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Feedback: speech-to-text-pre-recorded-audio-word-level-timestamps

Original URL: https://www.assemblyai.com/docs/speech-to-text/pre-recorded-audio/word-level-timestamps
Category: speech-to-text
Generated: 05/08/2025, 4:23:30 pm


Generated: 05/08/2025, 4:23:29 pm

Technical Documentation Analysis: Word-Level Timestamps

Section titled “Technical Documentation Analysis: Word-Level Timestamps”

This documentation demonstrates how to access word-level timestamps from speech-to-text transcriptions across multiple programming languages. While comprehensive in code examples, it has several areas for improvement in structure, clarity, and user guidance.

Critical Gaps:

  • No introduction or overview explaining what word-level timestamps are and their use cases
  • Missing configuration requirements - Does this feature need to be explicitly enabled?
  • No error handling guidance for when word data is unavailable
  • Pricing/limitations information - Are there additional costs or usage limits?
  • Audio format compatibility - Which formats support word-level timestamps?

Add this section at the beginning:

## Overview
Word-level timestamps provide precise start and end times for each word in your transcription, enabling:
- Synchronized subtitle generation
- Audio highlighting and navigation
- Precise content editing
- Accessibility features
This feature is automatically included with all transcriptions at no additional cost.

Issues:

  • Timestamp units unclear - The JSON shows values like 240, 640 but doesn’t specify these are milliseconds
  • Confidence score interpretation - What do values like 0.70473 mean in practice?
  • Speaker field explanation - Why is it null in examples?

Improvements needed:

## Understanding the Data
- **start/end**: Timestamps in milliseconds from audio beginning
- **confidence**: Accuracy score from 0.0-1.0 (0.8+ considered high confidence)
- **speaker**: Speaker identifier when Speaker Diarization is enabled, otherwise null

Current issues:

  • All examples use the same generic audio file
  • No real-world use case demonstrations
  • Missing example output formatting

Recommended additions:

# Example: Generate SRT subtitles
def create_srt_from_words(words, words_per_subtitle=8):
subtitles = []
for i in range(0, len(words), words_per_subtitle):
chunk = words[i:i+words_per_subtitle]
start_time = format_timestamp(chunk[0].start)
end_time = format_timestamp(chunk[-1].end)
text = ' '.join([word.text for word in chunk])
subtitles.append(f"{start_time} --> {end_time}\n{text}")
return subtitles
# Example: Filter low-confidence words
high_confidence_words = [
word for word in transcript.words
if word.confidence > 0.8
]

Current structure issues:

  • Code examples come before explanation
  • No logical flow from basic to advanced usage
  • Missing navigation aids

Recommended structure:

# Word-Level Timestamps
## Overview
[What it is and why use it]
## Quick Start
[Minimal working example]
## Understanding the Response
[Data structure explanation]
## Code Examples
[Multiple language examples]
## Common Use Cases
[Practical applications with code]
## Troubleshooting
[Common issues and solutions]
## API Reference
[Technical specifications]

Identified issues:

a) No activation guidance:

## Configuration
Word-level timestamps are automatically included in all transcription responses. No additional configuration required.
However, ensure your transcription request includes:
- Valid audio format (MP3, WAV, FLAC, etc.)
- Audio quality sufficient for word-level detection

b) Missing error scenarios:

# Handle missing word data
if hasattr(transcript, 'words') and transcript.words:
for word in transcript.words:
print(f"Word: {word.text}")
else:
print("Word-level data not available for this transcription")

c) No performance guidance:

## Best Practices
- **Large files**: Consider processing words in chunks to avoid memory issues
- **Real-time applications**: Buffer word data to prevent UI blocking
- **Storage**: Word arrays can be large; consider storing only essential fields

d) Inconsistent code patterns:

  • Some examples use different variable names
  • Error handling varies between languages
  • Missing imports in some examples

Add these sections:

Filtering and Processing:

## Working with Word Data
### Filter by confidence
### Group words by time ranges
### Export to common formats (SRT, VTT, JSON)

Integration Examples:

## Common Integrations
- Video player synchronization
- Search and highlight functionality
- Automated captioning systems

Troubleshooting Section:

## Troubleshooting
- **Empty words array**: Check audio quality and format compatibility
- **Inaccurate timestamps**: Verify audio encoding and sample rate
- **Missing confidence scores**: Normal for some audio types
  1. High Priority: Add overview section and timestamp unit clarification
  2. Medium Priority: Restructure content flow and add use case examples
  3. Low Priority: Add advanced filtering examples and troubleshooting guide

This documentation has good technical coverage but needs better user onboarding and practical guidance to reduce implementation friction.