111

scripts/nodejs/subtitle_bgm_generate.js

@@ -10,6 +10,15 @@ const { spawnSync } = require("child_process");
 
 const pipelineNative = require("./pipeline_native.js");
 const desktopConfig = require("./desktop_config.js");
+const { correctTextWithLevenshtein, similarity: textSimilarity } = require("./subtitle_levenshtein.js");
+const {
+  buildKeywordGroups,
+  matchKeywordsInRecords,
+  buildKeywordDrawtextFilter,
+  normalizeDisplayText,
+  stripKeywordsFromDisplay,
+  filterMatchesForRecord,
+} = require("./subtitle_keyword_drawtext.js");
 
 const OUTPUT_DIR = path.join(os.tmpdir(), "aiclient-subtitle-bgm");
 
@@ -123,20 +132,63 @@ function normalizeAsrTimeToMs(value) {
   return Math.round(n * 1000);
 }
 
-function normalizeAsrRecords(records) {
-  if (!Array.isArray(records)) return [];
-  const normalized = records
+/** 对齐 ZimuShengcheng.shouldTreatTimelineAsSeconds */
+function shouldTreatTimelineAsSeconds(records) {
+  const valid = records.filter(
+    (r) => Number.isFinite(Number(r?.start)) && Number.isFinite(Number(r?.end)),
+  );
+  if (valid.length === 0) return false;
+  const maxEnd = Math.max(...valid.map((r) => Number(r.end)));
+  const maxDur = Math.max(...valid.map((r) => Number(r.end) - Number(r.start)));
+  return maxEnd <= 600 && maxDur <= 30;
+}
+
+function normalizeFunasrSegmentsToMilliseconds(records) {
+  if (!Array.isArray(records) || records.length === 0) return [];
+  const mapped = records
     .map((record) => {
       const text = String(record?.text || record?.sentence || "").trim();
       if (!text) return null;
-      let start = normalizeAsrTimeToMs(
-        record.start ?? record.begin ?? record.beginTime ?? 0,
-      );
-      let end = normalizeAsrTimeToMs(
-        record.end ?? record.endTime ?? start + 2000,
-      );
+      return {
+        text,
+        start: Number(record.start ?? record.begin ?? record.beginTime ?? 0),
+        end: Number(record.end ?? record.endTime ?? 0),
+        words: record.words,
+      };
+    })
+    .filter(Boolean);
+
+  if (shouldTreatTimelineAsSeconds(mapped)) {
+    logSubtitle("info", "检测到秒级时间轴，统一转换为毫秒");
+    return mapped.map((r) => ({
+      ...r,
+      start: Math.round(r.start * 1000),
+      end: Math.round((r.end > r.start ? r.end : r.start + 2) * 1000),
+      words: Array.isArray(r.words)
+        ? r.words.map((w) => ({
+            ...w,
+            start: Math.round(Number(w.start ?? w.begin_time ?? 0) * 1000),
+            end: Math.round(Number(w.end ?? w.end_time ?? 0) * 1000),
+          }))
+        : r.words,
+    }));
+  }
+
+  return mapped.map((r) => {
+    let start = normalizeAsrTimeToMs(r.start);
+    let end = normalizeAsrTimeToMs(r.end || start + 2);
+    if (end <= start) end = start + 2000;
+    return { text: r.text, start, end, words: r.words };
+  });
+}
+
+function normalizeAsrRecords(records) {
+  if (!Array.isArray(records)) return [];
+  const normalized = normalizeFunasrSegmentsToMilliseconds(records)
+    .map((record) => {
+      let { start, end } = record;
       if (end <= start) end = start + 2000;
-      return { text, start, end };
+      return { text: record.text, start, end, words: record.words };
     })
     .filter(Boolean);
   const MIN_GAP_MS = 50;
@@ -194,6 +246,36 @@ function cleanSubtitleDisplayText(text) {
     .trim();
 }
 
