// ==UserScript==
// @name Youtube 双语字幕版
// @version 1.4.0
// @author LR
// @license MIT
// @description YouTube双语字幕,任何语言翻译成中文或用户选择的目标语言。支持YouTube翻译和谷歌翻译,自动切换。支持移动端和桌面端,适配Via浏览器。
// @match *://www.youtube.com/*
// @match *://m.youtube.com/*
// @require https://unpkg.com/ajax-hook@latest/dist/ajaxhook.min.js
// @grant GM_registerMenuCommand
// @run-at document-start
// @namespace https://greasyfork.org/users/1210499
// @icon https://www.youtube.com/s/desktop/b9bfb983/img/favicon_32x32.png
// ==/UserScript==
(function () {
'use strict';
// 设置
const DEFAULT_LANG = 'zh';
let TARGET_LANG = DEFAULT_LANG;
const DEFAULT_TRANS_SERVICE = 'youtube';
let TRANS_SERVICE = DEFAULT_TRANS_SERVICE;
let LAST_FAILED_SERVICE = null; // 记录上次失败的服务
// 获取用户设置
function getUserSettings() {
return {
lang: localStorage.getItem('dualSubTargetLang') || DEFAULT_LANG,
service: localStorage.getItem('dualSubTransService') || DEFAULT_TRANS_SERVICE
};
}
// 保存用户设置
function saveUserSettings(lang, service) {
localStorage.setItem('dualSubTargetLang', lang);
localStorage.setItem('dualSubTransService', service);
TARGET_LANG = lang;
TRANS_SERVICE = service;
}
// 添加设置菜单
function addSettingsMenu() {
if (typeof GM_registerMenuCommand === 'function') {
GM_registerMenuCommand('设置翻译语言', async () => {
const userInput = prompt('请输入目标语言的ISO 639-1代码(例如:zh 中文, en 英文, ja 日语):', TARGET_LANG);
if (userInput) {
saveUserSettings(userInput.trim(), TRANS_SERVICE);
alert(`翻译目标语言已设置为:${userInput.trim()}`);
}
});
GM_registerMenuCommand('选择翻译引擎', async () => {
const userInput = prompt('请选择翻译引擎(输入数字):\n1. YouTube 翻译\n2. Google 翻译', TRANS_SERVICE === 'youtube' ? '1' : '2');
if (userInput) {
const service = userInput.trim() === '1' ? 'youtube' : 'google';
saveUserSettings(TARGET_LANG, service);
LAST_FAILED_SERVICE = null; // 重置失败记录
alert(`翻译引擎已设置为:${service === 'youtube' ? 'YouTube 翻译' : 'Google 翻译'}`);
}
});
}
}
// 初始化设置
const settings = getUserSettings();
TARGET_LANG = settings.lang;
TRANS_SERVICE = settings.service;
addSettingsMenu();
// 谷歌翻译API
async function googleTranslate(text) {
try {
const response = await fetch(`https://translate.googleapis.com/translate_a/single?client=gtx&sl=auto&tl=${TARGET_LANG}&dt=t&q=${encodeURIComponent(text)}`);
if (!response.ok) throw new Error('Google API请求失败');
const data = await response.json();
return data[0][0][0];
} catch (error) {
console.error('Google翻译失败:', error);
return null; // 返回null表示翻译失败
}
}
async function enableDualSubtitles() {
// 获取翻译后的字幕数据
async function fetchTranslatedSubtitles(url, preferredService = TRANS_SERVICE) {
// 如果上次失败的服务和当前首选服务相同,自动切换到另一个服务
if (LAST_FAILED_SERVICE === preferredService) {
preferredService = preferredService === 'youtube' ? 'google' : 'youtube';
console.log(`上次${LAST_FAILED_SERVICE}翻译失败,自动切换到${preferredService}`);
}
async function tryYouTubeTranslation() {
const cleanUrl = url.replace(/(^|[&?])tlang=[^&]*/g, '') + `&tlang=${TARGET_LANG}&translate_h00ked`;
try {
const response = await fetch(cleanUrl, { method: 'GET' });
if (!response.ok) throw new Error('YouTube翻译请求失败');
const data = await response.json();
// 验证返回的数据是否有效
if (!data.events || data.events.length === 0) throw new Error('YouTube返回的字幕数据无效');
return data;
} catch (error) {
console.error('YouTube翻译失败:', error);
LAST_FAILED_SERVICE = 'youtube';
return null;
}
}
async function tryGoogleTranslation() {
try {
const response = await fetch(url, { method: 'GET' });
if (!response.ok) throw new Error('获取原字幕失败');
const data = await response.json();
const translatedData = JSON.parse(JSON.stringify(data));
// 批量收集需要翻译的文本
const textToTranslate = translatedData.events
.filter(event => event.segs)
.map(event => ({
text: event.segs.map(seg => seg.utf8).join('').trim(),
event: event
}))
.filter(item => item.text);
// 批量翻译
const results = await Promise.all(
