[CREATE] OpenRaster

[Kai-Uwe Behrmann]

Am 21.06.06, 10:29 +0200 schrieb Øyvind Kolås:

> The scope and aim for designing the format is unclear. I think the
> goal of the initial version of the format should be exchange of
> layered images. Extra bells and whistles, for efficienct or arcane
> features, that might be desireable to serialize the entire state of an
> application should not be part of the initial core standard.

Fine. A clear goal.

> I think that for a core standard, with few compositing operators and
> available layer effects, it should be possible to agree upon the
> desired output.
> 
> On 6/21/06, Boudewijn Rempt <boud at valdyas.org> wrote:
> > > * Image data should be stored in either PNG or "raw bits" - lossless
> > > formats that are easy to access.  PNG should be used for any data
> > > that which is compatible with it, and "raw bits" for anything that
> > > is
> > > not (eg. CMYK or Lab data, floating point, etc.)

> My rationale for wanting JPEG data is the ability to exchange
> compressed "preview" versions of a document, with the structure
> intact. This can be useful as example material for tutorials and
> similar, where download size matters. The biggest problem with JPEG is
> that it doesn't support an alpha channel. (this can be worked around
> by storing, and applying a layer mask).

As well fine.
 
> Reusing existing single layer raster formats for the layers have
> advantages. PNG is a good candidates since it supports RGB an
> grayscale, with and witthout alpha in 8 and 16bit and is widely
> supported. In my personal opionion OpenEXRs biggest problem is that
> the interface is based on C++.

The PNG dependency is a whistle. Maybe it sounds nice,
but leads away from your first goal to concentrate on the basics.


"raw bits" and inclusion of a optional JPEG preview bell gets my vote.

regards
Kai-Uwe Behrmann
                                + development for color management 
                                + imaging / panoramas
                                + email: ku.b at gmx.de
                                + http://www.behrmann.name