+/**
+ * 智能字幕：Levenshtein 校对（ZimuShengcheng），失败时回退按句均分
+ */
+function applySmartSubtitle(script, records, videoDurationSec = 0) {
+  const normalized = normalizeAsrRecords(records);
+  const scriptTrim = String(script || "").trim();
+  if (!scriptTrim) return normalized;
+
+  const asrPlain = normalized.map((r) => r.text).join("");
+  const sim = textSimilarity(
+    scriptTrim.replace(/\s+/g, ""),
+    asrPlain.replace(/\s+/g, ""),
+  );
+
+  if (normalized.length > 0 && sim >= 0.25) {
+    const { segments, similarity } = correctTextWithLevenshtein(scriptTrim, normalized);
+    if (segments.length > 0) {
+      logSubtitle("info", "Levenshtein 文案校对", {
+        count: segments.length,
+        similarity: Math.round(similarity * 1000) / 1000,
+        scriptSimilarity: Math.round(sim * 1000) / 1000,
+      });
+      return segments;
+    }
+  }
+
+  logSubtitle("info", "Levenshtein 未产出有效段落，回退按句对齐", { similarity: sim });
+  return alignScriptToRecords(scriptTrim, normalized, videoDurationSec);
+}
+
 function alignScriptToRecords(script, records, videoDurationSec = 0) {
   const lines = splitScriptLines(script);
   const normalized = normalizeAsrRecords(records);
@@ -337,7 +419,7 @@ function resolveAssLayout(position, videoHeight) {
   return { alignment: 2, marginL: 120, marginR: 120, marginV };
 }
 
-function buildAssContent(records, styleInput, videoWidth, videoHeight) {
+function buildAssContent(records, styleInput, videoWidth, videoHeight, keywordMatches = []) {
   const style = normalizeBurnStyle(styleInput);
   const width = Math.max(320, Number(videoWidth) || 1920);
   const height = Math.max(320, Number(videoHeight) || 1080);
@@ -349,13 +431,26 @@ function buildAssContent(records, styleInput, videoWidth, videoHeight) {
     height,
   );
   const hasBg = style.hasBg;
-  const borderStyle = hasBg ? 3 : 1;
-  const finalOutline = hasBg ? 1 : outline;
-  const backColour = hasBg
-    ? hexToAssColor(style.backgroundColor)
-    : "&H00000000";
+  let borderStyle = 1;
+  let finalOutline = outline;
+  let finalShadow = 0;
+  let backColour = "&H00000000";
   const primary = hexToAssColor(style.fontColor);
-  const outlineColour = hexToAssColor(style.outlineColor);
+  let outlineColour = hexToAssColor(style.outlineColor);
+
+  if (hasBg) {
+    borderStyle = 3;
+    finalOutline = 1;
+    finalShadow = 0;
+    backColour = hexToAssColor(style.backgroundColor);
+    outlineColour = backColour;
+  } else {
+    borderStyle = 1;
+    finalOutline = outline || 3;
+    finalShadow = 0;
+    backColour = "&H00000000";
+    outlineColour = hexToAssColor(style.outlineColor);
+  }
 
   const header = [
     "[Script Info]",
@@ -368,7 +463,7 @@ function buildAssContent(records, styleInput, videoWidth, videoHeight) {
     "",
     "[V4+ Styles]",
     "Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, OutlineColour, BackColour, Bold, Italic, Underline, StrikeOut, ScaleX, ScaleY, Spacing, Angle, BorderStyle, Outline, Shadow, Alignment, MarginL, MarginR, MarginV, Encoding",
-    `Style: Default,${style.fontName},${fontSize},${primary},${primary},${outlineColour},${backColour},0,0,0,0,100,100,0,0,${borderStyle},${finalOutline},0,${alignment},${marginL},${marginR},${marginV},1`,
+    `Style: Default,${style.fontName},${fontSize},${primary},&H000000FF,${outlineColour},${backColour},1,0,0,0,100,100,0,0,${borderStyle},${finalOutline},${finalShadow},${alignment},${marginL},${marginR},${marginV},1`,
     "",
     "[Events]",
     "Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text",
@@ -377,8 +472,14 @@ function buildAssContent(records, styleInput, videoWidth, videoHeight) {
   const events = records.map((r) => {
     const start = formatAssTime(r.start);
     const end = formatAssTime(Math.max(r.end, r.start + 500));
-    const text = assEscapeText(wrapSubtitleText(r.text, style.maxCharsPerLine));
-    if (!text) return "";
+    const display = normalizeDisplayText(r.text);
+    const segMatches = filterMatchesForRecord(r, keywordMatches);
+    const baseDisplay =
+      segMatches.length > 0
+        ? stripKeywordsFromDisplay(display, segMatches)
+        : display;
+    const text = assEscapeText(wrapSubtitleText(baseDisplay || " ", style.maxCharsPerLine));
+    if (!text.replace(/\\N/g, "").trim()) return "";
     return `Dialogue: 0,${start},${end},Default,,0,0,0,,${text}`;
   }).filter(Boolean);
 
