Internet Info 1997 December/Internet_Info_CD-ROM_Walnut_Creek_December_1997.iso/faqs/comp/answers/jpeg-faq/part2

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From: [e-mail] (Tom Lane)
Subject: JPEG image compression FAQ, part 2/2
Message-ID: <[e-mail]>
Followup-To: comp.graphics.misc
Summary: System-specific hints and program recommendations for JPEG images
Keywords: JPEG, image compression, FAQ, JPG, JFIF
Supersedes: <[e-mail]>
Reply-To: [e-mail]
Organization: Independent JPEG Group
References: <[e-mail]>
Date: Sun, 26 Oct 1997 15:46:09 GMT
Approved: [e-mail]
Expires: Sun, 23 Nov 1997 15:46:04 GMT
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Sender: [e-mail]
Xref: senator-bedfellow.mit.edu comp.graphics.misc:28570 comp.infosystems.www.authoring.images:29192 comp.answers:28677 news.answers:115370

Archive-name: jpeg-faq/part2
Posting-Frequency: every 14 days
Last-modified: 25 October 1997

This article answers Frequently Asked Questions about JPEG image compression.
This is part 2, covering system-specific hints and program recommendations
for a variety of computer systems.  Part 1 covers general questions and
answers about JPEG.  As always, suggestions for improvement of this FAQ are
welcome.

New since version of 12 October 1997:
  * Corrected info about current SEA version (it's 1.3, not 3.0).


This article includes the following sections:

General info:

[1] What is covered in this FAQ?
[2] How do I retrieve these programs?

Programs and hints for specific systems:

[3] X Windows
[4] Unix (without X)
[5] MS-DOS
[6] Microsoft Windows
[7] OS/2
[8] Macintosh
[9] Amiga
[10] Atari ST
[11] Acorn Archimedes
[12] NeXT
[13] Tcl/Tk
[14] Other systems

Source code for JPEG:

[15] Freely available source code for JPEG

Miscellaneous:

[16] Which programs support progressive JPEG?
[17] Where are FAQ lists archived?


This article and its companion are posted every 2 weeks.  If you can't find
part 1, you can get it from the news.answers archive at rtfm.mit.edu
(see "[17] Where are FAQ lists archived?"). This article changes frequently;
get a new copy if the one you are reading is more than a couple months old.

------------------------------

Subject: [1] What is covered in this FAQ?

This list describes programs that are of particular interest to JPEG users.
For the most part, I concentrate on viewers, since a viewer program is the
first thing you'll need.  Some general image-editing programs are listed
too, especially if they are useful as plain viewers (meaning that they can
load and display an image as quickly and easily as a dedicated viewer).
Programs that convert JPEG to and from other image file formats are also
covered.

I list only freeware and shareware programs that are available on the
Internet by FTP.  Commercial products are intentionally excluded, to keep
the list to a reasonable size and to avoid any appearance of advertising.
Also, I try to list only programs that are popular among Usenet users, as
indicated by comments and recommendations in news articles.  I have no
access to many of the types of systems covered here, so I have to rely on
what other people say about a program to decide whether to list it.  If you
have an opinion pro or con on any program, I'd appreciate hearing it.

This FAQ also includes a few hints that are specific to a machine or
program, and thus don't belong in the general discussion of part 1.

------------------------------

Subject: [2] How do I retrieve these programs?

All the files mentioned in this FAQ are available by standard Internet FTP.
If you don't know how to use FTP, please read the article "Anonymous FTP
FAQ List", which you can get by sending e-mail to [e-mail]
with the single line "send faqs/ftp-list/faq" in the body.
(See also "[17] Where are FAQ lists archived?")  This section gives some
quick reminders which are not meant as a substitute for reading the FTP FAQ.

If you do not have direct access to FTP, you can use an "ftpmail" server to
obtain files by e-mail.  See the FTP FAQ for details.

If you use a WWW browser such as Mosaic or Lynx, it will do FTP for you.
To retrieve a file described here as "site.name:/path/to/file", tell the
browser to open the URL "ftp://site.name/path/to/file".  (If you are reading
this FAQ in the WWW FAQ archive, the file names should appear as links that
you can just click on.)  Don't forget to set save-to-disk mode first.

Many of the pointers given here refer to popular central archive sites,
such as ftp.simtel.net for DOS software or sumex-aim.stanford.edu for Mac.
These sites are often overloaded, and are likely to refuse your connection
request when they are busy.  You can try again at a less popular time of
day, or you can look for a "mirror site".  Most central archive sites have
groups of mirror sites that keep copies of their files.  Find out the name
of the mirror site closest to you, and visit that site instead; it's good
net citizenship and you'll get faster response.  Check the FAQs for the
newsgroups specific to your system type to find lists of mirror sites.
(The archive site may list some mirror sites in its connection-refused error
message.  Unfortunately, some FTP programs won't show you the whole message.
WWW browsers are often bad about this.)

If you are able to reach the archive site, but the file you want doesn't
exist, most likely it's been replaced by a newer version.  Get a directory
listing of the directory that's supposed to contain the file, and look for
a file with a similar name but a higher version number.  (If you find an
out-of-date reference in a *current* version of the JPEG FAQ, I'd
appreciate hearing about it by e-mail.)

