Add support for ID3 metadata in ADTS, make MPEG-TS demuxer more resilient

CLAUDE.md

@@ -2,3 +2,5 @@
 - Code style is tab indent with semicolons
 - Mediabunny core code is contained in src/, extensions are in packages/*/, website is in docs/
 - Tests: Prefer fewer, longer test files over many small ones. Test files should be named after the general catergory of thing that is being tested, not after any individual single test.
+- Avoid ifs without a {} block. So no if (cond) return;, always do if (cond) { return; }
+- `type` instead of `interface` for object types

src/adts/adts-demuxer.ts

@@ -8,9 +8,15 @@
 
 import { aacChannelMap, aacFrequencyTable, AudioCodec } from '../codec';
 import { Demuxer } from '../demuxer';
+import {
+	ID3_V2_HEADER_SIZE,
+	parseId3V2Tag,
+	readId3V2Header,
+} from '../id3';
 import { Input } from '../input';
 import { InputAudioTrack, InputAudioTrackBacking } from '../input-track';
 import { PacketRetrievalOptions } from '../media-sink';
+import { DEFAULT_TRACK_DISPOSITION, MetadataTags } from '../metadata';
 import {
 	assert,
 	AsyncMutex,
@@ -20,7 +26,6 @@ import {
 } from '../misc';
 import { EncodedPacket, PLACEHOLDER_DATA } from '../packet';
 import { readBytes, Reader } from '../reader';
-import { DEFAULT_TRACK_DISPOSITION } from '../metadata';
 import {
 	AdtsFrameHeader,
 	MIN_ADTS_FRAME_HEADER_SIZE,
@@ -43,6 +48,7 @@ export class AdtsDemuxer extends Demuxer {
 	metadataPromise: Promise<void> | null = null;
 	firstFrameHeader: AdtsFrameHeader | null = null;
 	loadedSamples: Sample[] = [];
+	metadataTags: MetadataTags | null = null;
 
 	tracks: InputAudioTrack[] = [];
 
@@ -73,6 +79,26 @@ export class AdtsDemuxer extends Demuxer {
 	}
 
 	async advanceReader() {
+		if (this.lastLoadedPos === 0) {
+			// Skip all ID3v2 tags at the start of the file
+			while (true) {
+				let slice = this.reader.requestSlice(this.lastLoadedPos, ID3_V2_HEADER_SIZE);
+				if (slice instanceof Promise) slice = await slice;
+
+				if (!slice) {
+					this.lastSampleLoaded = true;
+					return;
+				}
+
+				const id3V2Header = readId3V2Header(slice);
+				if (!id3V2Header) {
+					break;
+				}
+
+				this.lastLoadedPos = slice.filePos + id3V2Header.size;
+			}
+		}
+
 		let slice = this.reader.requestSliceRange(
 			this.lastLoadedPos,
 			MIN_ADTS_FRAME_HEADER_SIZE,
@@ -135,7 +161,41 @@ export class AdtsDemuxer extends Demuxer {
 	}
 
 	async getMetadataTags() {
-		return {}; // No tags in this one
+		const release = await this.readingMutex.acquire();
+
+		try {
+			await this.readMetadata();
+
+			if (this.metadataTags) {
+				return this.metadataTags;
+			}
+
+			this.metadataTags = {};
+			let currentPos = 0;
+
+			while (true) {
+				let headerSlice = this.reader.requestSlice(currentPos, ID3_V2_HEADER_SIZE);
+				if (headerSlice instanceof Promise) headerSlice = await headerSlice;
+				if (!headerSlice) break;
+
+				const id3V2Header = readId3V2Header(headerSlice);
+				if (!id3V2Header) {
+					break;
+				}
+
+				let contentSlice = this.reader.requestSlice(headerSlice.filePos, id3V2Header.size);
+				if (contentSlice instanceof Promise) contentSlice = await contentSlice;
+				if (!contentSlice) break;
+
+				parseId3V2Tag(contentSlice, id3V2Header, this.metadataTags);
+
+				currentPos = headerSlice.filePos + id3V2Header.size;
+			}
+
+			return this.metadataTags;
+		} finally {
+			release();
+		}
 	}
 }
 

src/adts/adts-muxer.ts

@@ -7,6 +7,8 @@
  */
 
 import { parseAacAudioSpecificConfig, validateAudioChunkMetadata } from '../codec';
+import { Id3V2Writer } from '../id3';
+import { metadataTagsAreEmpty } from '../metadata';
 import { assert, Bitstream, toUint8Array } from '../misc';
 import { Muxer } from '../muxer';
 import { Output, OutputAudioTrack } from '../output';
@@ -30,7 +32,10 @@ export class AdtsMuxer extends Muxer {
 	}
 