@@ -393,10 +494,16 @@ function formatAssTime(ms) {
   return `${h}:${String(m).padStart(2, "0")}:${String(s).padStart(2, "0")}.${String(cs).padStart(2, "0")}`;
 }
 
-function addSubtitleToVideo(inputVideo, subtitlePath, styleInput) {
+/**
+ * @param {string} [keywordDrawtextFilter] 逗号分隔的 drawtext 滤镜（关键词高亮）
+ */
+function addSubtitleToVideo(inputVideo, subtitlePath, keywordDrawtextFilter) {
   const outputVideo = makeOutputPath("with_subtitle");
   const sub = escapeSubPath(subtitlePath);
-  const vf = `subtitles='${sub}'`;
+  let vf = `subtitles='${sub}'`;
+  if (keywordDrawtextFilter) {
+    vf = `${vf},${keywordDrawtextFilter}`;
+  }
   execFfmpeg(["-y", "-i", inputVideo, "-vf", vf, "-c:a", "copy", outputVideo]);
   return outputVideo;
 }
@@ -521,7 +628,7 @@ globalThis.__nodejsMain = async function main(params) {
             : 0,
       });
       if (p.smartSubtitle !== false && scriptContent) {
-        records = alignScriptToRecords(scriptContent, records, videoDuration);
+        records = applySmartSubtitle(scriptContent, records, videoDuration);
         logSubtitle("info", "智能字幕对齐后", { count: records.length });
       }
       if (!records.length) {
@@ -553,15 +660,44 @@ globalThis.__nodejsMain = async function main(params) {
       }
 
       const { width, height } = probeVideoSize(current);
+
+      let keywordDrawtextFilter = null;
+      let keywordMatches = [];
+      const enableKeywords = p.enableKeywordEffects !== false;
+      const keywordGroups = buildKeywordGroups(p);
+      if (enableKeywords && keywordGroups.length > 0) {
+        keywordMatches = matchKeywordsInRecords(records, keywordGroups);
+        logSubtitle("info", "关键词匹配", {
+          groups: keywordGroups.length,
+          matches: keywordMatches.length,
+          keywords: keywordMatches.slice(0, 8).map((m) => m.keyword),
+        });
+        if (keywordMatches.length > 0) {
+          keywordDrawtextFilter = buildKeywordDrawtextFilter(keywordMatches, {
+            videoWidth: width,
+            videoHeight: height,
+            subtitleStyle: burnStyle,
+          });
+          if (!keywordDrawtextFilter) {
+            logSubtitle("warn", "未找到可用字体，跳过关键词 drawtext 特效");
+            keywordMatches = [];
+          }
+        }
+      }
+
       const assPath = makeOutputPath("subtitle", "ass");
       fs.writeFileSync(
         assPath,
-        buildAssContent(records, burnStyle, width, height),
+        buildAssContent(records, burnStyle, width, height, keywordMatches),
         "utf8",
       );
 
-      globalThis.__native?.emitProgress?.("正在烧录字幕到视频…");
-      current = addSubtitleToVideo(current, assPath, burnStyle);
+      globalThis.__native?.emitProgress?.(
+        keywordDrawtextFilter
+          ? "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);
       pipelineNative.deleteFile(audioPath);
     }
 

