[CREATE] OpenRaster

[Leonard Rosenthol]

At 04:29 AM 6/21/2006, Øyvind Kolås wrote:
>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.

         I agree 110%!!!!!!


>My rationale for wanting JPEG data is the ability to exchange
>compressed "preview" versions of a document, with the structure
>intact.

         As I noted in a previous message - I 
agree that JPEG for a preview/thumbnail image is 
just fine.  For not for actual layer data.


>The biggest problem with JPEG is that it doesn't support an alpha channel.

         True, but then the authoring application could choose PNG instead...


>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.

         The only other viable alternative is 
JPEG2000, which also supports CMYK and other 
colorspaces as well as better compression, 
etc.   Unfortunately, it is also harder to 
implement, heavier weight, and many consider it 
potentially patent encumbered - though there are 
some acceptable open source implementations.


Leonard

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Leonard Rosenthol                            <mailto:leonardr at pdfsages.com>
Chief Technical Officer                      <http://www.pdfsages.com>
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