1

scripts/nodejs/subtitle_bgm_generate.js

@@ -6,7 +6,7 @@
 const fs = require("fs");
 const path = require("path");
 const os = require("os");
-const { spawnSync } = require("child_process");
+const { spawn, spawnSync } = require("child_process");
 
 const pipelineNative = require("./pipeline_native.js");
 const desktopConfig = require("./desktop_config.js");
@@ -31,14 +31,69 @@ function makeOutputPath(prefix, ext = "mp4") {
   return path.join(ensureDir(), `${prefix}_${Date.now()}.${ext}`);
 }
 
-function execFfmpeg(args) {
+const FFMPEG_TIMEOUT_MS = 15 * 60 * 1000;
+
+function tailFfmpegLog(text, maxLines = 24) {
+  const lines = String(text || "")
+    .split(/\r?\n/)
+    .map((l) => l.trim())
+    .filter(Boolean);
+  if (lines.length <= maxLines) return lines.join("\n");
+  return lines.slice(-maxLines).join("\n");
+}
+
+/**
+ * 异步执行 ffmpeg（避免 spawnSync 默认 1MB maxBuffer 在重编码时撑爆）
+ * @param {string[]} args
+ * @param {string} [label]
+ */
+function execFfmpeg(args, label = "ffmpeg") {
   const ffmpeg = pipelineNative.locateFfmpeg();
   if (!ffmpeg) {
     throw new Error("未找到 ffmpeg，请配置 AICLIENT_FFMPEG_PATH 或 src-tauri/binaries/ffmpeg.exe");
   }
-  const r = spawnSync(ffmpeg, args, { encoding: "utf8", windowsHide: true });
-  if (r.status !== 0) {
-    throw new Error((r.stderr || r.stdout || "").trim() || `ffmpeg 退出码 ${r.status}`);
+  const fullArgs = ["-hide_banner", "-loglevel", "warning", "-nostats", ...args];
+  logSubtitle("info", `${label} 开始`, { args: fullArgs.slice(0, 12) });
+
+  return new Promise((resolve, reject) => {
+    const child = spawn(ffmpeg, fullArgs, { windowsHide: true });
+    let stderr = "";
+    child.stderr.on("data", (chunk) => {
+      stderr = (stderr + chunk.toString()).slice(-256 * 1024);
+    });
+    const timer = setTimeout(() => {
+      child.kill("SIGKILL");
+      reject(new Error(`${label} 超时（超过 15 分钟），请缩短视频或降低分辨率后重试`));
+    }, FFMPEG_TIMEOUT_MS);
+    child.on("error", (err) => {
+      clearTimeout(timer);
+      reject(err);
+    });
+    child.on("close", (code) => {
+      clearTimeout(timer);
+      if (code === 0) {
+        resolve();
+        return;
+      }
+      const tail = tailFfmpegLog(stderr);
+      reject(
+        new Error(
+          tail
+            ? `${label} 失败（退出码 ${code}）：\n${tail}`
+            : `${label} 失败，退出码 ${code}`,
+        ),
+      );
+    });
+  });
+}
+
+function assertOutputVideo(outputPath, label) {
+  if (!outputPath || !fs.existsSync(outputPath)) {
+    throw new Error(`${label} 未生成输出文件`);
+  }
+  const stat = fs.statSync(outputPath);
+  if (stat.size < 1024) {
+    throw new Error(`${label} 输出文件过小（${stat.size} 字节），可能已损坏`);
   }
 }
 
@@ -494,25 +549,83 @@ function formatAssTime(ms) {
   return `${h}:${String(m).padStart(2, "0")}:${String(s).padStart(2, "0")}.${String(cs).padStart(2, "0")}`;
 }
 
+const VIDEO_ENCODE_ARGS = [
+  "-c:v",
+  "libx264",
+  "-preset",
+  "fast",
+  "-crf",
+  "23",
+  "-pix_fmt",
+  "yuv420p",
+  "-movflags",
+  "+faststart",
+];
+
 /**
- * @param {string} [keywordDrawtextFilter] 逗号分隔的 drawtext 滤镜（关键词高亮）
+ * 先烧录 ASS，再单独叠加关键词 drawtext（避免超长 -vf 与滤镜逗号冲突）
+ * @param {string} [keywordDrawtextFilter]
  */
-function addSubtitleToVideo(inputVideo, subtitlePath, keywordDrawtextFilter) {
-  const outputVideo = makeOutputPath("with_subtitle");
+async function addSubtitleToVideo(inputVideo, subtitlePath, keywordDrawtextFilter) {
+  const withSubtitle = makeOutputPath("with_subtitle");
   const sub = escapeSubPath(subtitlePath);
-  let vf = `subtitles='${sub}'`;
-  if (keywordDrawtextFilter) {
-    vf = `${vf},${keywordDrawtextFilter}`;
-  }
-  execFfmpeg(["-y", "-i", inputVideo, "-vf", vf, "-c:a", "copy", outputVideo]);
-  return outputVideo;
+  await execFfmpeg(
+    [
+      "-y",
+      "-i",
+      inputVideo,
+      "-vf",
+      `subtitles='${sub}'`,
+      ...VIDEO_ENCODE_ARGS,
+      "-c:a",
+      "copy",
+      withSubtitle,
+    ],
+    "烧录字幕",
+  );
+  assertOutputVideo(withSubtitle, "烧录字幕");
+
+  if (!keywordDrawtextFilter) {
+    return withSubtitle;
   }
 