scripts/nodejs/subtitle_keyword_drawtext.js

@@ -0,0 +1,363 @@
+"use strict";
+
+/**
+ * 关键词高亮 drawtext（对齐 Electron ZimuShengcheng inline 模式 + pulse-scale）
+ */
+
+const fs = require("fs");
+const path = require("path");
+const os = require("os");
+
+const PUNCT_RE =
+  /[，。！？；：、""''（）《》【】…—·,.!?;:'"()[\]{}<>]/g;
+
+const DEFAULT_GROUP_META = {
+  focus: {
+    name: "重点词",
+    effectId: "pulse-scale",
+    styleConfig: {
+      fontColor: "#FFD700",
+      outlineColor: "#FF8C00",
+      outlineWidth: 4,
+    },
+  },
+  describe: {
+    name: "描述词",
+    effectId: "pulse-scale",
+    styleConfig: {
+      fontColor: "#5AC8FA",
+      outlineColor: "#007AFF",
+      outlineWidth: 3,
+    },
+  },
+  action: {
+    name: "行动词",
+    effectId: "pulse-scale",
+    styleConfig: {
+      fontColor: "#34C759",
+      outlineColor: "#248A3D",
+      outlineWidth: 3,
+    },
+  },
+  emotion: {
+    name: "情感词",
+    effectId: "pulse-scale",
+    styleConfig: {
+      fontColor: "#FF6B6B",
+      outlineColor: "#C92A2A",
+      outlineWidth: 3,
+    },
+  },
+};
+
+function parseKeywordLines(text) {
+  return String(text || "")
+    .split(/[\n,，、]+/)
+    .map((s) => s.trim())
+    .filter(Boolean);
+}
+
+/**
+ * 从步骤 04 字段或显式 keywordGroups 构建分组
+ * @param {Record<string, unknown>} params
+ */
+function buildKeywordGroups(params) {
+  if (Array.isArray(params.keywordGroups) && params.keywordGroups.length > 0) {
+    return params.keywordGroups
+      .map((g) => normalizeKeywordGroup(g))
+      .filter((g) => g.keywords.length > 0);
+  }
+
+  const sources = [
+    ["focus", params.keywordsFocus],
+    ["describe", params.keywordsDescribe],
+    ["action", params.keywordsAction],
+    ["emotion", params.keywordsEmotion],
+  ];
+
+  return sources
+    .map(([id, raw]) => {
+      const meta = DEFAULT_GROUP_META[id] || DEFAULT_GROUP_META.focus;
+      const keywords = parseKeywordLines(raw);
+      if (!keywords.length) return null;
+      return {
+        id,
+        name: meta.name,
+        effectId: meta.effectId,
+        styleConfig: { ...meta.styleConfig },
+        keywords,
+      };
+    })
+    .filter(Boolean);
+}
+
+function normalizeKeywordGroup(group) {
+  const g = group && typeof group === "object" ? group : {};
+  const keywords = (Array.isArray(g.keywords) ? g.keywords : [])
+    .map((k) => (typeof k === "string" ? k : String(k?.keyword || "")).trim())
+    .filter(Boolean);
+  return {
+    id: String(g.id || g.groupId || "group"),
+    name: String(g.name || g.groupName || "关键词"),
+    effectId: String(g.effectId || g.effectConfig?.type || "pulse-scale"),
+    styleConfig: g.styleConfig || g.styleOverride || {},
+    keywords,
+  };
+}
+
+function normalizeDisplayText(text) {
+  return String(text || "")
+    .replace(PUNCT_RE, "")
+    .replace(/\s+/g, "");
+}
+
+function normalizeEffectType(effectId) {
+  const id = String(effectId || "pulse-scale").toLowerCase();
+  if (id.includes("pulse") || id.includes("scale")) return "pulse-scale";
+  if (id.includes("slide")) return "slide";
+  return "highlight";
+}
+
+function buildKeywordStyle(group, keywordItem) {
+  const base = group.styleConfig || {};
+  const override =
+    keywordItem && typeof keywordItem === "object" ? keywordItem.styleOverride : null;
+  const o = override || base;
+  return {
+    fontColor: o.fontColor || "#FFD700",
+    outlineColor: o.outlineColor || "#FF8C00",
+    outlineWidth: Number(o.outlineWidth) ?? 4,
+    fontSize: Number(o.fontSize) || 0,
+  };
+}
+
+/**
+ * @param {Array<{ text: string, start: number, end: number }>} records 毫秒
+ * @param {ReturnType<typeof buildKeywordGroups>} groups
+ */
+function matchKeywordsInRecords(records, groups) {
+  const matches = [];
+  const seen = new Set();
+
