vCon World Transcription Format Extension
draft-howe-vcon-wtf-extension-01
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| Document | Type | Active Internet-Draft (individual) | |
|---|---|---|---|
| Author | Thomas McCarthy-Howe | ||
| Last updated | 2025-10-06 | ||
| RFC stream | (None) | ||
| Intended RFC status | (None) | ||
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| Stream | Stream state | (No stream defined) | |
| Consensus boilerplate | Unknown | ||
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| IESG | IESG state | I-D Exists | |
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draft-howe-vcon-wtf-extension-01
vCon T. McCarthy-Howe
Internet-Draft VCONIC
Intended status: Standards Track 6 October 2025
Expires: 9 April 2026
vCon World Transcription Format Extension
draft-howe-vcon-wtf-extension-01
Abstract
This document defines the World Transcription Format (WTF) extension
for Virtualized Conversations (vCon). The WTF extension provides a
standardized analysis framework for representing speech-to-text
transcription data from multiple providers within vCon containers.
This extension defines a comprehensive analysis format that enables
consistent transcription processing, quality assessment, and
interoperability across different transcription services while
preserving provider-specific features through extensible fields.
The WTF extension is designed as a Compatible Extension that
introduces a new analysis type for transcription data without
altering existing vCon semantics, ensuring backward compatibility
with existing vCon implementations.
About This Document
This note is to be removed before publishing as an RFC.
The latest revision of this draft can be found at https://vcon-
dev.github.io/draft-howe-vcon-wtf-extension/draft-howe-vcon-wtf-
extension-01.html. Status information for this document may be found
at https://datatracker.ietf.org/doc/draft-howe-vcon-wtf-extension/.
Discussion of this document takes place on the vCon Working Group
mailing list (mailto:vcon@ietf.org), which is archived at
https://mailarchive.ietf.org/arch/browse/vcon/. Subscribe at
https://www.ietf.org/mailman/listinfo/vcon/.
Source for this draft and an issue tracker can be found at
https://github.com/vcon-dev/draft-howe-vcon-wtf-extension.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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Table of Contents
1. Requirements Language . . . . . . . . . . . . . . . . . . . . 3
2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Conventions and Definitions . . . . . . . . . . . . . . . . . 4
3.1. Core Terms . . . . . . . . . . . . . . . . . . . . . . . 4
4. World Transcription Format Overview . . . . . . . . . . . . . 5
4.1. Design Principles . . . . . . . . . . . . . . . . . . . . 5
4.2. Core Structure . . . . . . . . . . . . . . . . . . . . . 6
5. vCon WTF Extension Definition . . . . . . . . . . . . . . . . 6
5.1. Extension Classification . . . . . . . . . . . . . . . . 6
5.2. Extension Registration . . . . . . . . . . . . . . . . . 6
5.3. Extension Usage . . . . . . . . . . . . . . . . . . . . . 7
6. WTF Analysis Structure . . . . . . . . . . . . . . . . . . . 7
6.1. Analysis Storage . . . . . . . . . . . . . . . . . . . . 7
6.2. WTF Analysis Schema . . . . . . . . . . . . . . . . . . . 8
6.2.1. Required Fields . . . . . . . . . . . . . . . . . . . 8
6.2.2. Optional Fields . . . . . . . . . . . . . . . . . . . 10
7. Provider Integration Guidelines . . . . . . . . . . . . . . . 11
7.1. Supported Providers . . . . . . . . . . . . . . . . . . . 11
7.2. Conversion Requirements . . . . . . . . . . . . . . . . . 11
7.3. Provider-Specific Mappings . . . . . . . . . . . . . . . 12
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7.3.1. Whisper Integration . . . . . . . . . . . . . . . . . 12
7.3.2. Deepgram Integration . . . . . . . . . . . . . . . . 12
8. Quality and Confidence Metrics . . . . . . . . . . . . . . . 12
8.1. Confidence Score Normalization . . . . . . . . . . . . . 12
8.2. Quality Metrics . . . . . . . . . . . . . . . . . . . . . 13
9. Security Considerations . . . . . . . . . . . . . . . . . . . 13
9.1. Data Privacy . . . . . . . . . . . . . . . . . . . . . . 13
9.2. Provider-Specific Security . . . . . . . . . . . . . . . 14
9.3. Integrity Protection . . . . . . . . . . . . . . . . . . 14
9.4. Temporal Validation . . . . . . . . . . . . . . . . . . . 14
10. WTF as an Analysis Framework . . . . . . . . . . . . . . . . 14
10.1. Analysis vs. Storage . . . . . . . . . . . . . . . . . . 14
10.2. Analysis Processing Workflow . . . . . . . . . . . . . . 15
11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15
11.1. vCon Extensions Names Registry . . . . . . . . . . . . . 15
11.2. WTF Analysis Type Values Registry . . . . . . . . . . . 16
11.3. WTF Provider Registry . . . . . . . . . . . . . . . . . 16
12. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . 16
12.1. Basic Two-Party Call Transcription Analysis . . . . . . 16
12.2. Multi-Provider Transcription Analysis Comparison . . . . 20
13. References . . . . . . . . . . . . . . . . . . . . . . . . . 21
13.1. Normative References . . . . . . . . . . . . . . . . . . 21
13.2. Informative References . . . . . . . . . . . . . . . . . 22
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 22
Trademark Notice . . . . . . . . . . . . . . . . . . . . . . . . 23
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 23
1. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 RFC2119 [RFC8174] when, and only when, they appear in all
capitals, as shown here.
