Add support for reading and writing RF64 WAVE files

src/input-format.ts

@@ -291,7 +291,7 @@ export class WaveInputFormat extends InputFormat {
 
 		const riffReader = new RiffReader(input._mainReader);
 		const riffType = riffReader.readAscii(4);
-		if (riffType !== 'RIFF' && riffType !== 'RIFX') {
+		if (riffType !== 'RIFF' && riffType !== 'RIFX' && riffType !== 'RF64') {
 			return false;
 		}
 

src/output-format.ts

@@ -546,6 +546,12 @@ export class Mp3OutputFormat extends OutputFormat {
  * @public
  */
 export type WavOutputFormatOptions = {
+	/**
+	 * When enabled, an RF64 file be written, allowing for file sizes to exceed 4 GiB, which is otherwise not possible
+	 * for regular WAVE files.
+	 */
+	large?: boolean;
+
 	/**
 	 * Will be called once the file header is written. The header consists of the RIFF header, the format chunk, and the
 	 * start of the data chunk (with a placeholder size of 0).
@@ -565,6 +571,9 @@ export class WavOutputFormat extends OutputFormat {
 		if (!options || typeof options !== 'object') {
 			throw new TypeError('options must be an object.');
 		}
+		if (options.large !== undefined && typeof options.large !== 'boolean') {
+			throw new TypeError('options.large, when provided, must be a boolean.');
+		}
 		if (options.onHeader !== undefined && typeof options.onHeader !== 'function') {
 			throw new TypeError('options.onHeader, when provided, must be a function.');
 		}

src/wave/riff-reader.ts

@@ -35,6 +35,21 @@ export class RiffReader {
 		return view.getUint32(offset, this.littleEndian);
 	}
 
+	readU64() {
+		let low: number;
+		let high: number;
+
+		if (this.littleEndian) {
+			low = this.readU32();
+			high = this.readU32();
+		} else {
+			high = this.readU32();
+			low = this.readU32();
+		}
+
+		return high * 0x100000000 + low;
+	}
+
 	readAscii(length: number) {
 		const { view, offset } = this.reader.getViewAndOffset(this.pos, this.pos + length);
 		this.pos += length;

src/wave/riff-writer.ts

@@ -14,14 +14,20 @@ export class RiffWriter {
 
 	constructor(private writer: Writer) {}
 
+	writeU16(value: number) {
+		this.helperView.setUint16(0, value, true);
+		this.writer.write(this.helper.subarray(0, 2));
+	}
+
 	writeU32(value: number) {
 		this.helperView.setUint32(0, value, true);
 		this.writer.write(this.helper.subarray(0, 4));
 	}
 
-	writeU16(value: number) {
-		this.helperView.setUint16(0, value, true);
-		this.writer.write(this.helper.subarray(0, 2));
+	writeU64(value: number) {
+		this.helperView.setUint32(0, value, true);
+		this.helperView.setUint32(4, Math.floor(value / 2 ** 32), true);
+		this.writer.write(this.helper);
 	}
 
 	writeAscii(text: string) {

src/wave/wave-demuxer.ts

@@ -53,9 +53,13 @@ export class WaveDemuxer extends Demuxer {
 			const actualFileSize = await this.metadataReader.reader.source.getSize();
 
 			const riffType = this.metadataReader.readAscii(4);
-			this.metadataReader.littleEndian = riffType === 'RIFF';
+			this.metadataReader.littleEndian = riffType !== 'RIFX';
 
-			const totalFileSize = Math.min(this.metadataReader.readU32() + 8, actualFileSize);
+			const isRf64 = riffType === 'RF64';
+
+			const outerChunkSize = this.metadataReader.readU32();
+
+			let totalFileSize = isRf64 ? actualFileSize : Math.min(outerChunkSize + 8, actualFileSize);
 			const format = this.metadataReader.readAscii(4);
 
 			if (format !== 'WAVE') {
@@ -63,6 +67,9 @@ export class WaveDemuxer extends Demuxer {
 			}
 
 			this.metadataReader.pos = 12;
+			let chunksRead = 0;
+			let dataChunkSize: number | null = null;
+
 			while (this.metadataReader.pos < totalFileSize) {
 				await this.metadataReader.reader.loadRange(this.metadataReader.pos, this.metadataReader.pos + 8);
 
@@ -70,14 +77,28 @@ export class WaveDemuxer extends Demuxer {
 				const chunkSize = this.metadataReader.readU32();
 				const startPos = this.metadataReader.pos;
 
