designates a pure
data compression format not
providing file archival feature, its BZip2 compression algorithm
is based on Burrows–Wheeler
Compressed files are usually identified by .bz2 extension, and can
contain a single input file.
TBZ / TAR.BZ file extension
Due this by-design limitation, on Unix/Linux systems BZip2 compression
(as well as Gzip, XZ,...) is usually cascaded to TAR archive creation
- multiple files
and metadata (file attributes, date/time etc) are consolidated into a
single uncompressed .tar container - producing TBZ2 file, which can be
identified with TBZ, TB2, or TAR.BZ2 extension.
PeaZip features creation and
extraction of BZ2 files, can read (open, test and
extract) and write (compress to) BZ2 file type. Also, PeaZip can be set
use BZip2 compression as alternative algorithm for ZIP and 7Z formats,
in Advanced options tab.
BZ2 file format specs
Compression speed is
somewhat slower than in zip format
format, which employs classic Deflate algorithm (even if correctly
algorithm can be easily made
parallel, and benefit of recent multi-core CPU), but faster than more
powerful compression schemes as in RAR
format, 7Z format, and new ZIPX format (which can optionally use
BZip2 algorithm as compressor).
ratio, also, is usually intermediate between older Deflate-based ZIP/GZ
files and modern RAR, 7Z, ZIPX formats.
Use of BZ2 and related file
When is BZ2
BZip2 compression is usually applied to TAR
archive format, which is usually
employed to provide archiving of data and metadata on Unix and
Unix-like systems as BSD, Linux and macOS,
and it can also be used as alternative compression
algorithm in ZIP and 7Z files - resulting archives can be read from
most file archivers (including PeaZip).
It can be recommended when it is desired a better compression than
classic Deflate-based ZIP / GZIP compression, and in all cases it is
preferable an algorithm faster and less heavy on memory and CPU than
LZMA-based 7Z or PPMd-based RAR compression.
Read more about
.bz2 file type on BZip
official domain, and Burrows–Wheeler
transform entry on
Julian Seward, 1996
limited to 1 single file as input
BZ2 format features good speed. Designed with parallelism in mind bzip2
compression can be, theoretically,
implemented as separate threads for each input part.
BZ2 format features good compression ratio, improved over Deflate but
lacking behind modern compression
algorithms employed in RAR and 7Z formats, recommended for backup large
quantity of data as intermediate alternative between fast zip/gzip and
powerful rar/7z compression.
BZ2 format is meant only for providing single-file compression, lacks
archiving and encryption features by design.
Synopsis: What is BZ2
file format extension. Bzip2 compression algorithm. What are .BZ2
compressed file type features and specifications. TAR.BZ2 and TBZ
Topics: BZ2 file
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