Architecture

Overview

                        CLI / REST API
                             |
                    +--------v--------+
                    |   Task System   |
                    | (PromptManager, |
                    |  TaskRegistry)  |
                    +--------+--------+
                             |
              +--------------+--------------+
              |                             |
     +--------v--------+          +--------v--------+
     |   Direct TTS    |          |   LLM Pipeline  |
     | (EpubSynth,     |          | (AudiobookCreator|
     |  PdfSynth)      |          |  + LLMClient)   |
     +--------+--------+          +--------+--------+
              |                             |
              |                    +--------v--------+
              |                    |  LLM Providers  |
              |                    | Ollama | Cloud   |
              |                    +-----------------+
              |                             |
              +-------------+---------------+
                            |
                   +--------v--------+
                   |  TTS Providers  |
                   | Kokoro | OpenAI |
                   | AWS    | Google |
                   | Qwen             |
                   +--------+--------+
                            |
                   +--------v--------+
                   | Audio Assembly  |
                   | (M4B builder,  |
                   |  AudioProcessor)|
                   +-----------------+

Pipeline

CLI -> Creator -> Synthesizer -> Reader

Readers (audify/readers/)

Extract text from source files:

• EpubReader – EPUB with chapter detection

• PdfReader – PDF documents

• TextReader – Plain text / Markdown

Abstract interface: audify/domain/reader.py

Task System (audify/prompts/)

• PromptManager – Loads built-in and custom prompts

• TaskRegistry – Maps task names to TaskConfig (prompt + LLM params)

• Built-in prompts stored as text files in audify/prompts/builtin/

AudiobookCreator (audify/audiobook_creator.py)

Orchestrates LLM script generation:

• LLMClient – Routes to Ollama or commercial APIs (via LiteLLM)

  • generate_script() – Accepts any prompt + LLM params

  • generate_audiobook_script() – Backward-compatible wrapper

• AudiobookCreator – Base class for LLM-powered audiobook creation

• AudiobookEpubCreator / AudiobookPdfCreator – Format-specific subclasses

• DirectoryAudiobookCreator – Multi-file processing

Synthesizers (audify/text_to_speech.py)

Convert text to speech via TTS providers:

• BaseSynthesizer – Manages TTS config, sentence splitting, WAV/MP3 conversion

• EpubSynthesizer / PdfSynthesizer – Direct TTS (no LLM)

• VoiceSamplesSynthesizer – Voice comparison tool

Audio Processing (audify/utils/)

• audio.py – Combines audio, format conversion

• m4b_builder.py – FFmpeg metadata, chapter markers, M4B assembly

External Services

Configured via docker-compose.yml:

• Kokoro TTS – Port 8887 (GPU)

• Ollama LLM – Port 11434 (GPU)

Commercial APIs (no Docker needed):

• LLM: DeepSeek, Claude, GPT-4, Gemini (via LiteLLM)

• TTS: OpenAI, AWS Polly, Google Cloud TTS