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-rw-r--r--demos/spectrum/3rdparty/fftreal/testapp.dpr150
1 files changed, 150 insertions, 0 deletions
diff --git a/demos/spectrum/3rdparty/fftreal/testapp.dpr b/demos/spectrum/3rdparty/fftreal/testapp.dpr
new file mode 100644
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+++ b/demos/spectrum/3rdparty/fftreal/testapp.dpr
@@ -0,0 +1,150 @@
+program testapp;
+{$APPTYPE CONSOLE}
+uses
+ SysUtils,
+ fftreal in 'fftreal.pas',
+ Math,
+ Windows;
+
+var
+ nbr_points : longint;
+ x, f : pflt_array;
+ fft : TFFTReal;
+ i : longint;
+ PI : double;
+ areal, img : double;
+ f_abs : double;
+ buffer_size : longint;
+ nbr_tests : longint;
+ time0, time1, time2 : int64;
+ timereso : int64;
+ offset : longint;
+ t0, t1 : double;
+ nbr_s_chn : longint;
+ tempp1, tempp2 : pflt_array;
+
+begin
+ (*______________________________________________
+ *
+ * Exactness test
+ *______________________________________________
+ *)
+
+ WriteLn('Accuracy test:');
+ WriteLn;
+
+ nbr_points := 16; // Power of 2
+ GetMem(x, nbr_points * sizeof_flt);
+ GetMem(f, nbr_points * sizeof_flt);
+ fft := TFFTReal.Create(nbr_points); // FFT object initialized here
+
+ // Test signal
+ PI := ArcTan(1) * 4;
+ for i := 0 to nbr_points-1 do
+ begin
+ x^[i] := -1 + sin (3*2*PI*i/nbr_points)
+ + cos (5*2*PI*i/nbr_points) * 2
+ - sin (7*2*PI*i/nbr_points) * 3
+ + cos (8*2*PI*i/nbr_points) * 5;
+ end;
+
+ // Compute FFT and IFFT
+ fft.do_fft(f, x);
+ fft.do_ifft(f, x);
+ fft.rescale(x);
+
+ // Display the result
+ WriteLn('FFT:');
+ for i := 0 to nbr_points div 2 do
+ begin
+ areal := f^[i];
+ if (i > 0) and (i < nbr_points div 2) then
+ img := f^[i + nbr_points div 2]
+ else
+ img := 0;
+
+ f_abs := Sqrt(areal * areal + img * img);
+ WriteLn(Format('%5d: %12.6f %12.6f (%12.6f)', [i, areal, img, f_abs]));
+ end;
+
+ WriteLn;
+ WriteLn('IFFT:');
+ for i := 0 to nbr_points-1 do
+ WriteLn(Format('%5d: %f', [i, x^[i]]));
+
+ WriteLn;
+
+ FreeMem(x);
+ FreeMem(f);
+ fft.Free;
+
+
+ (*______________________________________________
+ *
+ * Speed test
+ *______________________________________________
+ *)
+
+ WriteLn('Speed test:');
+ WriteLn('Please wait...');
+ WriteLn;
+
+ nbr_points := 1024; // Power of 2
+ buffer_size := 256*nbr_points; // Number of flt_t (float or double)
+ nbr_tests := 10000;
+
+ assert(nbr_points <= buffer_size);
+ GetMem(x, buffer_size * sizeof_flt);
+ GetMem(f, buffer_size * sizeof_flt);
+ fft := TFFTReal.Create(nbr_points); // FFT object initialized here
+
+ // Test signal: noise
+ for i := 0 to nbr_points-1 do
+ x^[i] := Random($7fff) - ($7fff shr 1);
+
+ // timing
+ QueryPerformanceFrequency(timereso);
+ QueryPerformanceCounter(time0);
+
+ for i := 0 to nbr_tests-1 do
+ begin
+ offset := (i * nbr_points) and (buffer_size - 1);
+ tempp1 := f;
+ inc(tempp1, offset);
+ tempp2 := x;
+ inc(tempp2, offset);
+ fft.do_fft(tempp1, tempp2);
+ end;
+
+ QueryPerformanceCounter(time1);
+
+ for i := 0 to nbr_tests-1 do
+ begin
+ offset := (i * nbr_points) and (buffer_size - 1);
+ tempp1 := f;
+ inc(tempp1, offset);
+ tempp2 := x;
+ inc(tempp2, offset);
+ fft.do_ifft(tempp1, tempp2);
+ fft.rescale(x);
+ end;
+
+ QueryPerformanceCounter(time2);
+
+ t0 := ((time1-time0) / timereso) / nbr_tests;
+ t1 := ((time2-time1) / timereso) / nbr_tests;
+
+ WriteLn(Format('%d-points FFT : %.0f us.', [nbr_points, t0 * 1000000]));
+ WriteLn(Format('%d-points IFFT + scaling: %.0f us.', [nbr_points, t1 * 1000000]));
+
+ nbr_s_chn := Floor(nbr_points / ((t0 + t1) * 44100 * 2));
+ WriteLn(Format('Peak performance: FFT+IFFT on %d mono channels at 44.1 KHz (with overlapping)', [nbr_s_chn]));
+ WriteLn;
+
+ FreeMem(x);
+ FreeMem(f);
+ fft.Free;
+
+ WriteLn('Press [Return] key to terminate...');
+ ReadLn;
+end.