2. Introduction
Virtualized Conversations (vCon) [I-D.draft-ietf-vcon-core-00]
provide a standardized container format for conversation data,
enabling interoperability across different communication platforms
and modalities. As speech-to-text technology becomes increasingly
important for conversation analysis, compliance, and accessibility,
there is a growing need for standardized transcription analysis
representation within vCon containers.
Current transcription services each use proprietary formats, making
it difficult to:
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* Switch between transcription providers without data conversion
* Perform comparative analysis across different providers
* Maintain consistent data processing pipelines
* Preserve transcription metadata during system migrations
* Ensure long-term accessibility and archival compliance
This document defines the World Transcription Format (WTF) extension
for vCon, which addresses these challenges by providing a
comprehensive analysis framework that includes:
* A unified analysis schema for transcription data from any speech-
to-text provider
* Hierarchical organization from words to segments to complete
transcripts
* Extensible fields for provider-specific analytical features
* Built-in quality metrics and confidence scoring for analysis
assessment
* Support for real-time and batch transcription analysis workflows
* Consistent export capabilities to standard subtitle and caption
formats
The WTF extension defines a new category of vCon analysis
specifically for speech-to-text transcription. This analysis type
enables organizations to standardize their transcription analysis
workflows while maintaining the flexibility to use multiple providers
and preserve provider-specific analytical enhancements.
3. Conventions and Definitions
3.1. Core Terms
*World Transcription Format (WTF)*: A standardized analysis framework
and JSON schema for representing speech-to-text transcription data
from any provider in a consistent, interoperable format. WTF defines
a comprehensive analysis type for vCon that includes transcription
content, quality metrics, confidence scoring, and provider-specific
analytical features.
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*Transcription Analysis*: The structured representation of speech-to-
text conversion results, including the transcribed text, timing
information, confidence metrics, speaker identification, and quality
assessments.
*Transcription Provider*: A service or system that converts audio or
video content to text, such as Whisper(TM), Deepgram(TM),
AssemblyAI(TM), Google Cloud Speech-to-Text(TM), Amazon
Transcribe(TM), or Azure Speech Services(TM).
*Segment*: A logical chunk of transcribed content, typically
representing sentence or phrase boundaries with associated timing
information and analytical metadata.
*Speaker Diarization*: The process of partitioning an audio stream
into homogeneous segments according to the speaker identity, enabling
"who spoke when" analysis.
*Compatible Extension*: A vCon extension that introduces additional
data without altering the meaning or structure of existing elements,
as defined in [I-D.draft-ietf-vcon-core-00].
4. World Transcription Format Overview
The World Transcription Format defines a comprehensive analysis
framework using a hierarchical JSON structure designed to capture
transcription analysis results at multiple levels of granularity
while maintaining consistency across different providers.
4.1. Design Principles
*Completeness*: WTF captures all essential transcription analysis
data including text, timing, confidence scores, speaker information,
and quality assessments.
*Consistency*: Provides uniform analysis structure regardless of the
underlying transcription provider.
*Extensibility*: Supports provider-specific analytical features
through structured extension fields.
