Subtitle To Document

Subtitles to Document

Convert WebVTT (.vtt) and SubRip (.srt) subtitle files into clean, readable text documents with natural paragraph flow and multi-language support.

Supported Languages

• English (en) - Automatic capitalization, space-based word separation
• Traditional Chinese (zh_tw / \u7e41\u9ad4\u4e2d\u6587) - Chinese punctuation detection, no spaces between characters
• Simplified Chinese (zh_cn / \u7b80\u4f53\u4e2d\u6587) - Chinese punctuation detection, no spaces between characters

The script auto-detects the subtitle format (VTT or SRT) and the language by default.

Quick Start

Auto-detect Format and Language (Default)

When the user provides a subtitle file path, run the conversion script:

python scripts/subtitle_to_text.py input.vtt
# or
python scripts/subtitle_to_text.py input.srt

This creates input.txt in the same directory with cleaned, formatted text.

Specify Language or Format

# English
python scripts/subtitle_to_text.py input.srt --lang en

# Traditional Chinese
python scripts/subtitle_to_text.py input.vtt --lang zh_tw

# Force SRT parsing
python scripts/subtitle_to_text.py input.srt --format srt

Specify Custom Output Path

python scripts/subtitle_to_text.py input.srt output.txt --lang zh_tw

What the Script Does

The subtitle_to_text.py script automatically performs format- and language-aware processing:

All Formats

1. Removes timestamps - Strips VTT/SRT timing information (e.g., 00:00:00.000 --> 00:00:02.500 or 00:00:00,000 --> 00:00:02,500)
2. Removes subtitle formatting - Strips tags like <v Speaker>, <c>, <i>, etc.
3. Removes duplicates - Detects and removes consecutive duplicate captions

Language-Specific Processing

English (en)

• Sentence detection: ., !, ?
• Annotations removed: [Music], [Applause], [Laughter], [Inaudible]
• Capitalization: Auto-capitalizes sentences and fixes i -> I
• Spacing: Adds spaces between words, fixes punctuation spacing

Traditional Chinese (zh_tw)

• Sentence detection: \u3002, \uff01, \uff1f
• Annotations removed: [...] (Chinese and English annotations)
• Capitalization: Not applicable
• Spacing: Removes spaces between Chinese characters, preserves spacing around embedded English words

Simplified Chinese (zh_cn)

• Same behavior as Traditional Chinese, using simplified character indicators for detection

Format Detection

Format detection uses file extension (.vtt / .srt) and content heuristics (WEBVTT header, presence of --> timestamps). You can override detection with --format.

If auto-detection is incorrect, override with --format srt or --format vtt, or set --lang to force language.

Workflow

When a user requests subtitle conversion:

1. Confirm the input subtitle file path exists
2. Determine the format (auto-detect or ask user to override)
3. Determine language (auto-detect or ask user to override)
4. Run the script with appropriate flags if needed
5. Display a preview of the converted text
6. Confirm the output file location

Examples

Example 1: SRT (English)

Input SRT:

1
00:00:00,000 --> 00:00:02,500
Hello and welcome to this tutorial.

2
00:00:02,500 --> 00:00:05,000
Today we're going to learn

3
00:00:05,000 --> 00:00:07,500
about video text tracks.

Output Text:

Hello and welcome to this tutorial.

Today we're going to learn about video text tracks.

Example 2: VTT (Traditional Chinese)

Use --lang zh_tw or allow auto-detection.

Using from Python

The script can also be imported as a module:

from scripts.subtitle_to_text import convert_subtitles_to_text

# Auto-detect format & language
text = convert_subtitles_to_text('input.srt', 'output.txt')

# Specify language or format
text = convert_subtitles_to_text('input.vtt', 'output.txt', lang='zh_tw', fmt='vtt')

# Backwards-compatible alias
from scripts.subtitle_to_text import convert_vtt_to_text
text = convert_vtt_to_text('input.vtt', 'output.txt')

Troubleshooting

Wrong format detected: Use --format srt or --format vtt to override:

python scripts/subtitle_to_text.py input.srt --format srt

Wrong language detected: Use --lang to override:

python scripts/subtitle_to_text.py input.srt --lang zh_tw

Encoding errors: The script uses UTF-8 encoding by default. If the subtitle file uses a different encoding, convert it to UTF-8 first.

Missing paragraphs: The script merges based on language-specific sentence-ending punctuation. If captions lack proper punctuation they may merge into larger paragraphs.

Mixed language content: The script works best with single-language files. For mixed English/Chinese content consider processing separately.

CLI Reference

Usage: python subtitle_to_text.py <input.vtt|input.srt> [output.txt] [--lang en|zh_tw|zh_cn] [--format auto|vtt|srt]

Language options:
  --lang auto    Auto-detect language (default)
  --lang en      English
  --lang zh_tw   Traditional Chinese (\u7e41\u9ad4\u4e2d\u6587)
  --lang zh_cn   Simplified Chinese (\u7b80\u4f53\u4e2d\u6587)

Format options:
  --format auto  Auto-detect subtitle format (default)
  --format vtt   Force VTT parsing
  --format srt   Force SRT parsing

If output path is not specified, a .txt file will be created next to input.