Documentation files for Oggz
----------------------------
PATCHES: Instructions for generating patches
README: this file
README.symbian: Instructions for building for Symbian
README.win32: Instructions for building on Win32
Run:
----
$ oggz help
for documentation of the various oggz commands.
About Oggz
==========
Oggz comprises liboggz and the tool oggz, which provides commands to
inspect, edit and validate Ogg files. The oggz-chop tool can also be
used to serve time ranges of Ogg media over HTTP by any web server that
supports CGI.
liboggz is a C library for reading and writing Ogg files and streams.
It offers various improvements over the reference libogg, including
support for seeking, validation and timestamp interpretation. Ogg is
an interleaving data container developed by Monty at Xiph.Org,
originally to support the Ogg Vorbis audio format but now used for
many free codecs including Dirac, FLAC, Speex and Theora.
Dependencies
------------
Oggz depends only on libogg, available in most free software
distributions, or in source form at: http://xiph.org/downloads/
Support is built-in for parsing the headers of and seeking to time
positions in Ogg Dirac, FLAC, Speex, Theora and Vorbis. Oggz is also
compatible with Annodex streams, and supports seeking on all tracks
described in an Ogg Skeleton track.
Installation
------------
Release archives can be installed using the conventional commands:
$ ./configure
$ make check
$ sudo make install
sequence. Configuration details are in the file INSTALL. If you obtained
this source by svn, first run "./autogen.sh" to create the configure script,
then run the above commands.
Read the file README.win32 for installing under MS Windows, and
README.symbian for information about building for Symbian devices.
Source layout
-------------
doc/
doc/liboggz autocreated by the doxygen tool from comments
contained in the public C header files
include/ public C header files
src/
src/liboggz/ library source code.
src/tools/ command line tools
src/examples/ example programs using liboggz
src/tests/ unit and functional tests
symbian/ files necessary to compile the library for Symbian
win32/ files necessary to compile the library and tools for
Microsoft Windows
Developers
----------
liboggz is maintained in git at git://git.xiph.org/liboggz.git
A list of outstanding tasks is maintained in the TODO file of this source
distribution. When implementing anything listed in this file, please update
it by deleting that entry, and include that as part of the patch or commit
that implements the fix.
Please send patches to ogg-dev@xiph.org
Programming with liboggz
------------------------
liboggz supports the flexibility afforded by the Ogg file format while
presenting the following API niceties:
* Full API documentation
* Comprehensive test suite of read, write and seeking behavior.
The entire test suite can be run under valgrind if available.
* Developed and tested on GNU/Linux, Darwin/MacOSX, Win32 and
Symbian OS. May work on other Unix-like systems via GNU autoconf.
For Win32: nmake Makefiles, Visual Studio .NET 2003, 2005 and 2008
solution files are provided in the source distribution.
* Strict adherence to the formatting requirements of Ogg bitstreams,
to ensure that only valid bitstreams are generated; writes can fail
if you try to write illegally structured packets.
* A simple, callback based open/read/close or open/write/close
interface to raw Ogg files.
* Writing automatically interleaves with packet queuing, and provides
callback based notification when this queue is empty
* A customisable seeking abstraction for seeking on multitrack Ogg
data. Seeking works easily and reliably on multitrack and multi-codec
streams, and can transparently parse Theora, Speex, Vorbis, FLAC,
PCM, CMML and Ogg Skeleton headers without requiring linking to those
libraries. This allows efficient use on servers and other devices
that need to parse and seek within Ogg files, but do not need to do
a full media decode.
Full documentation of the liboggz API, customization and installation,
and mux and demux examples can be read online at:
http://www.xiph.org/oggz/doc/
oggz tool
---------
Usage: oggz <subcommand> [options] filename ...
oggz is a commandline tool for manipulating Ogg files. It supports
multiplexed files conformant with RFC3533. Oggz can parse headers for CELT,
CMML, Dirac, FLAC, Kate, PCM, Speex, Theora and Vorbis, and can read and write
Ogg Skeleton logical bitstreams.
Commands:
help Display help for a specific subcommand (eg. "oggz help chop")
Reporting:
codecs Display the codecs present in an Ogg file
diff Hexdump the packets of two Ogg files and output differences.
dump Hexdump packets of an Ogg file, or revert an Ogg file from
such a hexdump.
info Display information about one or more Ogg files and their
bitstreams.
scan Scan an Ogg file and output characteristic landmarks.
validate Validate the Ogg framing of one or more files.
Extraction:
rip Extract one or more logical bitstreams from an Ogg file.
Editing:
chop Extract the part of an Ogg file between given start and/or
end times.
comment List or edit comments in an Ogg file.
merge Merge Ogg files together, interleaving pages in order of
presentation time.
sort Sort the pages of an Ogg file in order of presentation time.
Miscellaneous:
known-codecs List codecs known by this version of oggz
The script bash-completion/oggz enables completion of tool options and codec
names when using the bash shell. Source it from your .profile, or install it
in /etc/bash_completion.d to enable it system-wide.
oggz-chop: General usage and CGI installation
---------------------------------------------
oggz-chop extracts the part of an Ogg file between given start and/or end
times. The output file contains copies of the headers of the input file, and
all the codec data required to correctly decode the content between the start
and end times specified on the commandline. For codecs with data dependencies
like video keyframes, the keyframe prior to the starting time will be included
in the output.
An Apache server can be configured to use oggz-chop to handle all Ogg files
(or, all Ogg files in a particular directory). An example Apache configuration
is in the liboggz source tree, along with a script for installing it on a
Debian server.
The oggz-chop binary checks if it is being run as a CGI script (by checking
some environment variables), and if so acts based on the CGI query parameter
t=, much like mod_annodex. It accepts all the time specifications that
mod_annodex accepts (npt and various smpte framerates), and start and end
times separated by a /.
License
-------
Oggz is Free Software, available under a BSD style license.
More information is available online at the Oggz homepage:
http://xiph.org/oggz/
enjoy :)
--
Conrad Parker
http://www.annodex.net/