ftp.nice.ch/pub/next/unix/graphics/jpeg6.README

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>Newsgroups: comp.archives.msdos.announce
>From: "Tom Lane" <tgl@sss.pgh.pa.us>
>Date: Sat, 02 Sep 95 18:46:42 +0400
>Subject: jpegsrc6.zip/jpeg6.zip - JPEG compression/decompression
>Message-ID: <306985637@f218.n5020.z2.ftn>

I have uploaded to SimTel, the Coast to Coast Software Repository (tm),
(available by anonymous ftp from the primary mirror site ftp.coast.net
and the secondary mirrors of SimTel):

ftp://ftp.coast.net/SimTel/msdos/graphics/jpegsrc6.zip
ftp://ftp.coast.net/SimTel/msdos/graphics/jpeg6.zip
ftp://ftp.coast.net/SimTel/msdos/graphics/jpeg6386.zip

SimTel/msdos/graphics/
jpegsrc6.zip    Source code for JPEG compression/decompression
jpeg6.zip       Convert JPEG files to/from BMP,GIF,PPM,PGM,TGA
jpeg6386.zip    Faster version of jpeg6.zip for 386 or better

These files are source and DOS executables for release 6 of the
Independent JPEG Group's free JPEG image compression code.  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, 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 principal improvement in version 6 is support of progressive JPEG.
Progressive JPEG allows an image to be stored in multiple scans of
increasing quality.  The initial scan provides a low-resolution image in
very little storage space, typically perhaps 10% of the total file.
Additional scans improve the quality, with the final image being exactly
equivalent to a baseline JPEG file of the same quality setting.  The
total space required is about the same as for the equivalent baseline
JPEG file (or even a little less).

We expect that progressive JPEG will prove extremely popular on the
World Wide Web, and in any other situation where an image is to be
viewed as it is received over a slow communications link.  For images
for which JPEG is appropriate (photos and such), progressive JPEG far
surpasses interlaced GIF in both total transmission time and the visual
appearance of the image refinement sequence.

The new IJG library provides full support for performing progressive
display of an incoming file.  If an application does not require
progressive rendering, only recovery of the final image, then no changes
to IJG v5-using code are required: just recompile with the new library
to be able to read progressive-JPEG files.

jpeg6.zip is a "vanilla" version for any DOS machine.  jpeg6386.zip is
a faster 32-bit version; it will run only on 386 or better CPUs with at
least 1Mb extended or expanded memory.  Source code is provided in
jpegsrc6.zip.

jpegsrc6.zip, jpeg6.zip and jpeg6386.zip have replaced
jpgsrc5a.zip, jpg5a.zip and jpg5a386.zip respectively.

Please direct any questions about this software to jpeg-info@uunet.uu.net.

Free.  Uploaded by the principal author.

Tom Lane
organizer, Independent JPEG Group
tgl@sss.pgh.pa.us

These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.