Add speak_sd example for issue #149

Add speak_sd example for issue #149

examples/Basics/speak_sd/speak_sd.ino

@@ -0,0 +1,142 @@
+/*
+ * SPDX-FileCopyrightText: 2024 M5Stack Technology CO LTD
+ *
+ * SPDX-License-Identifier: MIT
+ *
+ * Play wav file from SD card
+ *
+ ****************************************************************
+ * Prepare a file named "resources_speak_sd.wav" in the root of your SD card
+ * Wav file format : 44100Hz 16bit mono
+ *
+ * Download it from https://github.com/m5stack/M5Core2/wiki
+ * or you can make it.
+ *   Example of conversion using ffmpeg
+ *   ffmpeg -i input.wav -vn -ac 1 -ar 44100 -acodec pcm_s16le -f wav resources_speak_sd.wav
+ ****************************************************************
+*/
+#include <M5Core2.h>
+
+#define WAV_FILE_NAME "/resources_speak_sd.wav"
+
+File wavFile;
+uint8_t buffer[1024];
+bool play{}, play_loop{true};
+
+struct __attribute__((packed)) wav_header_t {
+    char RIFF[4];
+    uint32_t chunk_size;
+    char WAVEfmt[8];
+    uint32_t fmt_chunk_size;
+    uint16_t audiofmt;
+    uint16_t channel;
+    uint32_t sample_rate;
+    uint32_t byte_per_sec;
+    uint16_t block_size;
+    uint16_t bit_per_sample;
+};
+struct __attribute__((packed)) sub_chunk_t {
+    char identifier[4];
+    uint32_t chunk_size;
+};
+
+// Seek to the beginning of the audio data
+bool seek_file(File& f) {
+    f.seek(0);
+
+    // Read header
+    wav_header_t wheader{};
+    if (f.read((uint8_t*)&wheader, sizeof(wheader)) != sizeof(wheader)) {
+        return false;
+    }
+
+#if 0
+    ESP_LOGI("wav", "RIFF           : %.4s" , wheader.RIFF          );
+    ESP_LOGI("wav", "chunk_size     : %d"   , wheader.chunk_size    );
+    ESP_LOGI("wav", "WAVEfmt        : %.8s" , wheader.WAVEfmt       );
+    ESP_LOGI("wav", "fmt_chunk_size : %d"   , wheader.fmt_chunk_size);
+    ESP_LOGI("wav", "audiofmt       : %d"   , wheader.audiofmt      );
+    ESP_LOGI("wav", "channel        : %d"   , wheader.channel       );
+    ESP_LOGI("wav", "sample_rate    : %d"   , wheader.sample_rate   );
+    ESP_LOGI("wav", "byte_per_sec   : %d"   , wheader.byte_per_sec  );
+    ESP_LOGI("wav", "block_size     : %d"   , wheader.block_size    );
+    ESP_LOGI("wav", "bit_per_sample : %d"   , wheader.bit_per_sample);
+#endif
+
+    // Check format
+    // 44100 16bit mono linear PCM
+    if (memcmp(wheader.RIFF, "RIFF", 4) ||
+        memcmp(wheader.WAVEfmt, "WAVEfmt ", 8) || wheader.audiofmt != 1 ||
+        wheader.sample_rate != 44100 || wheader.bit_per_sample != 16 ||
+        wheader.channel != 1) {
+        Serial.printf("Illegal format");
+        return false;
+    }
+
+    // Find data chunk
+    sub_chunk_t c{};
+    while (true) {
+        if (f.read((uint8_t*)&c, sizeof(c)) != sizeof(c)) {
+            return false;
+        }
+        if (memcmp(c.identifier, "data", 4) == 0) {
+            break;
+        }
+        f.seek(f.position() + c.chunk_size);
+    }
+    return true;
+}
+
+void streaming(File& f) {
+    // No more read
+    if (!f.available()) {
+        // rewind to top (playback loop)
+        if (play_loop) {
+            seek_file(f);
+        }
+        return;
+    }
+    // Read and play
+    auto readed = f.read(buffer, sizeof(buffer));
+    // I2S write is blocking until the end of write
+    M5.Spk.PlaySound(buffer, readed);
+}
+
+void setup() {
+    // LCDEnable,SDEnable,SerialEnable, I2CEnable, mbus_mode_t,SpeakerEnable
+    M5.begin(true, true, true, true, mbus_mode_t::kMBusModeOutput, true);
+
+    M5.Lcd.setTextColor(WHITE);
+    M5.Lcd.setCursor(10, 10);
+    M5.Lcd.printf("Speak Test!");
+
+    wavFile = SD.open(WAV_FILE_NAME);
+    if (!wavFile) {
+        M5.Lcd.clear(TFT_RED);
+        M5.Lcd.setCursor(10, 10);
+        M5.Lcd.printf("Failed to open");
+        while (true) {
+            delay(1000);
+        }
+    }
+
+    play = seek_file(wavFile);
+    if (!play) {
+        M5.Lcd.setCursor(10, 10);
+        M5.Lcd.printf("Illegal format");
+    }
+    M5.Lcd.clear(play ? TFT_DARKGREEN : TFT_PURPLE);
+}
+
+void loop() {
+    if (play) {
+        streaming(wavFile);
+
+        auto pos = M5.Touch.getPressPoint();
+        if (pos.x >= 0 && pos.x < M5.Lcd.width() && pos.y >= 0 &&
+            pos.y < M5.Lcd.height()) {
+            Serial.println("Repeat");
+            seek_file(wavFile);
+        }
+    }
+}