Practically all of the files listed here are compressed archive files.
This means you need to retrieve them in binary mode.  (WWW browsers do this
automatically, but many older FTP programs must be told to use binary mode.)
Once you've got the archive file, you'll need a decompressor/dearchiver
to extract the program and documentation files inside it.  Check the FAQs
for your system type to find out where to get dearchiver programs.

------------------------------

Subject: [3] X Windows

XV is an excellent viewer for JPEG, GIF, and many other image formats.
It can also do format conversion and some simple image manipulations.
Get it from ftp.cis.upenn.edu:/pub/xv/xv-3.10a.tar.gz.  Shareware, $25.
Version 3.10 has some nifty new features, and it loads JPEGs noticeably
faster than any prior version.  If you're still using version 2.anything,
it's definitely time to upgrade.  HINT: if you have an 8-bit display then
you need to "lock 8-bit mode" to get decent display of JPEG images.  (But
do NOT do this if you intend to resave the image, because it'll be written
from the 8-bit version, thus costing you image quality.)  You can set this
mode to be default by adding "xv.force8: true" to your .Xdefaults file.

Another excellent choice is John Cristy's free ImageMagick package,
ftp.x.org:/contrib/applications/ImageMagick/ImageMagick-3.7.1.tar.gz.  This
package handles many image processing and conversion tasks.  The ImageMagick
viewer handles 24-bit displays correctly; for colormapped displays, it does
better (though slower) color quantization than XV or the basic IJG JPEG
software.

Both of the above are large, complex packages.  If you just want a simple
image viewer, try xloadimage or xli.  xloadimage views and converts many
image file types including JPEG.  Version 4.1 has better JPEG support than
prior versions and is easier to install.  xloadimage is free and available
from ftp.x.org:/R5contrib/xloadimage.4.1.tar.gz.  xli is a variant version
of xloadimage; xli is slightly better as an interactive viewer, but it can't
be used as a converter, and it supports fewer file formats.  xli is also
free and available from ftp.x.org:/contrib/applications/xli.1.16.tar.gz.

------------------------------

Subject: [4] Unix (without X)

If you want a command-line JPEG conversion program, see the IJG source code
described in section 15.  (This code is included as a subdirectory in most
of the X programs described above, although they may not have the latest
version.)

Non-X viewers are hard to come by, since they are very hardware dependent.
Linux users with VGA/SVGA displays may like zgv.  Version 2.8 is available
from sunsite.unc.edu:/pub/Linux/apps/graphics/viewers/svga/zgv2.8-bin.tar.gz.
(Several other alternatives are available in the same directory.)
If you use a less popular platform, you're probably out of luck.

------------------------------

Subject: [5] MS-DOS

This covers plain DOS; for Windows or OS/2 programs, see the next sections.

NOTE ABOUT SIMTEL FILES: The largest Internet collection of PC-related
programs is the Simtel archives (named for the original archive site, now
defunct).  The principal archive site for these files is ftp.simtel.net,
which is the site referenced by the FTP pointers given below.  However,
there are numerous mirror sites that keep copies of the Simtel files.
For quickest response you should use the mirror site closest to you.
Consult the periodic postings in comp.archives.msdos.announce to find your
nearest mirror site.  If you have no FTP capability, the same postings will
tell you how to retrieve Simtel files by e-mail.  You can also access the
Simtel archives via WWW at www.simtel.net.

QPV (formerly called QPEG) is an extremely fast JPEG viewer. In exchange for
speed, QPV gives up some image quality, particularly on 256-or-less-color
displays.  Its best feature is a really-fast small preview window, which is
great for searching through lots of image files. Also views GIF,TGA,BMP,PNG.
Requires 386-or-better CPU and VGA-or-better display card.  Current version
is 1.7c, available from ftp.tu-clausthal.de:/pub/msdos/graphics/qpv17c.zip.
In the USA, a closer site is ftp.best.com:/pub/bryanw/qpv/.  Shareware, $20.

SEA is a new JPEG/PNG/GIF/etc viewer and file-format converter.  It is
very very fast --- faster than QPV in most cases, according to the authors.
Also, it can read progressive JPEGs; QPV can't.  Current version is 1.3,
available from ftp.simtel.net:/pub/simtelnet/msdos/graphics/sea3.zip.
Shareware, $30.  Requires 386-or-better CPU and VESA-compatible display.

DVPEG is a free viewer for JPEG, GIF, Targa, and PPM files.  Current version
is 3.0l, available from sunee.uwaterloo.ca:/pub/jpeg/viewers/dvpeg30l.zip.
(That's lower case l, not digit 1.)  This is a good basic viewer that comes
in both 286 and 386-and-up versions.  The user interface is clunky but
functional.  DVPEG is substantially faster than it used to be; on hi-color
displays it is nearly as fast as QPV.  On 8-bit displays, its two-pass
quantization mode is slow but gives much better image quality than QPV can
provide.

