.\" -*- mode: troff; coding: utf-8 -*-
.\" Automatically generated by Podwrapper::Man 1.47.8 (Pod::Simple 3.47)
.\"
.\" Standard preamble:
.\" ========================================================================
.de Sp \" Vertical space (when we can't use .PP)
.if t .sp .5v
.if n .sp
..
.de Vb \" Begin verbatim text
.ft CW
.nf
.ne \\$1
..
.de Ve \" End verbatim text
.ft R
.fi
..
.\" \*(C` and \*(C' are quotes in nroff, nothing in troff, for use with C<>.
.ie n \{\
.    ds C` ""
.    ds C' ""
'br\}
.el\{\
.    ds C`
.    ds C'
'br\}
.\"
.\" Escape single quotes in literal strings from groff's Unicode transform.
.ie \n(.g .ds Aq \(aq
.el       .ds Aq '
.\"
.\" If the F register is >0, we'll generate index entries on stderr for
.\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index
.\" entries marked with X<> in POD.  Of course, you'll have to process the
.\" output yourself in some meaningful fashion.
.\"
.\" Avoid warning from groff about undefined register 'F'.
.de IX
..
.nr rF 0
.if \n(.g .if rF .nr rF 1
.if (\n(rF:(\n(.g==0)) \{\
.    if \nF \{\
.        de IX
.        tm Index:\\$1\t\\n%\t"\\$2"
..
.        if !\nF==2 \{\
.            nr % 0
.            nr F 2
.        \}
.    \}
.\}
.rr rF
.\"
.\" Required to disable full justification in groff 1.23.0.
.if n .ds AD l
.\" ========================================================================
.\"
.IX Title "nbdkit-indexed-gzip-filter 1"
.TH nbdkit-indexed-gzip-filter 1 2026-04-25 nbdkit-1.47.8 NBDKIT
.\" For nroff, turn off justification.  Always turn off hyphenation; it makes
.\" way too many mistakes in technical documents.
.if n .ad l
.nh
.SH NAME
nbdkit\-indexed\-gzip\-filter \- access .gz contents efficiently
.SH SYNOPSIS
.IX Header "SYNOPSIS"
.Vb 2
\& nbdkit \-\-filter=indexed\-gzip PLUGIN gzip\-index\-path=PATH
\&                                     [gzip\-index\-span=SIZE]
.Ve
.SH DESCRIPTION
.IX Header "DESCRIPTION"
\&\f(CW\*(C`nbdkit\-indexed\-gzip\-filter\*(C'\fR is a filter for nbdkit that provides
fast and efficient random\-access to gzip\-compressed data.
.PP
The standard \fBnbdkit\-gzip\-filter\fR\|(1) decompresses the entire archive
to a temporary file, which means you need to have enough storage or
memory to store the complete uncompressed input.
.PP
With this filter, the entire archive still needs to be decompressed
once, but only an index file needs to be stored in storage or memory,
which (depending on user\-specified distance between index points) may
be 0.3% to 3% of the size of the uncompressed archive.
.SH PARAMETERS
.IX Header "PARAMETERS"
.IP \fBgzip\-index\-path=\fRPATH 4
.IX Item "gzip-index-path=PATH"
Path to the complete gzip index file (created if it doesn\*(Aqt exist,
reused if it does).
.Sp
This parameter is required.
.IP \fBgzip\-index\-span=\fRSIZE 4
.IX Item "gzip-index-span=SIZE"
Number of bytes between index points. Eg. 1M, 10M etc. (default: 1MB)
.Sp
A span of 10M produces an index file of eg, ~0.3% of uncompressed input
.Sp
A span of 1M produces an index file of eg, ~3% of uncompressed input.
.Sp
Smaller span improves random\-access performance, since on average it
means fewer bytes to decompress until reaching the requested byte
(with the trade\-off of a larger index file).
.SH FILES
.IX Header "FILES"
.ie n .IP \fR\fI$filterdir\fR\fI/nbdkit\-indexed\-gzip\-filter.so\fR 4
.el .IP \fR\f(CI$filterdir\fR\fI/nbdkit\-indexed\-gzip\-filter.so\fR 4
.IX Item "$filterdir/nbdkit-indexed-gzip-filter.so"
The filter.
.Sp
Use \f(CW\*(C`nbdkit \-\-dump\-config\*(C'\fR to find the location of \f(CW$filterdir\fR.
.SH VERSION
.IX Header "VERSION"
nbdkit\-indexed\-gzip\-filter first appeared in nbdkit 1.46.
.SH "SEE ALSO"
.IX Header "SEE ALSO"
\&\fBnbdkit\fR\|(1), \fBnbdkit\-filter\fR\|(3), \fBnbdkit\-gzip\-filter\fR\|(1)
.SH AUTHORS
.IX Header "AUTHORS"
Shasheen Ediriweera
.PP
Mark Adler
.SH COPYRIGHT
.IX Header "COPYRIGHT"
Copyright (C) 2025 Shasheen Ediriweera
.PP
Copyright (C) 2005, 2012, 2018, 2023, 2024 Mark Adler
.SH LICENSE
.IX Header "LICENSE"
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:
.IP \(bu 4
Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
.IP \(bu 4
Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
.IP \(bu 4
Neither the name of Red Hat nor the names of its contributors may be
used to endorse or promote products derived from this software without
specific prior written permission.
.PP
THIS SOFTWARE IS PROVIDED BY RED HAT AND CONTRIBUTORS \*(Aq\*(AqAS IS\*(Aq\*(Aq AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT OR
CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.
