Learn languages with Rolko

Supported subtitle text, not pixel OCR

How to understand Chinese characters in videos

If a supported video exposes usable Chinese subtitles or a transcript, Rolko can make that text interactive for pinyin, meaning, saving, and review. Chinese characters baked directly into video pixels or images are different: they require OCR, which Rolko does not currently provide. This page helps you choose the truthful workflow.

Start learning

The web app works in every modern browser. No extension required.

Interactive product proof

Use interactive subtitles when real text is available

The demo shows Rolko working with supported subtitle text while the video remains visible.

N
学中文说汉语听读
后来我发现，这座城市比想象中更温柔。★
0:00 / 0:12
↑Netflix-style overlay — tap or hover a word to explore

Rolko-specific evidence

What this workflow actually supports

Last verified . Checked against Rolko’s current browser-capability gate, Chrome extension manifest 0.2.17, public routes, and shared interactive product demos.

Rolko compatibility and support matrix
SurfaceCurrent supportImportant limitation
Desktop browser extensionSupported desktop Chromium-family browsersThe install path is not offered to Safari, Firefox, Android, or iOS. Website access is requested from a user action.
Mobile web appReading, vocabulary, and reviewThe watch-page and webpage-hover browser-extension workflows are desktop-only.
YouTubeInteractive subtitles and supported transcript importRequires usable captions in the active study language; not every video exposes a supported transcript.
NetflixInteractive subtitles on supported watch pagesRequires usable subtitles in the active study language; title and page-state support can vary.
Normal webpagesSelectable Chinese textImage, canvas, protected, or unusually structured text may not be available. Rolko does not provide OCR.
Transcript importSupported sources in the Rolko web appRequires a source and transcript that Rolko can retrieve or accept.

Worked example: from Chinese subtitle text to review

The Netflix-style demo uses the shared Rolko player and dictionary contract: subtitle tokens remain text while the scene stays visible.

  1. Start with a supported subtitle

    The canonical Chengdu demo exposes Chinese subtitle text in a supported desktop Netflix-style player.

  2. Inspect 城市

    Open the interactive token 城市 to see “chéngshì” and the dictionary meaning “city; town; urban area.”

  3. Save its vocabulary state

    The real player uses Rolko’s shared vocabulary controls; with a signed-in account and a plan that permits new-word saving, mark the word Learning or Learned.

  4. Continue with text or review

    Use supported transcript text in the web app or review saved vocabulary with spaced repetition; pixel OCR remains outside Rolko’s current workflow.

Product workflow

Choose the workflow based on the text source

01

Subtitle text

Use the desktop extension when a supported watch page exposes usable Chinese subtitles.

02

Transcript text

Import a supported transcript into the web app and read it line by line.

03

Text inside pixels

Use an OCR tool for characters baked into an image or video frame; Rolko does not currently extract them.

Continue in Rolko

Use a supported transcript when subtitle import is available

A supported transcript can become interactive text in the Rolko web app even when you prefer to study away from the watch page.

Reading workspace

学中文的秘诀

Tap or hover a word for its pronunciation and meaning. Mark it as learned or learning.

Word Coverage

Learned: 50%Learning: 20%New: 30%
主持人
你学中文多久了？
嘉宾
大概三年了，但是每天都要练习。
主持人
有什么好的学习方法吗？
嘉宾
我觉得看中文剧最有用，边看边学。

Related Rolko answers

Continue with the workflow you need

What is Rolko, and when should you use it?

Rolko is a language-learning web app and browser extension for interactive subtitles, webpage text, vocabulary tracking and spaced-repetition review.

A focused Language Reactor alternative for learning Chinese

Looking for a Language Reactor alternative focused on Chinese? Use Rolko to explore Chinese subtitles, save useful words and review them with spaced repetition.

Learn Chinese with Netflix subtitles

Learn Chinese with supported Netflix subtitles on desktop. Explore words for pinyin and meaning, save vocabulary and review it later with Rolko.

Learn Chinese with YouTube subtitles

Learn Chinese with supported YouTube subtitles. Explore words on desktop or import an available Chinese transcript into the Rolko web app.

A Chinese popup dictionary that also remembers your words

Use Rolko to explore normal Chinese webpage text for pinyin and meaning, save useful words and keep them in one vocabulary and review workflow.

Track the Chinese words you meet in real content

Track Chinese words from supported subtitles, webpages and imported text in Rolko, then review saved vocabulary with spaced repetition.

Common questions

What to know before you start

Can Rolko hover Chinese text inside a video image?

No. Rolko can make supported subtitle text interactive, but it does not currently detect text baked into video pixels.

What is the difference between subtitles and OCR?

Subtitles are text supplied by the video platform or track. OCR attempts to recognize characters from image pixels. Rolko currently supports selected subtitle and transcript workflows, not pixel OCR.

Can I use Rolko when a video has Chinese captions?

Yes, on a supported desktop watch page when usable Chinese subtitle text is available.

Can I import the transcript instead?

Yes, when Rolko supports the source and a transcript is available. Imported transcript text can be read and studied in the web app.

Does subtitle support work for every video?

No. Support depends on the platform, page structure, browser, and availability of usable Chinese subtitles or transcript data.