Merge branch 'fleet/story-d1-webm-remux'

src/lib/server/pipeline.ts

@@ -90,6 +90,9 @@ async function runJob(
 		} else {
 			rawAudioPath = await saveUploadedFile(input.buffer, input.filename, jobId);
 			title = input.filename.replace(/\.[^.]+$/, '');
+			// Remux webm files (MediaRecorder output) to fix Cues/duration
+			const { remuxUpload } = await import('./remux.js');
+			rawAudioPath = await remuxUpload(rawAudioPath, jobId);
 		}
 
 		updateJob({ id: jobId, title });

src/lib/server/remux.ts

@@ -0,0 +1,69 @@
+import { execFile } from 'child_process';
+import { unlink, rename, mkdir } from 'fs/promises';
+import { join, extname } from 'path';
+import { existsSync } from 'fs';
+
+const REMUX_DIR = join(process.env.DATA_DIR ?? '/tmp/.whisper-pwa', 'remux');
+
+async function ensureTmpDir() {
+	if (!existsSync(REMUX_DIR)) await mkdir(REMUX_DIR, { recursive: true });
+}
+
+/** Wrap execFile in a promise without using util.promisify */
+function execFileAsync(cmd: string, args: string[]): Promise<{ stdout: string; stderr: string }> {
+	return new Promise((resolve, reject) => {
+		execFile(cmd, args, (err, stdout, stderr) => {
+			if (err) reject(err);
+			else resolve({ stdout, stderr });
+		});
+	});
+}
+
+/**
+ * Remux an uploaded webm file to fix Cues/duration metadata.
+ *
+ * Browser MediaRecorder produces opus-in-webm output without finalized
+ * Cues (seeking index) and with unset/streaming duration. Downstream
+ * ffmpeg audio-prep (prepareAudio) fails on such files with "duration
+ * unknown" or corrupt-container errors.
+ *
+ * This function uses ffmpeg stream copy (no re-encode) to rewrite
+ * container headers, generating proper Cues and finalizing duration.
+ * Non-webm files pass through unchanged.
+ *
+ * @param inputPath - Path to the uploaded file
+ * @param jobId     - Job ID for temp file naming
+ * @returns The (possibly remuxed) path — same as inputPath if remuxed in-place
+ */
+export async function remuxUpload(inputPath: string, jobId: string): Promise<string> {
+	const ext = extname(inputPath).toLowerCase();
+
+	// Only remux webm files — other formats pass through
+	if (ext !== '.webm') {
+		return inputPath;
+	}
+
+	await ensureTmpDir();
+	const tmpPath = join(REMUX_DIR, `${jobId}.webm`);
+
+	try {
+		await execFileAsync('ffmpeg', [
+			'-y',
+			'-i', inputPath,
+			'-c', 'copy',
+			'-fflags', '+genpts',
+			'-f', 'webm',
+			tmpPath
+		]);
+
+		// Replace original with remuxed file
+		await unlink(inputPath);
+		await rename(tmpPath, inputPath);
+
+		return inputPath;
+	} catch (err) {
+		// Clean up temp file on failure
+		await unlink(tmpPath).catch(() => {});
+		throw err;
+	}
+}