Re: [Gimp-developer] Re: [CinePaint-dev] GIMP GBR format spec
On Thu, Jul 10, 2003 at 04:08:21PM +0200, Sven Neumann [EMAIL PROTECTED] wrote: in such an approach and I am sure that not many XML parsers will like CDATA blocks of several megabytes. _all_ xml parsers cope with cdata blocks of several megabytes. -- -==- | ==-- _ | ---==---(_)__ __ __ Marc Lehmann +-- --==---/ / _ \/ // /\ \/ / [EMAIL PROTECTED] |e| -=/_/_//_/\_,_/ /_/\_\ XX11-RIPE --+ The choice of a GNU generation | | ___ Gimp-developer mailing list [EMAIL PROTECTED] http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-developer
Re: [Gimp-developer] Re: [CinePaint-dev] GIMP GBR format spec
At 12:04 PM +0200 7/11/03, Marc wrote: On Thu, Jul 10, 2003 at 04:08:21PM +0200, Sven Neumann [EMAIL PROTECTED] wrote: in such an approach and I am sure that not many XML parsers will like CDATA blocks of several megabytes. _all_ xml parsers cope with cdata blocks of several megabytes. But the fact is that you're going to end up having to Base64 encode all the image data - which will blow the physical file size WAY out of proportion. And if don't do that (ie. attempt to leave in binary data), then you are violating the spirit of XML's design goals. Leonard -- --- Leonard Rosentholmailto:[EMAIL PROTECTED] http://www.lazerware.com ___ Gimp-developer mailing list [EMAIL PROTECTED] http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-developer
Re: [Gimp-developer] Re: [CinePaint-dev] GIMP GBR format spec
Hi, Leonard Rosenthol [EMAIL PROTECTED] writes: But the fact is that you're going to end up having to Base64 encode all the image data - which will blow the physical file size WAY out of proportion. And if don't do that (ie. attempt to leave in binary data), then you are violating the spirit of XML's design goals. That's why we dropped the idea of embedding the image data in XML. XML is very well suited to describe the structure of a multi-layered, multi-framed image/animation and it can be used perfectly to embed meta information as well as vector layers, paths and the like. XML namespaces make it easy to add application-specific extensions later. As you can see, the format I imagine here is not really GIMP specific. It could serve as a general exchange format for complex images. We discussed to bundle one XML file with a set of files that store the image data. These files would preferably be known image formats or perhaps even strict subsets of known image formats. That could be PNG for example but I'm not sure if PNG would suit our needs for higher bitdepths and the like. Most likely we will need a different format for the actual image data. I would suggest that these files are then put together in an ar archive. Such an uncompressed archive has the advantage that the XML metadata can easily be extracted. As you can see all this is very rough and not clearly layed out. It's a vague idea and it will need a lot of work to specify such a format in detail. Sven ___ Gimp-developer mailing list [EMAIL PROTECTED] http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-developer
Re: [Gimp-developer] Re: [CinePaint-dev] GIMP GBR format spec
On Fri, 11 Jul 2003, Leonard Rosenthol wrote: But the fact is that you're going to end up having to Base64 encode all the image data - which will blow the physical file size WAY out of proportion. And if don't do that (ie. attempt to leave in binary data), then you are violating the spirit of XML's design goals. Honestly I can't think of a way to put image data into a file format at all that wouldn't violate SGML's design goals. XML may differ in some aspects from SGML, but the fact is that SGML was designed to be a markup language for documents written in human languages, and the design decisions that created that also make storing binary in *ML cumbersome. GIMP needs a file format that is extensible, and a native representation for tree structures is essential, but there are plenty of ways to do this other than the XML method. Storing images, which ar almost all binary data, in true XML is a lesson in inefficiency. Oh wait, I take it back. I can think of a image format that retains the spirit of XML: gimpimage commentCreated by the GIMP!/commment layers colorspace=rgb bitdepth=8 layer width=6 height=6 row pixel r=127 g=127 b=127 / pixel r=127 g=127 b=127 / pixel r=127 g=127 b=127 / pixel r=127 g=127 b=127 / pixel r=127 g=127 b=127 / pixel r=127 g=127 b=127 / /row row . . . /row /layer /layers /gimpimage Determining whether this is a good format is left as an exercise to the reader. Rockwalrus ___ Gimp-developer mailing list [EMAIL PROTECTED] http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-developer
Re: [Gimp-developer] Re: [CinePaint-dev] GIMP GBR format spec
At 06:34 AM 7/11/2003 -0700, Nathan Carl Summers wrote: Oh wait, I take it back. I can think of a image format that retains the spirit of XML: gimpimage commentCreated by the GIMP!/commment layers colorspace=rgb bitdepth=8 layer width=6 height=6 row pixel r=127 g=127 b=127 / pixel r=127 g=127 b=127 / pixel r=127 g=127 b=127 / pixel r=127 g=127 b=127 / pixel r=127 g=127 b=127 / pixel r=127 g=127 b=127 / You know what is really scary about that... About 6 months ago, someone posted to the SVG mailing list a proposal for an XML-based raster image format that pretty much exactly that...And he was SERIOUS about it!!! Leonard ___ Gimp-developer mailing list [EMAIL PROTECTED] http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-developer
[Gimp-developer] Re: [CinePaint-dev] GIMP GBR format spec
David,
As a proposal for a modification which would bring back
compatibility, we could expand the header by 4 bytes to include
bit depth (8 or 16), which could then be factored into the load
routines of both our apps (we would crush 16 bit nbrushes down to
8 bits, and you would expand 8 bit brushes to 16 bits). As a file
format change, it would allow is backward compatibility, since
the format changes nothing in the other header fields.