*Validation*: Includes built-in data integrity checking and quality
metrics for analysis assessment.
*Hierarchical Organization*: Natural progression from words to
segments to complete transcripts enables multi-level analysis.
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4.2. Core Structure
WTF uses a hierarchical JSON structure with three required sections
and multiple optional enrichment layers:
{
"transcript": { /* Required: Core transcript information */ },
"segments": [ /* Required: Time-aligned text segments */ ],
"metadata": { /* Required: Processing metadata */ },
"words": [ /* Optional: Word-level details */ ],
"speakers": { /* Optional: Speaker diarization */ },
"alternatives": [ /* Optional: Alternative transcriptions */ },
"enrichments": { /* Optional: Analysis features */ },
"extensions": { /* Optional: Provider-specific data */ },
"quality": { /* Optional: Quality metrics */ },
"streaming": { /* Optional: Streaming information */ }
}
5. vCon WTF Extension Definition
5.1. Extension Classification
The WTF extension is a *Compatible Extension* as defined in
Section 2.5 of [I-D.draft-ietf-vcon-core-00]. This extension:
* Introduces a new analysis type for transcription data without
altering existing vCon semantics
* Defines a comprehensive analysis framework for speech-to-text
results
* Can be safely ignored by implementations that don't support
transcription analysis
* Does not require listing in the must_support parameter
* Maintains backward compatibility with existing vCon
implementations
5.2. Extension Registration
This document defines the "wtf_transcription" extension token for
registration in the vCon Extensions Names Registry:
* *Extension Name*: wtf_transcription
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* *Extension Description*: World Transcription Format - A
standardized analysis framework for speech-to-text transcription
with multi-provider support, quality metrics, and confidence
scoring
* *Change Controller*: IESG
* *Specification Document*: This document
5.3. Extension Usage
vCon instances that include WTF transcription analysis SHOULD include
"wtf_transcription" in the extensions array to indicate support for
the WTF analysis framework:
{
"uuid": "01234567-89ab-cdef-0123-456789abcdef",
"extensions": ["wtf_transcription"],
"created_at": "2025-01-02T12:00:00Z",
"parties": [...],
"dialog": [...],
"analysis": [
{
"type": "wtf_transcription",
"start": "2025-01-02T12:15:30Z",
"party": 0,
"dialog": 0,
"encoding": "json",
"body": {
// WTF transcription analysis data structure defined below
}
}
]
}
6. WTF Analysis Structure
6.1. Analysis Storage
Transcription analysis results MUST be stored as vCon analysis using
the standard analysis object structure defined in Section 4.3 of
[I-D.draft-ietf-vcon-core-00]. The analysis mechanism provides the
association between the analysis results and the corresponding dialog
elements.
The WTF transcription analysis object MUST include:
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* *type*: MUST be set to "wtf_transcription" to identify this as a
WTF analysis
* *encoding*: MUST be set to "json" for structured analysis data
* *body*: MUST contain the WTF transcription analysis data structure
as defined below
The WTF transcription analysis SHOULD include:
* *start*: ISO 8601 timestamp when the transcription analysis was
performed
* *party*: Index of the party in the vCon parties array (for single-
speaker transcription analysis)
* *dialog*: Index of the associated dialog in the vCon dialog array
6.2. WTF Analysis Schema
The body field of the WTF transcription analysis object MUST contain
a JSON object conforming to the WTF analysis schema with the
following structure:
6.2.1. Required Fields
6.2.1.1. Transcript Object
"transcript": {
"text": "string", // Complete transcription text
"language": "string", // BCP-47 language code (e.g., "en-US")
"duration": "number", // Total audio duration in seconds
"confidence": "number" // Overall confidence score \[0.0-1.0\]
}
The transcript object provides the high-level summary of the entire
transcription:
* *text*: The complete, concatenated transcription text
* *language*: MUST use BCP-47 format [BCP47] (examples: "en-US",
"es-MX", "fr-CA")
* *duration*: Floating-point seconds, MUST be >= 0
* *confidence*: Normalized to [0, 1] range regardless of provider
scale
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6.2.1.2. Segments Array
"segments": [
{
"id": "integer", // Sequential segment identifier
"start": "number", // Start time in seconds
"end": "number", // End time in seconds
"text": "string", // Segment text content
"confidence": "number", // Segment-level confidence \[0.0-1.0\]
"speaker": "integer|string", // Optional: Speaker identifier
"words": ["integer"] // Optional: Array of word indices
}
]
Segments represent logical chunks of transcribed content, typically
sentence or phrase boundaries:
* *id*: MUST be unique within the document, typically sequential
* *start*/*end*: Floating-point seconds, where end > start
* *text*: SHOULD be trimmed of leading/trailing whitespace
* *speaker*: Can be integer (0, 1, 2) or string ("Speaker A")
