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JPEG 2000 incompatibility on Mac vs. PC

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John Faughnan

Mar 20, 2004, 9:38:18 AM3/20/04
subj: JPEG 2000 incompatibility on Mac vs. PC

I've downloaded some JP2 files to my iBook for testing. One I created
myself, using the LEAP plug-in with Photoshop Elements. Another I
downloaded from a test site.

In both cases when I opened the jp2 file on my iBook (OS X 10.3.2) I
saw only a black area (using the viewer app/quicktime). When I used
GraphicConverter 5.01 I saw the image. When I then saved the image
from GC as JPEG 2000 (jp2) it WAS viewable by QuickTime (Image Viewer,
iPhoto, etc).

Any idea what's up? I suspect it's a quirk in the file header.

I've been testing jpeg2000 compression of some scanned maps. This is a
great jpeg2000 application because there is a lot of text. JPEG does
poorly with text and edges, JPEG 2000's fractal compression does far
better. I can take a PNG image using JPEG 2000 from 16MB (PNG) to 1MB
(JP2) and still have every bit of line art and text be very clearly
readable. I can't do that with JPEG.


meta: jfaughnan, jgfaughnan, jpeg2000, Windows, OS X, Mac, Macintosh,
jp2, image, conversion, platform.

John Faughnan

Mar 20, 2004, 7:27:32 PM3/20/04
I tried another JPEG 2000 plug-in for Photoshop Elements/Mac. This one
opened the PC jp2 files and reported a "corrupted ICC file". So I
wonder if Macs have trouble reading the ICC file. It may take some
playing around to get a cross-platform JPEG2000 encoder.

Now I'm trying this one:

john (John Faughnan) wrote in message news:<>...


Mar 20, 2004, 9:21:34 PM3/20/04
In article <>, (John Faughnan) wrote:

We need FULL PNG support before anyone thinks about JPG 2000

Light travels faster than sound. People appear bright until you hear them speak.

John Faughnan

Mar 21, 2004, 9:18:36 PM3/21/04
Fnord is a keeper. See my blog for details:

Using the Fnord (free) Kakadu-based plug-in with PS Elements/PC I
created a jp2 file that opens without any trouble on my iBook. Since
QT (and Yahoo Messenger) also uses Taubman's Kakadu SDK this
compatibility is perhaps not surprising.

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