I2S

Author: pschatzmann

.DS_Store

@@ -2,13 +2,15 @@
 
 Some basic C++ classes that can be used for Audio Processing privided as Arduino Library
 
+- Additinal Stream implementations: MemoryStream, UrlStream [ESP32 only]
 - a simple I2S class (to read and write to the internal I2S) [ESP32 only]
 - a simple ADC class (to read analog data with the help of I2S) [ESP32 only]
 - Converters
-- Notes (Frequencies of notes)
+- Musical Notes (with Frequencies of notes)
 - SineWaveGenerator (to generate some sine tone)
 - NBuffer (Multi buffer for writing and reading of (sound) data)
 - TimerAlarmRepeating (e.g. for sampling sound data using exact times) [ESP32 only]
+- A Wav Encoder and Decoder
 
 This functionality provides the glue which makes different sound processing components and libraries work together.
 We also provide plenty of examples that demonstrate how to implement the different scenarios.
@@ -41,6 +43,15 @@ Here is the generated [Class documentation](https://pschatzmann.github.io/arduin
 
 ## Project Status
 
-This is currently work in progress. 
-
+This is currently work in progress:
+
+| Functionality          | Status
+|-----------------------------------
+| Analog input - ADC     | tested 
+| I2S                    | tested
+| Files                  | open
+| Streams                | open
+| WAV encoding/deconding | open               
+| AAC encoding/deconding | open               
+| int24_t                | open               
 

License.txt

@@ -11,7 +11,7 @@ using namespace sound_tools;
 ADC adc;
 BluetoothA2DPSource a2dp_source;
 // The data has a center of around 26427, so we we need to shift it down to bring the center to 0
-FilterScaler<int16_t> scaler(1.0, -26427, 32700 );
+<int16_t> scaler(1.0, -26427, 32700 );
 
 // callback used by A2DP to provide the sound data
 int32_t get_sound_data(Channels* data, int32_t len) {

README.md

@@ -14,10 +14,10 @@ The INMP441 is a high-performance, low power, digital-output, omnidirectional ME
 | --------| ---------------
 | VDD     |  3.3
 | GND     |  GND
-| SD      |  IN (GPIO23)
+| SD      |  IN (GPIO32)
 | L/R     |  GND
-| WS      |  WS (GPIO25)
-| SCK     |  BCK (GPIO26)
+| WS      |  WS (GPIO15)
+| SCK     |  BCK (GPIO14)
 
 
 SCK: Serial data clock for I²S interface

examples/adc-a2dp/adc-a2dp.ino

@@ -14,10 +14,10 @@ The INMP441 is a high-performance, low power, digital-output, omnidirectional ME
 | --------| ---------------
 | VDD     |  3.3
 | GND     |  GND
-| SD      |  IN (GPIO23)
+| SD      |  IN (GPIO32)
 | L/R     |  GND
-| WS      |  WS (GPIO25)
-| SCK     |  BCK (GPIO26)
+| WS      |  WS (GPIO15)
+| SCK     |  BCK (GPIO14)
 
 
 SCK: Serial data clock for I²S interface

examples/i2s-a2dp/README.md

@@ -5,31 +5,32 @@
 using namespace sound_tools;  
 
 /**
- * @brief We use a ADS1015 I2S microphone as input and send the data to A2DP
- * Unfortunatly the data type from the microphone (int32_t)  does not match with the required data type by A2DP (int16_t),
- * so we need to convert.
+ * @brief We use I2S as input and send the data to A2DP
+ * To test we use a INMP441 microphone. 
  */ 
 
 I2S<int32_t> i2s;
 const size_t max_buffer_len = 512;
-int16_t buffer[max_buffer_len][2];
+int32_t buffer[max_buffer_len][2];
 
 // Arduino Setup
 void setup(void) {
   Serial.begin(115200);
 
   // start i2s input with default configuration
   Serial.println("starting I2S...");
-  i2s.begin(i2s.defaultConfig(RX_MODE));
+  I2SConfig<int32_t> config = i2s.defaultConfig(RX_MODE);
+  config.i2s.sample_rate = 16000;
+  i2s.begin(config);
 }
 
 // Arduino loop - repeated processing 
 void loop() {
   size_t len = i2s.read(buffer, max_buffer_len); 
 
   for (int j=0;j<len;j++){
-    Serial.print(buffer[j][0]);
+    Serial.print((int32_t)buffer[j][0]);
     Serial.print(", ");
-    Serial.println(buffer[j][1]);
+    Serial.println((int32_t)buffer[j][1]);
   }
 }

examples/i2s-serial/README.md

@@ -0,0 +1,29 @@
+#include "AudioWAV.h"
+#include "AudioTools.h" 
+#include "AudioToolsESP32.h" 
+
+I2S i2s; // I2S output destination
+WAVDecoder decoder(i2s);  
+UrlStream music;
+
+void setup(){
+    Serial.begin(115200);
+    // connect to WIFI
+    WiFi.begin("network name", "password");
+    while (WiFi.status() != WL_CONNECTED) {
+      delay(500);
+      Serial.print(".");
+    }
+
+    music.begin("https://www2.cs.uic.edu/~i101/SoundFiles/BabyElephantWalk60.wav");
+    i2s.begin();
+    decoder.begin();
+}
+
+void loop(){
+    static uint8_t buffer[512];
+    if (music.available()>0){
+        int len = music.readBytes(buffer, 512);
+        decoder.write(buffer, len);
+    }
+}

examples/i2s-serial/i2s-serial.ino

@@ -0,0 +1,42 @@
+/**
+ * @file aac_encode.ino
+ * @author Phil Schatzmann
+ * @brief Encode pwm data to AAC Stream (SD file)
+ * @version 0.1
+ * @date 2021-01-24
+ * 
+ * @copyright Copyright (c) 2021
+ * 
+ */
+#include <SPI.h>
+#include <SD.h>
+#include "WAVEncoder.h"
+#include "StarWars30.h"
+#include "AudioTools.h"
+
+File dataFile = SD.open("example.wav", FILE_WRITE); 
+WAVEncoder encoder(dataFile);
+MemoryStream music(StarWars30_raw, StarWars30_raw_len);
+
+void setup(){
+    Serial.begin(115200);
+    SD.begin(); 
+
+    // setup encoder
+    encoder.begin();
+    Serial.println("Creating WAV file...");
+}
+
+void loop(){
+    static uint8_t buffer[512];
+    if (dataFile){
+        if (music.available()>0){
+            int len = music.readBytes(buffer, 512);
+            encoder.write(buffer, len);
+        } else {
+            // no more data -> close file
+            dataFile.close();
+            Serial.println("File has been closed");
+        }
+    }
+}