fix: fix mpg, mpeg, vob, and amv conversions

amv is weird as hell thanks for that (also i forgot that i could check vertd cause i already fixed them there lol)

src/lib/converters/ffmpeg/ffmpeg.svelte.ts

@@ -420,7 +420,105 @@ export class FFmpegConverter extends Converter {
 		let channelsArgs: string[] = [];
 		let tracksArgs: string[] = [];
 		let metadataArgs: string[] = [];
-		let m4aArgs: string[] = [];
+		const extraArgs: string[] = [];
+
+		const checkSettings = () => {
+			/*
+			 * sanity check settings for certain formats, to prevent conversion failure
+			 */
+			const settingsChanged: SettingChange[] = [];
+
+			console.log(
+				`checking settings for compatibility with output format ${to}...`,
+			);
+
+			if (to === ".opus") {
+				// work around browser stereo+libopus wasm crash
+				// no idea why its broken like this in the browser only lol
+				if (settings.channels >= 2) {
+					channelsArgs = ["-ac", "1"];
+					settingsChanged.push({
+						setting: "channels",
+						oldValue: settings.channels,
+						newValue: 1,
+						file: input.name,
+					});
+				}
+
+				// TODO: surely better way to do this as well :sob:
+				if (
+					audioBitrateArgs[1] &&
+					parseInt(audioBitrateArgs[1], 10) > 256
+				) {
+					audioBitrateArgs = ["-b:a", "256k"];
+					settingsChanged.push({
+						setting: "bitrate",
+						oldValue: settings.bitrate,
+						newValue: 256,
+						file: input.name,
+					});
+				}
+			} else if (to === ".amv") {
+				// amv requires mono audio, 32kbps, and 22050 sample rate
+				// block size is 22050 (sample rate) / fps. max is 8192, so we have to force a higher fps
+				const amvFps = 3;
+				const amvBlockSize = Math.floor(22050 / amvFps);
+
+				audioBitrateArgs = ["-b:a", "32k"];
+				sampleRateArgs = ["-ar", "22050"];
+				channelsArgs = ["-ac", "1"];
+				extraArgs.push(
+					"-r",
+					String(amvFps),
+					"-block_size",
+					String(amvBlockSize),
+				);
+				settingsChanged.push({
+					setting: "sampleRate",
+					oldValue: settings.sampleRate,
+					newValue: 22050,
+					file: input.name,
+				});
+				settingsChanged.push({
+					setting: "channels",
+					oldValue: settings.channels,
+					newValue: 1,
+					file: input.name,
+				});
+				settingsChanged.push({
+					setting: "bitrate",
+					oldValue: settings.bitrate,
+					newValue: 32,
+					file: input.name,
+				});
+			} else if (to === ".mpg" || to === ".mpeg" || to === ".vob") {
+				// these formats need to have its bitrate to the power of 2 to convert correctly
+				const bitrate = parseInt(audioBitrateArgs[1], 10);
+				const newBitrate = Math.pow(2, Math.round(Math.log2(bitrate)));
+				audioBitrateArgs = ["-b:a", `${newBitrate}k`];
+				settingsChanged.push({
+					setting: "bitrate",
+					oldValue: settings.bitrate,
+					newValue: newBitrate,
+					file: input.name,
+				});
+			}
+
+			for (const change of settingsChanged) {
+				this.log(
+					`changed setting "${change.setting}" from "${change.oldValue}" to "${change.newValue}" for file ${change.file} to prevent conversion failure`,
+				);
+				ToastManager.add({
+					type: "warning",
+					message: m["workers.warnings.settings_change"]({
+						setting: change.setting,
+						oldValue: change.oldValue,
+						newValue: change.newValue,
+						file: change.file,
+					}),
+				});
+			}
+		};
 
 		this.log(`keep metadata: ${keepMetadata}`);
 		if (!keepMetadata) {
@@ -522,6 +620,7 @@ export class FFmpegConverter extends Converter {
 		// video to audio
 		if (videoFormats.includes(inputFormat)) {
 			this.log(`Converting video ${input.from} to audio ${to}`);
+			checkSettings();
 			return [
 				"-i",
 				"input",
@@ -532,6 +631,7 @@ export class FFmpegConverter extends Converter {
 				...sampleRateArgs,
 				...channelsArgs,
 				...tracksArgs,
+				...extraArgs,
 				"output" + to,
 			];
 		}
@@ -545,6 +645,8 @@ export class FFmpegConverter extends Converter {
 				: false;
 			const codecArgs = toArgs(to, isAlac);
 
