AudioFFTBase: add frequencyToBin()

Author: pschatzmann

src/AudioTools/AudioLibs/AudioFFT.h

@@ -357,6 +357,12 @@ class AudioFFTBase : public AudioStream {
     return static_cast<float>(bin) * cfg.sample_rate / cfg.length;
   }
 
+  /// Determine the bin number from the frequency
+  int frequencyToBin(int freq){
+    int max_freq = cfg.sample_rate / 2;
+    return map(freq, 0, max_freq, 0, size());
+  }
+
   /// Determines the result values in the max magnitude bin
   AudioFFTResult result() {
     AudioFFTResult ret_value;

tests-cmake/CMakeLists.txt

@@ -24,6 +24,7 @@ add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/resample ${CMAKE_CURRENT_BINARY_DIR
 add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/generator ${CMAKE_CURRENT_BINARY_DIR}/generator)
 add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/effects ${CMAKE_CURRENT_BINARY_DIR}/effects)
 add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/fft ${CMAKE_CURRENT_BINARY_DIR}/fft)
+add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/ifft ${CMAKE_CURRENT_BINARY_DIR}/ifft)
 add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/filter ${CMAKE_CURRENT_BINARY_DIR}/filter)
 add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/filter-wav ${CMAKE_CURRENT_BINARY_DIR}/filter-wav)
 add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/url-test ${CMAKE_CURRENT_BINARY_DIR}/url-test)