eprec

eprec

Tools for processing Epic Web course recordings

Overview

A Bun-based CLI that processes recorded course videos by splitting chapter markers into separate files, trimming silence at the start/end, and optionally removing spoken "Jarvis" command windows via transcript timestamps refined with audio-based silence detection.

Requirements

• Bun - runtime and package manager
• ffmpeg + ffprobe - must be available on PATH
• whisper-cli (optional) - from whisper.cpp, required for transcription
  • Pass --whisper-binary-path if not on PATH
  • Model file auto-downloads to .cache/whispercpp/ggml-small.en.bin
• Silero VAD model - auto-downloads to .cache/silero-vad.onnx on first use

Installation

bun install

Quick Start

bun src/process-course-video.ts "/path/to/input.mp4" "/path/to/output" \
  --enable-transcription \
  --keep-intermediates \
  --write-logs

Web UI (experimental)

Start the Remix-powered UI shell (watch mode enabled):

bun run app:start

To preload a local video path for the UI:

bun run app:start -- --video-path "/path/to/video.mp4"

Then open http://localhost:3000. Use -- --port, -- --host, or -- --video-path to override the defaults.

CLI Options

Option	Alias	Description	Default
input		Input video file (mp4/mkv)	required
outputDir		Output directory	output
--min-chapter-seconds	-m	Skip chapters shorter than this	15
--dry-run	-d	Don't write files or run ffmpeg	false
--keep-intermediates	-k	Keep .tmp files for debugging	false
--write-logs	-l	Write log files for skips/fallbacks	false
--enable-transcription		Run whisper.cpp for command detection	false
--whisper-model-path		Path to whisper.cpp model file	auto-cached
--whisper-language		Language for whisper	en
--whisper-binary-path		Path to whisper-cli binary	system PATH
--chapter	-c	Filter to specific chapters (see below)	all

Chapter Selection

The --chapter flag supports flexible selection:

• Single: --chapter 4
• Range: --chapter 4-6
• Open range: --chapter 4-* (chapter 4 to end)
• Multiple: --chapter 4,6,9-12

Chapter numbers are 1-based by default.

Output Structure

Final files are written to the output directory with names like:

chapter-01-intro.mp4
chapter-02-getting-started.mp4
chapter-03-custom-title.mp4

When --keep-intermediates is enabled, intermediate files go to output/.tmp/:

File Pattern	Description
*-raw.mp4	Raw chapter clip with initial padding removed
*-normalized.mp4	Audio normalized (highpass + denoise + loudnorm)
*-transcribe.wav	Audio extracted for whisper
*-transcribe.json	Whisper JSON output
*-transcribe.txt	Whisper text output
*-splice-*.mp4	Segments before/after command windows
*-spliced.mp4	Concatenated output after command removal
*.log	Per-chapter skip/fallback logs
process-summary.log	Overall processing summary

Voice Commands

Commands are spoken in the format: jarvis <command> ... thanks

Command	Effect
jarvis bad take thanks	Skip the entire chapter
jarvis filename my-custom-name thanks	Rename output file

The command window (from "jarvis" to "thanks") is removed from the final video.

More Details

Implementation notes and pipeline details live in docs/README.md.

This project was created using bun init in bun v1.3.1. Bun is a fast all-in-one JavaScript runtime.