Re: Guile-CV: Not a GRAY, RGB nor an RGBA image "sand.tif"

[Mark H Weaver]

David Pirotte <address@hidden> writes:

> Hi Daniele,
>
>> > Yes: your are not in the right directory wrt guile, and this flename 'does 
>> > not
>> > exists', it does not exists in the directory your are trying to load this 
>> > image,
>> > see:
>> >
>> >         scheme@(guile-user)> (getcwd)
>> >         $5 = "/usr/alto/projects/guile-cv/images"  
>> 
>> unfortunately that's not the problem, I am in the right directory and
>> the image is there. I still get that error.
>
> This is impossible :), you think you are in the right directory, but you most
> likely you are not.

David, with all due respect, this last response to Daniele comes off as
very dismissive and presumptuous to me.

According to Wikipedia, TIFF supports image types other than GRAY, RGB,
and RGBA.  Baseline TIFF also supports bilevel and palette-color images,
and there are extensions that support CMYK, YCbCr, CIE L*a*b* and
others.

  https://en.wikipedia.org/wiki/TIFF#Image_types
  https://en.wikipedia.org/wiki/TIFF#Image_types_2

The error message "Not a GRAY, RGB nor an RGBA image" would seem to
indicate that the image Daniele is attempting to load is not supported
by the image loading library, or at least that this is a possibility.

Your personal experience might be that this message always indicates
"file not found", but perhaps that's because you've never tried to load
an unsupported TIFF variant.  I find it hard to believe that the
software developer who wrote this code would have written "Not a GRAY,
RGB nor an RGBA image" if it *always* meant "file not found".

Does that make sense?

    Regards,
      Mark