Advanced Parameter Transcription

TODO (Screenshot Replacement): Advanced parameter panel (App 2.0) Include: Prompt, Beam Search, no-speech threshold, temperature, max context, and reset/apply controls. Suggested filename: advanced-params-v2-en.png

Scope

Advanced parameters tune Whisper decoding behavior. They do not change business workflows such as link downloading or watch scheduling.

Key controls include:

• Suppress non-speech tokens
• Prompt
• Decoding strategy (Greedy / Beam Search)
• Maximum context
• No-speech threshold
• Length limit
• Entropy threshold
• Log probability threshold
• Temperature

Use Cases

• Hallucination or repetitive output in noisy audio
• Domain-heavy vocabulary with unstable recognition
• Long-form audio with coherence issues
• High-accuracy review pipelines

Steps

1. Open advanced parameters in transcription settings or task dialog.
2. Run a baseline with defaults.
3. Change only 1–2 parameters per test iteration.
4. Track parameter/result pairs for reusable team presets.
5. For realtime tasks, start with realtime presets before copying offline values.

Quick tuning tips

• Hallucination: increase no-speech threshold, lower temperature, reduce max context
• Terminology misses: add prompt terms and test Beam Search
• Incomplete output: carefully lower log probability threshold

Term Explanations

• Prompt: vocabulary/context hint for recognition, not a generic LLM command.
• No-speech threshold: controls how aggressively silence/background is filtered.
• Log probability threshold: confidence cutoff that affects truncation vs noise tolerance.

Real Scenario: Terminology-heavy Technical Recording

1. Run a default baseline and mark high-error segments.
2. Add domain terms into Prompt, then tune Beam Search only.
3. If hallucination persists, adjust no-speech threshold and temperature.
4. Change only 1–2 parameters per round and log outcomes for rollback.

This controlled iteration model is usually more reliable than bulk-changing all knobs at once.

Common Mistakes

• Mistake 1: Expecting advanced params to replace model selection.
  Fix: choose the right model tier first, then tune decoding behavior.
• Mistake 2: Editing too many parameters in one pass.
  Fix: isolate variables to understand real impact.
• Mistake 3: Copying offline presets directly to realtime workloads.
  Fix: start with realtime-safe presets and tune for latency constraints.

FAQ

Q: Is Beam Search always better than Greedy?
A: Not always. Beam Search often improves stability but costs more latency.

Q: Can Prompt enforce output format like an LLM instruction?
A: No. Whisper prompts are contextual hints, not general instruction control.

Q: Why do results differ across machines with same settings?
A: Hardware, drivers, runtime backends, and resource pressure all influence outcomes.

Limitations

• Parameter behavior is language- and noise-dependent.
• Some advanced controls may be restricted by entitlement/version.
• Extreme values can cause empty output, instability, or severe latency.
• Platform: Advanced params are available on both Windows/macOS, but backend differences can change same-setting outcomes.