mirror of
https://github.com/mborgerding/kissfft.git
synced 2025-05-27 21:20:27 -04:00
47 lines
1.2 KiB
Matlab
Executable File
47 lines
1.2 KiB
Matlab
Executable File
function snr= testkiss( nfft , prec )
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if strcmp( prec ,'short')
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scale_t2f=nfft;
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scale_f2t=nfft;
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else
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scale_t2f=1;
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scale_f2t=1/nfft;
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endif
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kfft= sprintf('./fftutil_%s',prec);
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siglen = nfft;
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sig=floor(32767*rand(1,siglen)) + j*floor(32767*rand(1,siglen));
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filesave('time.dat',prec,sig);
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cmd = sprintf('%s -n %d time.dat freq.dat',kfft,nfft);
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system(cmd);
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Fsigcomp=fileload('freq.dat',prec,1) * scale_t2f;
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Fsig=fft(sig);
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%x=linspace(0,2*pi*(nfft-1)/nfft,nfft);
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%plot(x,abs(Fsig),'r',x,abs(Fsigcomp),'g')
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diff = Fsig - Fsigcomp;
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noise_pow = sum( conj(diff).*diff );
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sig_pow = sum( conj(Fsig).*Fsig );
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snr_t2f = 10*log10( sig_pow / noise_pow )
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avg_scale = mean( abs(Fsig) ./ abs(Fsigcomp) );
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var_scale = var( abs(Fsig) ./ abs(Fsigcomp) );
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cmd = sprintf('%s -i -n %d freq.dat time2.dat',kfft,nfft);
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system(cmd);
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sigcomp=fileload('time2.dat',prec,1) * scale_f2t;
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%sig=ifft(Fsigcomp);
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diff = sig - sigcomp;
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noise_pow = sum( conj(diff).*diff );
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sig_pow = sum( conj(sig).*sig );
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snr_f2t = 10*log10( sig_pow / noise_pow )
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avg_scale = mean( abs(sig) ./ abs(sigcomp) );
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var_scale = var( abs(sig) ./ abs(sigcomp) );
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snr=[snr_t2f snr_f2t];
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endfunction
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