B1 (archive format) explained

B1
Extension:	.b1
Mime:	application/x-b1
Owner:	Catalina Group Ltd
Released:	2011
Genre:	Data compression

B1 is an open archive file format that supports data compression and archiving. B1 files use the file extension ".b1" or ".B1" and the MIME media type application/x-b1. B1 incorporates the LZMA compression algorithm.^[1] B1 archive combines a number of files and folders into one or more volumes, optionally adding compression and encryption. Construction of the B1 archive involves creating a binary stream of records and building volumes of that stream. The B1 archive format supports password-based AES-256 encryption.^[2] B1 files are created and opened with its native open-source B1 Pack Tool, as well as B1 Free Archiver utility.^{[3] [4]}

B1 Pack Project

B1 Pack is an open-source software project that produces a cross-platform command-line tool and a Java library for creating and extracting file archives in the B1 archive format. Source code of the project is published at GitHub.^[5] B1 Pack Project is released under the Apache License.^[6] The B1 Pack Tool module builds a single executable JAR file which can create, list, and extract B1 archive files from a command-line interface.^[7]

B1 format features

• Support for Unicode names for files inside an archive.
• Archives and the files inside it can be of any size.
• Support for split archives, that consist of several parts.
• Integrity check with the Adler-32 algorithm.
• Data compression using the LZMA algorithm.
• Supports encryption with the AES algorithm.^[8]

API features

• Instant creation of an archive without reading from/writing to a file system.
• Producing only a byte range of an archive, e.g. for resuming downloads.
• Streaming archive content without prior knowledge of all the files being packaged.

External links

• B1 Pack Project

Notes and References

1. http://whatis.techtarget.com/fileformat/B1-Open-source-backup-and-archive-file-format "B1 File Format"
2. http://www.file-extensions.org/b1-file-extension "B1 file extension - B1 compressed archive"
3. http://www.fileinfo.com/extension/b1 "B1 File Extension"
4. http://www.digitalquest.org/2013/02/extract-compressed-files-without-any.html "Extract compressed files without any software"
5. https://github.com/b1-pack/b1-pack "B1-Pack"
6. http://dev.b1.org/standard/license.html "The Apache Software License, v2.0"
7. http://dev.b1.org/cli/index.html "B1 Pack CLI"
8. http://dev.b1.org/standard/archive-format.html "B1 Pack Project"