Initial commit: PodcastYes — AI podcast platform

lib/ai/ffmpeg.ts

@@ -0,0 +1,45 @@
+import { spawn } from "node:child_process";
+
+const FFMPEG = process.env.FFMPEG_PATH ?? "ffmpeg";
+const FFPROBE = process.env.FFPROBE_PATH ?? "ffprobe";
+
+/** Run ffmpeg with the given args; rejects with the tail of stderr on non-zero exit. */
+export function runFfmpeg(args: string[]): Promise<void> {
+  return new Promise((resolve, reject) => {
+    const proc = spawn(FFMPEG, args, { stdio: ["ignore", "ignore", "pipe"] });
+    let stderr = "";
+    proc.stderr.on("data", (d) => {
+      stderr += d.toString();
+    });
+    proc.on("error", (err) =>
+      reject(new Error(`Failed to spawn ffmpeg (${FFMPEG}): ${err.message}`))
+    );
+    proc.on("close", (code) =>
+      code === 0 ? resolve() : reject(new Error(`ffmpeg exited ${code}: ${stderr.slice(-600)}`))
+    );
+  });
+}
+
+/** Probe an audio file's duration in whole seconds, or null if ffprobe is unavailable. */
+export function ffprobeDuration(file: string): Promise<number | null> {
+  return new Promise((resolve) => {
+    const proc = spawn(FFPROBE, [
+      "-v",
+      "error",
+      "-show_entries",
+      "format=duration",
+      "-of",
+      "default=noprint_wrappers=1:nokey=1",
+      file,
+    ]);
+    let out = "";
+    proc.stdout.on("data", (d) => {
+      out += d.toString();
+    });
+    proc.on("error", () => resolve(null));
+    proc.on("close", () => {
+      const n = parseFloat(out.trim());
+      resolve(Number.isFinite(n) ? Math.round(n) : null);
+    });
+  });
+}