AWS Transcribe Engine User Guide | Kamiwaza Docs

Version: 1.0.1 (Latest)

AWS Transcribe provides enterprise-grade, managed speech-to-text capabilities through Kamiwaza's unified transcription API. Audio is processed by AWS's cloud service, eliminating local compute requirements.

Prerequisites

Before registering an AWS Transcribe endpoint, make sure:

Minimum IAM policy:

{
  "Version": "2012-10-17",
  "Statement": [\
    {\
      "Effect": "Allow",\
      "Action": [\
        "transcribe:StartTranscriptionJob",\
        "transcribe:GetTranscriptionJob",\
        "transcribe:DeleteTranscriptionJob"\
      ],\
      "Resource": "*"\
    },\
    {\
      "Effect": "Allow",\
      "Action": ["s3:PutObject", "s3:GetObject", "s3:DeleteObject"],\
      "Resource": "arn:aws:s3:::YOUR-BUCKET/transcribe-jobs/*"\
    }\
  ]
}

Quick Start (UI)

  1. In Kamiwaza, go to Models, click Add Model, then click Add external inference endpoint in the dialog header.

  2. On the Source step, choose AWS under Where is your model hosted?, then choose Transcribe (transcription) under Service. Click Next.

  3. On the Setup step, fill in the form:

    • Display Name — Friendly name shown in the Kamiwaza UI.
    • Description (optional) — Free-form note for other operators.
    • AWS Region — The region where audio will be processed (for example us-east-1). Must match the S3 bucket's region. Required.
    • S3 Bucket — The bucket Kamiwaza will use to stage batch audio and transcript artifacts. Must be in the same region. Required.
    • IAM Access Key — Paste the Access Key ID and Secret Access Key.
    • Show advanced options (optional) — Reveals a Language field for setting a default language. Leave it unset to let Transcribe auto-detect the language on each batch request (see Supported Languages).
  4. Click Save Endpoint.

  5. Deploy the model from the Models list.

Use long-lived IAM credentials. Temporary or session credentials expire while a deployment is running and lead to silent authentication failures.

Credentials

Credentials registered through the form are encrypted on save and stored in the Kamiwaza secret catalog, keyed by AWS region. Catalog reuse across endpoints in the same region, rotation through the Edit form, and the five-minute propagation window are described in External endpoints overview. The stored secret is JSON containing your long-lived AWS keys:

{
  "aws_access_key_id": "AKIA...",
  "aws_secret_access_key": "..."
}

If you've already registered an AWS Bedrock endpoint in the same region with IAM access-key auth, Kamiwaza recognizes the existing credential and offers Use existing credential during registration. Bedrock endpoints registered with the Bedrock API Key auth path store a bearer token, not AWS keys, and cannot be reused for Transcribe — Transcribe requires IAM access keys.

Rotate long-lived IAM credentials regularly. Treat the registered access key like any other long-lived AWS credential — rotate on the same cadence as your cloud key inventory and monitor AccessKeyLastUsed in IAM. Rotated credentials propagate to running deployments through the Edit form within the engine credential cache window (~5 minutes).

API Usage

Transcribe Audio (Batch)

curl -X POST "https://<your-domain>/runtime/models/<deployment-id>/v1/audio/transcriptions" \
  -H "Authorization: Bearer $TOKEN" \
  -F "file=@recording.wav" \
  -F "response_format=json"

Transcribe Audio (Streaming)

curl -X POST "https://<your-domain>/runtime/models/<deployment-id>/v1/audio/transcriptions" \
  -H "Authorization: Bearer $TOKEN" \
  -F "file=@recording.pcm" \
  -F "stream=true"

Streaming returns Server-Sent Events (SSE) with partial results.

Note: Streaming only supports pcm, ogg, and flac formats. The format is auto-detected from the file extension. Streaming always uses the registered language (set via Show advanced options on the registration form); if none is registered it defaults to en-US. The per-request language parameter is ignored on streaming.

Request Parameters

Parameter Required Description
file Yes Audio file (multipart form-data)
response_format No text, json (default), or verbose_json
language No BCP-47 code. Overrides the registered language on batch requests; ignored on streaming requests, which always use the registered language (or en-US if none is registered).
stream No true for streaming mode

Response Formats

json (default)

{
  "text": "Hello, how are you today?"
}

text

Hello, how are you today?

verbose_json

{
  "task": "transcribe",
  "language": "en",
  "duration": 3.45,
  "text": "Hello, how are you today?",
  "segments": [\
    { "id": 0, "start": 0.0, "end": 1.2, "text": "Hello," },\
    { "id": 1, "start": 1.3, "end": 3.4, "text": "how are you today?" }\
  ]
}

Batch vs Streaming

Feature Batch Streaming
Audio formats mp3, mp4, wav, flac, ogg, amr, webm pcm, ogg, flac
Max duration 15 minutes (Kamiwaza default job_timeout_seconds; AWS-side hard limit is 4 hours) 5 minutes (300s, AWS-side limit)
Auto language detection Yes No (defaults to en-US)
Latency Higher (job-based) Real-time
Use case Recorded audio Live audio

Supported Languages

AWS Transcribe supports 100+ languages for batch and 30+ for streaming.