bugGNU Octave - Bugs: bug #42474, saving jpg images with imwrite...


bug #42474: saving jpg images with imwrite changes image

Submitted by:  Ian Journeaux <ijourneaux>
Submitted on:  Sat 31 May 2014 04:12:34 PM UTC  
Category:  Octave Function Severity:  3 - Normal
Priority:  5 - Normal Item Group:  Regression
Status:  Duplicate Assigned to:  None
Originator Name:  ijourneaiux Open/Closed:  Closed
Release:  3.8.1 Operating System:  Any

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Wed 04 Feb 2015 04:04:32 AM UTC, comment #3: 

This bug is still present on the development branch.  It doesn't seem to be restricted to operating system either.  I just reproduced it on a Linux machine with a recent Mercurial tip.

I tested in 3.6.4 and it is a correct grayscale.

Rik <rik5>
Project Administrator
Mon 02 Jun 2014 03:16:54 PM UTC, comment #2: 

I started building MXE-Octave on a local machine. The problem saving to jpg exists with a recent build (June 1) of Octave.

Ian Journeaux <ijourneaux>
Mon 02 Jun 2014 01:33:57 PM UTC, comment #1: 

You mentioned on bug #41673 that it was working fine now?

Carnë Draug <carandraug>
Project Member
Sat 31 May 2014 04:12:34 PM UTC, original submission:  

Saving to jpg format is incorrect. here is a quick way to reproduce the error.

a = repmat (uint8 (0:255), 100, 1);
imwrite (a, "test.jpg");
imwrite (a, "test.fif");

The jpg image is incorrect while the tif image is correct.

I should have reported this some time ago.

Ian Journeaux <ijourneaux>


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    Follow 5 latest changes.

    Date Changed by Updated Field Previous Value => Replaced by
    2015-02-11 carandraug StatusConfirmed => Duplicate
        Open/ClosedOpen => Closed
        Dependencies- => Depends on bugs #41673
    2015-02-04 rik5 StatusNone => Confirmed
        Operating SystemMicrosoft Windows => Any

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