Add support for LRC Lyrics

README.md

@@ -81,8 +81,13 @@ Following tag header formats are supported:
 - [RIFF](https://wikipedia.org/wiki/Resource_Interchange_File_Format)/INFO
 - [Vorbis comment](https://wikipedia.org/wiki/Vorbis_comment)
 - [AIFF](https://wikipedia.org/wiki/Audio_Interchange_File_Format)
-
-It allows many tags to be accessed in audio format, and tag format independent way.
+
+Following lyric formats are supported:
+- [LRC](https://en.wikipedia.org/wiki/LRC_(file_format))
+- Synchronized lyrics (SYLT)
+- Unsynchronized lyrics (USULT)
+[
+It allows many tags to be]() accessed in audio format, and tag format independent way.
 
 Support for [MusicBrainz](https://musicbrainz.org/) tags as written by [Picard](https://picard.musicbrainz.org/).
 [ReplayGain](https://wiki.hydrogenaud.io/index.php?title=ReplayGain) tags are supported.

lib/common/MetadataCollector.ts

@@ -11,6 +11,7 @@ import { CombinedTagMapper } from './CombinedTagMapper.js';
 import { CommonTagMapper } from './GenericTagMapper.js';
 import { toRatio } from './Util.js';
 import { fileTypeFromBuffer } from 'file-type';
+import { parseLrc } from '../lrc/LyricsParser.js';
 
 const debug = initDebug('music-metadata:collector');
 
@@ -265,6 +266,12 @@ export class MetadataCollector implements INativeMetadataCollector {
         }
         break;
 
+      case 'lyrics':
+        if (typeof tag.value === 'string') {
+          tag.value = parseLrc(tag.value);
+        }
+        break;
+
       default:
       // nothing to do
     }

lib/lrc/LyricsParser.ts

@@ -0,0 +1,39 @@
+import { type ILyricsText, type ILyricsTag, LyricsContentType, TimestampFormat } from '../type.js';
+
+/**
+ * Parse LRC (Lyrics) formatted text
+ * Ref: https://en.wikipedia.org/wiki/LRC_(file_format)
+ * @param lrcString
+ */
+export function parseLrc(lrcString: string): ILyricsTag {
+  const lines = lrcString.split('\n');
+  const syncText: ILyricsText[] = [];
+
+  // Regular expression to match LRC timestamps (e.g., [00:45.52])
+  const timestampRegex = /\[(\d{2}):(\d{2})\.(\d{2})\]/;
+
+  for (const line of lines) {
+    const match = line.match(timestampRegex);
+
+    if (match) {
+      const minutes = Number.parseInt(match[1], 10);
+      const seconds = Number.parseInt(match[2], 10);
+      const hundredths = Number.parseInt(match[3], 10);
+
+      // Convert the timestamp to milliseconds, as per TimestampFormat.milliseconds
+      const timestamp = (minutes * 60 + seconds) * 1000 + hundredths * 10;
+
+      // Get the text portion of the line (e.g., "あの蝶は自由になれたかな")
+      const text = line.replace(timestampRegex, '').trim();
+
+      syncText.push({ timestamp, text });
+    }
+  }
+
+  // Creating the ILyricsTag object
+  return {
+    contentType: LyricsContentType.lyrics,
+    timeStampFormat: TimestampFormat.milliseconds,
+    syncText,
+  };
+}

lib/type.ts

@@ -716,7 +716,7 @@ export interface IRandomReader {
   randomRead(buffer: Uint8Array, offset: number, length: number, position: number): Promise<number>;
 }
 
-interface ILyricsText {
+export interface ILyricsText {
   text: string;
   timestamp?: number;
 }

package.json

@@ -85,7 +85,9 @@
     "info",
     "parse",
     "parser",
-    "bwf"
+    "bwf",
+    "slt",
+    "lyrics"
   ],
   "scripts": {
     "clean": "del-cli 'lib/**/*.js' 'lib/**/*.js.map' 'lib/**/*.d.ts' 'src/**/*.d.ts' 'test/**/*.js' 'test/**/*.js.map' 'test/**/*.js' 'test/**/*.js.map' 'doc-gen/**/*.js' 'doc-gen/**/*.js.map'",

test/test-file-flac.ts

@@ -3,6 +3,7 @@ import fs from 'node:fs';
 import * as path from 'node:path';
 
 import * as mm from '../lib/index.js';
+import { LyricsContentType, TimestampFormat } from '../lib/index.js';
 import { Parsers } from './metadata-parsers.js';
 import { samplePath } from './util.js';
 
@@ -173,5 +174,27 @@ describe('Parse FLAC Vorbis comment', () => {
     assert.equal(mm.ratingToStars(common.rating[0].rating), 4, 'Vorbis tag rating conversion');
   });
 
+  it('Should decode LRC lyrics', async () => {
+
+    const filePath = path.join(flacFilePath, 'Dance In The Game - ZAQ - LRC.flac');
+    const {common} = await mm.parseFile(filePath);
+
+    assert.isArray(common.lyrics, 'common.lyrics');
+    assert.strictEqual(common.lyrics.length, 1, 'common.lyrics.length');
+    const lrcLyrics = common.lyrics[0];
+    assert.strictEqual(lrcLyrics.contentType, LyricsContentType.lyrics, 'lrcLyrics.contentType');
+    assert.strictEqual(lrcLyrics.timeStampFormat, TimestampFormat.milliseconds, 'lrcLyrics.timeStampFormat');
+    assert.isArray(lrcLyrics.syncText, 'lrcLyrics.syncText');
+    assert.strictEqual(lrcLyrics.syncText.length, 39, 'lrcLyrics.syncText.length');
+    assert.strictEqual(lrcLyrics.syncText[0].timestamp, 0, 'syncText[0].timestamp');
+    assert.strictEqual(lrcLyrics.syncText[0].text, '作词 : ZAQ', 'lrcLyrics.syncText[0].text');
+    assert.strictEqual(lrcLyrics.syncText[1].timestamp, 300, 'syncText[1].timestamp');
+    assert.strictEqual(lrcLyrics.syncText[1].text, '作曲 : ZAQ', 'lrcLyrics.syncText[1].text');
+
+    const syncText = lrcLyrics.syncText
+    assert.isArray(common.lyrics, 'common.lyrics');
+
+  });
+
 });