Version 4.2 of

JPEG - coder/decoder/viewer adapted for the Retina Gfx-Board
------------------------------------------------------------

(changes at the end of this file)

If you don't own a Retina graphics board, this
may just be a jpeg encoder/decoder for you.

Though RetinaDisplay is already able to display
JPEG pictures, here's a better alternative.

Included are two executables:

cjpeg  does JPEG-compression, just type
       cjpeg -h  for a short syntax summary.
       This program has just been adapted by
       me to use the multipic.library
       to read various picture formats

djpeg  does JPEG-decompression, and to this
       one I added the watch-directly-on-Retina
       feature, it's enabled by default.
       You may also try djpeg -h here.

Both programs are compiled from the official
"fourth public release of the Independent JPEG
Group's free JPEG software". Only djpeg has been
modified by me.

Why use djpeg instead of RetinaDisplay?

- djpeg is faster, it's even faster than most commercial
        jpeg-loaders available.
- djpeg lets you watch the picture while it's decoded
- djpeg supports more jpeg-derivatives
- djpeg supports 8-bit as well as 24-bit display on
        the retina board. Watching JPEGs with the
        -greyscale switch given is even faster.
- djpeg is able to do "color-quantization", that is,
        if you enable that feature by "-color 256",
        an 8-bit screen will be opened on the
        Retina, giving you the ability to watch even
        larger pictures than it may be possible
        in 24-bits.

REQUIREMENTS:

 You NEED to have IXEmul.library available, this library
 is part of Markus Wild's GNU C (2.3.3) port for the
 amiga. It's available from several ftp-servers.

NOTES:

 djpeg spits its output to standard I/O, unless
 you specify anything else with a redirection
 ("djpeg -targa bla.jpg >bla.targa")
 
 press CTRL-C when djpeg is finished to close the screen.

 I compiled a >=68020 and 68881 version, too, but there were
 no measurable speed-difference.


If anyone wants the source-code, he'd contact me via email,
my adress is lkv@mania.robin.de

The original JPEG V4 source is available from several ftp-servers.

Just enjoy it,

Lutz Vieweg


CHANGES:

4.2
    - oh no, sorry... the archive with 4.1 included
      the old 4.0 executables...
    - for consistency, CTRL-C is now used to abort
      djpeg in any case.

4.1 
    - now you can always stop djpeg with CTRL-C
      while decoding...
    - cjpeg changed: it uses now the multipic.library
      (supplied with the Retina Software 1.3 and up)
      to load the original picture, therefore any
      format supported by this library may be packed!
    - cjpeg now uses infile outfile syntax
      djpeg still writes on stdout by default.
    - cjpeg progess display enabled

 PERMSSN    UID  GID    PACKED    SIZE  RATIO     CRC       STAMP          NAME
---------- ----------- ------- ------- ------ ---------- ------------ -------------
[generic]                 2398    5002  47.9% -lh5- 780c Jan 25  1993 changelog
[generic]                18140   39516  45.9% -lh5- bbf4 Jun  6  1993 cjpeg
[generic]                26257   53912  48.7% -lh5- 7016 Jun  6  1993 djpeg
[generic]                 9285   25265  36.8% -lh5- 56b8 Nov 18  1992 libs/COPYING.LIB
[generic]                77035  148428  51.9% -lh5- 10da Dec 30  1992 libs/ixemul.library
[generic]                 3443    7838  43.9% -lh5- 0fc2 Jan 25  1993 man/cjpeg.1
[generic]                 2022    4520  44.7% -lh5- 4da7 Jan 25  1993 man/djpeg.1
[generic]                 9039   21128  42.8% -lh5- 93e9 Jan 25  1993 readme
[generic]                 1391    2829  49.2% -lh5- 1327 Jun  6  1993 RETINA.readme
[generic]                99326   99326 100.0% -lh0- 3d64 Jun  2  1993 TestImg.jpg
[generic]                 5934   14687  40.4% -lh5- 98c1 Jan 25  1993 usage
---------- ----------- ------- ------- ------ ---------- ------------ -------------
 Total        11 files  254270  422451  60.2%            Jun  6  1993