test message -- ignore

On Wed, Sep 21, 2016 at 2:50 PM, Jep Hill <jep...@gmail.com> wrote:

> I second the vote for #2
>
> On Sep 21, 2016, at 9:59 AM, Deke Kincaid <dekekinc...@gmail.com> wrote:
>
> I like #2.
>
> On Wed, Sep 21, 2016 at 9:36 AM, Larry Gritz <l...@imageworks.com> wrote:
>
>> So in following the spirit of OIIO's core mission to allow a single
>> generic API to shield users from the gory details of each individual format
>> (as much as possible), I feel strongly that --quality should not magically
>> change directions and scales for one format. If --quality 100 is "looks
>> perfect" and lower numbers mean "smaller files, bigger artifacts" for every
>> other format, it shouldn't be that for exr, 45 is perfect and larger
>> numbers mean smaller files. Also, it leads to confusing errors if you set
>> the "CompressionQuality" in an image metadata and then try to output it to
>> multiple files of different file formats.
>>
>> That's why quality is basically ignored for dwaa and instead you can set
>> the "openexr:dwaCompressionQuality" attribute -- it's possible to set
>> it, and the name communicates clearly that you are making a peculiar
>> format-specific adjustment (that will be ignored by other format writers,
>> if the same output is sent to a different file).
>>
>> OK, but I do see that this is awkward and verbose. So I'll propose two
>> alternatives, and am happy to go with whichever people want:
>>
>> 1. As Kevin points out, we can use something akin to Karl's mapping (I'll
>> find a cubic curve that maps these smoothly?) of quality's 0-100 scale into
>> settings for DWA compression quality. I don't know if that will give you a
>> "smooth" response either visually or in terms of file size. If somebody
>> wants to do a little research and try to map out a more perceptually or
>> size-wise linear response, please volunteer.
>>
>> 2. Another approach is to skip --quality, and just allow the compression
>> setting to be built into the compression name!  How does this look:
>> --compression dwaa:45 or --compression dwaa:200. The idea is that anything
>> starting with "dwaa" would turn on dwaa compression, and any optional
>> trailing numbers would set the dwaaCompressionQuality.
>>
>> Opinions?
>>
>>
>>
>> On Wed, Sep 21, 2016 at 8:15 AM, Deke Kincaid <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
>>>> >
>>>> >
>>>> > _______________________________________________
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>>>> > Oiio-dev@lists.openimageio.org
>>>> > http://lists.openimageio.org/listinfo.cgi/oiio-dev-openimageio.org
>>>>
>>>> --
>>>> Larry Gritz
>>>> l...@larrygritz.com
>>>>
>>>>
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>>>>
>>>
>>>
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>>
>>
>> --
>> Larry Gritz
>> l...@imageworks.com
>>
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>>
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-- 
Larry Gritz
l...@imageworks.com
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