Live Transcription for Conferencing (Closed Captions - Beta)

100ms real-time transcription engine generates a live transcript (closed captions) during a conferencing session. The SDK provides a callback with the transcript for each peer when they speak.

Minimum Requirements

• Minimum 100ms SDK version required is 1.12.0

How to check if captions are started in a room?

To check if live captions are enabled in a room, check if transcriptionState of type caption is in started state in HMSRoom object like below:

let captionsEnabled = hmsSDK.room?.transcriptionStates?.first { $0.state == HMSTranscriptionStatus.started } != nil }

How to implement closed captioning?

Implement on(transcripts: HMSTranscripts) from HMSUpdateListener callback like below:

public func on(transcripts: HMSTranscripts) {
    transcripts.transcripts.forEach { transcript in
        // handle transcript
    }
}

Here is an example implemenation:

    public func on(transcripts: HMSTranscripts) {
        transcripts.transcripts.forEach { transcript in
            let peerModel = transcript.peer
            
            if !(lastTranscript?.isFinal ?? false) {
                _ = self.transcriptArray.popLast()
            }
            
            if peerModel == lastTranscript?.peer {
                self.transcriptArray += [" " + transcript.transcript]
            }
            else {
                // if last transcript was not final pop the speaker label as well
                if !(lastTranscript?.isFinal ?? false) {
                    if transcriptArray.last?.contains(":") ?? false {
                        _ = self.transcriptArray.popLast()
                    }
                }
                self.transcriptArray += ["\n**\(peerModel.name.trimmingCharacters(in: .whitespacesAndNewlines)):** "]
                self.transcriptArray += ["\(transcript.transcript)"]
            }
            
            lastTranscript = transcript
        }
    }

How to toggle Live Transcriptions on/off

You can toggle live transcriptions on/off at runtime that can help save costs. Use startTranscription() method to start the transcription and stopTranscription() method to stop transcription like below:

    // Start Real Time Transcription
    sdk.startTranscription() { success, error in
        if let error = error {
            // handle error
        } else {
            // success
        }
    }

    // Stop Real Time Transcription
    sdk.stopTranscription() { success, error in
        if let error = error {
            // handle error
        } else {
            // success
        }
    }