DRAFT FFT update

pschatzmann · Aug 6, 2024 · c9ae03f · c9ae03f
1 parent ec00cc1
commit c9ae03f
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Showing 4 changed files with 45 additions and 3 deletions.
diff --git a/src/AudioLibs/AudioEspressifFFT.h b/src/AudioLibs/AudioEspressifFFT.h
@@ -67,6 +67,34 @@ class FFTDriverEspressifFFT : public FFTDriver {
             }
         };
 
+        void rfft() override {
+            conjugate();
+            ret = dsps_fft2r_fc32(p_data, len);
+            if (ret  != ESP_OK){
+                LOGE("dsps_fft2r_fc32 %d", ret);
+            }
+            conjugate();
+            // Bit reverse 
+            ret = dsps_bit_rev_fc32(p_data, len);
+            if (ret  != ESP_OK){
+                LOGE("dsps_bit_rev_fc32 %d", ret);
+            }
+            // Convert one complex vector to two complex vectors
+            ret = dsps_cplx2reC_fc32(p_data, len);
+            if (ret  != ESP_OK){
+                LOGE("dsps_cplx2reC_fc32 %d", ret);
+            }
+        }
+
+        void conjugate(){
+            FFTBin bin;
+            for (int j=0;j<len;j++){
+                getBin(j, bin);
+                bin.conjugate();
+                setBin(j, bin);
+            }
+        }
+
         float magnitude(int idx) override { 
             return sqrt(magnitudeFast(idx));
         }
@@ -88,8 +116,9 @@ class FFTDriverEspressifFFT : public FFTDriver {
             return true;
         }
 
+        bool isReverseFFT() override {return true;}
 
-        virtual bool isValid() override{ return p_data!=nullptr && ret==ESP_OK; }
+        bool isValid() override{ return p_data!=nullptr && ret==ESP_OK; }
 
         esp_err_t ret;
         float *p_data = nullptr;

diff --git a/src/AudioLibs/AudioFFT.h b/src/AudioLibs/AudioFFT.h
@@ -70,6 +70,11 @@ struct FFTBin {
         real *= f;
         img *= f;
     }
+
+    void conjugate(){
+        img = -img;
+    }
+
     void clear() {
         real = img = 0.0f;
     }
@@ -320,6 +325,14 @@ class AudioFFTBase : public AudioOutput {
             return p_magnitudes;
         }
 
+        /// sets the value of a bin
+        bool setBin(int idx, float real, float img) {return p_driver->setBin(idx, real, img);}
+        /// sets the value of a bin
+        bool setBin(int pos, FFTBin &bin) { return p_driver->setBin(pos, bin.real, bin.img);}
+        /// gets the value of a bin
+        bool getBin(int pos, FFTBin &bin) { return p_driver->getBin(pos, bin);}        
+
+
         /// Provides the actual configuration
         AudioFFTConfig &config() {
             return cfg;

diff --git a/src/AudioLibs/AudioRealFFT.h b/src/AudioLibs/AudioRealFFT.h
@@ -63,7 +63,7 @@ class FFTDriverRealFFT : public FFTDriver {
             return (p_x[idx] * p_x[idx] + p_f[idx] * p_f[idx]);
         }
 
-        virtual bool isValid() override{ return p_fft_object!=nullptr; }
+        bool isValid() override{ return p_fft_object!=nullptr; }
 
         /// get Real value
         float getValue(int idx) override { return p_x[idx];}

diff --git a/src/AudioLibs/SDDirect.h b/src/AudioLibs/SDDirect.h
@@ -12,7 +12,7 @@ namespace audio_tools {
 /**
  * @brief We access the files directy with an index. The index is determined by
  * a recurseve tree walk thru the directory. Unfortunatly the SDTFAT library has
- * it's own API which is incompatible with the SDT API
+ * it's own API which is incompatible with the SD API
  */
 template <class SDT, class FileT>
 class SDDirect {