Comments CatStream

Author: pschatzmann

examples/tests/fft/fft-ifft/fft-ifft.ino

@@ -0,0 +1,56 @@
+#include "AudioTools.h"
+#include "AudioTools/AudioLibs/AudioRealFFT.h" // using RealFFT
+
+AudioInfo info(44100, 1, 16);
+AudioRealFFT fft; // or AudioKissFFT
+Hann hann;
+BufferedWindow buffered(&hann);
+SineWaveGenerator<int16_t> sineWave(32000);
+GeneratedSoundStream<int16_t> in(sineWave);
+StreamCopy copier(fft, in);
+CsvStream<int16_t> out(Serial);
+StreamCopy copierOut(out, fft);
+float value = 0;
+
+// display fft result
+void fftResult(AudioFFTBase &fft) {
+  float diff;
+  auto result = fft.result();
+  if (result.magnitude > 100) {
+    Serial.print(result.frequency);
+    Serial.print(" ");
+    Serial.print(result.magnitude);
+    Serial.print(" => ");
+    Serial.print(result.frequencyAsNote(diff));
+    Serial.print(" diff: ");
+    Serial.print(diff);
+    Serial.print(" - time ms ");
+    Serial.print(fft.resultTime() - fft.resultTimeBegin());
+    Serial.println();
+  }
+  // execute ifft
+  copierOut.copyAll();
+}
+
+void setup() {
+  Serial.begin(115200);
+  AudioToolsLogger.begin(Serial, AudioToolsLogLevel::Warning);
+
+  // set the frequency
+  sineWave.setFrequency(N_B4);
+
+  // Setup sine wave
+  auto cfg = in.defaultConfig();
+  cfg.copyFrom(info);
+  in.begin(cfg);
+
+  // Setup FFT
+  auto tcfg = fft.defaultConfig(RXTX_MODE);
+  tcfg.window_function = &buffered;
+  fft.begin(tcfg);
+
+  // setup output
+  out.begin(info);
+}
+
+void loop() { copier.copy(); }

src/AudioTools/CoreAudio/BaseStream.h

@@ -176,9 +176,9 @@ class AudioStream : public BaseStream, public AudioInfoSupport, public AudioInfo
 /**
  * @brief Provides data from a concatenation of Streams. Please note that the
  * provided Streams can be played only once! You will need to reset them (e.g.
- * moving the file pointer to the beginning) and readd them back if you want to
+ * moving the file pointer to the beginning) and read them back if you want to
  * process them a second time. The default timeout on the available() method is
- * set to 0. This might be not good if you use e.g. a URLStream.
+ * set to 0. This might be too small if you use e.g. a URLStream.
  * @ingroup io
  * @author Phil Schatzmann
  * @copyright GPLv3
@@ -222,6 +222,8 @@ class CatStream : public BaseStream {
   void setOnEndCallback(void (*callback)(Stream *stream)) {
     end_callback = callback;
   }
+
+  /// Defines the timout the system waits for data when moving to the next stream
   void setTimeout(uint32_t t) { _timeout = t; }
 
   /// not supported