Create audiobooks from text files

• This program is written in Python and is using UnrealSpeech under the hood for TTS.
• Check out an audio sample of a paragraph to see the quality of audio.

What does it do?

• Converts text files into OGG audiobook.
• Bakes metatags and cover image to OGG file.
• Has a really awesome reading voice provided by UnrealSpeech.

Installation

Program uses virtual environments so make sure that you have Python, Pip and virtual environments installed properly.

On macOS you will need brew.sh installed.

• SoX - Sound eXchange
  • On Debian-like systems - sudo apt install sox
  • On macOS - brew install sox
• Vorbis tools
  • On Debian-like systems - sudo apt install vorbis-tools
  • On macOS - brew install vorbis-tools
• Then follow instructions below.

git clone git@github.com:mitjafelicijan/abtts.git
cd abtts

python3 -m venv .venv
source .venv/bin/activate
pip install -r requirements.txt

How to use it

Creating audiobooks is a two step process. First you prepare an audiobook and then you export it.

Pre-requirements:

• First you need to create UnrealSpeech account.
• Create an API Token and store it somewhere safe. You will need it for this.
• Generate first book that is provided with this repository. Use the API token in US_BEARER environment variable like in example below.
• Be sure you are in Python virtual environment.

To see all the options you can do python abtts.py --help.

This example book was taken from Standard Ebooks. They have an amazing assortment of books. You should definitely check them out. All of their material is available on GitHub as well.

Preparing audiobook

• This will parse TOC file and call TTS API and generate a bunch of WAV files for each paragraphs from the book in the out directory (provided you didn't mess with OUT_DIR variable). Mind the --prepare flag.
• A JSON report file will also be generated in the out directory for you so you can see if all went well.
• If by any chance this fails for a paragraph with 500 code you can execute the command again and it will skip already existing and generated paragraphs. Sometimes UnrealSpeech API can behave badly so don't worry about it and just re-run the script.

US_BEARER="CW5RhoOX..." python3 abtts.py --book=books/armageddon-2419/ --prepare

Exporting audiobook

• This is a simpler process which combines all the WAV files that were outcome from prepare procedure and generates one WAV file.
• Then encoding happens where this WAV file is encoded to OGG file. This may take some time. These files can get gigabytes in size. Be patient.
• After that metatags and book cover are embedded in OGG file.
• Mind the --export flag.

US_BEARER="CW5RhoOX..." python3 abtts.py --book=books/armageddon-2419/ --export

Environmental variables

Environmental variables can prefix python command like in the example above with US_BEARER.

Variable	Default value	Description
TMP_DIR	tmp/	Paragraph WAV's files are put here
OUT_DIR	out/	Final audiobook location
US_BEARER	None	Bearer token for UnrealSpeech
US_VOICE_ID	male-4	Selected voice ID (male-0..male-4)
START_END_SILENCE	2000	How many seconds get added at beginning and end

Create new audiobooks

• Books have a specific filesystem structure. Each book needs to have toc.txt file and cover image in the same directory.
• Each book should have it's own directory to itself. Do not mix and match multiple books together.
• Books should be split into chapters, but also only one chapter is sufficient.

And example of a TOC file (toc.txt).

-- title: Armageddon 2419 A.D.
-- author: Philip Francis Nowlan
-- year: 1929
-- cover: cover.jpg
-- words: 27337
-- length: 1 hour 40 minutes

# foreword.txt

chapter1.txt
chapter2.txt
chapter3.txt
chapter4.txt

• Chapter files like chapter1.txt must be all in the same folder as toc.txt.
• You can comment lines if you want with #. These files will be omitted.
• Lines starting with -- are special meta tags and ( author, year, cover, words, length) are all required. They can be empty, but they must be provided.
• Title (title) tag must not be empty. Filenames get generated from this value so make sure this tag is populated.
• Cover images are baked into the OGG file. Cover image MUST be a JPEG.

Included books

• Armageddon 2419 A.D., Philip Francis Nowlan, 1929
• Flatland, Edwin A. Abbott, 1884
• The Airlords of Han, Philip Francis Nowlan, 1929
• The Strange Case of Dr. Jekyll and Mr. Hyde, Robert Louis Stevenson, 1886
• The Time Machine, H. G. Wells, 1895

Libraries used

• https://github.com/psf/requests
• https://github.com/quodlibet/mutagen
• https://github.com/un33k/python-slugify

License

abtts was written by Mitja Felicijan and is released under the BSD two-clause license, see the LICENSE file for more information.