MP4 INPUT / JSON TRANSCRIPT EXPORT

Get timed JSON speech data from an MP4 video

An MP4 webinar, lecture or interview can become a structured JSON speech transcript with text and timed segments. LongScribe processes the audible voice track; it does not read slides, serialize video frames, identify people by sight or turn on-screen captions into an OCR document.

20 transcriptions + 60 min / month Try without an account Handles long recordings No install Source file kept temporarily, then deleted automatically

FROM RECORDING TO EDITABLE TEXT

From MP4 speech to timed JSON transcript segments

Upload a compatible .mp4 recording with audible speech, review the transcript after processing, and open Download to save JSON.

TXTSRTVTTDOCXJSON

Example transcript

00:00Upload the recording directly from your computer.

00:14Long audio continues processing while you are away.

00:29Return to searchable text with timestamps and exports.

An MP4 needs an audible speech track

An MP4 container can use several codecs. Silent screen recordings, video-only slides, encrypted tracks and unsupported codecs cannot produce meaningful recognized speech.

JSON can map words to a video timeline

The standard file contains a title and segments array, each with speech text and numeric start/end seconds. These are approximate ranges, not word-perfect markers.

Speech is different from on-screen material

The transcript cannot see charts, printed slide titles, faces or scene cuts. Spoken remarks may not match the words displayed in the video.

Choose JSON, SRT or VTT for different uses

JSON is suited to a custom data pipeline; SRT/VTT are timed captions. DOCX and TXT are editable text, and this service does not burn subtitles into MP4 frames.

Review multi-speaker and musical sections

Background music and simultaneous speakers can distort timing and recognition. Replay important figures, names and quotations before publishing.

How to turn MP4 speech into JSON

Choose an authorized .mp4 video recording containing audible speech. The quick form displays its file-size limit; larger eligible Premium recordings require the main app's chunked uploader.
Upload to begin AI speech-to-text. Wait for the job to finish, then check people, numbers and timestamps in the transcript.
On the completed job, open Download on the completed job and select JSON. The download is a structured JSON transcript.

Format warning: The transcription uses the audio track, not text shown in video frames.

Export detail: JSON represents transcript segments/metadata, not decoded media bytes. A recording without understandable speech cannot yield meaningful transcript text.

Free account: 60 transcription minutes across 20 jobs per month, subject to per-job, file-size and source restrictions. Trying without an account can return a shortened preview instead of a full downloadable job.

Browse all supported input/output formats. For large recordings, go through the main uploader; you can select the same export format after processing.

Illustrative MP4 speech timeline JSON

{
  "title": "Webinar (illustrative)",
  "segments": [
    {
      "start": 0.0,
      "end": 3.1,
      "text": "We will review the project timeline."
    },
    {
      "start": 3.1,
      "end": 6.2,
      "text": "The next deadline is in May."
    }
  ]
}

Invented speech segments; no video image content or measured word-level timings.

Frequently asked questions

Does MP4 to JSON export video frames?

No. It only exports recognized speech segments as text.

Can it read text from presentation slides?

No. This workflow transcribes audible speech, not video OCR.

Are transcript times available in JSON?

Yes. Segment start and end fields contain numeric seconds.

Can I also download SRT from my MP4?

Yes, from the same completed transcription job.

What happens when an MP4 is silent?

There is no meaningful speech transcript without spoken audio.

Convert MP4 to JSON →