Auto captions for long videos and audio on Windows

Most caption tools are fine for a one-minute clip and then struggle on a 20-minute video: the import takes minutes, and the captions never finish or fail at the end. PointerStudio, the free Windows screen recorder and editor by Khizoft, was reworked in version 1.0.9 for long files. This page explains how it works and what to expect.

What changed for long files

Fast import. An H.264 MP4 or MOV opens in the editor in about a second or two, because PointerStudio uses the file as it is instead of converting a copy first. The filmstrip and waveform fill in while you work.
Hour-long audio. A sound file of one hour imports in seconds, so you can caption a podcast, a lecture or a voice-over without a video.
Captions in parts. The sound is read in short parts of about 30 seconds, cut at pauses. The first captions appear on the timeline within seconds while the rest keep coming.
Cancel and Resume. Cancel keeps the captions made so far. Resume continues from the last finished part, even after you close the app.
A failed part is retried alone. One bad part does not throw away the whole job.

How to caption a long video

Download PointerStudio and install it.
On Home, choose Import media and pick your video or audio file.
Open the Text & Captions tab and choose Generate captions from audio.
Choose Fast, Balanced or Accurate. For sound longer than 20 minutes PointerStudio first tells you about how long it will take.
Watch the captions arrive. Cancel any time, or Resume later.
Pick one of the caption styles, drag the captions where you want them on the video, and export an MP4.

How long does it take?

It depends on your computer and the quality you choose. On our test PC (8 logical cores, 16 GB of memory) a 20-minute speech file finished in about 1 minute 40 seconds and a 60-minute file in about 4.5 minutes on Balanced, and the first captions showed up after roughly 15 to 20 seconds. Your times will differ: Fast is quicker and makes more mistakes, Accurate uses the biggest model and is slower. The estimate shown before a long run is based on those measurements.

English only, on your computer

Auto captions are for English speech today. They are made on your own computer: after a one-time model download your audio is not uploaded anywhere. Other languages are not supported yet, so check the result before you publish.

Tips for better captions

Use a clear microphone and keep music quieter than the voice.
Pick Accurate for interviews or fast speakers and Fast for a quick draft.
Fix names and product terms by clicking a caption and editing its text.
Style all captions at once, then move one caption alone with Alt + drag if you need to.

Frequently asked questions

Can PointerStudio add captions to a 1-hour video?

Yes. Captions are made in parts of about 30 seconds, the first ones appear within seconds, and on our test PC a 60-minute file finished in about 4.5 minutes on Balanced.

Can I caption audio without a video?

Yes. Import an audio file such as MP3 or WAV and generate captions from it.

What if the captions stop halfway?

Press Resume. PointerStudio continues from the last finished part, and a part that fails is retried alone.

Which languages are supported?

English only today.

Are my files uploaded?

No. Captions are made on your computer after a one-time model download.

Download PointerStudio for Windows

Free for Windows 10 and 11. No watermark, no time limit.