ajout effets audio

Appli/Core/Src/main.c

@@ -25,6 +25,7 @@
 /* Private includes ----------------------------------------------------------*/
 /* USER CODE BEGIN Includes */
 #include "stm32h7s78_discovery_audio.h"
+#include "audio_effects.h"
 #include <string.h>
 /* USER CODE END Includes */
 
@@ -186,6 +187,8 @@ int main(void)
   fifo_write_idx = FIFO_SIZE / 2;
   fifo_read_idx  = 0;
 
+  AudioEffects_Init();
+
   sDmaConfig.Address    = (uint32_t)adf_buf;
   sDmaConfig.DataLength = AUDIO_SAMPLES * sizeof(int32_t); /* OCTETS */
   sDmaConfig.MsbOnly    = DISABLE;  /* 32-bit/sample ; ENABLE si buffer int16 */
@@ -768,11 +771,17 @@ static void MX_GPIO_Init(void)
 
 /* USER CODE BEGIN 4 */
 
-static inline int16_t adf_sample_to_pcm16(int32_t raw)
+static inline float adf_sample_to_float(int32_t raw)
 {
-	int32_t v = raw >> 8;              // 24 bits -> 16 bits (comme le fait le BSP)
-	if (v > 32767) v = 32767;
-	if (v < -32768) v = -32768;
+	int32_t v = raw >> 8;              // 24 bits -> valeur signee sur 24 bits
+	return (float)v / 8388608.0f;      // normalisation en [-1.0, 1.0]
+}
+
+static inline int16_t float_to_pcm16(float x)
+{
+	float v = x * 32767.0f;
+	if (v > 32767.0f) v = 32767.0f;
+	if (v < -32768.0f) v = -32768.0f;
 	return (int16_t)v;
 }
 
@@ -782,7 +791,9 @@ static void push_to_fifo(int32_t raw)
     {
         return;   // FIFO pleine : on jette l'échantillon plutôt que d'écraser du non-lu
     }
-    int16_t s = adf_sample_to_pcm16(raw);
+    float sample = adf_sample_to_float(raw);
+    sample = AudioEffects_Process(sample);
+    int16_t s = float_to_pcm16(sample);
     uint32_t idx = fifo_write_idx & (FIFO_SIZE - 1);
     audio_fifo[idx * 2]     = s;
     audio_fifo[idx * 2 + 1] = s;