+  for (const record of records) {
+    const display = normalizeDisplayText(record.text);
+    if (!display) continue;
+
+    const segStartSec = record.start / 1000;
+    const segEndSec = record.end / 1000;
+    const dur = Math.max(0.05, segEndSec - segStartSec);
+
+    for (const group of groups) {
+      for (const kw of group.keywords) {
+        const raw = typeof kw === "string" ? kw : String(kw?.keyword || "");
+        const needle = normalizeDisplayText(raw);
+        if (!needle) continue;
+
+        let searchFrom = 0;
+        while (searchFrom < display.length) {
+          const idx = display.indexOf(needle, searchFrom);
+          if (idx === -1) break;
+
+          const dedupeKey = `${segStartSec.toFixed(3)}-${segEndSec.toFixed(3)}-${needle}-${idx}`;
+          if (!seen.has(dedupeKey)) {
+            seen.add(dedupeKey);
+            const ratioStart = idx / display.length;
+            const ratioEnd = (idx + needle.length) / display.length;
+            const startSec = segStartSec + dur * ratioStart;
+            const endSec = Math.max(startSec + 0.08, segStartSec + dur * ratioEnd);
+
+            matches.push({
+              keyword: needle,
+              text: needle,
+              lineText: display,
+              lineLength: display.length,
+              occurrenceStart: idx,
+              occurrenceEnd: idx + needle.length,
+              startSec,
+              endSec,
+              groupId: group.id,
+              groupName: group.name,
+              effectType: normalizeEffectType(
+                (typeof kw === "object" && kw?.effectId) || group.effectId,
+              ),
+              style: buildKeywordStyle(group, kw),
+            });
+          }
+          searchFrom = idx + Math.max(1, needle.length);
+        }
+      }
+    }
+  }
+
+  return matches.sort((a, b) => a.startSec - b.startSec);
+}
+
+const WIN_FONT_MAP = {
+  "microsoft yahei": ["msyh.ttc", "msyhbd.ttc"],
+  "microsoft yahei bold": ["msyhbd.ttc", "msyh.ttc"],
+  simhei: ["simhei.ttf"],
+  "sim sun": ["simsun.ttc"],
+  "source han sans": ["SourceHanSansSC-Regular.otf"],
+};
+
+function resolveFontFile(fontName) {
+  const fromEnv = process.env.AICLIENT_SUBTITLE_FONT_PATH;
+  if (fromEnv && fs.existsSync(fromEnv)) return fromEnv;
+
+  const key = String(fontName || "Microsoft YaHei")
+    .trim()
+    .toLowerCase();
+  const candidates = WIN_FONT_MAP[key] || WIN_FONT_MAP["microsoft yahei"];
+
+  if (process.platform === "win32") {
+    const fontsDir = path.join(process.env.WINDIR || "C:\\Windows", "Fonts");
+    for (const file of candidates) {
+      const full = path.join(fontsDir, file);
+      if (fs.existsSync(full)) return full;
+    }
+  }
+
+  const fallbacks = [
+    "/usr/share/fonts/truetype/noto/NotoSansCJK-Regular.ttc",
+    "/System/Library/Fonts/PingFang.ttc",
+    "/System/Library/Fonts/Supplemental/Arial Unicode.ttf",
+  ];
+  for (const p of fallbacks) {
+    if (fs.existsSync(p)) return p;
+  }
+  return null;
+}
+
+function escapeDrawtextPath(filePath) {
+  return filePath
+    .replace(/\\/g, "/")
+    .replace(/:/g, "\\:")
+    .replace(/'/g, "\\'");
+}
+
+function escapeDrawtextText(text) {
+  return String(text || "")
+    .replace(/\\/g, "\\\\")
+    .replace(/'/g, "\\'")
+    .replace(/:/g, "\\:")
+    .replace(/,/g, "\\,");
+}
+
+function hexToDrawtextColor(hex) {
+  const h = String(hex || "#FFFFFF").replace("#", "").slice(0, 6);
+  if (h.length !== 6) return "white";
+  return `0x${h.toUpperCase()}`;
+}
+
+function resolveSubtitleY(position, videoHeight) {
+  const h = Math.max(360, Number(videoHeight) || 1080);
+  if (position === "top") return "h*0.12";
+  if (position === "center") return "(h-text_h)/2";
+  return "h*0.82-text_h";
+}
+
+/**
