ГО СТ Р 56047— 2014
function EHS = PQmovEHS (xR. xT. X2)
persistent NF Nadv NL M Hw
if (isempty (NL))
NF = 2048:
Nadv = NF / 2:
Fs = 48000:
Fmax = 9000;
NL = 2A(PQ_log2(NF * Fmax / Fs)):
M = NL:
Hw = (1 / M) * sqrt(8 / 3) * PQHannWin (M);
end
EnThr = 8000;
kmax = NL + M -1:
EnRef = xR(Nadv+1:NF-1+1) * xR(Nadv+1:NF-1+1)’:
EnTest = xT(Nadv+1:NF-1+1) * xT(Nadv+1:NF-1+1)’;
if (EnRef < EnThr & EnTest < EnThr)
EHS = -1;
return;
end
D = zeros (1. kmax):
for (k = 0:kmax-1)
D(k+1) = log (X2(2.k+1)/ X2(1.k+1));
end
C = PQ_Corr (D. NL. M);
Cn = PO_NCorr (C. D. NL. M):
Cnm = (1 / NL) * sum (Cn{1 :NL));
Cw = Hw .* (Cn - Cnm);
% DFT
cp = PQRFFT (Cw. NL. 1):
c2 = PQRFFTMSq (cp. NL);
EHS = PQ_FindPeak (c2. Nb’2+1);
%
------------------------------
function tog2 = PQ_log2 (a)
tog2 = 0;
m = 1;
while (m < a)
log2 = log2 ♦ 1;
m = 2 * m;
end
tog2 = log2 -1:
%
-------
function C = PQ_Corr (D. NL. M)
NFFT = 2 * NL:
DO = (D(1:M) zeros(I.NFFT-M)};
D1 = [D(1:M+NL-1)zeros(1.NFFT-(M+NL-1))l;
dO = PQRFFT (DO. NFFT. 1);
d1 = PQRFFT (D1.NFFT. 1);
dx(0+1) = d0(0+1) * d1(0+1):
for (n= 1:NFFT/2-1)
m = NFFT/2 + n;
dx(n+1) = dO(n+1) * d1(n+1) + d0(m+1) * d1(m+1):
dx(m+1) = d0(n+1) * d1(m+1) - d0(m+1) * d1(n+1);
end
dx(NFFT/2+1) = dO(NFFT/2+1) * d1(NFFT/2+1):
46