[Octave-bug-tracker] [bug #33612] Imread returns slightly different values than MATLAB

[Andrew Dougherty]

URL:
  <http://savannah.gnu.org/bugs/?33612>

                 Summary: Imread returns slightly different values than MATLAB
                 Project: GNU Octave
            Submitted by: adougher
            Submitted on: Tue 21 Jun 2011 07:22:28 PM GMT
                Category: None
                Severity: 3 - Normal
                Priority: 5 - Normal
              Item Group: Incorrect Result
                  Status: None
             Assigned to: None
         Originator Name: Andrew Dougherty
        Originator Email: 
             Open/Closed: Open
         Discussion Lock: Any
                 Release: 3.4.0
        Operating System: Microsoft Windows

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Details:

in Cygwin 1.7.9 (a recent fresh install including Octave 3.4.0 and
GraphicMagick-1.3.12)

Running the following using the first attached file:


M=imread('cars.jpeg');
M(1:10,1:10)


in both Octave and MATLAB(7.10.0.499 (R2010a)) produces 


ans =

  99  73  53  46  38  41  50  50  50  49
  88  73  58  52  49  49  49  46  48  48
  67  61  47  39  44  46  44  42  44  46
  58  55  35  19  26  34  34  38  40  42
  59  55  31  12  15  22  25  29  33  37
  37  32  21  10  12  17  18  20  26  29
  20  13  11  14  13  13  17  16  21  24
  28  16  18  24  16  13  14  12  18  20
  19  12  10  13  17  15  11  11  18  20
  18  12   8  13  16  14  13  13  19  21



ans =

   99   71   53   45   40   41   50   50   50   49
   88   71   58   52   49   49   49   46   48   48
   67   61   48   39   44   46   44   42   44   46
   58   55   35   19   26   33   34   37   39   42
   60   55   33   12   15   22   25   29   33   36
   37   32   21   10   12   16   18   20   26   29
   20   13   12   14   13   13   17   16   21   22
   28   16   18   24   16   13   14   11   18   20
   19   12   10   13   17   15   11   11   20   20
   18   11    8   13   16   14   13   13   19   21


Respectively.

These slight differences exist for other files I tested as well, but hopefully
this example will suffice in demonstrating the problem.




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File Attachments:


-------------------------------------------------------
Date: Tue 21 Jun 2011 07:22:28 PM GMT  Name: cars.jpg  Size: 35kB   By:
adougher

<http://savannah.gnu.org/bugs/download.php?file_id=23547>

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