+ * @param {ReturnType<typeof matchKeywordsInRecords>[number]} match
+ * @param {{ videoWidth: number, videoHeight: number, baseFontSize: number, fontfile: string, position: string }} layout
+ */
+function buildDrawtextForMatch(match, layout) {
+  const { videoWidth, videoHeight, baseFontSize, fontfile, position } = layout;
+  const style = match.style || {};
+  const baseSize = style.fontSize > 0 ? style.fontSize : Math.round(baseFontSize * 1.45);
+  const outlineW = Math.max(1, Math.round(style.outlineWidth || 3));
+  const fontColor = hexToDrawtextColor(style.fontColor);
+  const borderColor = hexToDrawtextColor(style.outlineColor);
+
+  const lineLen = Math.max(1, match.lineLength);
+  const charWidth = baseSize * 0.55;
+  const lineWidth = Math.min(lineLen * charWidth, videoWidth * 0.88);
+  const keywordMid = (match.occurrenceStart + match.occurrenceEnd) / 2;
+  const offsetPx = (keywordMid / lineLen) * lineWidth - lineWidth / 2;
+  const xExpr = `(w-text_w)/2+${offsetPx.toFixed(1)}`;
+  const yExpr = resolveSubtitleY(position, videoHeight);
+
+  const t0 = match.startSec.toFixed(3);
+  const t1 = match.endSec.toFixed(3);
+  const enable = `between(t\\,${t0}\\,${t1})`;
+
+  let fontsizePart = String(baseSize);
+  if (match.effectType === "pulse-scale") {
+    fontsizePart = `${baseSize}*(1+0.1*sin(2*PI*(t-${t0})*4))`;
+  }
+
+  const parts = [
+    `fontfile='${escapeDrawtextPath(fontfile)}'`,
+    `text='${escapeDrawtextText(match.text)}'`,
+    `fontsize='${fontsizePart}'`,
+    `fontcolor=${fontColor}`,
+    `borderw=${outlineW}`,
+    `bordercolor=${borderColor}`,
+    `x='${xExpr}'`,
+    `y='${yExpr}'`,
+    `enable='${enable}'`,
+  ];
+  return `drawtext=${parts.join(":")}`;
+}
+
+/**
+ * @param {ReturnType<typeof matchKeywordsInRecords>} matches
+ * @param {{ videoWidth: number, videoHeight: number, subtitleStyle?: Record<string, unknown> }} opts
+ * @returns {string | null} ffmpeg -vf 链（逗号分隔的 drawtext）
+ */
+function buildKeywordDrawtextFilter(matches, opts) {
+  if (!matches.length) return null;
+
+  const videoWidth = Math.max(320, Number(opts.videoWidth) || 1920);
+  const videoHeight = Math.max(320, Number(opts.videoHeight) || 1080);
+  const style = opts.subtitleStyle || {};
+  const scale = Math.max(0.2, Math.min(2, (Number(style.fontSizeScale) || 100) / 100));
+  const baseFontSize = Math.max(14, Math.round((Number(style.fontSize) || 35) * scale));
+  const fontfile = resolveFontFile(style.fontName);
+  if (!fontfile) return null;
+
+  const layout = {
+    videoWidth,
+    videoHeight,
+    baseFontSize,
+    fontfile,
+    position: String(style.position || "bottom"),
+  };
+
+  return matches.map((m) => buildDrawtextForMatch(m, layout)).join(",");
+}
+
+/**
+ * 从 ASS 底字中移除关键词字符，避免与 drawtext 高亮重复
+ * @param {string} displayText 已去标点文本
+ * @param {Array<{ occurrenceStart: number, occurrenceEnd: number }>} matches
+ */
+function stripKeywordsFromDisplay(displayText, matches) {
+  const text = String(displayText || "");
+  if (!text || !matches.length) return text;
+  const chars = [...text];
+  for (const m of matches) {
+    const start = Math.max(0, m.occurrenceStart);
+    const end = Math.min(chars.length, m.occurrenceEnd);
+    for (let i = start; i < end; i++) chars[i] = "";
+  }
+  return chars.join("").trim();
+}
+
+/** @param {{ start: number, end: number }} record 毫秒 */
+function filterMatchesForRecord(record, matches) {
+  const segStart = record.start / 1000;
+  const segEnd = record.end / 1000;
+  return matches.filter(
+    (m) => m.startSec >= segStart - 0.02 && m.endSec <= segEnd + 0.02,
+  );
+}
+
+module.exports = {
+  buildKeywordGroups,
+  matchKeywordsInRecords,
+  buildKeywordDrawtextFilter,
+  normalizeDisplayText,
+  stripKeywordsFromDisplay,
+  filterMatchesForRecord,
+  resolveFontFile,
+};

