yihong0618/bilingual_book_maker

中文 | English

bilingual_book_maker

The bilingual_book_maker is an AI translation tool that uses ChatGPT to assist users in creating multi-language versions of epub/txt/md/srt/pdf files and books. This tool is exclusively designed for translating epub and other public domain works and is not intended for copyrighted works. Before using this tool, please review the project's disclaimer.

Supported Models

gpt-5-mini, gpt-4, gpt-3.5-turbo, claude-2, palm, llama-2, azure-openai, command-nightly, gemini, qwen-mt-turbo, qwen-mt-plus For using Non-OpenAI models, use class liteLLM() - liteLLM supports all models above. Find more info here for using liteLLM: https://github.com/BerriAI/litellm/blob/main/setup.py

Preparation

1. ChatGPT or OpenAI token ¹
2. epub/txt/md/pdf books
3. Environment with internet access or proxy
4. Python 3.8+

Quick Start

A sample book, test_books/animal_farm.epub, is provided for testing purposes.

pip install -r requirements.txt
python3 make_book.py --book_name test_books/animal_farm.epub --openai_key ${openai_key} --test
OR
pip install -U bbook_maker
bbook --book_name test_books/animal_farm.epub --openai_key ${openai_key} --test

Translate Service

• Use --openai_key option to specify OpenAI API key. If you have multiple keys, separate them by commas (xxx,xxx,xxx) to reduce errors caused by API call limits. Or, just set environment variable BBM_OPENAI_API_KEY instead.
• A sample book, test_books/animal_farm.epub, is provided for testing purposes.
• The default underlying model is GPT-3.5-turbo, which is used by ChatGPT currently. Use --model gpt4 to change the underlying model to GPT4. You can also use GPT4omini.
• Important to note that gpt-4 is significantly more expensive than gpt-4-turbo, but to avoid bumping into rate limits, we automatically balance queries across gpt-4-1106-preview, gpt-4, gpt-4-32k, gpt-4-0613,gpt-4-32k-0613.
• If you want to use a specific model alias with OpenAI (eg gpt-4-1106-preview or gpt-3.5-turbo-0125), you can use --model openai --model_list gpt-4-1106-preview,gpt-3.5-turbo-0125. --model_list takes a comma-separated list of model aliases.
• If using chatgptapi, you can add --use_context to add a context paragraph to each passage sent to the model for translation (see below).

• DeepL Support DeepL model DeepL Translator need pay to get the token

  python3 make_book.py --book_name test_books/animal_farm.epub --model deepl --deepl_key ${deepl_key}
  

• DeepL free

  python3 make_book.py --book_name test_books/animal_farm.epub --model deeplfree
  

• Claude

  Use Claude model to translate

  python3 make_book.py --book_name test_books/animal_farm.epub --model claude --claude_key ${claude_key}
  

• Google Translate

  python3 make_book.py --book_name test_books/animal_farm.epub --model google
  

• Caiyun Translate

  python3 make_book.py --book_name test_books/animal_farm.epub --model caiyun --caiyun_key ${caiyun_key}
  

• Gemini

  Support Google Gemini model, use --model gemini for Gemini Flash or --model geminipro for Gemini Pro. If you want to use a specific model alias with Gemini (eg gemini-2.5-flash or gemini-2.0-flash), you can use --model gemini --model_list gemini-2.5-flash,gemini-2.0-flash. --model_list takes a comma-separated list of model aliases.

  python3 make_book.py --book_name test_books/animal_farm.epub --model gemini --gemini_key ${gemini_key}
  

• Qwen

  Support Alibaba Cloud Qwen-MT specialized translation model. Supports 92 languages with features like terminology intervention and translation memory. Use --model qwen-mt-turbo for faster/cheaper translation, or --model qwen-mt-plus for higher quality.