+				if (isRf64 && chunksRead === 0 && chunkId !== 'ds64') {
+					throw new Error('Invalid RF64 file: First chunk must be "ds64".');
+				}
+
 				if (chunkId === 'fmt ') {
 					await this.parseFmtChunk(chunkSize);
 				} else if (chunkId === 'data') {
+					dataChunkSize ??= chunkSize;
+
 					this.dataStart = this.metadataReader.pos;
-					this.dataSize = Math.min(chunkSize, totalFileSize - this.dataStart);
+					this.dataSize = Math.min(dataChunkSize, totalFileSize - this.dataStart);
+				} else if (chunkId === 'ds64') {
+					// File and data chunk sizes are defined in here instead
+
+					const riffChunkSize = this.metadataReader.readU64();
+					dataChunkSize = this.metadataReader.readU64();
+
+					totalFileSize = Math.min(riffChunkSize + 8, actualFileSize);
 				}
 
 				this.metadataReader.pos = startPos + chunkSize + (chunkSize & 1); // Handle padding
+				chunksRead++;
 			}
 
 			if (!this.audioInfo) {

src/wave/wave-muxer.ts

@@ -18,10 +18,13 @@ import { assert } from '../misc';
 
 export class WaveMuxer extends Muxer {
 	private format: WavOutputFormat;
+	private isRf64: boolean;
 	private writer: Writer;
 	private riffWriter: RiffWriter;
 	private headerWritten = false;
 	private dataSize = 0;
+	private sampleRate: number | null = null;
+	private sampleCount = 0;
 
 	constructor(output: Output, format: WavOutputFormat) {
 		super(output);
@@ -29,6 +32,7 @@ export class WaveMuxer extends Muxer {
 		this.format = format;
 		this.writer = output._writer;
 		this.riffWriter = new RiffWriter(output._writer);
+		this.isRf64 = !!format._options.large;
 	}
 
 	async start() {
@@ -58,13 +62,22 @@ export class WaveMuxer extends Muxer {
 				assert(meta.decoderConfig);
 
 				this.writeHeader(track, meta.decoderConfig);
+				this.sampleRate = meta.decoderConfig.sampleRate;
 				this.headerWritten = true;
 			}
 
 			this.validateAndNormalizeTimestamp(track, packet.timestamp, packet.type === 'key');
 
+			if (!this.isRf64 && this.writer.getPos() + packet.data.byteLength >= 2 ** 32) {
+				throw new Error(
+					'Adding more audio data would exceed the maximum RIFF size of 4 GiB. To write larger files, use'
+					+ ' RF64 by setting `large: true` in the WavOutputFormatOptions.',
+				);
+			}
+
 			this.writer.write(packet.data);
 			this.dataSize += packet.data.byteLength;
+			this.sampleCount += Math.round(packet.duration * this.sampleRate!);
 
 			await this.writer.flush();
 		} finally {
@@ -101,10 +114,26 @@ export class WaveMuxer extends Muxer {
 		const blockSize = pcmInfo.sampleSize * channels;
 
 		// RIFF header
-		this.riffWriter.writeAscii('RIFF');
-		this.riffWriter.writeU32(0); // File size placeholder
+		this.riffWriter.writeAscii(this.isRf64 ? 'RF64' : 'RIFF');
+
+		if (this.isRf64) {
+			this.riffWriter.writeU32(0xffffffff); // Not used in RF64
+		} else {
+			this.riffWriter.writeU32(0); // File size placeholder
+		}
+
 		this.riffWriter.writeAscii('WAVE');
 
+		if (this.isRf64) {
+			this.riffWriter.writeAscii('ds64');
+			this.riffWriter.writeU32(28); // Chunk size
+			this.riffWriter.writeU64(0); // RIFF size placeholder
+			this.riffWriter.writeU64(0); // Data size placeholder
+			this.riffWriter.writeU64(0); // Sample count placeholder
+			this.riffWriter.writeU32(0); // Table length
+			// Empty table
+		}
+
 		// fmt chunk
 		this.riffWriter.writeAscii('fmt ');
 		this.riffWriter.writeU32(16); // Chunk size
@@ -117,7 +146,12 @@ export class WaveMuxer extends Muxer {
 
 		// data chunk
 		this.riffWriter.writeAscii('data');
-		this.riffWriter.writeU32(0); // Data size placeholder
+
+		if (this.isRf64) {
+			this.riffWriter.writeU32(0xffffffff); // Not used in RF64
+		} else {
+			this.riffWriter.writeU32(0); // Data size placeholder
+		}
 
 		if (this.format._options.onHeader) {
 			const { data, start } = this.writer.stopTrackingWrites();
@@ -130,13 +164,27 @@ export class WaveMuxer extends Muxer {
 
 		const endPos = this.writer.getPos();
 
-		// Write file size
-		this.writer.seek(4);
-		this.riffWriter.writeU32(this.dataSize + 36); // File size - 8
+		if (this.isRf64) {
+			// Write riff size
+			this.writer.seek(20);
+			this.riffWriter.writeU64(endPos - 8);
 
-		// Write data chunk size
-		this.writer.seek(40);
-		this.riffWriter.writeU32(this.dataSize);
+			// Write data size
+			this.writer.seek(28);
+			this.riffWriter.writeU64(this.dataSize);
+
+			// Write sample count
+			this.writer.seek(36);
+			this.riffWriter.writeU64(this.sampleCount);
+		} else {
+			// Write file size
+			this.writer.seek(4);
+			this.riffWriter.writeU32(endPos - 8);
+
+			// Write data chunk size
+			this.writer.seek(40);
+			this.riffWriter.writeU32(this.dataSize);
+		}
 
 		this.writer.seek(endPos);