White images with 'imshow'

[John W. Eaton]

On 26-May-2009, Søren Hauberg wrote:

| 2) I think it's true that very few (if any) are actively using the
|    Octave image format. So, perhaps we should convert the default image
|    ("default.img") into a png image?

It would be fine with me.  I tried

  [im, map] = imread ("default.img");
  imwrite (im, map, "default.png")

but it failed with

error: Magick++ exception: Magick: Color argument is invalid reported by Exception.cpp:272 (throwExceptionExplicit)
error: called from:
error:   /home/jwe/src/octave/scripts/image/imwrite.m at line 148, column 7

What's the right way to do the conversion?  Is there something wrong
with the way IM and MAP are returned from imread?  They work with
imshow now, so I don't know why imwrite should fail to accept them as
well.

jwe