Yeah, I was going to say make it contextual -- so its basically an alias
for dwaCompressionLevel for the DWAA/B case.




On Wednesday, September 21, 2016, Deke Kincaid <dekekinc...@gmail.com
<javascript:_e(%7B%7D,'cvml','dekekinc...@gmail.com');>> wrote:

> 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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