* *words*: References indices in the words array
6.2.1.3. Metadata Object
"metadata": {
"created_at": "string", // ISO 8601 timestamp
"processed_at": "string", // ISO 8601 timestamp
"provider": "string", // Provider name (lowercase)
"model": "string", // Model/version identifier
"processing_time": "number", // Optional: Processing duration in seconds
"audio": {
"duration": "number", // Source audio duration in seconds
"sample_rate": "integer", // Optional: Sample rate in Hz
"channels": "integer", // Optional: Number of channels
"format": "string", // Optional: Audio format
"bitrate": "integer" // Optional: Bitrate in kbps
},
"options": "object" // Provider-specific options used
}
The metadata object captures processing and source information:
* *created_at*/*processed_at*: MUST use ISO 8601 format
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* *provider*: Lowercase identifier for supported providers
* *model*: Provider's model identifier (e.g., "whisper-large-v3",
"nova-2")
* *options*: Preserves provider-specific configuration
6.2.2. Optional Fields
6.2.2.1. Words Array
"words": [
{
"id": "integer", // Sequential word identifier
"start": "number", // Word start time in seconds
"end": "number", // Word end time in seconds
"text": "string", // Word text
"confidence": "number", // Word-level confidence \[0.0-1.0\]
"speaker": "integer|string", // Optional: Speaker identifier
"is_punctuation": "boolean" // Optional: Punctuation marker
}
]
6.2.2.2. Speakers Object
"speakers": {
"speaker_id": {
"id": "integer|string", // Speaker identifier
"label": "string", // Human-readable speaker name
"segments": ["integer"], // Array of segment IDs for this speaker
"total_time": "number", // Total speaking time in seconds
"confidence": "number" // Diarization confidence \[0.0-1.0\]
}
}
6.2.2.3. Quality Object
"quality": {
"audio_quality": "string", // high, medium, low
"background_noise": "number", // Noise level \[0.0-1.0\]
"multiple_speakers": "boolean",
"overlapping_speech": "boolean",
"silence_ratio": "number", // Percentage of silence
"average_confidence": "number",
"low_confidence_words": "integer",
"processing_warnings": ["string"]
}
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6.2.2.4. Extensions Object
"extensions": {
"provider_name": {
// Provider-specific fields preserved during conversion
}
}
7. Provider Integration Guidelines
7.1. Supported Providers
The WTF extension supports integration with major transcription
providers:
* *Whisper(TM)*: OpenAI's open-source speech recognition system
* *Deepgram(TM)*: Real-time speech-to-text API
* *AssemblyAI(TM)*: AI-powered transcription and audio intelligence
* *Google Cloud Speech-to-Text(TM)*: Google's speech recognition
service
* *Amazon Transcribe(TM)*: AWS speech-to-text service
* *Azure Speech Services(TM)*: Microsoft's speech recognition
platform
* *Rev.ai(TM)*: Automated and human transcription services
* *Speechmatics(TM)*: Real-time and batch speech recognition
* *Wav2Vec2(TM)*: Facebook's self-supervised speech recognition
model
* *Parakeet(TM)*: NVIDIA's speech recognition toolkit
7.2. Conversion Requirements
When converting from provider-specific formats to WTF:
1. *Normalize confidence scores* to [0.0, 1.0] range
2. *Convert timestamps* to floating-point seconds
3. *Standardize language codes* to BCP-47 format
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4. *Preserve provider-specific features* in extensions field
5. *Validate output* against WTF schema requirements
7.3. Provider-Specific Mappings
7.3.1. Whisper Integration
{
"extensions": {
"whisper": {
"tokens": ["array of token IDs"],
"temperature": "number",
"compression_ratio": "number",
"avg_logprob": "number",
"no_speech_prob": "number"
}
}
}
7.3.2. Deepgram Integration
{
"extensions": {
"deepgram": {
"utterances": ["array of utterance objects"],
"paragraphs": ["array of paragraph objects"],
"search_terms": ["array of detected search terms"]
}
}
}
8. Quality and Confidence Metrics
8.1. Confidence Score Normalization
All confidence scores MUST be normalized to the [0.0, 1.0] range:
* *1.0*: Highest confidence (perfect recognition)
* *0.9-1.0*: High confidence
* *0.7-0.9*: Medium confidence
* *0.5-0.7*: Low confidence
* *0.0-0.5*: Very low confidence
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Provider-specific scales are converted during import:
* Percentage (0-100) -> divide by 100
* Log probability -> exponential transformation
* Custom scales -> linear normalization
8.2. Quality Metrics
The quality object provides assessment metrics:
* *audio_quality*: Categorical assessment (high/medium/low)
* *background_noise*: Noise level [0.0-1.0]
* *multiple_speakers*: Boolean indicator of multi-speaker content
* *overlapping_speech*: Boolean indicator of speaker overlap
* *silence_ratio*: Percentage of audio that is silence
* *average_confidence*: Mean confidence across all words/segments
* *low_confidence_words*: Count of words below 0.5 confidence
* *processing_warnings*: Array of processing issues or notices
9. Security Considerations
9.1. Data Privacy
Transcription data often contains sensitive personal information.