  Use source_lang to specify the source language explicitly, or leave it empty for auto-detection.

  python3 make_book.py --book_name test_books/animal_farm.epub --qwen_key ${qwen_key} --model qwen-mt-turbo --language "Simplified Chinese"
  python3 make_book.py --book_name test_books/animal_farm.epub --qwen_key ${qwen_key} --model qwen-mt-plus --language "Japanese" --source_lang "English"
  

• Tencent TranSmart

  python3 make_book.py --book_name test_books/animal_farm.epub --model tencentransmart
  

• xAI

  python3 make_book.py --book_name test_books/animal_farm.epub --model xai --xai_key ${xai_key}
  

• Ollama

  Support Ollama self-host models, If ollama server is not running on localhost, use --api_base http://x.x.x.x:port/v1 to point to the ollama server address

  python3 make_book.py --book_name test_books/animal_farm.epub --ollama_model ${ollama_model_name}
  

• groq

  GroqCloud currently supports models: you can find from Supported Models

  python3 make_book.py --book_name test_books/animal_farm.epub --groq_key [your_key] --model groq --model_list llama3-8b-8192
  

• Custom API Provider

  If the built-in models don't cover your needs, you can define custom providers via a JSON config file. This lets you use any OpenAI-compatible API (DeepSeek, SiliconFlow, local proxies, etc.) without modifying source code.

  Create bbm_providers.json in the current directory (or ~/.bbm/providers.json for global config):

  {
    "providers": {
      "deepseek": {
        "api_style": "openai",
        "base_url": "https://api.deepseek.com/v1",
        "default_models": ["deepseek-chat", "deepseek-reasoner"],
        "env_key": "BBM_DEEPSEEK_API_KEY"
      },
      "siliconflow": {
        "api_style": "openai",
        "base_url": "https://api.siliconflow.cn/v1",
        "default_models": ["Qwen/Qwen2.5-72B-Instruct"],
        "env_key": "BBM_SILICONFLOW_API_KEY"
      }
    }
  }
  

  Config fields:

  Field	Required	Description
  api_style	Yes	Translator interface style. Supported: openai, claude, gemini, qwen
  base_url	No	API endpoint URL. Falls back to the api_style's default
  default_models	No	Default model list. Required if --model_list is not provided
  env_key	No	Environment variable name for API key. Required if --api_key is not provided

  Priority: project-level ./bbm_providers.json overrides global ~/.bbm/providers.json.

  --provider and --model are mutually exclusive.

  python3 make_book.py --provider deepseek --api_key sk-xxx --book_name test_books/animal_farm.epub
  
  export BBM_DEEPSEEK_API_KEY=sk-xxx
  python3 make_book.py --provider deepseek --book_name test_books/animal_farm.epub
  
  python3 make_book.py --provider deepseek --api_key sk-xxx --model_list deepseek-reasoner --book_name test_books/animal_farm.epub
  

Use

• Once the translation is complete, a bilingual book named ${book_name}_bilingual.epub would be generated for EPUB inputs; for TXT/MD/SRT inputs a bilingual text (or subtitle) file named ${book_name}_bilingual.txt (or _bilingual.srt) will be generated. For PDF inputs the tool will produce a bilingual .txt fallback and will also attempt to create ${book_name}_bilingual.epub — if EPUB creation fails, the TXT fallback remains so you do not need to retranslate.
• If there are any errors or you wish to interrupt the translation by pressing CTRL+C, a temporary bilingual file (for example {book_name}_bilingual_temp.epub or {book_name}_bilingual_temp.txt) would be generated. You can simply rename it to any desired name.

Params

• --model:

  Select the translation model. Default: chatgptapi. Available values and their behavior:

  Model	Key Source	Notes
  chatgptapi	--openai_key / BBM_OPENAI_API_KEY	GPT-3.5-turbo. Auto-detects available models from API
  gpt4	--openai_key / BBM_OPENAI_API_KEY	GPT-4 family. Auto-balances across available GPT-4 variants
  gpt4omini	--openai_key / BBM_OPENAI_API_KEY	GPT-4o-mini
  gpt4o	--openai_key / BBM_OPENAI_API_KEY	GPT-4o
  gpt5mini	--openai_key / BBM_OPENAI_API_KEY	GPT-5-mini
  o1preview	--openai_key / BBM_OPENAI_API_KEY	o1-preview
  o1	--openai_key / BBM_OPENAI_API_KEY	o1
  o1mini	--openai_key / BBM_OPENAI_API_KEY	o1-mini
  o3mini	--openai_key / BBM_OPENAI_API_KEY	o3-mini
  openai	--openai_key / BBM_OPENAI_API_KEY	Requires --model_list. Use any OpenAI-compatible model
  claude-*	--claude_key / BBM_CLAUDE_API_KEY	Prefix match. e.g. --model claude-sonnet-4-20250514
  gemini	--gemini_key / BBM_GOOGLE_GEMINI_KEY	Gemini Flash. Supports --model_list
  geminipro	--gemini_key / BBM_GOOGLE_GEMINI_KEY	Gemini Pro
  groq	--groq_key / BBM_GROQ_API_KEY	Requires --model_list
  xai	--xai_key / BBM_XAI_API_KEY	Grok
  qwen-mt-turbo	--qwen_key / BBM_QWEN_API_KEY	Qwen fast translation model
  qwen-mt-plus	--qwen_key / BBM_QWEN_API_KEY	Qwen high-quality translation model
  google	N/A	Free. No API key needed
  caiyun	--caiyun_key / BBM_CAIYUN_API_KEY	Caiyun
  deepl	--deepl_key / BBM_DEEPL_API_KEY	DeepL (paid)
  deeplfree	N/A	DeepL Free
  tencentransmart	N/A	Tencent TranSmart. Free
  customapi	--custom_api / BBM_CUSTOM_API	Custom translation API