Lesser-used DOS viewers include:
* DISPLAY, alias DISP.  The Swiss army knife of DOS viewers.  Does almost
  everything, but a bit intimidating for newcomers.  User interface is much
  improved over early versions, but still awkward in places.  Requires 386
  or better.  Freeware.  Current version is 1.89, available from
  ftp.simtel.net:/pub/simtelnet/msdos/graphics/disp189a.zip and disp189b.zip.
* GDS.  A well-done viewer and image converter for many image formats.
  Installation is simple, and the on-line documentation is very good.
  JPEG loading is a bit slower than the above viewers, though.  Shareware,
  $40.  Current version is 3.1f.  A slightly restricted demo version is
  available from ftp.photodex.com:/gds31f.exe.
* NVIEW.  Views JPEG and half a dozen other image formats.  Easy to use,
  very easy to install.  Only moderately fast, but it has lots of options.
  Supports hi-color and true-color modes on some cards, but not mine :-(.
  Requires 386 or better.  Current version is 1.50, available from
  ftp.simtel.net:/pub/simtelnet/msdos/graphics/nview150.zip. Shareware, $29.
* CSHOW or CompuShow (recently renamed 2SHOW).  This is a widely used viewer
  for GIF and other formats.  Versions prior to CSHOW 9.00 or 2SHOW 2.00 had
  absolutely abysmal JPEG support; if you have one of those, toss it and get
  a newer version.  The current release is still the slowest DOS JPEG viewer
  listed here, but it's faster than it used to be, and image quality and
  robustness have improved substantially.  The main reason to use CSHOW
  as a JPEG viewer is that it supports a wide range of pre-VGA display
  hardware (most of the above viewers require VGA or better).  Also, CSHOW
  doesn't require a 386.  Current version is 2.04, available from
  ftp.simtel.net:/pub/simtelnet/msdos/graphics/2show204.zip. Shareware, $39.

Due to the remarkable variety of PC graphics hardware, any one of these
viewers might not work on your particular machine.  If you can't get *any*
of them to work, you'll need to use one of the following conversion programs
to convert JPEG to GIF, then view with your favorite GIF viewer.  (If you
have hi-color hardware, don't use GIF as the intermediate format; try to
find a hi-color BMP- or TARGA-capable viewer instead.)

The free IJG JPEG converters are available from
ftp.simtel.net:/pub/simtelnet/msdos/graphics/jpeg6a.zip (or jpeg6a32.zip
if you have a 386-or-better CPU and extended memory).  These programs will
convert JPEG to and from GIF, BMP, Targa, and PPM formats; they are DOS
compilations of the free source code described in section 15.

Handmade Software offers free JPEG<=>GIF conversion tools, GIF2JPG/JPG2GIF.
These are quite slow and are limited to conversion to and from GIF format;
thus they can't produce 24-bit color output from a JPEG.  The sole advantage
of these tools is that they will read and write HSI's proprietary JPEG
format as well as the Usenet-standard JFIF format.  Since HSI-format files
are rather widespread on BBSes, this is a useful capability.  Version 2.0
of these tools is free (prior versions were shareware), and is available
from ftp.simtel.net:/pub/simtelnet/msdos/graphics/gif2jpg2.zip.
NOTE: do not use HSI format for files to be posted on Usenet, since it is
not readable by any non-HSI software.

Handmade Software also has a shareware image conversion and manipulation
package, Image Alchemy.  This will translate JPEG files (both JFIF and HSI
formats) to and from many other image formats.  It can also display images.
A demo version of Image Alchemy version 1.9 is available from
http://www.handmadesw.com/hsi/download.html.

JPGINDEX is a useful tool for making indexes of JPEG image collections.
Available from ftp.simtel.net:/pub/simtelnet/msdos/graphics/jpgidx13.zip.

------------------------------

Subject: [6] Microsoft Windows

ACDSee is a very fast, easy to use JPEG/GIF/PNG/etc viewer.  Good viewing
and browsing capabilities, including a fast preview display; but no image
editing or conversion functions.  The Windows 95/NT version supports
progressive JPEG, but the Windows 3.1 release does not.  Both versions
are available from http://www.acdvictoria.com/acd/download.html or
ftp.acdsystems.com:/pub/acdsee95/.  Shareware, $30.

LView Pro is a viewer/editor/converter for JPEG, GIF, BMP, and other
formats.  It offers a wide array of image editing functions and can load
JPEGs in either fast/low-quality or slow/high-quality modes.  Requires 386
or better CPU.  The current version, 1.D, runs under Windows 95, Windows NT,
or Windows 3.1 with Win32s 32-bit extension.  It's available from
ftp.std.com:/ftp/vendors/mmedia/lview/lviewpro.zip.  Shareware, $30.
An older version that can run under vanilla Windows 3.1 is
ftp.simtel.net:/pub/simtelnet/win3/graphics/lviewp1b.zip.

VuePrint is a widely used viewer and printer for JPEG, GIF, BMP, and
other formats.  Shareware, $40.  Version 5.0 is available from
http://www.hamrick.com/.

ThumbsPlus is an image browser and cataloger that handles many file formats.
It can also do some editing and format conversion, but indexing a large
image collection is what it's really aimed at.  Current version is 3.0c, at
ftp.cerious.com:/pub/cerious/thmpls32.exe.  Shareware, $70.  Requires
Windows 95 or NT, or Windows 3.1 with Win32s.