 	async start() {
-		// Nothing needed here
+		if (!metadataTagsAreEmpty(this.output._metadataTags)) {
+			const id3Writer = new Id3V2Writer(this.writer);
+			id3Writer.writeId3V2Tag(this.output._metadataTags);
+		}
 	}
 
 	async getMimeType() {

src/input-format.ts

@@ -266,7 +266,6 @@ export class Mp3InputFormat extends InputFormat {
 		if (!slice) return false;
 
 		let currentPos = 0;
-		let id3V2HeaderFound = false;
 
 		while (true) {
 			let slice = input._reader.requestSlice(currentPos, ID3_V2_HEADER_SIZE);
@@ -278,7 +277,6 @@ export class Mp3InputFormat extends InputFormat {
 				break;
 			}
 
-			id3V2HeaderFound = true;
 			currentPos = slice.filePos + id3V2Header.size;
 		}
 
@@ -287,11 +285,6 @@ export class Mp3InputFormat extends InputFormat {
 			return false;
 		}
 
-		if (id3V2HeaderFound) {
-			// If there was an ID3v2 tag at the start, we can be pretty sure this is MP3 by now
-			return true;
-		}
-
 		currentPos = firstResult.startPos + firstResult.header.totalSize;
 
 		// Fine, we found one frame header, but we're still not entirely sure this is MP3. Let's check if we can find
@@ -441,8 +434,23 @@ export class FlacInputFormat extends InputFormat {
 export class AdtsInputFormat extends InputFormat {
 	/** @internal */
 	async _canReadInput(input: Input) {
+		let currentPos = 0;
+
+		while (true) {
+			let slice = input._reader.requestSlice(currentPos, ID3_V2_HEADER_SIZE);
+			if (slice instanceof Promise) slice = await slice;
+			if (!slice) break;
+
+			const id3V2Header = readId3V2Header(slice);
+			if (!id3V2Header) {
+				break;
+			}
+
+			currentPos = slice.filePos + id3V2Header.size;
+		}
+
 		let slice = input._reader.requestSliceRange(
-			0,
+			currentPos,
 			MIN_ADTS_FRAME_HEADER_SIZE,
 			MAX_ADTS_FRAME_HEADER_SIZE,
 		);
@@ -454,8 +462,10 @@ export class AdtsInputFormat extends InputFormat {
 			return false;
 		}
 
+		currentPos += firstHeader.frameLength;
+
 		slice = input._reader.requestSliceRange(
-			firstHeader.frameLength,
+			currentPos,
 			MIN_ADTS_FRAME_HEADER_SIZE,
 			MAX_ADTS_FRAME_HEADER_SIZE,
 		);

src/metadata.ts

@@ -17,7 +17,7 @@
  * - For Ogg files, there is no global metadata so instead, the metadata refers to the combined metadata of all tracks,
  * in Vorbis-style comment headers.
  * - For WAVE files, the metadata refers to the chunks within the RIFF INFO chunk.
- * - For ADTS files, there is no metadata.
+ * - For ADTS files, the metadata refers to the ID3v2 tags.
  * - For FLAC files, the metadata lives in Vorbis style in the Vorbis comment block.
  * - For MPEG-TS files, metadata tags are currently not supported.
  *
@@ -70,6 +70,7 @@ export type MetadataTags = {
 	 * values. Additionally, all attached files (such as font files) are included here, where the key corresponds to
 	 * the FileUID and the value is an {@link AttachedFile}.
 	 * - MP3: The ID3v2 tags, or a single `'TAG'` key with the contents of the ID3v1 tag.
+	 * - ADTS: The ID3v2 tags.
 	 * - Ogg: The key-value string pairs from the Vorbis-style comment header (see RFC 7845, Section 5.2).
 	 * Additionally, the `'vendor'` key refers to the vendor string within this header.
 	 * - WAVE: The individual metadata chunks within the RIFF INFO chunk. Values are always ISO 8859-1 strings.

src/mpeg-ts/mpeg-ts-demuxer.ts

@@ -63,8 +63,6 @@ import { EncodedPacket, PacketType, PLACEHOLDER_DATA } from '../packet';
 import { FileSlice, readBytes, Reader, readU16Be, readU32Be, readU8 } from '../reader';
 import { buildMpegTsMimeType, MpegTsStreamType, TIMESCALE, TS_PACKET_SIZE } from './mpeg-ts-misc';
 
