The OggSQUISH Beta Release Page
Last Updated: August 14, 1996
The beta releases have begun!
Our first full beta release of lossless OggSquish appears below. This
CODEC is supported; use it for all your lossless audio
compression needs! All future releases of OggSquish will be
compatable with the bitstreams you create now.
This lossless release for UNIX will soon be followed by releases for
Windows and PowerMacintosh, as well as lossy-capable versions.
What is in this beta?
The source code archives (.tgz) contain the source to an example Ogg
application, as well as full source to libogg 0.98.8.
Application features
The application available for download below (right now only UNIX,
soon to be joined by Win95 and PowerMac) can convert raw, .WAV, .AIFF
and .AIFC files to Ogg format, play these files back directly (under
Linux only, soon to add SGI) as well as convert Ogg files back to raw,
.WAV and .AIFC formats. The application can efficiently handle
samples from 4 bit mono to 24 bit quadraphonic.
This application (ogg) currently supports uncompressed, losslessly compressed
and quasi-losslessly compressed Ogg samples. Lossy and perceptual
lossy compressions will apear in a later release (in September).
Libogg features
Libogg 0.98.7 is tested and fully compatable (as is!) with Linux,
NetBSD, Solaris, HPUX, AIX, IRIX, Ultrix, Win32, Macintosh and
PowerMacs. It provides complete OggSquish compatability on each
platform in ready-to-embed form.
Performance
- Compression/decompression speed:
Realtime decode/playback of stereo CD quality audio on
Pentiums,
mono CD quality on 486s. Everything else (with the exception
of the 68k Mac) is even faster; SGI Indys, for example, can do stereo
CD easily.
- Lossless compression ratios:
- 8 bit speech: from 2.5:1 to 4:1
- 16 bit speech: about 2-3:1 (depending on background noise)
- 8 bit music and general purpose: 2.5-3:1
- 16 bit music: 1.5-2:1
Why are lossless compression ratios so... wimpy? From the Ogg man page:
Noisy input sound will not compress well when compressing
losslessly; noise is randomness in the sound signal that
is, by its nature, losslessly incompressible. This means
that a 16 bit sound file with 8 bits of noise can be com-
pressed at most 2:1 (realistically, much less). Input
from the highest quality cassette tape or PC sound card
will typically have 6-8 bits of noise or more. Input from
a CD will still likely have 3 or 4 (even if it's read
directly as data) from the original recording process!
Even further complicating this is when the sound is sup-
posed to be noisy, like a cymbal crash. A loud cymbal
crash will contain perhaps 14 or 15 bits of pure noise
which means that the signal is barely compressible at all.
For this reason, lossless compression is very poorly
suited to noisy samples. Lossy compression does much bet-
ter; it is allowed to lose information so long as it pro-
duces an output that sounds the same.
Note that OggSquish closely approaches the theoretical minimum file
size for a file with a given amount of non-periodic 'noise'.
Announcements
If you wish to be added to the OggSQUISH announcement mailing list, send me mail.
Documentation
Drafts of the libogg 0.98 application interface
specification and API description are now
available on the OggSquish documentation page.
Downloads
Current source version: 0.98 rev 8
READ THESE DISTRIBUTION TERMS BEFORE DOWNLOADING
Full Ogg/Libogg source (0.98 rev 8)
Ogg UNIX man page
Note: These precompiled binaries are for 0.98.7; they will be replaced
with rev 8 (to match the source) soon.
Linux ELF binary (gzipped)
Linux a.out binary (gzipped)
Sun4m Solaris binary (gzipped)
SGI IRIX binary (gzipped)
New features in 0.98.8
- Improved stereo analysis (faster, mainly).
- Faster I/O code
- Workaround to a hardware bug affecting 16 bit playback in the ESS AudioDrives
- Direct playback on Silicon Graphics machines
OggSQUISH, OggScript, OggLite, the Thor-and-the-Snake logo and
Xiphophorus are trademarks (tm) of the Xiphophorus company. The
OggSQUISH library and OggSQUISH applications by Xiphophorus are
copyright (C) 1994-1996 Xiphophorus. All rights reserved.
DeskFish WWW Server /
Address comments to: xiphmont@cs.titech.ac.jp