textToTranslate.map(async ({ text, event }) => {
const translatedText = await googleTranslate(text);
if (translatedText === null) throw new Error('Google翻译失败');
return { event, translatedText };
})
);
// 更新翻译结果
results.forEach(({ event, translatedText }) => {
event.segs = [{ utf8: translatedText }];
});
return translatedData;
} catch (error) {
console.error('谷歌翻译失败:', error);
LAST_FAILED_SERVICE = 'google';
return null;
}
}
// 尝试首选服务
let result = null;
if (preferredService === 'youtube') {
result = await tryYouTubeTranslation();
if (!result) {
console.log('YouTube翻译失败,尝试使用谷歌翻译');
result = await tryGoogleTranslation();
}
} else {
result = await tryGoogleTranslation();
if (!result) {
console.log('谷歌翻译失败,尝试使用YouTube翻译');
result = await tryYouTubeTranslation();
}
}
return result;
}
// 编辑距离计算
function levenshteinDistance(s1, s2) {
if (s1.length === 0) return s2.length;
if (s2.length === 0) return s1.length;
const matrix = Array.from({ length: s1.length + 1 }, (_, i) => Array(s2.length + 1).fill(0).map((_, j) => (i === 0 ? j : i)));
for (let i = 1; i <= s1.length; i++) {
for (let j = 1; j <= s2.length; j++) {
matrix[i][j] = (s1[i - 1] === s2[j - 1])
? matrix[i - 1][j - 1]
: Math.min(
matrix[i - 1][j - 1] + 1,
matrix[i][j - 1] + 1,
matrix[i - 1][j] + 1
);
}
}
return matrix[s1.length][s2.length];
}
// Jaccard相似度计算
function jaccardSimilarity(str1, str2) {
const set1 = new Set(str1.split(''));
const set2 = new Set(str2.split(''));
const intersection = [...set1].filter(x => set2.has(x)).length;
const union = new Set([...set1, ...set2]).size;
return intersection / union;
}
// 相似度计算
function calculateSimilarity(s1, s2) {
const maxLength = Math.max(s1.length, s2.length);
const levenshteinSimilarity = 1 - (levenshteinDistance(s1, s2) / maxLength);
const jaccardSim = jaccardSimilarity(s1, s2);
return (levenshteinSimilarity * 0.7) + (jaccardSim * 0.3);
}
// 合并字幕
function mergeSubtitles(defaultSubs, translatedSubs) {
const mergedSubs = JSON.parse(JSON.stringify(defaultSubs));
const translatedEvents = translatedSubs.events.filter(event => event.segs);
const translatedMap = new Map(translatedEvents.map(event => [event.tStartMs, event]));
for (let i = 0; i < mergedSubs.events.length; i++) {
const defaultEvent = mergedSubs.events[i];
if (!defaultEvent.segs) continue;
const translatedEvent = [...translatedMap.keys()].reduce((closest, tStartMs) => {
return (Math.abs(tStartMs - defaultEvent.tStartMs) < Math.abs(closest - defaultEvent.tStartMs)) ? tStartMs : closest;
}, Infinity);
const eventToMerge = translatedMap.get(translatedEvent);
if (eventToMerge) {
const defaultText = defaultEvent.segs.map(seg => seg.utf8).join('').trim();
const translatedText = eventToMerge.segs.map(seg => seg.utf8).join('').trim();
const timeOverlap = Math.min(defaultEvent.tStartMs + defaultEvent.dDurationMs, eventToMerge.tStartMs + eventToMerge.dDurationMs) - Math.max(defaultEvent.tStartMs, eventToMerge.tStartMs);
if (timeOverlap > 0) {
const similarity = calculateSimilarity(defaultText, translatedText);
// 使用0.6容错率
if (similarity < 0.6) {
defaultEvent.segs = [{
utf8: `${defaultText}\n${translatedText}`,
tStartMs: defaultEvent.tStartMs,
dDurationMs: defaultEvent.dDurationMs
}];
}
}
}
}
return JSON.stringify(mergedSubs);
}
// ajax-hook代理
ah.proxy({
onResponse: async (response, handler) => {
if (response.config.url.includes('/api/timedtext') && !response.config.url.includes('&translate_h00ked')) {
try {
const defaultSubs = JSON.parse(response.response);
const translatedSubs = await fetchTranslatedSubtitles(response.config.url);
if (translatedSubs) {
response.response = mergeSubtitles(defaultSubs, translatedSubs);
}
} catch (error) {
console.error("处理字幕时出错:", error);
}
}
handler.resolve(response);
}
});
}
enableDualSubtitles();
})();