We're open to that. However, until someone volunteers and sends us a patch,
we have no one ready to take that effort when our format is about to be
replaced anyway.
The GIMP Paintbrush File Format Version 2 (.gbr)
HEADER
--
Bytes 0 - 3: header_size:
Type: 32 bit unsigned int
Value: size of brush header (28) + length of brush name
Bytes 4 - 7: version
Type: 32 bit unsigned int
Value: The file format version. Currently
Bytes 8 - 11: width
Type: 32 bit unsigned int
Value: Brush width
Bytes 12 - 15: height
Type: 32 bit unsigned int
Value: Brush height
Bytes 16 - 19: bytes
Type: 32 bit unsigned int
Value: Colour depth of brush.
1 = greyscale, 4 = RGBA
Bytes 20 - 23: magic_number
Type: 32 bit unsigned int
Value: GIMP brush magic number.
('G' 24) + ('I' 16) + ('M' 8) + 'P'
Bytes 24 - 27: spacing
Type: 32 bit unsigned int
Value: Default spacing to be used for brush. Percentage
of brush width.
Bytes 28 - (header_size - 28):
Type: char *
Value: UTF-8 string - name of brush
BODY
Size: width * height * bytes
Type: uchar *
Value: Pixel values (row-first) for brush
Thanks, appreciate the docs!
To return the favor, enclosed is the spec for CPX that I posted in June. It
is so new it hasn't made it onto our web page docs yet. For clarification,
since my preliminary spec was rather terse, the data blob in CPX is a raw
write of the raster like the PPM P6 format. The CPX format was inspired by
the simplicity of PPM, but with the enhancement of XML tags. Like PPM, all
CPX tags are text but raster data is binary. See at the bottom below.
it would be incorrect to say that we don't identify our team.
I can clarify my meaning, although it seems a moot point. Some GIMP
developers are identified in internal documents within the source code, as
you correctly point out. However,when I asked for a list of developers on
the GIMP list I was told those documents were too inaccurate to be trusted.
It was suggested I could get the names of the GIMP developers by grepping
the check-in names from GIMP CVS -- which seemed a bit of bother -- but I
took the effort to do so anyway. I offered to give that list back to GIMP so
they could post a better public list of developer acknowledgements. The
response was that no new list should be posted by GIMP until it was perfect,
and that my list was inaccurate because Sven and others often check in
patches on behalf of others. I was also told my help wasn't needed.
FYI, using the best information I could gather, we have a list on our web
site recognizing the GIMP developers.
http://cinepaint.sourceforge.net/people/gimp.html
Cheers,
Robin
---
[EMAIL PROTECTED] Hollywood, California
www.CinePaint.org Free motion picture and still image editing software
- Original Message -
From: Robin Rowe [EMAIL PROTECTED]
To: [EMAIL PROTECTED]
Sent: Saturday, June 07, 2003 3:11 PM
Subject: [CinePaint-dev] cpx file type
Hi. Just FYI, creating a new image format called CPX (CinePaint XML).
This format will be similar in simplicity to PPM but more flexible using
XML
tags. Both spec and code will be made available.
A 640x480 8-bit image file example.cpx would be laid out something like
this:
CPX
IMG width=640 height=480 depth=8u raster=RGB compress=none bytes=921600
data=...[921,600 raw bytes]...
'depth' may be 8u|16u|16f-ilm|16f-rnh|32f
'raster' may be RGB|RGBA|RGBAZ or alternatively 'planes' with the same
choices
A lot more features could be added later. This is just to let everyone
know
this is in the works and coming maybe in July.
Cheers,
Robin
--
-
[EMAIL PROTECTED] Hollywood, California
www.CinePaint.org Free motion picture and still image editing software
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Re: [Gimp-developer] Re: [CinePaint-dev] GIMP GBR format spec
Sven Neumann wrote: We actually had something else in mind but since you don't seem to be interested I won't waste my time explaining our ideas. It is very sad to see that Sven thinks that Robin Rowe is the only person to whom his ideas should be told. Pity the rest of the GIMP developers (current and future) who might like to comment on it. Christopher ___ Gimp-developer mailing list [EMAIL PROTECTED] http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-developer
Re: [Gimp-developer] Re: [CinePaint-dev] GIMP GBR format spec
Hi, Christopher Curtis [EMAIL PROTECTED] writes: We actually had something else in mind but since you don't seem to be interested I won't waste my time explaining our ideas. It is very sad to see that Sven thinks that Robin Rowe is the only person to whom his ideas should be told. Pity the rest of the GIMP developers (current and future) who might like to comment on it. We will certainly write down more about this later but at the moment I focus on the release and on the developer conference. The ideas we had so far are quite rough but I will try to summarize them after the conference. I'm only willing to spend time on this right now if someone expresses actual interest. Sven ___ Gimp-developer mailing list [EMAIL PROTECTED] http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-developer