Implementations SHOULD:
* Apply appropriate access controls to WTF analysis objects
* Consider encryption requirements for transcription data at rest
and in transit
* Implement data retention policies consistent with privacy
regulations
* Provide mechanisms for transcription data redaction or
anonymization
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9.2. Provider-Specific Security
When integrating with external transcription providers:
* Validate provider credentials and API security
* Implement secure communication channels (TLS 1.2 or higher)
* Consider data residency requirements for audio processing
* Audit provider data handling practices and compliance
certifications
9.3. Integrity Protection
WTF transcription analysis objects SHOULD be integrity protected
using vCon signing mechanisms as defined in
[I-D.draft-ietf-vcon-core-00] to prevent unauthorized modification of
transcription data.
9.4. Temporal Validation
Implementations SHOULD validate that transcription timestamps are
consistent with the associated dialog timing information to detect
potential tampering or synchronization issues.
10. WTF as an Analysis Framework
The World Transcription Format is fundamentally an *analysis
framework* that defines how speech-to-text transcription results
should be structured, validated, and stored within vCon containers.
This section clarifies the distinction between WTF as an analysis
type and its storage mechanism.
10.1. Analysis vs. Storage
*WTF defines an analysis type*: The core contribution of this
specification is the definition of a standardized analysis framework
for transcription data. This includes:
* Structured representation of transcription content (words,
segments, complete transcripts)
* Quality assessment metrics (confidence scores, audio quality
indicators)
* Speaker diarization analysis
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* Provider-specific analytical features
* Processing metadata and provenance information
*Attachments provide storage*: The vCon analysis mechanism is used as
the storage container for WTF analysis results. The analysis type
"wtf_transcription" identifies the stored data as conforming to the
WTF analysis schema.
10.2. Analysis Processing Workflow
The typical workflow for WTF transcription analysis is:
1. *Audio Processing*: Dialog audio is processed by a transcription
provider
2. *Analysis Generation*: Provider results are converted to WTF
analysis schema
3. *Quality Assessment*: Analysis includes confidence scores and
quality metrics
4. *Storage*: WTF analysis is stored as a vCon attachment with type
"wtf_transcription"
5. *Retrieval*: Consumers read the attachment to access
transcription analysis results
6. *Utilization*: Analysis data is used for search, compliance,
accessibility, or further processing
11. IANA Considerations
11.1. vCon Extensions Names Registry
This document requests IANA to register the following extension in
the vCon Extensions Names Registry established by
[I-D.draft-ietf-vcon-core-00]:
* *Extension Name*: wtf_transcription
* *Extension Description*: World Transcription Format - A
standardized analysis framework for speech-to-text transcription
with multi-provider support, quality metrics, and confidence
scoring
* *Change Controller*: IESG
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* *Specification Document*: This document
11.2. WTF Analysis Type Values Registry
This document requests IANA to establish a new registry for WTF
analysis type values with the following initial registration:
* *Type Value*: wtf_transcription
* *Description*: Structured speech-to-text transcription analysis
using the World Transcription Format framework, including
