[Pkg-gmagick-im-team] Bug#603097: no way to make real "black" and "white" jpg

[Nelson A. de Oliveira]

Hi!

On Wed, Nov 10, 2010 at 9:37 PM,  <jidanni at jidanni.org> wrote:
> wget http://upload.wikimedia.org/wikipedia/en/5/50/Munch_The_Scream_lithography.png
> None of these make the image only have two colors.
> convert -colors 2 Munch_The_Scream_lithography.png Munch_The_Scream_lithography.jpg
> convert -depth 1 Munch_The_Scream_lithography.png Munch_The_Scream_lithography.jpg
> convert -monochrome Munch_The_Scream_lithography.png Munch_The_Scream_lithography.jpg
> Even the latter which is documented to be only "black" and "white".
> Xli still reports 29 colors for all.

Isn't this behavior caused by the lossy JPEG compression, where the
colors are slightly changed (due to compression)?

Best regards,
Nelson