removed codecs to save memory

lib/ESP32-audioI2S/examples/Synchronised lyrics/README.md

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+# Synchronised lyrics/text
+
+Synchronized Lyrics or also called 'Lyrics3' is a format for storing lyrics in the ID3 metadata of audio files such as MP3s. The synchronized texts are saved in a special ID3 tag called **SYLT**.
+
+Unlike plain lyrics, synced lyrics can contain not only the lyrics of the song, but also information about when each section of lyrics should be displayed. This information is stored in the form of timestamps that indicate when each piece of text should begin and end.
+Once the synced lyrics are stored in the ID3 metadata, they can be viewed by a compatible audio player. The audio player reads the SYLT tags and displays the lyrics of the song in real time while the song is playing. This allows the listener to follow the lyrics of the song in real time and sing along.
+
+@moononournation had the idea of ​​reading the SYLT tag with the audioI2S library, and he also wrote the necessary source code.
+
+The example shown here reads an mp3 file containing the SYLT tag, plays the mp3 file and displays the lyrics according to the timestamps in the serial terminal.

lib/ESP32-audioI2S/examples/Synchronised lyrics/synchronised_lyrics.ino

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+#include "Arduino.h"
+#include "Audio.h"
+#include "SD_MMC.h"
+#include "Ticker.h"
+
+Audio audio;
+Ticker   ticker;
+char     *lyricsText;
+size_t   lyricsTextSize = 0;
+uint16_t lyricsPtr = 0;
+uint32_t timeStamp = 0;
+uint32_t ms = 0;
+char     chbuf[512];
+
+#define I2S_LRC     26
+#define I2S_DOUT    25
+#define I2S_BCLK    27
+#define I2S_MCLK     0
+
+#define SD_MMC_D0    2
+#define SD_MMC_CLK  14
+#define SD_MMC_CMD  15
+
+
+size_t bigEndian(char* base, uint8_t numBytes, uint8_t shiftLeft = 8){
+    uint64_t result = 0;
+    if(numBytes < 1 || numBytes > 8) return 0;
+    for (int i = 0; i < numBytes; i++) {
+            result += *(base + i) << (numBytes -i - 1) * shiftLeft;
+    }
+    if(result > SIZE_MAX) {log_e("range overflow"); result = 0;} // overflow
+    return (size_t)result;
+}
+
+void tckr(){ // caller every 100ms
+    if(audio.isRunning()){
+        ms += 100;
+        if(ms >= timeStamp){
+            Serial.print(chbuf);
+            strcpy(chbuf, lyricsText + lyricsPtr); lyricsPtr += strlen(chbuf) + 1; // strlen + '\0'
+            timeStamp = bigEndian(lyricsText + lyricsPtr, 4); lyricsPtr += 4;
+        }
+    }
+    else{
+        if(lyricsText) {free(lyricsText); lyricsText = NULL; lyricsTextSize = 0;}
+
+        ticker.detach();
+    }
+}
+
+void setup() {
+    pinMode(SD_MMC_D0, INPUT_PULLUP);
+    Serial.begin(115200);
+    if(!SD_MMC.begin( "/sdcard", true, false, 20000)){
+        Serial.println("Card Mount Failed");
+        return;
+    }
+    audio.setPinout(I2S_BCLK, I2S_LRC, I2S_DOUT);
+    audio.setVolume(10); // 0...21
+    audio.connecttoFS(SD_MMC, "/Little London Girl(lyrics).mp3");
+}
+
+void loop(){
+    vTaskDelay(1);
+    audio.loop();
+}
+
+// optional
+void audio_info(const char *info){
+    Serial.print("info        "); Serial.println(info);
+}
+void audio_id3data(const char *info){  //id3 metadata
+//    if(strncmp(info, "Year: ", 6) == 0) Serial.println(info + 6);
+    Serial.print("id3data     ");Serial.println(info);
+}
+void audio_eof_mp3(const char *info){  //end of file
+    Serial.print("eof_mp3     ");Serial.println(info);
+}
+
+void audio_id3lyrics(File &file, const size_t pos, const size_t size) {
+    Serial.printf("\naudio_id3lyrics, pos: %d, size: %d\n", pos, size);
+    lyricsText = (char *)malloc(size);
+    lyricsTextSize = size;
+    file.seek(pos);
+    file.read((uint8_t *)lyricsText, size);
+    Serial.printf("text encoding: %i\n", lyricsText[0]); // 0: ASCII, 3: UTF-8
+    char lang[14]; memcpy(lang, (const char*)lyricsText + 1, 3); lang[3] = '\0'; Serial.printf("language: %s\n", lang);
+    Serial.printf("time stamp format: %i\n", lyricsText[4]);
+    Serial.printf("content type: %i\n", lyricsText[5]);
+    Serial.printf("content descriptor: %i\n\n", lyricsText[6]);
+    lyricsPtr = 7;
+    strcpy(chbuf, lyricsText + lyricsPtr); lyricsPtr += strlen(chbuf) + 1; // strlen + '\0'
+    timeStamp = bigEndian(lyricsText + lyricsPtr, 4);
+    ticker.attach(0.1, tckr); lyricsPtr += 4;
+}
+