[gs-devel] Is 1-bit image interpolation disabled in HEAD?

[Ray Johnston]

Raph,

Just in case you were curious, this is what 6ai.ps looks like when
the interpolation is enabled.

I think we are better off as is (as you mentioned on IRC).

Regards,
Ray
__________________________________________________________________

Ray Johnston wrote:
> 
> Raph,
> 
> If I understand your question correctly, I think that we did this
> intentionally to prevent spurious dots from "spraying" around a
> bi-level image when the output device couldn't really handle
> shades of gray in a single pixel.
> 
> The relevant change was:
> 
> src/gxiscale.c: revision 1.6
> date: 2002/03/06 19:15:15;  author: ray;  state: Exp;  lines: +13 -4
> Fix: Prevent image interpolation if the target device has less
> than 4 bits per component. This prevents interpolation from
> causing 'noise' (stripes, shadows, etc.) in the output when the
> device is halftone dithered. SourceForge bug 525708 for Artifex
> customer #710.
> 
> This has been is all releases from 7.20 on.
> 
> Do you think we need to reinvestigate this change?
> 
> Regards,
> Ray
> ___________________________________________________________________
> 
> Raph Levien wrote:
> >
> > Hi all,
> >
> >    I note that 6ai.ps (attached) does not interpolate in 1 bit mono
> > renderings. I'm not sure whether this is a bug or a feature, but in
> > any case the change doesn't seem to be documented. Did we decide to
> > make this change, and, if so, is it documented somewhere?
> >
> > Raph
> >
> >   ------------------------------------------------------------------------
> >              Name: 6ai.ps
> >    6ai.ps    Type: Gvim File (application/postscript)
> >          Encoding: quoted-printable
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