Another good viewer/browser/indexer is CompuPic, available from
ftp.photodex.com:/cpic32.exe (Windows 95, NT, or 3.1+Win32s) or
ftp.photodex.com:/cpic.exe (Windows 3.1).  Shareware, $40.

Many people like Paint Shop Pro.  It's overkill as just a JPEG viewer
(especially since image quality is not very good on 8-bit displays), but
as an image editor and manipulator it is very strong.  Current version is
4.1 for Windows 95 and Windows NT 4.0; an older version is still available
for Windows 3.1.  Available from http://www.jasc.com.  Shareware, $69.

WinJPEG displays and converts JPEG, GIF, TIFF, BMP, and other file formats.
It has some other nifty features including screen capture, color-balance
adjustment, and slideshow.  Shareware, $25.  The current version is 2.76,
available from ftp.coast.net:/coast/win3/graphics/winjp276.zip.  (This is a
286-compatible version; if you register, you'll get the 386-and-up version,
which is roughly twice as fast.)

WinECJ is a fast, no-frills viewer with image quality noticeably worse than
most other JPEG viewers.  (You can purchase a version with better image
quality for AUD$30.)  Version 1.2 is free and available from
ftp.coast.net:/coast/win3/graphics/winecj12.zip.  Requires Windows 3.1 and
256-or-more-colors mode.

QPV and DVPEG (see previous section) work under Windows, but only in
full-screen mode, not in a window.  Also note that you can run the DOS
conversion programs described earlier inside a Windows DOS window.

Photoshop 4.0 supports progressive JPEG.  If you have an older version,
you can get a plugin that enables progressive JPEG loading and saving from
Pegasus, http://www.jpg.com/.  The plugin is free for loading, shareware
($29) for saving.

Other Windows 95 native releases include:
* PolyView.  Reads JPEG, PNG, GIF, BMP, Photo-CD.  Current version is 2.21,
  available from ftp.winsite.com:/pub/pc/win95/desktop/polyv221.zip.
  Shareware, $20.

Other popular Windows NT-only viewers include:
* NTj.  Reads JPEG, GIF, and BMP.  Available from
  ftp.digital.com:/pub/DEC/NTj/NTj-x86.exe (or NTj.exe for the DEC Alpha
  version).  Freeware.
* PolyView.  Reads JPEG, GIF, BMP, Photo-CD.  Current version is 1.70,
  available from ftp.winsite.com:/pub/pc/winnt/misc/polyv170.zip.
  Shareware, $20.

TwistedPixel, an OCX component that reads and writes JPEG and other formats
(and also does many other kinds of image manipulations), is available at
http://home.earthlink.net/~bananasoft/TWISTED.HTM.  OCXs are usable by
Visual Basic, Delphi, and other non-C programs.  Shareware, $69.  Requires
Windows 95 or NT.

------------------------------

Subject: [7] OS/2

The most widely used OS/2 JPEG viewers are:

PMJPEG 1.73: OS/2 2.x port of WinJPEG, a popular viewer/converter for
Windows (see description in previous section).  Shareware, $20.  Available
from hobbes.nmsu.edu:/os2/graphics/pmjpg173.zip.

PMView 0.92: JPEG/GIF/BMP/Targa/etc viewer.  GIF viewing very fast, JPEG
viewing roughly the same speed as the above two programs.  Has image
manipulation & slideshow functions.  Shareware, $35.  Available from
hobbes.nmsu.edu:/os2/graphics/pmview92.zip.

Galleria 2.2:  JPEG/BMP/PCX/Targa/TIFF viewer/editor/converter.
Shareware, $65.  Available from hobbes.nmsu.edu:/os2/graphics/galler22.zip.

All of these viewers require Palette Manager for best display quality.
Opinion seems to be about equally split as to which is the best, so try
them all to see which one you like.

JPEGPROC enables all OS/2 multimedia applications to read and write JPEG
files.  Available as part of the "Practice Viewer Upgrade" which also
includes a multimedia browser alleged to be better than IB.EXE.
Shareware.  Available from hobbes.nmsu.edu:/os2/graphics/pvu110.zip.

Very out-of-date OS/2 executables of the free IJG conversion programs
are available from hobbes.nmsu.edu:/os2/graphics/jpegv4.zip (32-bit) or
hobbes.nmsu.edu:/os2/graphics/jpeg4_16.zip (16-bit, for OS/2 1.x).
I hope someone will submit newer versions soon.

Note: the hobbes OS/2 collection is mirrored at ftp-os2.cdrom.com.

------------------------------

Subject: [8] Macintosh

Most Mac JPEG programs rely on Apple's JPEG implementation, which is part of
the QuickTime system extension; so you need to have QuickTime installed.
To use QuickTime, you need a 68020 or better CPU and you need to be running
System 6.0.7 or later.  (If you're running System 6, you must also install
the 32-bit QuickDraw extension; in System 7, that is built in.)  The latest
version of QuickTime is 2.5, available from http://quicktime.apple.com/.

Mac users should keep in mind that QuickTime's JPEG format, PICT/JPEG, is
not the same as the Usenet-standard JFIF JPEG format.  (See part 1 for
details.)  If you post images on Usenet, make sure they are in JFIF format.
Most of the programs mentioned here can handle either format.