scripts/nodejs/subtitle_levenshtein.js

@@ -0,0 +1,265 @@
+"use strict";
+
+/**
+ * 文案与 ASR 时间轴对齐（对齐 Electron ZimuShengcheng / Levenshtein）
+ */
+
+const PUNCTUATION_RE =
+  /[，。！？、；：\u201C\u201D"「」『』（）【】《》,.!?;:'"]/;
+
+const DEFAULT_CHAR_DURATION_MS = 150;
+const TIME_GAP_SPLIT_THRESHOLD_MS = 500;
+
+function levenshteinDistance(a, b) {
+  const n = a.length;
+  const m = b.length;
+  const dp = Array.from({ length: n + 1 }, () => Array(m + 1).fill(0));
+  for (let i = 0; i <= n; i++) dp[i][0] = i;
+  for (let j = 0; j <= m; j++) dp[0][j] = j;
+  for (let i = 1; i <= n; i++) {
+    for (let j = 1; j <= m; j++) {
+      const cost = a[i - 1] === b[j - 1] ? 0 : 1;
+      dp[i][j] = Math.min(dp[i - 1][j] + 1, dp[i][j - 1] + 1, dp[i - 1][j - 1] + cost);
+    }
+  }
+  return dp[n][m];
+}
+
+function findBestMatch(userText, asrText) {
+  const n = userText.length;
+  const m = asrText.length;
+  const dp = Array.from({ length: n + 1 }, () => Array(m + 1).fill(0));
+  const bt = Array.from({ length: n + 1 }, () => Array(m + 1).fill(""));
+  for (let i = 0; i <= n; i++) {
+    dp[i][0] = i;
+    bt[i][0] = "delete";
+  }
+  for (let j = 0; j <= m; j++) {
+    dp[0][j] = j;
+    bt[0][j] = "insert";
+  }
+  for (let i = 1; i <= n; i++) {
+    for (let j = 1; j <= m; j++) {
+      const cost = userText[i - 1] === asrText[j - 1] ? 0 : 1;
+      const del = dp[i - 1][j] + 1;
+      const ins = dp[i][j - 1] + 1;
+      const sub = dp[i - 1][j - 1] + cost;
+      const best = Math.min(del, ins, sub);
+      dp[i][j] = best;
+      if (best === del) bt[i][j] = "delete";
+      else if (best === ins) bt[i][j] = "insert";
+      else if (cost === 0) bt[i][j] = "match";
+      else bt[i][j] = "replace";
+    }
+  }
+  const alignments = [];
+  let i = n;
+  let j = m;
+  while (i > 0 || j > 0) {
+    const op = bt[i][j];
+    if (op === "match") {
+      alignments.unshift({
+        userChar: userText[i - 1],
+        asrChar: asrText[j - 1],
+        operation: "match",
+        asrIndex: j - 1,
+      });
+      i -= 1;
+      j -= 1;
+    } else if (op === "replace") {
+      alignments.unshift({
+        userChar: userText[i - 1],
+        asrChar: asrText[j - 1],
+        operation: "replace",
+        asrIndex: j - 1,
+      });
+      i -= 1;
+      j -= 1;
+    } else if (op === "delete") {
+      alignments.unshift({
+        userChar: userText[i - 1],
+        asrChar: "",
+        operation: "delete",
+        asrIndex: j,
+      });
+      i -= 1;
+    } else {
+      alignments.unshift({
+        userChar: "",
+        asrChar: asrText[j - 1],
+        operation: "insert",
+        asrIndex: j - 1,
+      });
+      j -= 1;
+    }
+  }
+  const distance = dp[n][m];
+  const similarity = 1 - distance / Math.max(n, m, 1);
+  return { alignments, distance, similarity };
+}
+
+function buildSegmentCharTimings(segment) {
+  const text = segment.text || "";
+  const len = text.length;
+  if (len === 0) return [];
+  const step = (segment.end - segment.start) / Math.max(len, 1);
+  const fallback = Array.from({ length: len }, (_, idx) => ({
+    start: segment.start + idx * step,
+    end: segment.start + (idx + 1) * step,
+  }));
+  const words = Array.isArray(segment.words) ? segment.words : [];
+  if (words.length === 0) return fallback;
+
+  const mapped = Array(len).fill(null);
+  let searchFrom = 0;
+  for (const w of words) {
+    const word = String(w?.word ?? w?.text ?? "");
+    const start = Number(w?.start ?? w?.beginTime ?? w?.begin_time);
+    const end = Number(w?.end ?? w?.endTime ?? w?.end_time);
+    if (!word || !Number.isFinite(start) || !Number.isFinite(end) || end <= start) continue;
+    const pos = text.indexOf(word, searchFrom);
+    if (pos === -1) continue;
+    const wordStep = (end - start) / Math.max(word.length, 1);
+    for (let k = 0; k < word.length && pos + k < len; k++) {
+      mapped[pos + k] = { start: start + k * wordStep, end: start + (k + 1) * wordStep };
+    }
+    searchFrom = pos + word.length;