  For any OpenAI-compatible API not listed above, use --provider instead (see Custom API Provider section).

• --test:

  Use --test option to preview the result if you haven't paid for the service. Note that there is a limit and it may take some time.

• --language:

  Set the target language like --language "Simplified Chinese". Default target language is "Simplified Chinese". Read available languages by helper message: python make_book.py --help

• --proxy:

  Use --proxy option to specify proxy server for internet access. Enter a string such as http://127.0.0.1:7890.

• --resume:

  Use --resume option to manually resume the process after an interruption.

  python3 make_book.py --book_name test_books/animal_farm.epub --model google --resume
  

• --translate-tags:

  epub is made of html files. By default, we only translate contents in <p>. Use --translate-tags to specify tags need for translation. Use comma to separate multiple tags. For example: --translate-tags h1,h2,h3,p,div

• --exclude-translate-tags:

  Use --exclude-translate-tags to exclude content within specified HTML tags from translation. This is useful for preserving code blocks, preformatted text, or other special content. Use comma to separate multiple tags. Default: sup,code. For example: --exclude-translate-tags code,pre

  Tip: Use --exclude-translate-tags "" to translate all content including code blocks (overrides the default exclusion).

• --book_from:

  Use --book_from option to specify e-reader type (Now only kobo is available), and use --device_path to specify the mounting point.

• --api_base:

  If you want to change api_base like using Cloudflare Workers, use --api_base <URL> to support it. Note: the api url should be 'https://xxxx/v1'. Quotation marks are required.

• --allow_navigable_strings:

  If you want to translate strings in an e-book that aren't labeled with any tags, you can use the --allow_navigable_strings parameter. This will add the strings to the translation queue. Note that it's best to look for e-books that are more standardized if possible.

• --prompt:

  To tweak the prompt, use the --prompt parameter. Valid placeholders for the user role template include {text} and {language}. It supports a few ways to configure the prompt:

  • If you don't need to set the system role content, you can simply set it up like this: --prompt "Translate {text} to {language}." or --prompt prompt_template_sample.txt (example of a text file can be found at ./prompt_template_sample.txt).

  • If you need to set the system role content, you can use the following format: --prompt '{"user":"Translate {text} to {language}", "system": "You are a professional translator."}' or --prompt prompt_template_sample.json (example of a JSON file can be found at ./prompt_template_sample.json).

  • You can now use PromptDown format (.md files) for more structured prompts: --prompt prompt_md.prompt.md. PromptDown supports both traditional system messages and developer messages (used by newer AI models). Example:

    # Translation Prompt
    
    ## Developer Message
    You are a professional translator who specializes in accurate translations.
    
    ## Conversation
    
    | Role | Content                                                        |
    | ---- | -------------------------------------------------------------- |
    | User | Please translate the following text into {language}:\n\n{text} |
    

  • You can also set the user and system role prompt by setting environment variables: BBM_CHATGPTAPI_USER_MSG_TEMPLATE and BBM_CHATGPTAPI_SYS_MSG.

• --batch_size:

  Use the --batch_size parameter to specify the number of lines for batch translation (default is 10, currently only effective for txt files).

• --accumulated_num:

  Wait for how many tokens have been accumulated before starting the translation. gpt3.5 limits the total_token to 4090. For example, if you use --accumulated_num 1600, maybe openai will output 2200 tokens and maybe 200 tokens for other messages in the system messages user messages, 1600+2200+200=4000, So you are close to reaching the limit. You have to choose your own value, there is no way to know if the limit is reached before sending

• --use_context:

  prompts the model to create a three-paragraph summary. If it's the beginning of the translation, it will summarize the entire passage sent (the size depending on --accumulated_num). For subsequent passages, it will amend the summary to include details from the most recent passage, creating a running one-paragraph context payload of the important details of the entire translated work. This improves consistency of flow and tone throughout the translation. This option is available for all ChatGPT-compatible models and Gemini models.