-const MISSING_PES_PACKET_ERROR = 'No PES packet found where one was expected.';
-
 type ElementaryStream = {
 	demuxer: MpegTsDemuxer;
 	pid: number;
@@ -191,6 +189,26 @@ export class MpegTsDemuxer extends Demuxer {
 				const BYTES_BEFORE_SECTION_LENGTH = 3;
 				const BITS_IN_CRC_32 = 32; // Duh
 
+				// Some streams don't contain a PAT for some reason, so we must do some guesswork to figure out where
+				// the PMT is.
+				let isProbablyProgramMap = false;
+				if (!hasProgramMap && section.pid !== 0) {
+					const isPesPacket
+						= section.payload[0] === 0x00 && section.payload[1] === 0x00 && section.payload[2] === 0x01;
+
+					if (!isPesPacket) {
+						// Assume it's a PSI
+
+						const bitstream = new Bitstream(section.payload);
+						const pointerField = bitstream.readAlignedByte();
+
+						bitstream.skipBits(8 * pointerField);
+
+						const tableId = bitstream.readBits(8);
+						isProbablyProgramMap = tableId === 0x02; // 0x02 == TS_program_map_section
+					}
+				}
+
 				if (section.pid === 0 && !hasProgramAssociationTable) {
 					const bitstream = new Bitstream(section.payload);
 					const pointerField = bitstream.readAlignedByte();
@@ -220,7 +238,7 @@ export class MpegTsDemuxer extends Demuxer {
 					}
 
 					hasProgramAssociationTable = true;
-				} else if (section.pid === programMapPid && !hasProgramMap) {
+				} else if ((section.pid === programMapPid || isProbablyProgramMap) && !hasProgramMap) {
 					const bitstream = new Bitstream(section.payload);
 					const pointerField = bitstream.readAlignedByte();
 
@@ -291,6 +309,7 @@ export class MpegTsDemuxer extends Demuxer {
 							default: {
 								// If we don't recognize the codec, we don't surface the track at all. This is because
 								// we can't determine its metadata and also have no idea how to packetize its data.
+								console.warn(`Unsupported stream_type 0x${streamType.toString(16)}; ignoring stream.`);
 							}
 						}
 
@@ -433,10 +452,11 @@ export class MpegTsDemuxer extends Demuxer {
 				currentPos += this.packetStride;
 			}
 
+			if (!hasProgramMap) {
 				if (!hasProgramAssociationTable) {
 					throw new Error('No Program Association Table found in the file.');
 				}
-			if (!hasProgramMap) {
+
 				throw new Error('No Program Map Table found in the file.');
 			}
 
@@ -674,6 +694,10 @@ type PesPacket = PesPacketHeader & {
 };
 
 const readPesPacketHeader = (section: Section): PesPacketHeader | null => {
+	if (section.payload.byteLength < 3) {
+		return null;
+	}
+
 	const bitstream = new Bitstream(section.payload);
 
 	const startCodePrefix = bitstream.readBits(24);
@@ -994,8 +1018,10 @@ export abstract class MpegTsTrackBacking implements InputTrackBacking {
 					}
 
 					const pesPacketHeader = readPesPacketHeader(section);
+					if (pesPacketHeader) {
 						return pesPacketHeader;
 					}
+				}
 
 				currentPos += demuxer.packetStride;
 			}
@@ -1152,9 +1178,7 @@ export abstract class MpegTsTrackBacking implements InputTrackBacking {
 						const section = await demuxer.readSection(currentPos, false);
 						if (section) {
 							const nextPesHeader = readPesPacketHeader(section);
-							if (!nextPesHeader) {
+							if (nextPesHeader) {
-								throw new Error(MISSING_PES_PACKET_ERROR);
-							}
 								if (nextPesHeader.pts > searchPts) {
 									break outer;
 								}
@@ -1165,6 +1189,7 @@ export abstract class MpegTsTrackBacking implements InputTrackBacking {
 								break;
 							}
 						}
+					}
 
 					currentPos += demuxer.packetStride;
 				}
@@ -1185,14 +1210,12 @@ export abstract class MpegTsTrackBacking implements InputTrackBacking {
 						const section = await demuxer.readSection(pos, false);
 						if (section) {
 							const header = readPesPacketHeader(section);
-							if (!header) {
+							if (header) {
-								throw new Error(MISSING_PES_PACKET_ERROR);
-							}
-
 								currentPesHeader = header;
 								break;
 							}
 						}
+					}
 
 					pos -= demuxer.packetStride;
 				}
@@ -1265,15 +1288,12 @@ export abstract class MpegTsTrackBacking implements InputTrackBacking {
 							const section = await demuxer.readSection(currentPos, false);
 							if (section) {
 								pesHeader = readPesPacketHeader(section);
-								if (!pesHeader) {
+								if (pesHeader) {
-									throw new Error(MISSING_PES_PACKET_ERROR);
-								}
-
 									maybeInsertReferencePacket(this.elementaryStream, pesHeader);
-
 									break;
 								}
 							}
+						}
 
