[pygtk] Displayed gtk.Image have fewer colors than the source pixbuf

[Stephen Langer]

How are you displaying the image?  Is it antialiased?

  -- Steve

On Jan 12, 2006, at 6:55 PM, Pontus Ekberg wrote:

> I am writing an image viewer that uses PyGTK. The displayed images do
> not look as good as expected though. When there should be soft
> transitions between colors I get stripes instead, as if the number of
> colors that can be displayed is limited to a relativly low number.
>
> For an example look at these two images.
>
> This is how it should look: http://home.student.uu.se/poek7897/ 
> nice.png
>
> This is how it is displayed: http://home.student.uu.se/poek7897/ 
> ugly.png
>
> I know there is nothing wrong with the pixbuf, for if I save it to a
> file right before I do the gtk.Image.set_from_pixbuf() it will have  
> all
> the colors intact.
>
> I figured there might be something I should do with  
> gtk.gdk.colormap or
> gtk.gdk.Visual, but I have tried everything I can think of with a few
> seg faults as the only results.
>
> I have also noticed that some other GTK image viewers have the exact
> same problem, while some others have not. I know some C programs with
> the problem and some without, but I have not found any in PyGTK that
> have solved it. Looking at the code for these C programs have not  
> given
> me any ideas though.
>
> Any ideas on the cause of this?
>
> Regards,
> Pontus Ekberg
> _______________________________________________
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> Read the PyGTK FAQ: http://www.async.com.br/faq/pygtk/
>

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