Ninja Listening Trainer by kouichicnakamura

Ninja Listening Trainer is a specialized browser extension designed to bridge the gap between textbook pronunciation and natural, real-world spoken language. Whether you are practicing shadowing, analyzing fast native speech, or conducting acoustic perception research, this tool gives you precise control over media playback and step-by-step training sequences.

• Instant Marking: Set precise Start and End points on any YouTube video or direct local audio file with millisecond accuracy.
• Custom Step Sequences: Seamlessly iterate through dynamic playback speed programs—from slow anchor speeds ($0.6\times$) up to time-compressed challenge speeds ($2.0\times$).
• Automatic Subtitle Sync: Toggle captions on or off automatically per step to force acoustic listening before relying on textual support.

• Optional VAS (Visual Analogue Scale) Ratings: Turn on Research Mode to assess your acoustic and phonological perception clarity at each step.
• Phonetic-Level Feedback: Measure how clearly you perceive individual sounds, phonemes, and syllables—not just general word boundaries.
• One-Click Data Export: Save your session ratings, timestamps, and playback configs into clean CSV or JSON files for statistical analysis (ANOVA, Pandas, R) or study logging.

• Built-in Experimental Protocols: Instant 1-click access to the Ninja Protocol ($0.6\times$ Anchor $\rightarrow 2.0\times$), Pure Compression, and Static Control modes.
• Load Custom Configs: Import/export standardized lesson files (.json) to share study protocols with students, study groups, or experiment participants.
• Local Media Support: Works natively on YouTube (youtube.com/watch) as well as local audio and video files opened directly in Firefox.

1. Mark Your Target: Navigate to a video/audio segment and click Mark start and Mark end.
2. Choose Your Preset: Select the Ninja Protocol or load a custom step configuration.
3. Run Sequence: Click ▶ Run sequence to begin your step-by-step listening practice.
4. (Optional) Check Collect VAS Ratings in the controls panel if you want to record perceptual clarity scores after each iteration and export your dataset.

Designed for language learners, English Speaking Society (ESS) practice, shadowing enthusiasts, and speech perception research.