transcription content, quality metrics, confidence scoring, and
provider-specific analytical features
* *Change Controller*: IESG
* *Specification Document*: This document
Registration Template: *Type Value*: The string value used as the
analysis type identifier in vCon attachments *Description*: Brief
description of the analysis type and its analytical capabilities
*Change Controller*: For Standards Track RFCs, list "IESG". For
others, give the name of the responsible party. *Specification
Document(s)*: Reference to defining documents with URIs where
available
11.3. WTF Provider Registry
This document requests IANA to establish a new registry for WTF
transcription analysis providers with initial registrations for
supported providers:
* *Provider Name*: whisper
* *Description*: OpenAI Whisper(TM) speech recognition system
* *Change Controller*: IESG
* *Specification Document*: This document (Additional provider
registrations would be added for each supported provider)
12. Examples
12.1. Basic Two-Party Call Transcription Analysis
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{
"uuid": "01928e10-193e-8231-b9a2-279e0d16bc46",
"vcon": "0.0.2",
"extensions": ["wtf_transcription"],
"created_at": "2025-01-02T12:00:00Z",
"parties": [
{
"tel": "+1-555-123-4567",
"name": "Alice"
},
{
"tel": "+1-555-987-6543",
"name": "Bob"
}
],
"dialog": [
{
"type": "recording",
"start": "2025-01-02T12:15:30Z",
"duration": 65.2,
"parties": [0, 1],
"mediatype": "audio/wav",
"filename": "call-recording.wav"
}
],
"analysis": [
{
"type": "wtf_transcription",
"start": "2025-01-02T12:16:35Z",
"dialog": 0,
"encoding": "json",
"body": {
"transcript": {
"text": "Hello, this is Alice from customer service. " +
"How can I help you today? Hi Alice, I'm having " +
"trouble with my account. Can you help me reset " +
"my password?",
"language": "en-US",
"duration": 65.2,
"confidence": 0.92
},
"segments": [
{
"id": 0,
"start": 0.5,
"end": 4.8,
"text": "Hello, this is Alice from customer service. " +
"How can I help you today?",
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"confidence": 0.95,
"speaker": 0,
"words": [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14]
},
{
"id": 1,
"start": 5.2,
"end": 9.1,
"text": "Hi Alice, I'm having trouble with my account. " +
"Can you help me reset my password?",
"confidence": 0.88,
"speaker": 1,
"words": [16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29,
30, 31]
}
],
"words": [
{
"id": 0,
"start": 0.5,
"end": 0.8,
"text": "Hello",
"confidence": 0.98,
"speaker": 0,
"is_punctuation": false
},
{
"id": 1,
"start": 0.9,
"end": 1.1,
"text": ",",
"confidence": 0.95,
"speaker": 0,
"is_punctuation": true
}
// Additional words...
],
"speakers": {
"0": {
"id": 0,
"label": "Alice (Customer Service)",
"segments": [0],
"total_time": 4.3,
"confidence": 0.95
},
"1": {
"id": 1,
"label": "Bob (Customer)",
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"segments": [1],
"total_time": 3.9,
"confidence": 0.88
}
},
"metadata": {
"created_at": "2025-01-02T12:15:30Z",
"processed_at": "2025-01-02T12:16:35Z",
"provider": "deepgram",
"model": "nova-2",
"processing_time": 12.5,
"audio": {
"duration": 65.2,
"sample_rate": 8000,
"channels": 1,
"format": "wav",
"bitrate": 128
},
"options": {
"punctuate": true,
"diarize": true,
"language": "en"
}
},
"quality": {
"audio_quality": "high",
"background_noise": 0.1,
"multiple_speakers": true,
"overlapping_speech": false,
"silence_ratio": 0.15,
"average_confidence": 0.92,
"low_confidence_words": 0,
"processing_warnings": []
},
"extensions": {
"deepgram": {
"utterances": [
{
"start": 0.5,
"end": 4.8,
"confidence": 0.95,
"channel": 0,
"transcript": "Hello, this is Alice from customer service. " +
"How can I help you today?"