• --context_paragraph_limit:

  Use --context_paragraph_limit to set a limit on the number of context paragraphs when using the --use_context option.

• --parallel-workers:

  Use --parallel-workers to enable parallel EPUB chapter processing. Values greater than 1 spin up multiple workers (recommended: 2-4) and automatically fall back to sequential mode for single-chapter books.

• --temperature:

  Use --temperature to set the temperature parameter for chatgptapi/gpt4/claude models. For example: --temperature 0.7.

• --block_size:

  Use --block_size to merge multiple paragraphs into one block. This may increase accuracy and speed up the process. For example: --block_size 5.

• --single_translate:

  Use --single_translate to output only the translated book without creating a bilingual version.

• --translation_style:

  example: --translation_style "color: #808080; font-style: italic;"

• --retranslate "$translated_filepath" "file_name_in_epub" "start_str" "end_str"(optional):

  Retranslate from start_str to end_str's tag:

  python3 "make_book.py" --book_name "test_books/animal_farm.epub" --retranslate 'test_books/animal_farm_bilingual.epub' 'index_split_002.html' 'in spite of the present book shortage which' 'This kind of thing is not a good symptom. Obviously'
  

  Retranslate start_str's tag:

  python3 "make_book.py" --book_name "test_books/animal_farm.epub" --retranslate 'test_books/animal_farm_bilingual.epub' 'index_split_002.html' 'in spite of the present book shortage which'
  

• --extra_body:

  Pass additional JSON parameters to the API. This is useful for models that support extra configuration options. Provide a JSON string with the desired parameters.

  python3 make_book.py --book_name test_books/animal_farm.epub --openai_key ${openai_key} --extra_body '{"chat_template_kwargs": {"enable_thinking": false}}'
  

• --provider:

  Use a custom provider defined in bbm_providers.json. Mutually exclusive with --model. See the "Custom API Provider" section above.

• --api_key:

  API key for custom providers (used with --provider). Can also be set via the env_key field in the provider config.

Examples

Note if use pip install bbook_maker all commands can change to bbook_maker args

# Test quickly
python3 make_book.py --book_name test_books/animal_farm.epub --openai_key ${openai_key}  --test --language zh-hans

# Test quickly for src
python3 make_book.py --book_name test_books/Lex_Fridman_episode_322.srt --openai_key ${openai_key}  --test

# Or translate the whole book
python3 make_book.py --book_name test_books/animal_farm.epub --openai_key ${openai_key} --language zh-hans

# Or translate the whole book using Gemini flash
python3 make_book.py --book_name test_books/animal_farm.epub --gemini_key ${gemini_key} --model gemini

# Translate an EPUB with parallel chapter processing
python3 make_book.py --book_name test_books/animal_farm.epub --openai_key ${openai_key} --parallel-workers 4

# Use a specific list of Gemini model aliases
python3 make_book.py --book_name test_books/animal_farm.epub --gemini_key ${gemini_key} --model gemini --model_list gemini-2.5-flash,gemini-2.0-flash

# Set env OPENAI_API_KEY to ignore option --openai_key
export OPENAI_API_KEY=${your_api_key}

# Use the GPT-4 model with context to Japanese
python3 make_book.py --book_name test_books/animal_farm.epub --model gpt4 --use_context --language ja

# Use a specific OpenAI model alias
python3 make_book.py --book_name test_books/animal_farm.epub --model openai --model_list gpt-4-1106-preview --openai_key ${openai_key}

**Note** you can use other `openai like` model in this way
python3 make_book.py --book_name test_books/animal_farm.epub --model openai --model_list yi-34b-chat-0205 --openai_key ${openai_key} --api_base "https://api.lingyiwanwu.com/v1"

# Use a specific list of OpenAI model aliases
python3 make_book.py --book_name test_books/animal_farm.epub --model openai --model_list gpt-4-1106-preview,gpt-4-0125-preview,gpt-3.5-turbo-0125 --openai_key ${openai_key}

# Use the DeepL model with Japanese
python3 make_book.py --book_name test_books/animal_farm.epub --model deepl --deepl_key ${deepl_key} --language ja

