Quick Example

Walk through processing a 14-minute TED talk from start to finish. See how VideoCaptioner handles transcription, optimization, translation, and synthesis.

Processing Pipeline

1Speech Transcription
2Intelligent Segmentation
3Translation & Optimization
4Video Synthesis
5Cost Review

Step 1: Speech Transcription

Using Faster Whisper Large-v2 model with Silero V4 VAD (Voice Activity Detection), the system generates initial subtitles from the audio track.

Terminal
videocaptioner transcribe ted-talk.mp4 --asr faster-whisper --model large-v2

The raw output has high recognition accuracy, but the sentence breaking is mechanical with basic punctuation — this is normal for raw ASR output.

Step 2: Intelligent Enhancement

Enable smart segmentation, optimization, and translation. The LLM performs semantic-based segmentation, producing fluid natural-language subtitles.

Terminal
videocaptioner subtitle ted-talk.srt \
  --optimizer llm \
  --translator llm \
  --target-language zh \
  --enable-reflection

Reflection Translation

The system uses a two-pass "translate-reflect-translate" approach for each subtitle:

  • Removes redundant words for conciseness
  • Naturalizes expressions to sound native
  • Compacts phrasing while preserving meaning
  • Optimizes verb selection and word order

Step 3: Video Synthesis

Burn the optimized subtitles into the video with a professional dual-language layout:

Terminal
videocaptioner synthesize ted-talk.mp4 -s ted-talk_optimized.srt

Step 4: All-in-One Command

Or simply run the entire pipeline with a single command:

Terminal
videocaptioner process ted-talk.mp4 --target-language zh

Performance

StageDuration
Transcription~2 min
Segmentation~30 sec
Translation~1 min
Synthesis~30 sec
Total~4 min

Cost Analysis

Incredibly affordable

For a 14-minute video with ~50 subtitle segments using gpt-4o-mini: approximately 5,000 tokens consumed, total cost < $0.002. The LLM only processes text (no timeline data), so token usage is minimal.

Ideal Use Cases

  • Educational content — Create bilingual learning materials
  • Content creators — Multi-language versions for global reach
  • Business — Video localization for international markets
  • Conferences — Documentation with accurate subtitles