+  }
+  return mapped.map((item, idx) => item || fallback[idx]);
+}
+
+function buildCharTimeMap(segments) {
+  const map = new Map();
+  let index = 0;
+  for (const segment of segments) {
+    for (const timing of buildSegmentCharTimings(segment)) {
+      map.set(index, timing);
+      index += 1;
+    }
+  }
+  return map;
+}
+
+function mapToTimestamps(alignments, charMap) {
+  const segments = [];
+  let text = "";
+  let start = 0;
+  let end = 0;
+  let corrected = false;
+  let isFirstChar = true;
+
+  for (let y = 0; y < alignments.length; y++) {
+    const row = alignments[y];
+    const timing =
+      row.asrIndex != null && row.asrIndex >= 0 ? charMap.get(row.asrIndex) : null;
+    const isPunct = row.userChar && PUNCTUATION_RE.test(row.userChar);
+
+    if (row.operation === "match" || row.operation === "replace") {
+      if (!isPunct) text += row.userChar;
+      if (row.operation === "replace") corrected = true;
+      if (timing) {
+        if (isFirstChar) {
+          start = timing.start;
+          isFirstChar = false;
+        }
+        end = timing.end;
+      }
+    } else if (row.operation === "insert") {
+      if (timing) {
+        if (isFirstChar) {
+          start = timing.start;
+          isFirstChar = false;
+        }
+        end = timing.end;
+      }
+    } else if (row.operation === "delete") {
+      if (!isPunct) {
+        text += row.userChar;
+        const t = isFirstChar ? start : end;
+        if (isFirstChar) {
+          start = t;
+          isFirstChar = false;
+        }
+        if (!timing) end = t + DEFAULT_CHAR_DURATION_MS;
+      }
+      corrected = true;
+    }
+
+    const isLast = y === alignments.length - 1;
+    const nextRow = alignments[y + 1];
+    const nextTiming =
+      nextRow && nextRow.asrIndex != null && nextRow.asrIndex >= 0
+        ? charMap.get(nextRow.asrIndex)
+        : null;
+    const gapSplit =
+      !isLast && timing && nextTiming && nextTiming.start - end > TIME_GAP_SPLIT_THRESHOLD_MS;
+
+    if ((isLast || isPunct || gapSplit) && text.length > 0) {
+      if (end <= start) end = start + text.length * DEFAULT_CHAR_DURATION_MS;
+      segments.push({
+        text,
+        start,
+        end,
+        corrected,
+      });
+      start = end;
+      text = "";
+      corrected = false;
+      isFirstChar = true;
+    }
+  }
+
+  if (text.length > 0) {
+    if (end <= start) end = start + text.length * DEFAULT_CHAR_DURATION_MS;
+    segments.push({ text, start, end, corrected });
+  }
+  return segments;
+}
+
+/**
+ * @param {string} userText
+ * @param {Array<{ text: string, start: number, end: number, words?: unknown[] }>} asrSegments
+ */
+function correctTextWithLevenshtein(userText, asrSegments) {
+  const user = String(userText || "").replace(/\s+/g, "");
+  const list = Array.isArray(asrSegments) ? asrSegments : [];
+  if (!user || list.length === 0) {
+    return { segments: [], similarity: 0 };
+  }
+
+  const asrFullText = list.map((s) => s.text || "").join("");
+  const match = findBestMatch(user, asrFullText);
+  const charMap = buildCharTimeMap(list);
+  const corrected = mapToTimestamps(match.alignments, charMap);
+
+  const MIN_GAP_MS = 50;
+  const out = corrected
+    .map((seg) => ({
+      text: String(seg.text || "").trim(),
+      start: Math.round(seg.start),
+      end: Math.round(seg.end),
+    }))
+    .filter((seg) => seg.text);
+
+  for (let i = 0; i < out.length - 1; i++) {
+    const cur = out[i];
+    const next = out[i + 1];
+    if (cur.end >= next.start) {
+      cur.end = Math.max(cur.start + MIN_GAP_MS, next.start - MIN_GAP_MS);
+    }
+    if (cur.end <= cur.start) cur.end = cur.start + MIN_GAP_MS;
+  }
+
+  return { segments: out, similarity: match.similarity };
+}
+
+function similarity(a, b) {
+  const max = Math.max(a.length, b.length);
+  if (max === 0) return 1;
+  return 1 - levenshteinDistance(a, b) / max;
+}
+
+module.exports = {
+  correctTextWithLevenshtein,
+  similarity,
+};