Feat/improve performance (#6)

* chore: append '/' if missing, to avoid read file error

* doc: handle if no npx available

* feat: improve performance

* chore: separate subtitle-merge

* chore: bump version

Author: helloint

README.md

@@ -11,7 +11,9 @@
 1. 进入视频所在目录
 2. 命令行执行：`npx dual-subtitle`
 
-字幕文件会以`.chs-eng.srt`结尾
+注：有些环境（比如群晖）如果没有npx，可以试试用`npm exec dual-subtitle`代替。
+
+生成的字幕文件会以`.chs-eng.srt`结尾。
 
 ## 介绍
 此工具主要是为了满足在Infuse上看流媒体视频时，能够显示双语字幕的需求。Infuse本身并不支持同时显示2条不同语言的字幕。

analyzeMedia.js

@@ -1,13 +1,35 @@
+import { execSync } from 'child_process';
 import ffprobe from "ffprobe";
-import ffprobeStatic from "ffprobe-static";
+import ffprobeInstaller from '@ffprobe-installer/ffprobe';
 import {config} from "./config.js";
 
+const getFFprobePath = () => {
+    try {
+        // 检查系统是否安装了 ffprobe
+        execSync('ffprobe -version', { stdio: 'ignore' });
+        // 如果能执行到这里，说明系统已安装
+        console.log('使用本地ffprobe');
+        return 'ffprobe'; // 返回系统命令
+    } catch (e) {
+        return ffprobeInstaller.path;
+    }
+}
+
 export const analyzeMedia = (file) => {
+    console.log(`获取字幕信息...`);
+    const ffprobePath = getFFprobePath();
     return new Promise((resolve, reject) => {
-        ffprobe(config.workdir + file, { path: ffprobeStatic.path })
+        ffprobe(config.workdir + file, { path: ffprobePath })
             .then(function (info) {
                 // console.log(info);
-                resolve(info);
+                const subTitles = info.streams.filter((stream) => stream.codec_type === 'subtitle').map(stream => ({
+                    index: stream.index,
+                    code: stream.tags.language.toLowerCase(),
+                    name: stream.tags.title ? stream.tags.title.toLowerCase() : '',
+                    duration: Math.round(stream.duration),
+                }));
+                console.log(`找到 ${subTitles.length} 条字幕。`);
+                resolve(subTitles);
             })
             .catch(function (err) {
                 // console.error(err);

config.js

@@ -5,7 +5,7 @@ const config = {
 };
 
 if (process.argv.length > 2) {
-    config.workdir = process.argv[2];
+    config.workdir = process.argv[2].endsWith('/') ? process.argv[2] : process.argv[2] + '/';
 }
 
 export { config };

extractSub.js

@@ -3,24 +3,48 @@ import ffmpeg from 'fluent-ffmpeg';
 import {config} from "./config.js";
 import {removeExtension} from "./utils.js";
 
-ffmpeg.setFfmpegPath(ffmpegInstaller.path);
+const getFFmpegPath = () => {
+    try {
+        // 检查系统是否安装了 ffprobe
+        execSync('ffmpeg -version', { stdio: 'ignore' });
+        // 如果能执行到这里，说明系统已安装
+        console.log('使用本地ffmpeg');
+        return 'ffmpeg'; // 返回系统命令
+    } catch (e) {
+        return ffmpegInstaller.path;
+    }
+}
 
-export const extractSub = (filename, subIdx) => {
+/**
+ * "timemark":"00:06:52.07"
+ * @param timemark
+ * @returns {number}
+ */
+const timemarkToSeconds = (timemark) => {
+    const [hms, ms] = timemark.split('.');
+    const [h, m, s] = hms.split(':');
+    return (+h * 3600) + (+m * 60) + (+s) + (+ms / 100);
+}
+
+export const extractSub = (filename, targetSubs) => {
     return new Promise((resolve, reject) => {
         const mainSrt = `${removeExtension(filename)}.chs.srt`;
         const secondarySrt = `${removeExtension(filename)}.eng.srt`;
+        const duration = targetSubs[0].duration;
 