Another thing to be aware of is that QuickTime still does not handle
progressive JPEG, so Mac programs won't either unless they include their
own JPEG code.  Most of the programs suggested here do.

The two major Internet sites for Mac software are sumex-aim.stanford.edu and
mac.archive.umich.edu.  Unfortunately they are both very busy, so you may
have better luck getting files from a mirror site.  (In fact, these days
you *must* use a mirror site for sumex-aim; the primary archive only allows
mirror sites to log in!  The sumex-aim FTP pointers given below are
therefore useless as-is; you *must* substitute a mirror site name.)  See
"Introductory Macintosh Frequently Asked Questions" in the comp.sys.mac.*
newsgroups for the current locations of mirrors.

JPEGView is an excellent free program for viewing JFIF,PICT/JPEG,GIF,TIFF,
and other image files.  It can convert between the two JPEG formats and can
create preview images for files.  The current version is 3.3.1, available
from sumex-aim.stanford.edu:/info-mac/gst/grf/jpeg-view-331.hqx.  Requires
System 7; QuickTime is optional.  JPEGView is a fine viewer with an unusual
but well-thought-out design (no scroll bars, for example).  Unfortunately,
it hasn't been updated in a long time, and is starting to show its age.
There are reports of bugs under System 7.5.3, and it doesn't handle
progressive JPEG.

Jade is a new, very promising freeware viewer for JPEG, GIF, PICT, and
BMP images.  It's fast, simple to use, and has preview and slideshow
capabilities.  And it supports progressive JPEGs.  Since JPEGView is no
longer being updated, Jade will probably supersede it as the most popular
free Mac JPEG viewer before long.  Current version is 1.2, available from
sumex-aim.stanford.edu:/info-mac/gst/grf/jade-12.hqx.  Requires 68020
(or higher) or PowerPC, as well as System 7.5 (or later) or Thread Manager.

GIFConverter, a shareware ($40) image viewer/editor/converter, supports
JFIF,PICT/JPEG,GIF, and many other image formats.  Current release is 2.3.7,
mac.archive.umich.edu:/mac/graphics/graphicsutil/gifconverter2.37.cpt.hqx.
Newer beta versions are available at http://www.kamit.com/gifconverter.html.
Requires System 6.0.5 or later.  GIFConverter is not better than JPEGView as
a plain JPEG/GIF viewer, but it has much more extensive image manipulation
and format conversion capabilities.  Also, GIFConverter is your best bet
if your machine is too old to run System 7 and/or QuickTime.  Hint: if
GIFConverter runs out of memory while loading a large JPEG, try converting
the file to GIF with JPEG Convert, then viewing the GIF version.

GraphicConverter is another popular viewer/editor/converter.  It has even
more functionality than GIFConverter, but is correspondingly larger.  Great
if you like lots of options.  Shareware, $35.  Current version is 2.5,
sumex-aim.stanford.edu:/info-mac/gst/grf/graphic-converter-25.hqx.

Sam Bushell has prepared a couple of simple but nicely done drag-and-drop
converter applications, "To JPEG" and "Progressify".  To JPEG converts any
file format understood by QuickTime to regular or progressive JPEG;
Progressify converts losslessly between regular and progressive JPEG
formats.  Both are free and require System 7.0 or later.  Available from
sumex-aim.stanford.edu:/info-mac/gst/grf/to-jpeg-10.hqx and
sumex-aim.stanford.edu:/info-mac/gst/grf/progressify-10.hqx.

If you are still running a pre-7.0 system, another freeware alternative is
JPEG Convert, a Mac version of the IJG JPEG conversion utilities.  It's too
old to know about progressive JPEG, so I don't recommend it unless you can't
run any of the above choices.  Runs on any Mac, available from
sumex-aim.stanford.edu:/info-mac/gst/grf/jpeg-convert-10.hqx.

Photoshop 4.0 supports progressive JPEG.  If you have an older version,
you can get two different plugins that enable progressive JPEG support
(they also work in other applications that support Photoshop plugins).
One is ProJPEG, available from ftp.boxtopsoft.com:/pub/ProJPEGv2.1.sit.hqx
(shareware, $25).  The other is JPEG Transmogrifier's plugin version,
available from ftp.best.com:/pub/gyld/plugin.sea.hqx (shareware, $22).
ProJPEG is worthwhile even with PS 4.0, because it has a nifty preview
of the results of different compression settings.

HINT: You must set the file type code of a downloaded JPEG file to 'JPEG'
to allow Photoshop to recognize it.  Most of the other programs suggested
here are not so picky about file type codes.

HINT: if you use Fetch to retrieve files by FTP, make sure ".jpg" is in its
list of binary file types under Customize/Suffix Mapping.  Otherwise Fetch's
"automatic" retrieval mode will retrieve JPEGs in text mode, thus corrupting
the data.  Old versions of Fetch do not include ".jpg" in the default list.
Also, Fetch 3.0 is buggy; get 3.0.1.

------------------------------

Subject: [9] Amiga

Most programs listed in this section are available from "AmiNet" archive
sites.  The master AmiNet site is wuarchive.wustl.edu, but there are many
mirror sites and you should try to use the closest one.

