Re: IMREAD does not recognize image path

[Mike Miller]

On Sun, Jul 19, 2015 at 20:19:51 -0700, Byron Harding wrote:
> I would like to apologize to the Octave GNU team for posting incorrectly
> and also not emailing help list. I am new to such lists, I use gmail, and I
> just replied to the latest email. This time, I scrolled down and posted at
> bottom.

Thanks for adhering to our customs :)

> I am still having the same difficulties even after I removed Octave GNU and
> reinstalled from https://launchpad.net/~octave. I have sent "Mike Miller"
> an e-mail as well because I would like to resolve this issue.

I am subscribed to the Octave lists also, no need to mail me
individually (but of course you didn't know that, no problem).

> octave:21> I = imread('OSUHat.jpg');
> error: imread: invalid image file:
> /usr/lib/x86_64-linux-gnu/octave/3.8.2/oct/x86_64-pc-linux-gnu/__magick_read__.oct:
>  failed to load: 
> /usr/lib/x86_64-linux-gnu/octave/3.8.2/oct/x86_64-pc-linux-gnu/__magick_read__.oct:
>  undefined symbol: _ZN6Magick5ColorC1Ehhh

This verbatim error message is the relevant information, thanks for
providing it. Your earlier messages referred to a mix of different error
messages, so it was a bit hard to identify what was the real problem
originally.

This error indicates that Octave can't call a function in the
GraphicsMagick library which is responsible for reading and writing
image files.

The function name

  $ echo _ZN6Magick5ColorC1Ehhh | c++filt
  Magick::Color::Color(unsigned char, unsigned char, unsigned char)

tells us that Octave was compiled against a GraphicsMagick library with
support for 8-bit pixel depth, and that the GraphicsMagick library you
have installed is probably using a different pixel depth.

What version of GraphicsMagick do you have installed?

  $ ldd 
/usr/lib/x86_64-linux-gnu/octave/3.8.2/oct/x86_64-pc-linux-gnu/__magick_read__.oct
 | grep -i graphicsmagick
          libGraphicsMagick++.so.11 => /usr/lib/libGraphicsMagick++.so.11 
(0x00007fdd87fa9000)
          libGraphicsMagick.so.3 => /usr/lib/libGraphicsMagick.so.3 
(0x00007fdd87a63000)
  $ dpkg -S /usr/lib/libGraphicsMagick++.so.11
  libgraphicsmagick++11: /usr/lib/libGraphicsMagick++.so.11
  $ dpkg -l | grep graphicsmagick
  ii  graphicsmagick           1.3.21-1  amd64   collection of image processing 
tools
  ii  graphicsmagick-dbg       1.3.21-1  amd64   format-independent image 
processing - debugging symbo
  ii  libgraphicsmagick++1-dev 1.3.21-1  amd64   format-independent image 
processing - C++ development
  ii  libgraphicsmagick++11    1.3.21-1  amd64   format-independent image 
processing - C++ shared libr
  ii  libgraphicsmagick1-dev   1.3.21-1  amd64   format-independent image 
processing - C development f
  ii  libgraphicsmagick3       1.3.21-1  amd64   format-independent image 
processing - C shared librar

If you have installed GraphicsMagick from the official Ubuntu
repositories and it's giving you this error, then the Octave package you
installed from our PPA is wrong for your version of Ubuntu.

If you have installed GraphicsMagick from another PPA or from another
source, it's incompatible with the Octave build you are trying to use
and will need to be reverted.

Some of this information is on the wiki, feel free to add more
information to help people debug these types of problems in the future.

http://wiki.octave.org/GraphicsMagick

-- 
mike