Author Topic: Saved JPEG Files remain marked as "modified"  (Read 3124 times)

Offline Christoph Puetz

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Saved JPEG Files remain marked as "modified"
« on: 2013 March 18 09:44:04 »
Dear PI Community,
as I sometimes even process non-astronomical photos in PI, I found a litte flaw handling JPEG files.
This can easily be reproduced as follows:

1. Load any JPEG File
2. Modify it with any PI Process (i.e. ACDNR, ATW, ....)
3. Save it with CRTL-S or CTRL-Shift-S (or the File-Menu Entries)
4. If you close the window, you still get the message "The Image has been modified and is unsaved".

Nothing serious, but false  ;)

clear skies
christoph

Kind regards,
      Christoph
---
ATIK 383L+, Canon EOS 450d, modified,
Canon EOS 500d, 
20" Planewave CDK, 6" APO Starfire Refractor,
Celestron 8", Skywatcher ED80,
Peterberg Observatory (www.sternwarte-peterberg.de)
PixInsight, PHD-Guiding
private URL: www.ccdsky.eu

Offline pfile

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Re: Saved JPEG Files remain marked as "modified"
« Reply #1 on: 2013 March 18 09:58:13 »
juan will have to comment but since you have saved the file in a lossy format, one can argue that it has not really been saved. a compromised copy of the image has been saved instead...

Offline Juan Conejero

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Re: Saved JPEG Files remain marked as "modified"
« Reply #2 on: 2013 March 20 02:10:42 »
Rob has described it right. This is not a bug, but a feature of PixInsight. We call it strict file save mode. In strict mode, when a modified image is saved using a lossy compression scheme (such as JPEG) its modified state is not changed.

Strict file save mode is enabled by default. You can enable/disable it with Edit > Global Preferences > File I/O Settings.
Juan Conejero
PixInsight Development Team
http://pixinsight.com/

Offline Christoph Puetz

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Re: Saved JPEG Files remain marked as "modified"
« Reply #3 on: 2013 March 20 12:00:55 »
Juan und Rob,

thanks for the explanation!
Kind regards,
      Christoph
---
ATIK 383L+, Canon EOS 450d, modified,
Canon EOS 500d, 
20" Planewave CDK, 6" APO Starfire Refractor,
Celestron 8", Skywatcher ED80,
Peterberg Observatory (www.sternwarte-peterberg.de)
PixInsight, PHD-Guiding
private URL: www.ccdsky.eu