Amazon Transcribe
Developer Guide

Channel Identification

When an audio file has multiple channels that you want to transcribe into separate transcriptions that identify the channel that contains the speech, use channel identification. For example, if you have a customer support representative on one channel and a customer on another, use channel identification to create a transcription that is identified by each channel and a single transcription that combines them.

Amazon Transcribe splits your audio file into multiple channels and transcribes the channels separately. After transcribing all channels, Amazon Transcribe also merges the transcriptions to create a single transcription. It returns all of the transcriptions in a single result file.

Speakers' utterances are ordered by their start time. An utterance is a unit of speech on the audio channel that is typically separated from other utterances by silence. If an utterance on one channel overlaps one on another channel, Amazon Transcribe orders them in the transcription by their start times. Utterances that overlap in the input audio don't overlap in the transcription output.

You can enable channel identification in the Amazon Transcribe console or with the API. In the console, choose Channel identification when you create the transcription job. When you use the API, set the ChannelIdentification flag when you call the StartTranscriptionJob operation.

The following is the abbreviated output for a conversation on two channels:

{ "jobName": "job id", "accountId": "account id", "results": { "transcripts": [ { "transcript": "When you try ... It seems to ..." } ], "channel_labels": { "channels": [ { "channel_label": "ch_0", "items": [ { "start_time": "12.282", "end_time": "12.592", "alternatives": [ { "confidence": "1.0000", "content": "When" } ], "type": "pronunciation" }, { "start_time": "12.592", "end_time": "12.692", "alternatives": [ { "confidence": "0.8787", "content": "you" } ], "type": "pronunciation" }, { "start_time": "12.702", "end_time": "13.252", "alternatives": [ { "confidence": "0.8318", "content": "try" } ], "type": "pronunciation" }, Transcription abbreviated ] }, { "channel_label": "ch_1", "items": [ { "start_time": "12.379", "end_time": "12.589", "alternatives": [ { "confidence": "0.5645", "content": "It" } ], "type": "pronunciation" }, { "start_time": "12.599", "end_time": "12.659", "alternatives": [ { "confidence": "0.2907", "content": "seems" } ], "type": "pronunciation" }, { "start_time": "12.669", "end_time": "13.029", "alternatives": [ { "confidence": "0.2497", "content": "to" } ], "type": "pronunciation" }, Transcription abbreviated ] } }