}
]
}
}
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}
}
]
}
12.2. Multi-Provider Transcription Analysis Comparison
{
"analysis": [
{
"type": "wtf_transcription",
"dialog": 0,
"encoding": "json",
"body": {
"transcript": {
"text": "The quick brown fox jumps over the lazy dog.",
"language": "en-US",
"duration": 3.5,
"confidence": 0.96
},
"segments": [
{
"id": 0,
"start": 0.0,
"end": 3.5,
"text": "The quick brown fox jumps over the lazy dog.",
"confidence": 0.96,
"speaker": 0
}
],
"metadata": {
"created_at": "2025-01-02T12:00:00Z",
"processed_at": "2025-01-02T12:00:15Z",
"provider": "whisper",
"model": "whisper-large-v3",
"processing_time": 15.2
},
"extensions": {
"whisper": {
"temperature": 0.0,
"compression_ratio": 2.1,
"avg_logprob": -0.25,
"no_speech_prob": 0.01
}
}
}
},
{
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"type": "wtf_transcription",
"dialog": 0,
"encoding": "json",
"body": {
"transcript": {
"text": "The quick brown fox jumps over the lazy dog.",
"language": "en-US",
"duration": 3.5,
"confidence": 0.94
},
"segments": [
{
"id": 0,
"start": 0.0,
"end": 3.5,
"text": "The quick brown fox jumps over the lazy dog.",
"confidence": 0.94,
"speaker": 0
}
],
"metadata": {
"created_at": "2025-01-02T12:00:00Z",
"processed_at": "2025-01-02T12:00:08Z",
"provider": "deepgram",
"model": "nova-2",
"processing_time": 8.1
},
"extensions": {
"deepgram": {
"model_info": {
"name": "nova-2",
"version": "2024-01-09",
"uuid": "4d892fb6-7cc1-4e7a-a1b3-1c2e3f4a5b6c"
}
}
}
}
}
]
}
13. References
13.1. Normative References
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[I-D.draft-ietf-vcon-core-00]
Petrie, D., "Virtualized Conversation (vCon) Container",
Work in Progress, Internet-Draft, draft-ietf-vcon-core-00,
March 2025, <I-D.draft-ietf-vcon-core-00>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/rfc/rfc2119>.
[RFC3339] Klyne, G., "Date and Time on the Internet: Timestamps",
July 2002, <https://www.rfc-editor.org/rfc/rfc3339.html>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/rfc/rfc8174>.
[RFC8949] Bormann, C., "Concise Binary Object Representation
(CBOR)", December 2020,
<https://www.rfc-editor.org/rfc/rfc8949.html>.
13.2. Informative References
[BCP47] Phillips, A., "Tags for Identifying Languages", September
2009, <https://www.rfc-editor.org/rfc/rfc5646.html>.
[I-D.draft-ietf-vcon-overview]
McCarthy-Howe, T., "The vCon - Conversation Data Container
- Overview", Work in Progress, Internet-Draft, draft-ietf-
vcon-overview-00, July 2025, <I-D.draft-ietf-vcon-
overview-00>.
[WHISPER] Radford, A., Kim, J. W., Xu, T., Brockman, G., McLeavey,
C., and I. Sutskever, "Whisper: Robust Speech Recognition
via Large-Scale Weak Supervision", September 2022,
<https://openai.com/research/whisper>.
Acknowledgements
* Appreciation to the transcription provider community for their
input on standardization requirements and analysis framework
design.
* Thanks to the vCon working group for their feedback and guidance
on extension design patterns and the distinction between analysis
types and attachment mechanisms.
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Trademark Notice
All trademarks mentioned in this document are the property of their
respective owners. The use of these trademarks does not imply
endorsement by the IETF or the authors of this document. The
following trademarks are referenced:
* Whisper(TM) is a trademark of OpenAI, Inc.
* Deepgram(TM) is a trademark of Deepgram, Inc.
* AssemblyAI(TM) is a trademark of AssemblyAI, Inc.
* Google Cloud Speech-to-Text(TM) is a trademark of Google LLC.
* Amazon Transcribe(TM) is a trademark of Amazon.com, Inc.
* Azure Speech Services(TM) is a trademark of Microsoft Corporation.
* Rev.ai(TM) is a trademark of Rev.com, Inc.
* Speechmatics(TM) is a trademark of Speechmatics Limited.
* Wav2Vec2(TM) is a trademark of Meta Platforms, Inc.
* Parakeet(TM) is a trademark of NVIDIA Corporation.
Author's Address
Thomas McCarthy-Howe
VCONIC
Email: ghostofbasho@gmail.com
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