-function addBgmToVideo(inputVideo, bgmPath, bgmVolume = 30) {
+  const withKeyword = makeOutputPath("with_keyword");
+  try {
+    await execFfmpeg(
+      [
+        "-y",
+        "-i",
+        withSubtitle,
+        "-vf",
+        keywordDrawtextFilter,
+        ...VIDEO_ENCODE_ARGS,
+        "-c:a",
+        "copy",
+        withKeyword,
+      ],
+      "关键词特效",
+    );
+    assertOutputVideo(withKeyword, "关键词特效");
+    try {
+      fs.unlinkSync(withSubtitle);
+    } catch {
+      /* ignore */
+    }
+    return withKeyword;
+  } catch (err) {
+    logSubtitle("warn", "关键词 drawtext 失败，已保留无特效字幕版", {
+      error: err instanceof Error ? err.message : String(err),
+    });
+    return withSubtitle;
+  }
+}
+
+async function addBgmToVideo(inputVideo, bgmPath, bgmVolume = 30) {
   const outputVideo = makeOutputPath("with_bgm");
   const ratio = Number(bgmVolume) / 100;
   const filter = `[0:a]volume=1.0[a0];[1:a]volume=${ratio}[a1];[a0][a1]amix=inputs=2:duration=first`;
-  execFfmpeg([
+  await execFfmpeg(
+    [
       "-y",
       "-i",
       inputVideo,
@@ -526,7 +639,10 @@ function addBgmToVideo(inputVideo, bgmPath, bgmVolume = 30) {
       "copy",
       "-shortest",
       outputVideo,
-  ]);
+    ],
+    "混合 BGM",
+  );
+  assertOutputVideo(outputVideo, "混合 BGM");
   return outputVideo;
 }
 
@@ -697,13 +813,13 @@ globalThis.__nodejsMain = async function main(params) {
           ? "正在烧录字幕并叠加关键词特效…"
           : "正在烧录字幕到视频…",
       );
-      current = addSubtitleToVideo(current, assPath, keywordDrawtextFilter);
+      current = await addSubtitleToVideo(current, assPath, keywordDrawtextFilter);
       pipelineNative.deleteFile(audioPath);
     }
 
     if (bgmEnabled) {
       globalThis.__native?.emitProgress?.("正在混合背景音乐…");
-      current = addBgmToVideo(current, p.bgmPath, p.bgmVolume ?? 30);
+      current = await addBgmToVideo(current, p.bgmPath, p.bgmVolume ?? 30);
     }
 
     return {

scripts/nodejs/subtitle_keyword_drawtext.js

@@ -278,11 +278,12 @@ function buildDrawtextForMatch(match, layout) {
 
   const t0 = match.startSec.toFixed(3);
   const t1 = match.endSec.toFixed(3);
-  const enable = `between(t\\,${t0}\\,${t1})`;
+  /** 用 gte*lte 避免 between(t,a,b) 中逗号打断 -vf 滤镜链 */
+  const enable = `gte(t\\,${t0})*lte(t\\,${t1})`;
 
   let fontsizePart = String(baseSize);
   if (match.effectType === "pulse-scale") {
-    fontsizePart = `${baseSize}*(1+0.1*sin(2*PI*(t-${t0})*4))`;
+    fontsizePart = `${baseSize}*(1+0.08*sin(8*PI*t))`;
   }
 
   const parts = [
@@ -323,7 +324,19 @@ function buildKeywordDrawtextFilter(matches, opts) {
     position: String(style.position || "bottom"),
   };
 
-  return matches.map((m) => buildDrawtextForMatch(m, layout)).join(",");
+  const filters = matches.map((m) => buildDrawtextForMatch(m, layout));
+  const chain = filters.join(",");
+  if (chain.length > 6000) {
+    logKeywordWarn("drawtext 滤镜过长，仅保留前 40 个关键词");
+    return filters.slice(0, 40).join(",");
+  }
+  return chain;
+}
+
+function logKeywordWarn(msg, fields) {
+  if (globalThis.__native?.log) {
+    globalThis.__native.log("warn", `[autoGenerateSubtitleAndBGM] ${msg}`, fields ?? null);
+  }
 }
 
 /**