python image library making dotty gifs

[Alex Hunsley]

Alex Hunsley wrote:

> I'm using python image library 1.1.4 
> (http://www.pythonware.com/products/pil/) to plot images.
> However, when I save an image to a gif file, it comes out very 
> dotty/ithered looking, even if it's a picture consisting only of one 
> colour!
> 
> Here's some example code that produces a dotty gif:
> 
> #!/usr/bin/python
> 
> # pymand joy!
> 
> import Image
> import ImageDraw
> 
> 
> imageWidth=300
> imageHeight=300
> 
> im = Image.new("RGB", (imageWidth, imageHeight))
> 
> 
> draw = ImageDraw.Draw(im)
> for y in range (0,imageHeight):
>     for x in range (0, imageWidth):
>         draw.point((x, y), (128,128,128))
> 
> # saving as a gif comes out dotty/dithered looking!
> im.save("plotImage.gif", "GIF")
> 
> 
> you can see the output gif here:
> 
> http://ohmslaw.ogr.uk/plotImage.gif

sorry, duff link, should be .org.uk:

http://ohmslaw.org.uk/plotImage.gif