Osma Ahvenlampi posted a good review of Amiga picture viewers in
comp.sys.amiga.reviews in March 1994.  You can retrieve it from
math.uh.edu:/pub/Amiga/comp.sys.amiga.reviews/software/graphics/PictureViewerSurvey_2.
Opinions here are mostly stolen from his article.

CyberShow is a well-regarded viewer and converter for many image
formats including JPEG.  It can do truecolor/highcolor display with
CyberGraphics software and a suitable graphics board.  Shareware, $25.
Version 7.5 is available as a demo (displays grayscale only) from AmiNet
sites, /pub/aminet/gfx/board/cybershow75.lha.  Requires OS3.0 or better.

FastView is a fast, high-quality JPEG/GIF/ILBM viewer.  Works well on both
ECS and AGA displays.  Shareware, $15; requires OS 2.0.  Version 2.0 is
available from Aminet sites, file /pub/aminet/gfx/show/FView20.lha.

FastJPEG is a free JPEG viewer; it's fast and has good image quality, but it
doesn't view any formats except JPEG.  Somewhat faster than FastView on ECS
machines, slower on AGA.  Version 1.10 is available from Aminet sites, file
/pub/aminet/gfx/show/FastJPEG_1.10.lha.

HamLab Plus is an excellent JPEG viewer/converter, as well as being a
general image manipulation tool.  It's cheap (shareware, $20) and can read
several formats besides JPEG.  The current version is 2.0.8.  A demo version
is available from AmiNet sites, file /pub/aminet/gfx/edit/hamlab208d.lha.
The demo version will crop images larger than 512x512, but it is otherwise
fully functional.

PPShow is a good free JPEG/GIF/ILBM/ANIM/Datatype viewer.  Version 4.0 is
available from Aminet sites, file /pub/aminet/gfx/show/PPShow40.lha.  For
viewing JPEGs it is a little slower than FastJPEG, and image quality is not
as good (particularly on ECS machines).

Rend24 (shareware, $30) is an image renderer that can display JPEG, ILBM,
and GIF images.  The program can be used to create animations, even
capturing frames on-the-fly from rendering packages like Lightwave.
The current version is 1.05, available from AmiNet sites, file
/pub/aminet/gfx/aga/rend105.lha.

Viewtek is a free JPEG/ILBM/GIF/ANIM viewer.  The current version is 2.1,
available from AmiNet sites, file /pub/aminet/gfx/show/ViewTEK21.lha.
Viewtek used to be the best free JPEG viewer for Amiga, but it now faces
stiff competition.  The choice depends on your display hardware and personal
preferences.  Viewtek has poor display quality on OCS/ECS (HAM6) screens;
but it looks very good on AGA (HAM8).

Visage is a free JPEG/ILBM/PNG/Datatypes viewer with lots of features,
including progressive JPEG support (it even does progressive rendering).
Requires OS3.0 or better.  Version 39.14 is available from Aminet sites,
file /pub/aminet/gfx/show/Visage.lha.

There is finally a good JPEG datatype for use with datatype-based viewers
(such as Multiview or ShowDT).  Available from AmiNet sites, file
/pub/aminet/util/dtype/jfif_dtc.lha.  (The version dated 12/12/94
has a bug; you should also get /pub/aminet/util/dtype/jfif_FIX.lha.)

A newer JPEG datatype is now available that supports progressive JPEG.
See AmiNet sites, file /pub/aminet/util/dtype/akJFIF43x.lha.  Shareware.

The free IJG JPEG software is available compiled for Amigas from AmiNet
sites, file /pub/aminet/gfx/conv/jpegV6bin.lha.  (Despite the name, this
is now version 6a.)  These programs convert JPEG to/from PPM, GIF, BMP,
Targa formats.

If you have a DCTV box or a compatible display, try JPEGonDCTV.  Available
from AmiNet sites, file /pub/aminet/gfx/show/JPEGonDCTV100.lha.  Viewtek is
also reported to work well with DCTV.

------------------------------

Subject: [10] Atari ST

GEM-View (shareware, $26) displays JPEG, GIF, and other image formats.
FTP from atari.archive.umich.edu:/atari/Graphics/Gemview/gview248.lzh.
This is a well regarded viewer.  The English documentation tends to be a
few versions behind, though.

MGIF is a good free viewer/editor for JPEG and many other image formats.
It's particularly good on monochrome monitors, where it manages to achieve
four-level gray-scale effect by flickering; but it works on all Ataris.
Version 5.00 is at atari.archive.umich.edu:/atari/Graphics/mgif500.lzh.

1stGuide is a small, fast viewer for all ST/TT/Falcon systems; it supports
JPEG, PNG, and other file formats.  Shareware, $35.  Available from
ftp.cs.tu-berlin.de:/pub/atari/View/1st-guide/1stguide.zip.

The free IJG JPEG software is available compiled for Atari ST/TT/etc
from micros.hensa.ac.uk:/micros/atari/tos/p/p108/jpeg5abn.zoo.
These programs convert JPEG to/from PPM, GIF, BMP, Targa formats.