+			checkSettings();
+
 			if (hasAlbumArt) {
 				this.log("Using album art as video background");
 				return avWithArt(
@@ -554,6 +656,7 @@ export class FFmpegConverter extends Converter {
 					audioBitrateArgs,
 					sampleRateArgs,
 					channelsArgs,
+					extraArgs,
 				);
 			} else {
 				this.log("Using solid color background");
@@ -564,6 +667,7 @@ export class FFmpegConverter extends Converter {
 					audioBitrateArgs,
 					sampleRateArgs,
 					channelsArgs,
+					extraArgs,
 				);
 			}
 		}
@@ -571,60 +675,13 @@ export class FFmpegConverter extends Converter {
 		// audio to audio
 		this.log(`Converting audio ${input.from} to audio ${to}`);
 		const { audio: audioCodec } = getCodecs(to, isAlac);
-		if (m4a && keepMetadata) m4aArgs = ["-c:v", "copy"]; // for album art
+		if (m4a && keepMetadata) extraArgs.push("-c:v", "copy"); // for album art
 
-		/*
+		checkSettings();
-		 * sanity check settings for certain formats, to prevent conversion failure
-		 */
-		const settingsChanged: SettingChange[] = [];
-
-		if (to === ".opus") {
-			// work around browser stereo+libopus wasm crash
-			// no idea why its broken like this in the browser only lol
-			if (settings.channels >= 2) {
-				channelsArgs = ["-ac", "1"];
-				settingsChanged.push({
-					setting: "channels",
-					oldValue: settings.channels,
-					newValue: 1,
-					file: input.name,
-				});
-			}
-
-			// TODO: surely better way to do this as well :sob:
-			if (
-				audioBitrateArgs[1] &&
-				parseInt(audioBitrateArgs[1], 10) > 256
-			) {
-				audioBitrateArgs = ["-b:a", "256k"];
-				settingsChanged.push({
-					setting: "bitrate",
-					oldValue: settings.bitrate,
-					newValue: 256,
-					file: input.name,
-				});
-			}
-		}
-
-		for (const change of settingsChanged) {
-			this.log(
-				`changed setting "${change.setting}" from "${change.oldValue}" to "${change.newValue}" for file ${change.file} to prevent conversion failure`,
-			);
-			ToastManager.add({
-				type: "warning",
-				message: m["workers.warnings.settings_change"]({
-					setting: change.setting,
-					oldValue: change.oldValue,
-					newValue: change.newValue,
-					file: change.file,
-				}),
-			});
-		}
 
 		return [
 			"-i",
 			"input",
-			...m4aArgs,
 			"-c:a",
 			audioCodec,
 			...metadataArgs,
@@ -632,6 +689,7 @@ export class FFmpegConverter extends Converter {
 			...sampleRateArgs,
 			...channelsArgs,
 			...tracksArgs,
+			...extraArgs,
 			"-strict",
 			"experimental",
 			"output" + to,
@@ -724,7 +782,6 @@ const handleSpecialOutput = async (
 			".qoa",
 		);
 	}
-
 	// if (whatever other formats need special parsing)
 
 	return null;

src/lib/converters/ffmpeg/utils/ffmpeg.ts

@@ -56,6 +56,7 @@ export const avWithArt = (
 	audioBitrateArgs: string[],
 	sampleRateArgs: string[],
 	channelsArgs: string[],
+	extraArgs: string[],
 ): string[] => {
 	return [
 		"-loop",
@@ -80,6 +81,7 @@ export const avWithArt = (
 		...audioBitrateArgs,
 		...sampleRateArgs,
 		...channelsArgs,
+		...extraArgs,
 		"output" + to,
 	];
 };
@@ -92,6 +94,7 @@ export const avWithBg = (
 	audioBitrateArgs: string[],
 	sampleRateArgs: string[],
 	channelsArgs: string[],
+	extraArgs: string[],
 ): string[] => {
 	return [
 		"-f",
@@ -114,6 +117,7 @@ export const avWithBg = (
 		...audioBitrateArgs,
 		...sampleRateArgs,
 		...channelsArgs,
+		...extraArgs,
 		"output" + to,
 	];
 };

src/lib/converters/ffmpeg/utils/ffprobe.ts

@@ -44,7 +44,7 @@ export const detectAudioBitrate = async (
 
 	return await ffprobeValue(ffmpeg, args, (s) => {
 		const n = parseInt(s, 10);
-		return Number.isFinite(n) ? Math.round(n / 1000) : null;
+		return Number.isFinite(n) ? Math.floor(n / 1000) : null;
 	});
 };