# One settings file for the whole pipeline. Relative paths are relative to the repo root.

books_dir: books            # where book folders live: books/<first-author>/<book>/
work_dir: /tmp/audiobook-work   # scratch only (OCR output, wav pieces). Point at local NVMe in production.

# Where finished audio goes. Empty = the book folder in the repo (the agreed default).
# Set to a folder to write <archive_dir>/<first-author>/<book>/audio there instead.
archive_dir: ""

narrator: ""                # spoken in the credits only if filled in (leave empty for a TTS voice)

# Inserted parts. All OFF by default. Per-book and per-chapter switches in book.json override these.
summaries:
  chapter_preview: false
  chapter_summary: false
  concept_summary: false     # one mid-chapter concept summary

# OpenAI-compatible chat endpoint, used only when a summary switch is on.
llm:
  endpoint: ""               # e.g. http://host:8081/v1/chat/completions
  model: ""
  api_key_env: ""            # name of an environment variable that holds the key (never put a key here)
  timeout_s: 300

# OpenAI-compatible speech endpoint.
voice:
  endpoint: http://127.0.0.1:8000/v1/audio/speech
  model: chatterbox
  voice: default
  extra: {}                  # extra JSON fields sent with every request (for example speed)
  timeout_s: 600
  max_chunk_chars: 300       # long paragraphs are cut at sentence ends into pieces this size or smaller
  gap_sentence_s: 0.25       # pause between pieces inside a paragraph
  gap_paragraph_s: 0.7       # pause between paragraphs and after cues and labels

ocr:
  enabled: true              # run ocrmypdf only when a page has no text layer
  language: eng
  min_chars_per_page: 10     # fewer characters than this = no text layer

script:
  retail_sample_words: 400   # about 2.5 minutes at 155 words per minute (ACX asks for 1 to 5 minutes)
  chime_label: Chime

license:
  public_domain_max_year: 1930   # US, as of 2026

audio:
  sample_rate: 44100
  channels: 1
  mp3_bitrate: 192k
  head_room_tone_s: 0.75     # ACX 0.5 to 1
  tail_room_tone_s: 2.0      # ACX 1 to 5
  room_tone_db: -66          # RMS level of the room tone (ACX noise floor limit is -60)
  target_rms_db: -20.5       # ACX -23 to -18
  peak_ceiling_db: -4.0      # limiter ceiling; ACX limit is -3 and MP3 encoding can add a little
  chime_hz: 660
  chime_s: 1.0
  chime_db: -18              # peak level of the chime in the final file, kept soft

acx:                          # limits used by the checker (R13)
  min_bitrate_kbps: 192
  sample_rate: 44100
  rms_min_db: -23
  rms_max_db: -18
  peak_max_db: -3
  noise_floor_max_db: -60
  head_min_s: 0.5
  head_max_s: 1.0
  tail_min_s: 1.0
  tail_max_s: 5.0
  max_minutes: 120
  retail_min_s: 60
  retail_max_s: 300
  speech_window_db: -50      # a 50 ms window louder than this counts as speech when measuring head and tail