# Use the Claude model with Japanese
python3 make_book.py --book_name test_books/animal_farm.epub --model claude --claude_key ${claude_key} --language ja

# Use the CustomAPI model with Japanese
python3 make_book.py --book_name test_books/animal_farm.epub --model customapi --custom_api ${custom_api} --language ja

# Use a custom provider (e.g. DeepSeek)
python3 make_book.py --book_name test_books/animal_farm.epub --provider deepseek --api_key sk-xxx --language ja

# Translate contents in <div> and <p>
python3 make_book.py --book_name test_books/animal_farm.epub --translate-tags div,p

# Tweaking the prompt
python3 make_book.py --book_name test_books/animal_farm.epub --prompt prompt_template_sample.txt
# or
python3 make_book.py --book_name test_books/animal_farm.epub --prompt prompt_template_sample.json
# or
python3 make_book.py --book_name test_books/animal_farm.epub --prompt "Please translate \`{text}\` to {language}"

# Translate books download from Rakuten Kobo on kobo e-reader
python3 make_book.py --book_from kobo --device_path /tmp/kobo

# translate txt file
python3 make_book.py --book_name test_books/the_little_prince.txt --test --language zh-hans
# aggregated translation txt file
python3 make_book.py --book_name test_books/the_little_prince.txt --test --batch_size 20

# Using Caiyun model to translate
# (the api currently only support: simplified chinese <-> english, simplified chinese <-> japanese)
# the official Caiyun has provided a test token (3975l6lr5pcbvidl6jl2)
# you can apply your own token by following this tutorial(https://bobtranslate.com/service/translate/caiyun.html)
python3 make_book.py --model caiyun --caiyun_key 3975l6lr5pcbvidl6jl2 --book_name test_books/animal_farm.epub


# Set env BBM_CAIYUN_API_KEY to ignore option --openai_key
export BBM_CAIYUN_API_KEY=${your_api_key}

More understandable example

python3 make_book.py --book_name 'animal_farm.epub' --openai_key sk-XXXXX --api_base 'https://xxxxx/v1'

# Or python3 is not in your PATH
python make_book.py --book_name 'animal_farm.epub' --openai_key sk-XXXXX --api_base 'https://xxxxx/v1'

Microsoft Azure Endpoints

python3 make_book.py --book_name 'animal_farm.epub' --openai_key XXXXX --api_base 'https://example-endpoint.openai.azure.com' --deployment_id 'deployment-name'

# Or python3 is not in your PATH
python make_book.py --book_name 'animal_farm.epub' --openai_key XXXXX --api_base 'https://example-endpoint.openai.azure.com' --deployment_id 'deployment-name'

Docker

You can use Docker if you don't want to deal with setting up the environment.

# Build image
docker build --tag bilingual_book_maker .

# Run container
# "$folder_path" represents the folder where your book file locates. Also, it is where the processed file will be stored.

# Windows PowerShell
$folder_path=your_folder_path # $folder_path="C:\Users\user\mybook\"
$book_name=your_book_name # $book_name="animal_farm.epub"
$openai_key=your_api_key # $openai_key="sk-xxx"
$language=your_language # see utils.py

docker run --rm --name bilingual_book_maker --mount type=bind,source=$folder_path,target='/app/test_books' bilingual_book_maker --book_name "/app/test_books/$book_name" --openai_key $openai_key --language $language

# Linux
export folder_path=${your_folder_path}
export book_name=${your_book_name}
export openai_key=${your_api_key}
export language=${your_language}

docker run --rm --name bilingual_book_maker --mount type=bind,source=${folder_path},target='/app/test_books' bilingual_book_maker --book_name "/app/test_books/${book_name}" --openai_key ${openai_key} --language "${language}"

For example:

# Linux
docker run --rm --name bilingual_book_maker --mount type=bind,source=/home/user/my_books,target='/app/test_books' bilingual_book_maker --book_name /app/test_books/animal_farm.epub --openai_key sk-XXX --test --test_num 1 --language zh-hant

Notes

1. API token from free trial has limit. If you want to speed up the process, consider paying for the service or use multiple OpenAI tokens
2. PR is welcome

Thanks

• @yetone

Contribution

• Any issues or PRs are welcome.
• TODOs in the issue can also be selected.
• Please run black make_book.py² before submitting the code.

Others better

• 书译 BookTranslator -> Book Translator

Appreciation

Thank you, that's enough.

Footnotes

1. https://platform.openai.com/account/api-keys ↩

2. https://github.com/psf/black ↩