 						currentPos += demuxer.packetStride;
 					}
@@ -1298,14 +1318,12 @@ export abstract class MpegTsTrackBacking implements InputTrackBacking {
 									const section = await demuxer.readSection(pos, false);
 									if (section) {
 										const header = readPesPacketHeader(section);
-										if (!header) {
+										if (header) {
-											throw new Error(MISSING_PES_PACKET_ERROR);
-										}
-
 											startPesHeader = header;
 											break;
 										}
 									}
+								}
 
 								pos -= demuxer.packetStride;
 							}
@@ -1759,23 +1777,20 @@ class PacketReadingContext {
 					}
 
 					if (packetHeader.pid === this.pid) {
-						break;
-					}
-
-					currentPos += this.demuxer.packetStride;
-				}
-
 						const nextSection = await this.demuxer.readSection(currentPos, true);
 						if (!nextSection) {
 							return;
 						}
 
 						const nextPesPacket = readPesPacket(nextSection);
-				if (!nextPesPacket) {
+						if (nextPesPacket) {
-					throw new Error(MISSING_PES_PACKET_ERROR);
+							pesPacket = nextPesPacket;
+							break;
+						}
 					}
 
-				pesPacket = nextPesPacket;
+					currentPos += this.demuxer.packetStride;
+				}
 			}
 
 			this.pesPackets.push(pesPacket);

test/node/metadata-tags.test.ts

@@ -1,6 +1,7 @@
 import { expect, test } from 'vitest';
 import { Output } from '../../src/output.js';
 import {
+	AdtsOutputFormat,
 	FlacOutputFormat,
 	MkvOutputFormat,
 	MovOutputFormat,
@@ -478,6 +479,61 @@ test('Read and write metadata, FLAC', async () => {
 	expect(readTags.raw!['COMPOSER']).toBe('Hans Zimmer');
 });
 
+test('Read and write metadata, ADTS', async () => {
+	const originalInput = new Input({
+		source: new FilePathSource(path.join(__dirname, '../public/sample3.aac')),
+		formats: ALL_FORMATS,
+	});
+
+	const output = new Output({
+		format: new AdtsOutputFormat(),
+		target: new BufferTarget(),
+	});
+
+	const conversion = await Conversion.init({
+		input: originalInput,
+		output,
+		tags: {
+			...songMetadata,
+			raw: {
+				TXXY: 'ID3v2 goated',
+			},
+		},
+	});
+	await conversion.execute();
+
+	using input = new Input({
+		source: new BufferSource(output.target.buffer!),
+		formats: ALL_FORMATS,
+	});
+
+	const readTags = await input.getMetadataTags();
+
+	// ID3v2 is goated, so pretty much everything was copied:
+	expect(readTags.title).toBe(songMetadata.title);
+	expect(readTags.description).toBe(songMetadata.description);
+	expect(readTags.artist).toBe(songMetadata.artist);
+	expect(readTags.album).toBe(songMetadata.album);
+	expect(readTags.albumArtist).toBe(songMetadata.albumArtist);
+	expect(readTags.comment).toBe(songMetadata.comment);
+	expect(readTags.lyrics).toBe(songMetadata.lyrics);
+	expect(readTags.trackNumber).toBe(songMetadata.trackNumber);
+	expect(readTags.tracksTotal).toBe(songMetadata.tracksTotal);
+	expect(readTags.discNumber).toBe(songMetadata.discNumber);
+	expect(readTags.discsTotal).toBe(songMetadata.discsTotal);
+	expect(readTags.date).toEqual(readTags.date);
+	expect(readTags.images).toHaveLength(1);
+	expect(readTags.images![0]!.data).toEqual(coverArt);
+	expect(readTags.images![0]!.mimeType).toEqual('image/jpeg');
+	expect(readTags.images![0]!.kind).toEqual('coverFront');
+	expect(readTags.images![0]!.description).toEqual(songMetadata.images![0]!.description);
+	expect(readTags.images![0]!.name).toBeUndefined(); // Can't be contained in ID3v2
+
+	expect(readTags.raw!['TIT2']).toBe(songMetadata.title);
+	expect(readTags.raw!['APIC']).instanceOf(Uint8Array);
+	expect(readTags.raw!['TXXY']).toBe('ID3v2 goated');
+});
+
 test('Read and write metadata, WAVE', async () => {
 	const output = new Output({
 		format: new WavOutputFormat(),