Using live transcription in FAB Subtitler LIVE

This page contains information on how to use live transcription functionality for transmission of live subtitles with FAB Subtitler LIVE.

You will find information on how to configure live transcription in FAB Subtitler on a separate page

You will find information on how to use Live Transcription in FAB Subtitler BCAST on a separate page

FAB Subtitler also supports transcription of video/audio files that is described on a separate page

Introduction to live transcription

Any video/audio that can be reproduced in FAB Subtitler LIVE can be used for live transcription (live video and also video files). When live transcription is activated FAB Subtitler sends live audio to the cloud and receives the recognized text with a few seconds delay and transmits the recognized text as subtitles. Subtitles can be transmitted in block mode as complete subtitle or in word by word mode to reduce the delay for the viewer.

Live transcription is available in FAB Subtitler LIVE in manual and also automatic mode. In manual mode an operator activates/deactivates live transcription and has the possibility to correct recognized texts. In automatic mode the playout/automation system can activate/deactivate live transcription using HTTP REST API.

Using Live Transcription

FAB Subtitler can transfer live audio received over SDI video or IP video to the live transcription service and transmit live subtitles with texts that are recognized by the live transcription service.

To be able to use this functionality it is first necessary to configure the “Video in a Window” functionality in FAB Subtitler correctly so that FAB Subtitler will receive live video/audio and display it on the PC monitor. Find out how on this page.

To display live video first create a new subtitle file and then click on “Display / Editor over video”. After the video is displayed on the PC monitor and you also hear the audio you can activate the transfer of the audio to the transcription service by:

  • Click on “News” in the ribbon.
  • Then click on “Speech Interface” to display a window with the speech interface.
  • Enable or disable “Automatic Mode” depending on whether you wish to transmit recognized text automatically or if you wish to be able to correct the text before transmitting the text as subtitles.
  • Then click on “Transcribe from Video” or “Transcribe from Microphone”

The recognized text will appear in the speech interface window.

Alternatively for testing purposes it is also possible to use a video file as a source for live transcription. In such case simply open a video file in FAB Subtitler, play the file and click on “Transcribe from Video”. The played audio from the video file will be sent to the live transcription service and the transcribed text will appear in the speech interface.

Detailed information about the speech interface can be found here: How to use the speech interface.

Controlling Live transcription using RESTful API

To control (start or stop) the live transcription over HTTP with the RESTful API, the automatic operation mode has to be enabled and configured.

To enable the RESTful API over http please configure FAB Subtitler the following way:

  • In Options/Special/Automation configure the following:

Live transcription automation configuration

Detailed information on how to check, whether the RESTful API is available can be found here: Configuring RESTful service API

  • Start the Automatic mode in Extras / Tools / Start automatic mode:

Start automatic mode

  • A new window “Live transcription status” will appear in the top right corner allowing the user to manually stop the automatic mode and control the transcription if required:

Live transcription status

FAB Subtitler LIVE and MPEG offer a RESTful service API, which can be used to control the Live transcription over http to perform the following actions:

  • START the live transcription
  • STOP the live transcription

The following parameters, which are optional, can be defined:

  • provider: None, Azure, Google, Scriptix
  • language
  • filename
  • useMic – transcribe from mic or from received live video

If the parameter isn’t explicitly defined, the FAB Subtitler will select the default parameter as it is defined in “Options” and useMIC will be set to “False”.

Example REST API requests:

Start live transcription request: GET /livetranscription/start
Example: GET http://ip:port/livetranscription/start?language=de-DE&provider=Google&filename=transcription.stl&useMic=False
Simplified example: GET http://ip:port/livetranscription/start

Stop live transcription request: GET /livetranscription/stop
Example: http://ip:port/livetranscription/stop

This page was last updated on 2021-05-21