(registered 2026-10-27, last updated 2026-10-27)

Media type name: application

Media subtype name: vnd.ngdtuanh.abookproj+zip

Required parameters: N/A

Optional parameters: N/A

Encoding considerations: binary

Security considerations: The file is a ZIP archive of audio, images, plain text and an SQLite database. It contains no executable or active content and no external references. Readers must reject entry names outside the rules of the specification (no absolute paths, no '..'), enforce limits on entry count and sizes against decompression bombs, check free space, and verify every entry's size and SHA-256 against project.json. The database is read only by the application with fixed queries. The file may contain the full text of the book being produced and the folder paths of the computer that packed it; it carries no listening data.

Interoperability considerations: The first ZIP entry is 'mimetype', stored uncompressed, containing the media type string, so the format can be identified from the first bytes (as in EPUB). The related finished-audiobook format is application/vnd.ngdtuanh.abook+zip.

Published specification: https://github.com/ntanhpro1221/ABook/blob/main/_internal/docs/ABOOKPROJ_FILE_FORMAT.md

Applications which use this media: ABook, an audiobook production and listening app for Windows and Android (https://github.com/ntanhpro1221/ABook): the Studio packs and opens projects.

Fragment identifier considerations: N/A

Restrictions on usage: None

Additional information:

1. Deprecated alias names for this type: N/A
2. Magic number(s): PK\x03\x04 at offset 0; the ASCII string 'mimetypeapplication/vnd.ngdtuanh.abookproj+zip' at offset 30
3. File extension(s): .abookproj
4. Macintosh file type code: N/A
5. Object Identifiers: N/A

Person to contact for further information:

1. Name: Nguyễn Duy Tuấn Anh
2. Email: ntanhpro1221&gmail.com

Intended usage: COMMON

Author/Change controller: Nguyễn Duy Tuấn Anh <ntanhpro1221&gmail.com>