From 9c501808b17b7798e658287e0e67621ff89da3a8 Mon Sep 17 00:00:00 2001
From: Vanilagy <1696106+Vanilagy@users.noreply.github.com>
Date: Sun, 12 Jan 2025 16:52:28 +0100
Subject: [PATCH] Add WebMInputFormat, add OutputFormat.getFileExtension()

---
 dev/index.html       |  2 +-
 src/index.ts         |  3 ++-
 src/input-format.ts  | 31 ++++++++++++++++++++++++++-----
 src/output-format.ts | 21 +++++++++++++++++++++
 4 files changed, 50 insertions(+), 7 deletions(-)

diff --git a/dev/index.html b/dev/index.html
index 92ad378..ad720d0 100644
--- a/dev/index.html
+++ b/dev/index.html
@@ -174,5 +174,5 @@ Testing... <00:17.350>One... <00:18.125>Two...
 	await output.finalize();
 
 	console.log(target);
-	download(new Blob([target.buffer]), 'test.webm');
+	download(new Blob([target.buffer]), 'test' + format.getFileExtension());
 </script>
\ No newline at end of file
diff --git a/src/index.ts b/src/index.ts
index 8f4c15a..0813fe7 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -52,8 +52,9 @@ export {
 	InputFormat,
 	IsobmffInputFormat,
 	Mp4InputFormat,
-	QuickTimeInputFormat as MovInputFormat,
+	QuickTimeInputFormat,
 	MatroskaInputFormat,
+	WebMInputFormat,
 	WaveInputFormat,
 	ALL_FORMATS,
 	MP4,
diff --git a/src/input-format.ts b/src/input-format.ts
index d730a7d..5125ae2 100644
--- a/src/input-format.ts
+++ b/src/input-format.ts
@@ -81,7 +81,7 @@ export class QuickTimeInputFormat extends IsobmffInputFormat {
 /** @public */
 export class MatroskaInputFormat extends InputFormat {
 	/** @internal */
-	async _canReadInput(input: Input) {
+	protected async isSupportedEBMLOfDocType(input: Input, desiredDocType: string) {
 		const sourceSize = await input._mainReader.source._getSize();
 		if (sourceSize < 8) {
 			return false;
@@ -89,7 +89,7 @@ export class MatroskaInputFormat extends InputFormat {
 
 		const ebmlReader = new EBMLReader(input._mainReader);
 		const varIntSize = ebmlReader.readVarIntSize();
-		if (varIntSize < 1 || varIntSize > 6) {
+		if (varIntSize < 1 || varIntSize > 8) {
 			return false;
 		}
 
@@ -124,7 +124,7 @@ export class MatroskaInputFormat extends InputFormat {
 				}; break;
 				case EBMLId.DocType: {
 					const docType = ebmlReader.readString(size);
-					if (docType !== 'matroska' && docType !== 'webm') {
+					if (docType !== desiredDocType) {
 						return false;
 					}
 				}; break;
@@ -142,6 +142,11 @@ export class MatroskaInputFormat extends InputFormat {
 		return true;
 	}
 
+	/** @internal */
+	_canReadInput(input: Input) {
+		return this.isSupportedEBMLOfDocType(input, 'matroska');
+	}
+
 	/** @internal */
 	_createDemuxer(input: Input) {
 		return new MatroskaDemuxer(input);
@@ -156,6 +161,22 @@ export class MatroskaInputFormat extends InputFormat {
 	}
 }
 
+/** @public */
+export class WebMInputFormat extends MatroskaInputFormat {
+	/** @internal */
+	override _canReadInput(input: Input) {
+		return this.isSupportedEBMLOfDocType(input, 'webm');
+	}
+
+	override getName() {
+		return 'WebM';
+	}
+
+	override getMimeType() {
+		return 'video/webm';
+	}
+}
+
 /** @public */
 export class WaveInputFormat extends InputFormat {
 	async _canReadInput(input: Input) {
@@ -196,9 +217,9 @@ export const QTFF = new QuickTimeInputFormat();
 /** @public */
 export const MATROSKA = new MatroskaInputFormat();
 /** @public */
-export const WEBM = MATROSKA;
+export const WEBM = new WebMInputFormat();
 /** @public */
 export const WAVE = new WaveInputFormat();
 
 /** @public */
-export const ALL_FORMATS: InputFormat[] = [MP4, QTFF, MATROSKA, WAVE];
+export const ALL_FORMATS: InputFormat[] = [MP4, QTFF, MATROSKA, WEBM, WAVE];
diff --git a/src/output-format.ts b/src/output-format.ts
index 63e3ab7..bbed1f4 100644
--- a/src/output-format.ts
+++ b/src/output-format.ts
@@ -12,6 +12,7 @@ export abstract class OutputFormat {
 
 	/** @internal */
 	abstract _getName(): string;
+	abstract getFileExtension(): string;
 	abstract getSupportedCodecs(): MediaCodec[];
 
 	getSupportedVideoCodecs() {
@@ -69,6 +70,10 @@ export class Mp4OutputFormat extends IsobmffOutputFormat {
 		return 'MP4';
 	}
 
+	getFileExtension() {
+		return '.mp4';
+	}
+
 	getSupportedCodecs() {
 		return Mp4OutputFormat.getSupportedCodecs();
 	}
@@ -98,6 +103,10 @@ export class MovOutputFormat extends IsobmffOutputFormat {
 		return 'MOV';
 	}
 
+	getFileExtension() {
+		return '.mov';
+	}
+
 	getSupportedCodecs() {
 		return MovOutputFormat.getSupportedCodecs();
 	}
@@ -152,6 +161,10 @@ export class MkvOutputFormat extends OutputFormat {
 		return 'Matroska';
 	}
 
+	getFileExtension() {
+		return '.mkv';
+	}
+
 	getSupportedCodecs() {
 		return MkvOutputFormat.getSupportedCodecs();
 	}
@@ -181,6 +194,10 @@ export class WebMOutputFormat extends MkvOutputFormat {
 		return 'WebM';
 	}
 
+	override getFileExtension() {
+		return '.webm';
+	}
+
 	static override getSupportedCodecs(): MediaCodec[] {
 		return [
 			'vp8', 'vp9', 'av1',
@@ -211,6 +228,10 @@ export class WaveOutputFormat extends OutputFormat {
 		return 'WAVE';
 	}
 
+	getFileExtension() {
+		return '.wav';
+	}
+
 	getSupportedCodecs() {
 		return WaveOutputFormat.getSupportedCodecs();
 	}