------------------------------

Subject: [11] Acorn Archimedes

The Acorn archive at micros.hensa.ac.uk contains several JPEG-capable
programs.  Read the file micros.hensa.ac.uk:/micros/arch/riscos/index
for retrieval instructions.  Recommended archive entries include:

a022 Translator 7.18: image file format converter (shareware)
b008 FYEO 2.02: For Your Eyes Only, fast JPEG/GIF image viewer (shareware)
a110 JPEG 6.a: IJG v6a software (JPEG<=>PPM,GIF,Targa) w/ desktop front end
a121 ChangeFSI 1.15: image format conversion and viewing
e018 SwiftJPEG 0.09: fast JPEG viewer, requires SpriteExtend 0.99

SpriteExtend 0.99 comes with ROS 3.6, and is available for ROS 3.5 from
ftp.acorn.co.uk:/pub/riscos/releases/spriteextend.arc.  It provides very
fast JPEG decoding, but sacrifices image quality on 256-color displays.

------------------------------

Subject: [12] NeXT

OmniImageFilter is a filter package that converts NeXTStep TIFF to and from
about 30 image formats.  It reads JPEG but does not write it.  It works with
most NeXTStep programs that handle drag-and-drop.  OmniImage is a simple
image viewer that uses the filter package.  Both are free.  Available from
ftp.omnigroup.com:/pub/software/OmniImageFilter-3.0.pkg.tar and
ftp.omnigroup.com:/pub/software/OmniImage-3.0.1.pkg.tar.

ImageViewer is a PD utility that displays images and can do some format
conversions.  The current version reads JPEG but does not write it.
ImageViewer is available from the NeXT archives at sonata.cc.purdue.edu and
cs.orst.edu:/pub/next/3.0/bin/ImageViewer0.9i.tar.Z.  Note that there
is an older version floating around that does not support JPEG.

The "imagetools" archive at ftp.thoughtport.com:/pub/next/graphics/ includes
NeXTStep compiled binaries for a wide array of free image manipulation tools
including the IJG JPEG tools.

NeXTStep includes built-in support for TIFF/JPEG, but not for the
Usenet-standard JFIF format.  Be warned that the TIFF/JPEG standard is
about to change away from the flavor currently produced by NeXTStep,
so compatibility with other platforms is doubtful.

------------------------------

Subject: [13] Tcl/Tk

Jan Nijtmans' "Img" package is a dynamically loadable Tcl/Tk extension that
adds full support for JPEG, PNG, and TIFF images to the Tk photo widget.
There are a number of incomplete JPEG Tk extensions floating around the net,
but this is the only one I'd recommend.  Version 1.1p1 is free and available
from ftp.nici.kun.nl:/pub/nici/software/tcltk/img/img1.1p1.tar.gz
(precompiled binary packages are in the same directory).  Works on Unix and
Windows; Mac port not done yet.

------------------------------

Subject: [14] Other systems

If you don't see what you want for your machine, check out the free IJG
source code described in the next section.  Assuming you have a C compiler
and at least a little knowledge of compiling C programs, you should be able
to prepare JPEG conversion programs from the source code.  You'll also need
a viewer program.  If your display is 8 bits or less, any GIF viewer will do
fine; if you have a display with more color capability, try to find a viewer
that can read Targa, BMP, or PPM 24-bit image files.

------------------------------

Subject: [15] Freely available source code for JPEG

Free, portable C code for JPEG compression is available from the Independent
JPEG Group.  Source code, documentation, and test files are included.
Version 6a is available from ftp.uu.net:/graphics/jpeg/jpegsrc.v6a.tar.gz.
If you are on a PC you may prefer ZIP archive format, which you can find at
ftp.simtel.net:/pub/simtelnet/msdos/graphics/jpegsr6a.zip (or at any
Simtel mirror site).  On CompuServe, see the Graphics Support forum
(GO CIS:GRAPHSUP), library 12 "JPEG Tools", file jpegsr6a.zip.

The IJG code includes a reusable JPEG compression/decompression library,
plus sample applications "cjpeg" and "djpeg", which perform conversion
between JPEG JFIF format and image files in PPM/PGM (PBMPLUS), GIF, BMP,
Utah RLE, and Targa formats.  A third application "jpegtran" provides
lossless transcoding between different JPEG formats --- for example, it can
convert a baseline JPEG file to an equivalent progressive JPEG file.  Two
small applications "wrjpgcom" and "rdjpgcom" insert and extract textual
comments in JFIF files.  The package is highly portable; it has been used
successfully on many machines ranging from Apple IIs to Crays.

The IJG code is free for both noncommercial and commercial use; only an
acknowledgement in your documentation is required to use it in a product.
(See the README file in the distribution for details.)

The IJG code has recently been translated into Pascal --- see
ftp.simtel.net:/pub/simtelnet/msdos/turbopas/pasjpg10.zip.  This version
has been tested under Turbo Pascal and Delphi, and it should be portable
to compatible Pascal compilers.


A different free JPEG implementation, written by the PVRG group at Stanford,
is available from havefun.stanford.edu:/pub/jpeg/JPEGv1.2.1.tar.Z.  The PVRG
code is designed for research and experimentation rather than production
use; it is slower, harder to use, and less portable than the IJG code, but
the PVRG code is easier to understand.  Also, the PVRG code supports (the
original form of) lossless JPEG, while the IJG code does not.  But PVRG does
not support progressive JPEG.

