If the constraint of —quality is that it is always 0-100, then that is
going to be hard to map and would lead to confusion(i.e. All other
applications would use a different slider then oiio).  Is it possible to
make the quality slider more contextual to the compression rather then
normalizing it to always be 0-100?

On Tue, Sep 20, 2016 at 11:49 PM, Larry Gritz <l...@larrygritz.com> wrote:

> maketx doesn't have a --quality command at all, primarily because we'd
> traditionally been using either lossless TIFF or OpenEXR for textures, and
> for neither of those did quality come into play.
>
> But recently we added support for TIFF-with-jpeg, and OpenEXR with DWAA
> compression has since come along and looks useful, so if you think that a
> --quality flag for maketx is helpful, we can add it.
>
> The real problem is that quality is assumed to be 0-100, with 100 meaning
> lossless. It works well for JPEG, which is the prototypical example. But I
> wasn't sure how to make it map to the dwa compression level without being
> confusing (dwa compression is an open ended scale, and higher numbers mean
> more compression).
>
> I'm perfectly happy to entertain requests to change it, if there's
> consensus. For example, if somebody wants to propose an intuitive and
> helpful mapping of the 0-100 scale of Quality into the appropriate
> dwaCompressionLevel, I think that might be useful.
>
> As you've seen, you can set the compression levels for dwaa and dwab by
> setting the "openexr:dwaCompressionLevel" attribute. It's not hooked up to
> the "--quality" only because, ad just mentioned, it wasn't obvious how that
> mapping should work.
>
>
>
>
> > On Sep 20, 2016, at 3:11 PM, Deke Kincaid <dekekinc...@gmail.com> wrote:
> >
> > Hi Larry
> >
> > We are trying to compress EXR files in OIIO with dwaa/dwab compression
> but currently this does not seem to directly hooked up to the --quality
> flag in oiiotool.  No matter if you use --quality 10 or 100, the attr
> dwaCompressionLevel key never gets set and the file is exactly the same
> size.
> >
> > We found that we need to directly set the attr via:
> > oiiotool blah.exr --ch R,G,B --croptofull --compression dwaa --attrib
> dwaCompressionLevel 100.0 -o blah_dwa.exr
> >
> > Any chance we could get this attr hooked up to the quality slider?  Also
> it appears that maketx does not have a --quality flag either (I haven't
> checked iconvert).
> >
> > -deke
> >
> >
> > _______________________________________________
> > Oiio-dev mailing list
> > Oiio-dev@lists.openimageio.org
> > http://lists.openimageio.org/listinfo.cgi/oiio-dev-openimageio.org
>
> --
> Larry Gritz
> l...@larrygritz.com
>
>
> _______________________________________________
> Oiio-dev mailing list
> Oiio-dev@lists.openimageio.org
> http://lists.openimageio.org/listinfo.cgi/oiio-dev-openimageio.org
>
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