+        ffmpeg.setFfmpegPath(getFFmpegPath());
         ffmpeg(config.workdir + filename)
             .output(config.workdir + mainSrt)
-            .outputOptions(['-map', `0:${subIdx[0]}`, '-c', 'copy'])
+            .outputOptions(['-map', `0:${targetSubs[0].index}`, '-c', 'copy'])
             .output(config.workdir + secondarySrt)
-            .outputOptions(['-map', `0:${subIdx[1]}`, '-c', 'copy'])
+            .outputOptions(['-map', `0:${targetSubs[1].index}`, '-c', 'copy'])
             .run()
             .on('start', function (str) {
                 console.log('转换任务开始～', str);
             })
             .on('progress', function (progress) {
-                console.log(`进行中，完成${(progress.percent || 0)}%`);
+                const progressPercent = Math.round((timemarkToSeconds(progress.timemark) / duration) * 100);
+                console.log(`进行中，完成${(progressPercent || 0)}%`);
             })
             .on('end', function (str) {
                 console.log('转换任务完成！');

findIndex.js

@@ -0,0 +1,84 @@
+export const findSub = (subTitles) => {
+    console.log('查找简体和英语字幕...');
+    const chsSub = findChiSub(subTitles);
+    const engSub = findEngSub(subTitles);
+
+    if (chsSub === null || engSub === null) {
+        if (chsSub === null) {
+            console.log('没有找到简体中文字幕');
+        }
+
+        if (engSub === null) {
+            console.log('没有找到英语字幕');
+        }
+
+        throw new Error('字幕查找失败，中断执行');
+    }
+
+    console.log('找到简体中文字幕，索引为：', chsSub.index);
+    console.log('找到英语字幕，索引为：', engSub.index);
+    console.log('时长：', chsSub.duration);
+
+    return [chsSub, engSub];
+}
+
+/**
+ * 目前看到的数据可能有：
+ * chi,简体
+ * chi,Simplified Chinese
+ * 查找策略是：先找 'chi', 如果数量大于1，则进一步找 "简体"
+ */
+const findChiSub = (subTitles) => {
+    const chineseSubtitles = subTitles.filter(subTitle => subTitle.code === 'chi');
+
+    if (chineseSubtitles.length === 0) {
+        return null;
+    }
+
+    if (chineseSubtitles.length === 1) {
+        return {
+            index: chineseSubtitles[0].index,
+            duration: chineseSubtitles[0].duration
+        };
+    }
+
+    // If multiple Chinese subtitles, look for Simplified Chinese
+    const targetSub = chineseSubtitles.find(subTitle =>
+        subTitle.name.includes('简体') ||
+        subTitle.name.includes('simplified')
+    );
+
+    return targetSub ? {
+        index: targetSub.index,
+        duration: targetSub.duration
+    } : null;
+}
+
+/**
+ * 目前看到的数据可能有：
+ * 9,subrip,eng
+ * 10,subrip,eng,SDH
+ * 23,subrip,eng,English[CC]
+ * 如果同时有SDH和非SDH版本，选非SDH版本。
+ */
+const findEngSub = (subTitles) => {
+    const englishSubs = subTitles.filter(sub => sub.code === 'eng');
+
+    if (englishSubs.length === 0) return null;
+    if (englishSubs.length === 1) return {
+        index: englishSubs[0].index,
+        duration: englishSubs[0].duration,
+    };
+
+    // Filter out SDH subtitles if there are multiple English options
+    const nonSDHSubs = englishSubs.filter(sub =>
+        !sub.name.includes('sdh')
+    );
+
+    // Return first non-SDH sub if available, otherwise first English sub
+    const targetSub = nonSDHSubs[0] || englishSubs[0];
+    return targetSub ? {
+        index: targetSub.index,
+        duration: targetSub.duration
+    } : null;
+};

findSub.js

@@ -1,22 +1,22 @@
 #!/usr/bin/env node
 import fs from 'fs';
 import path from 'path';
+import subtitleMerge from "subtitle-merge";
 import {config} from './config.js';
-import {findIndex} from './findIndex.js';
+import {findSub} from './findSub.js';
 import {analyzeMedia} from "./analyzeMedia.js";
 import {extractSub} from "./extractSub.js";
-import {mergeSrtFiles} from "./mergeSub.js";
 import {deleteFile, removeExtension} from "./utils.js";
 
 const main = async () => {
     const mediaFiles = fs.readdirSync(config.workdir).filter((file) => config.exts.includes(path.extname(file)));
 
     for (const file of mediaFiles) {
         console.log(`正在处理：${file}`);
-        const mediaInfo = await analyzeMedia(file);
-        const subIndex = findIndex(mediaInfo);
-        const srts = await extractSub(file, subIndex);
-        mergeSrtFiles(srts[0], srts[1], `${removeExtension(file)}.${config.srtTag}.srt`);
+        const subTitles = await analyzeMedia(file);
+        const targetSubs = findSub(subTitles);
+        const srts = await extractSub(file, targetSubs);
+        subtitleMerge(config.workdir + srts[0], config.workdir + srts[1], `${config.workdir}${removeExtension(file)}.${config.srtTag}.srt`);
         deleteFile(srts[0]);
         deleteFile(srts[1]);
     }