo <seppo.ingalsuo@linux.intel.com>
if nargin < 2
verbose = 1;
resp_n = [];
else
verbose = 0;
end
%% Get ABI information
[abi_bytes, nbytes_abi] = eq_get_abi(0);
%% Defaults
eq.b = [];
eq.a = [];
eq.channels_in_config = 0;
eq.number_of_responses = 0;
eq.assign_response = [];
%% Decode
blob = double(ublob);
abi = nbytes_abi / 4;
eq.size = blob(abi + 1);
eq.channels_in_config = blob(abi + 2);
eq.number_of_responses = blob(abi + 3);
reserved1 = blob(abi + 4);
reserved2 = blob(abi + 5);
reserved3 = blob(abi + 6);
reserved4 = blob(abi + 7);
eq.assign_response = signedint(blob(abi + 8:abi + 8 + eq.channels_in_config - 1), 32);
if verbose
fprintf('Blob size = %d\n', eq.size);
fprintf('Channels in config = %d\n', eq.channels_in_config);
fprintf('Number of responses = %d\n', eq.number_of_responses);
fprintf('Assign responses =');
for i=1:length(eq.assign_response)
fprintf(' %d', eq.assign_response(i));
end
fprintf('\n');
end
% Just header request
if isempty(resp_n)
eq.b = [];
eq.a = [];
return
end
% Handle pass-through
if resp_n < 0
eq.b = 1;
eq.a = 1;
end
% Normal filter taps retrieve
if resp_n > eq.number_of_responses-1;
error('Request of non-available response');
end
n_blob_header = 7;
n_iir_header = 6;
n_iir_section = 7;
j = abi + n_blob_header + eq.channels_in_config + 1;
eq.b = 1.0;
eq.a = 1.0;
for i=1:eq.number_of_responses
num_sections = blob(j);
section_length = num_sections * n_iir_section + n_iir_header;
if i-1 == resp_n
k = j + n_iir_header;
for j=1:num_sections
ai = signedint(blob(k+1:-1:k),32)';
bi = signedint(blob(k+4:-1:k+2),32)';
shifti = signedint(blob(k+5),32);
gaini = signedint(blob(k+6),16);
b0 = bi/2^30;
a0 = [1 -(ai/2^30)];
gain = gaini/2^14;
b0 = b0 * 2^(-shifti) * gain;
eq.b = conv(eq.b, b0);
eq.a = conv(eq.a, a0);
k = k + n_iir_section;
end
end
j = j+section_length;
end
end
function y = signedint(x, bits)
y = x;
idx = find(x > 2^(bits-1)-1);
y(idx) = x(idx)-2^bits;
end