There's also a lossless-JPEG-only implementation available from Cornell,
ftp.cs.cornell.edu:/pub/multimed/ljpg.tar.Z.

Neither the PVRG nor Cornell codecs are being actively maintained, but the
IJG code is.

------------------------------

Subject: [16] Which programs support progressive JPEG?

With luck, this will only be a Frequently Asked Question for a short time,
after which most JPEG-supporting programs will have been upgraded to include
p-JPEG capability.  But right now it's a hot topic.  Here's the latest
I've heard (if you have newer info, please send mail):

WWW Browsers:

Netscape 2.0b1 (Unix/X, Windows, Mac, OS/2): full implementation

Spyglass Enhanced Mosaic 2.1 (Unix/X, Windows, Mac): full implementation
(Note: lots of other people license Spyglass' code, but I don't know
which licensees are shipping the latest version.)

Netshark 1.1 (Windows, Mac): full implementation

Microsoft Internet Explorer 2.0 (Windows, Mac): full implementation

Java 1.0 (Windows 95/NT, Solaris, more coming): full implementation

OmniWeb 2.0 (NeXTStep): full implementation

Wollongong's Emissary 1.1 (Windows): full implementation (? not sure)

I-Comm 1.09beta (Windows): full implementation (?)

UdiWWW 1.0.010 (Windows): full implementation

NCSA Mac Mosaic 3.0a2 (Mac): full implementation

NCSA Windows Mosaic 2.1.1 (Windows): reads p-JPEG, no incremental display

NCSA X Mosaic 2.7b2 (Unix/X): reads p-JPEG, no incremental display

Arena beta-1e (Unix/X): reads p-JPEG, no incremental display

Fresco 0.72 (Acorn): reads p-JPEG; full incremental display in Release II

(A browser that doesn't do incremental display of images won't be able to
give you the progressive effect, but it's still useful to have p-JPEG
compatibility so that you can at least see the image.)

See "BrowserWatch" at http://www.browserwatch.com/ for contact information
for these browsers.  Versions mentioned are the first to support p-JPEG,
not necessarily the current release.


Image Viewers & Converters:

See the appropriate prior sections for exact pointers to these programs.
Note that image viewers generally won't bother with doing incremental
display of p-JPEG files; they'll just read them in one pass for speed.

IJG command-line programs (almost any platform): see section 15 for source
code.  Precompiled executables are also available for some platforms;
see subject heading for your system.  You need v6 or later.

XV (Unix/X): recompile v3.10 with IJG v6 to read p-JPEG

ImageMagick (Unix/X): 3.6.6 or later

ACDSee95 (Windows 95/NT): 1.0 or later (no support in ACDSee for Win 3.1)

LView Pro (Windows 95/NT, or Win 3.1 + Win32s): 1.C or later

Paint Shop Pro (Windows 95/NT): 4.0 or later

PolyView (Windows 95): 2.18 or later

ThumbsPlus (Windows 95/NT, or Win 3.1 + Win32s): 3.0c or later

VuePrint (Windows): 5.0 or later

DISPLAY (DOS): 1.89 or later

SEA (DOS): 1.2b or later

JPEGPROC (OS/2): 1.1.0 or later

PMView (OS/2): 0.92 or later

Adobe Photoshop (Mac, Windows): 4.0 or later

Jade (Mac): all versions

GIFConverter (Mac): 2.4 or later

GraphicConverter (Mac): 2.3.1 or later

ProJPEG (Mac Photoshop plugin): all versions

JPEG Transmogrifier (Mac Photoshop plugin): all versions

DeBabelizer (Mac): 1.6.5 or later

akJFIF datatype (Amiga): 40.1 or later

CyberShow (Amiga): 7.1 or later

Visage (Amiga): 39.12 or later

1stGuide (Atari): 10.Jan.96 or later

------------------------------

Subject: [17] Where are FAQ lists archived?

Many FAQs are crossposted to news.answers.  Well-run netnews sites will have
the latest versions available in that newsgroup.  However, there are a *lot*
of postings in news.answers, and they can be hard to sort through.

The latest versions of news.answers postings are archived at rtfm.mit.edu.
You can retrieve this FAQ by FTP as rtfm.mit.edu:/pub/faqs/jpeg-faq/part1
and rtfm.mit.edu:/pub/faqs/jpeg-faq/part2.  If you have no FTP access,
send e-mail to [e-mail] containing the lines
    send faqs/jpeg-faq/part1
    send faqs/jpeg-faq/part2
(If you don't get a reply, the server may be misreading your return address;
add a line such as "path myname@mysite" to specify your correct e-mail
address to reply to.)  For more info about the FAQ archive, retrieve the
file rtfm.mit.edu:/pub/faqs/news-answers/introduction.

The same FAQs are also available from several places on the World Wide Web,
of which my favorite is http://www.faqs.org/faqs/.
This FAQ is http://www.faqs.org/faqs/jpeg-faq/.
Other popular WWW FAQ archives include http://www.cs.ruu.nl/cgi-bin/faqwais
and http://www.lib.ox.ac.uk/internet/news/.

--
            tom lane
            organizer, Independent JPEG Group
            [e-mail] or [e-mail]