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Before PDF: John Warnock's 'Camelot'
Karl De Abrew writes: "In the Spring of 1991 Dr. John Warnock wrote a paper he
dubbed "Camelot" in which the Adobe Systems Co-founder and
CEO laid out the foundation for what has become Acrobat/PDF.
With the author's permission, Planet PDF is pleased to publish
the full-text of that historic document." Of course, now it's 2002, and the dream of universal display / printing remains only partly realized; PDFs really have helped to narrow the gap between dream and reality, though.
Especially when you consider that OSX now has a graphics engine based on PDF, which begins to finally close the gap between screen and paper ...
Gotta love those dreamy nerds.
; -- the corruption of government starts with its secrets. a truly free people keep no secrets. --
Another function of the IPS binder will be to include reconstituted fonts into the IPS file. The idea here is to include just the characters of a font that are actually used in the document. A result of including the necessary characters from the fonts used is that an IPS file will be completely self contained. In other words, when I send a file around the country, I don't have to worry about whether the receiving location has all the fonts required by the document. The current situation is that complex font substitution schemes are used to deal with locations not having the appropriate fonts.
Later on Adobe did better than this, with the Multiple Master Font idea --- even if a font or a subset of the font is not embedded (this can seriously bloat file sizes as the font encodings are a lot of overhead for a small document), Acrobat reader (or some other display device) can render the font pretty well because it knows how to "fake" the correct appearance based on similarities to combinations of master fonts. It's a very clever approach.
"Never bullshit a bullshitter" All That Jazz
Also while the pdf format is controlled by Adobe, the specs are open and available (contrast this with Microsoft's format which is a complete mystery), you can get the specs from Adobe's site and nothing prevents you from writing code that manipulates pdf files (well yes there are issues with compression algorithm).
This openess is the reason why Apple chose to use pdf as their graphic description language for OS X (older OS versions used QuickDraw). The windows page description language, is, I think, WMF. It's funny to think that the basic page description language used under Unix is Postscript, which is much more closed than PDF.
Previously this was available only though special software which had to be purchased from Adobe. Now the operating system emables me to create documents with the assurance that it will be rendered on anyone's screen as it would have been rendered by my printer.
Beyond that, I know anyone can print their own hard copy of my document without any cross-platform problems. That's something MS Word cannot boast.
Acrobat Pro allows you to edit PDFs, and with Ghostscript, you can edit PDFs and strip the "security" from encrypted PDFs leaving you with the original, 100% editable file.
PDFs are editable, you just need the right tools.
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I'll admit that I am no expert on PS, and know even less about PDF, but in what respect is PS "more closed" that PDF?! The whole language is publicly published and easily accessible for free to anyone near by a library. There are also countless implementations of PS interpreters.
Reality or nothing.
It has not been proposed because HTML is not a page description language. It's a document structuring language, even if a lot of people do not understand the difference. Its is simply the wrong tool. HTML displays a document using information about its structure (title, paragraphs), to an arbitrary media. A page description language is about describing precisely the graphical structure (x,y position of all elements).
Take a arbitrary page layout (say a magazine - a paper one), and ask yourself, can I describe this with HTML? The answer is no. HTML and PDF have different goals. Trying to use one for the other is not a good idea. Use the right tool.
A much better candidate would be the SVG format, which is based on XML, open and has all the needed features. It is a true vector graphic file format. The only problem is, it is not widely supported (and maybe the font embedding mechanism is not as good).
Then again, PDF does the job nicely -- and is widely supported. While you can embed proprietary features in PDF, so can you with an HTML file (simply by including a GIF file). In fact if you take the current HTML technology, as far as I know, the font embedding mechanism used for HTML is completly proprietary.
Maybe this issue is more complicated than Adobe = BAD Open Source = GOOD
As to why PDF has better compression that an compressed html page. The difference is that the compression is done inside the file, so each type of data is compressed with a different compression algorithm. Also PDF has a feature that is called object reuse, the basic idea is that if an element is present multiple time in a document, it will only be stored once (perfect compression if you want). If you design your html document carefully, you can get this, but more often, machine generated html is very redundant.
I'm no Adobe fan, but I've been working on PDF format for a few years and I found it great.
o cs/PDFRef.pdf
First, the filesize is ridiculous.
If you're comparing to plain text, yes. Otherwise, PDF have a built-in format that allows the producer to compress the PDF's streams (ie text and images) with a LZW algorithm.
They are in a closed format
These are java libraries for creating and editing PDFs :
pj[Open Source, GPL]
Big Faceless[Commercial w/ Evaluation]
retepPDF[Open Source, LGPL]
Java Pdf Library[Open Source, LGPL]
PDFGo[commercial]
rugPDF0.20[Open Source, LGPL]
By the way the closed format has an open specification : http://partners.adobe.com/asn/developer/acrosdk/d