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+#X msg 31 411 \; pd dsp 1;
+#X obj 15 8 block~ 512;
+#X text 225 131 tabreceive~ outputs array contents \,;
+#X text 225 149 constantly \, every block. Here it's;
+#X text 223 169 used to get the Hann window to;
+#X text 225 187 multiply by the input.;
+#X text 120 7 block~ object does no computation but declares this;
+#X text 120 24 window to be operating at a different block size from
+;
+#X text 122 58 Fourier transform.;
+#X text 121 40 the parent window. This determines the size of the;
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+;
+#X obj 15 332 +~;
+#X text 94 308 Take the magnitude by squaring real and imaginary part
+\, adding and taking square root.;
+#X text 110 424 periodically graph the output. It appears every 512
+samples (about 12 milliseconds) but we only update the graph 4 times
+per second. The graph is back on the main (parent) window.;
+#X text 82 215 forward real FFT. Like "fft~" \, but only one inlet
+(for the real part) and only the first half of the output signals are
+used. (The others are determined by symmetry: they're complex conjugates
+of the first half \, in reverse order.) This takes 1/2 the CPU time
+of "fft".;
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+#X text 305 559 updated for Pd version 0.39;
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+#X text 321 373 Hann window;
+#X text 98 462 period 512;
+#X text 40 368 recalculate Hann;
+#X text 75 383 window table;
+#X text 100 233 tens of Hz.;
+#X text 80 215 <- frequency \,;
+#X text 98 270 click here and;
+#X text 170 286 <- see;
+#X text 21 32 In this example we use a sub-patch ("pd fft-analysis")
+to re-block the Fourier transform to 512 points. The signal is multiplied
+by the Hann window function (which is just a raised cosine.) The magnitude
+\, which is computed in the sub-patch \, is graphed below in this window.
+The point at 255 corresponds to just below the Nyquist frequency. Phase
+isn't shown \, and unlike the previous patch we don't control the initial
+phase of the oscillator. (For fun \, try drawing other window functions
+with the mouse...);
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