Allow object for tags field in conversion

dev/convert.html

@@ -47,23 +47,6 @@
 			format: outputFormat,
 			target
 		});
-		output.setMetadataTags({
-			title: 'Bigggy',
-			artist: 'Buck Bunny',
-			images: [{
-				data: blobData,
-				kind: 'coverFront',
-				mimeType: 'image/jpeg'
-			}],
-			trackNumber: 4,
-			tracksTotal: 10,
-			discNumber: 5,
-			discNumberMax: 8,
-			lyrics: "There's no way\nThat it's not going there",
-			raw: {
-				'ENCODER': 'Mediabunny epic own encoder'
-			}
-		});
 
 		const conversion = await Mediabunny.Conversion.init({
 			input: new Mediabunny.Input({
@@ -109,16 +92,16 @@
 			*/
 			video: () => ({
 				//discard: true,
-				crop: {
-					left: 0,
-					top: 0,
-					width: 500,
-					height: 500,
-				},
-				rotate: 90,
-				width: 200,
-				height: 500,
-				fit: 'contain',
+				//crop: {
+				//	left: 0,
+				//	top: 0,
+				//	width: 500,
+				//	height: 500,
+				//},
+				//rotate: 90,
+				//width: 200,
+				//height: 500,
+				//fit: 'contain',
 				//forceTranscode: true,
 				//codec: 'avc',
 				//fit: 'contain',
@@ -141,6 +124,23 @@
 				//width: 200,
 				//height: 100,
 			}),
+			tags: {
+				title: 'Bigggy',
+				artist: 'Buck Bunny',
+				images: [{
+					data: blobData,
+					kind: 'coverFront',
+					mimeType: 'image/jpeg'
+				}],
+				trackNumber: 4,
+				tracksTotal: 10,
+				discNumber: 5,
+				discsTotal: 8,
+				lyrics: "There's no way\nThat it's not going there",
+				raw: {
+					'AIGC': 'Mediabunny epic own encoder'
+				}
+			},
 			trim: {
 				start: 10,
 				end: 20

dev/demux.html

@@ -14,12 +14,7 @@
 			source: new Mediabunny.BlobSource(file),
 		});
 
-		const audioTrack = await input.getPrimaryAudioTrack();
-		const sink = new Mediabunny.EncodedPacketSink(audioTrack);
-
-		for await (const packet of sink.packets()) {
-			console.log(packet);
-		}
+		console.log(await input.getMetadataTags())
 
 		/*
 		const sink = new Mediabunny.EncodedPacketSink(videoTrack);

docs/guide/converting-media-files.md

@@ -49,7 +49,7 @@ await conversion.execute();
 That's it! A `Conversion` simply takes an instance of `Input` and `Output`, then reads the data from the input and writes it to the output. If you're unfamiliar with [`Input`](./reading-media-files) and [`Output`](./writing-media-files), check out their respective guides.
 
 ::: info
-The `Output` passed to the `Conversion` must be *fresh*; that is, it must have no added tracks and be in the `'pending'` state (not started yet).
+The `Output` passed to the `Conversion` must be *fresh*; that is, it must have no added tracks or metadata tags and be in the `'pending'` state (not started yet).
 :::
 
 Unconfigured, the conversion process handles all the details automatically, such as:
@@ -299,17 +299,17 @@ By default, any [descriptive metadata tags](../api/MetadataTags.md) of the input
 // Set your own metadata:
 const conversion = await Conversion.init({
 	// ...
-	tags: () => ({
+	tags: {
 		title: 're:Turning',
 		artist: 'Alexander Panos',
-	}),
+	},
 	// ...
 });
 
 // Or, augment the input's metadata:
 const conversion = await Conversion.init({
 	// ...
-	tags: inputTags => ({
+	tags: (inputTags) => ({
 		...inputTags, // Keep the existing metadata
 		images: [{ // And add cover art
 			data: new Uint8Array(...),
@@ -324,7 +324,7 @@ const conversion = await Conversion.init({
 // Or, remove all metadata
 const conversion = await Conversion.init({
 	// ...
-	tags: () => ({}),
+	tags: {},
 	// ...
 });
 ```

src/conversion.ts

@@ -89,13 +89,13 @@ export type ConversionOptions = {
 	};
 
 	/**
-	 * A callback that returns or resolves to the descriptive metadata tags that should be written to the output file.
-	 * As input, this function will be passed the tags of the input file, allowing you to modify, augment or extend
-	 * them.
+	 * An object or a callback that returns or resolves to an object containing the descriptive metadata tags that
+	 * should be written to the output file. If a function is passed, it will be passed the tags of the input file as
+	 * its first argument, allowing you to modify, augment or extend them.
 	 *
 	 * If no function is set, the input's metadata tags will be copied to the output.
 	 */
-	tags?: (inputTags: MetadataTags) => MaybePromise<MetadataTags>;
+	tags?: MetadataTags | ((inputTags: MetadataTags) => MaybePromise<MetadataTags>);
 };
 
 /**
@@ -395,8 +395,12 @@ export class Conversion {
 		if (!(options.output instanceof Output)) {
 			throw new TypeError('options.output must be an Output.');
 		}
-		if (options.output._tracks.length > 0 || options.output.state !== 'pending') {
-			throw new TypeError('options.output must be fresh: no tracks added and not started.');
+		if (
+			options.output._tracks.length > 0
+			|| Object.keys(options.output._metadataTags).length > 0
+			|| options.output.state !== 'pending'
+		) {
+			throw new TypeError('options.output must be fresh: no tracks or metadata tags added and not started.');
 		}
 
 		if (typeof options.video !== 'function') {
@@ -426,8 +430,15 @@ export class Conversion {
 			&& options.trim.start >= options.trim.end) {
 			throw new TypeError('options.trim.start must be less than options.trim.end.');
 		}
-		if (options.tags !== undefined && typeof options.tags !== 'function') {
-			throw new TypeError('options.tags, when provided, must be a function.');
+		if (
+			options.tags !== undefined
+			&& (typeof options.tags !== 'object' || !options.tags)
+			&& typeof options.tags !== 'function'
+		) {
+			throw new TypeError('options.tags, when provided, must be an object or a function.');
+		}
+		if (typeof options.tags === 'object') {
+			validateMetadataTags(options.tags);
 		}
 
 		this._options = options;
@@ -519,7 +530,9 @@ export class Conversion {
 		let outputTags: MetadataTags;
 
 		if (this._options.tags) {
-			const result = await this._options.tags(inputTags);
+			const result = typeof this._options.tags === 'function'
+				? await this._options.tags(inputTags)
+				: this._options.tags;
 			validateMetadataTags(result);
 
 			outputTags = result;