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Re: Different topic

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| Thanks, Mayayana. I don't know what DRM means.

   As Helmut said, it can mean digital rights management.
About as many people translate it as digital restriction
management, since that's what it is. "Digital rights
management" is misleading marketing. DRM doesn't grant
rights or manage rights. It restricts access. I guess it's a
lot like saying pro-life and pro-choice instead of the more
accurate anti-abortion and pro-abortion. People on both
sides of that issue will argue all day about why it's incorrect
and biased to call them what they are. The propagandist
euphemisms make both sides sound more moral and noble. :)

| My ebooks are html
| packaged in a lockable EXE. I'm looking into also doing same with PDFs.

  A lockable EXE? You mean like password protected? The LIT
file I downloaded is just a compressed file. The restriction part is
the encryption.

   You're doing that with software help manuals? I'm curious: Why do
they need to be locked? And why doesn't a CHM work? And...if
it's a restricted eBook, how do people read it? Do you ship your own
custom reader with your software? Then people get a password to
unlock the help...something like that?

   PDFs are an entirely different approach. The format is open
and available, but it's extremely complex. I once delved into
writing a PDF parser and gave up. It was just too much work.
PDFs themselves are not lockable. The restriction is just a flag
saved in the file. It only functions if the program that opens
the PDF checks the flag and acts accordingly. Most PDF software
does follow the flag's directive, but it doesn't have to. It's actually
an arbitrary crippling that could just as easily be done with any
file format. I suppose the only reason that PDF readers build in
"cripple-respect" is because Adobe started that tradition
by positioning PDF as an opaque digital object to transfer corproate
letterheads and magazine excerpts from the source to a remote
printer. In other words, PDFs (and to some extent DOCs) provided
the illusion of paper-like palpability to a business world accustomed
to being awash in official documents printed on paper. Yet the
PDF file itself actually has no restrictions. It's immutability based on
mutually agreed illusion. :)

  I've recompiled XPDF and SumatraPDF myself, to ignore the
restrictions flag. It only requires editing the code to not check the
flag. Both XPDF and Sumatra are OSS. I haven't made my code public
only because I wanted to respect the intentions of the OSS authors.

   The problem here, to my mind, is that
a lot of people put restrictions on their PDFs for no good reason.
If I download a PDF and want to read it, I usually want to translate
it to plain text because PDF format is a pain in the neck. It's designed
for printing, not for reading. On the other hand, if I print it I usually
want to print it as plain text, too, so as not to waste ink on pointless
page decoration. In most cases there's no reason for limitations in that
regard.

Examples:
 1)  A few years ago I was in a car accident and downloaded the report
form. It was a PDF. I had to fill out 3 copies. But the State of Mass.
had locked the file so that I couldn't edit it! I ended up doing 2
screen shots and filling in the form as a BMP in Paint Shop Pro. Then
I printed the BMPs. I'm guessing that someone in state gov't just
locked the PDF without thinking, with some vague notion that official
documents are too official to leave unlocked.

2) I have a blind friend who uses text-to-speech software. He sometimes
gets PDFs that are actually made up of scanned pages, saved in the
PDF as BMPs. He can use OCR software on the BMPs, but only if
he can take them out of the PDF. If the material in question is free
to the public then there's no reason for the BMPs to be locked in.

|
| I expect something like DsoFile.DLL is what AlJones is after since the
| files he's looking at are compound docs by structure.
|
   Yes, I guess that if that works it will provide an easy way to get the
"meta" file content. If it doesn't work it could be accessed directly.
Unfortunately, it looks like either method requires a dependency. DsoFile
is not a Windows system file. It would have to be added to one's software
install. Though it might be feasible to write VB code to do the same
thing. According to MS, DsoFile is just a wrapper for the IPropertyStorage
interface. There may be VB code for that around somewhere, like
at Eduardo Morcillo's website.

  I just looked at a LIT file to see what the compression method is.
7-ZIP calls it a CHM. Interesting. It also says an HXS is a CHM. So I guess
CHM format is a sort of class of file. Other than 7-ZIP I have no
idea what can open a CHM. Looking at it in a hex editor, both CHM and
LIT seem to consist of a large header that lists the files inside and the
compression type. Then at a further offset is the actual compressed data.
I'm guessing it's probably similar to CAB files, which typically use either
MSZIP or LZX compression. So parsing the file from VB would be a big
project. If it were me I'd look into IPropertyStorage, in hopes of getting
a compact, dependency-free and dependable method of accessing any
"metadata" that Microsoft has written. 

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Different topic AlJones <al@mywebhome.net> - 2011-05-05 15:32 -0500
  Re: Different topic GS <gs@somewhere.net> - 2011-05-06 01:22 -0400
    Re: Different topic AlJones <al@mywebhome.net> - 2011-05-06 11:45 -0500
      Re: Different topic Dee Earley <dee.earley@icode.co.uk> - 2011-05-09 11:45 +0100
        Re: Different topic Al Jones <al@nowhere.invalid> - 2011-05-09 11:07 -0500
          Re: Different topic Dee Earley <dee.earley@icode.co.uk> - 2011-05-09 18:38 +0100
  Re: Different topic "Mayayana" <mayayana@invalid.nospam> - 2011-05-06 09:18 -0400
    Re: Different topic AlJones <al@mywebhome.net> - 2011-05-06 11:41 -0500
    Re: Different topic GS <gs@somewhere.net> - 2011-05-06 19:55 -0400
      Re: Different topic AlJones <al@mywebhome.net> - 2011-05-06 19:23 -0500
        Re: Different topic GS <gs@somewhere.net> - 2011-05-06 20:42 -0400
          Re: Different topic AlJones <al@mywebhome.net> - 2011-05-07 11:27 -0500
      Re: Different topic "Mayayana" <mayayana@invalid.nospam> - 2011-05-06 23:45 -0400
        Re: Different topic GS <gs@somewhere.net> - 2011-05-07 03:03 -0400
          Re: Different topic Helmut_Meukel <Helmut_Meukel@bn-hof.invalid> - 2011-05-07 11:24 +0200
          Re: Different topic "Mayayana" <mayayana@invalid.nospam> - 2011-05-07 10:40 -0400
            Re: Different topic GS <gs@somewhere.net> - 2011-05-07 13:06 -0400
              Re: Different topic GS <gs@somewhere.net> - 2011-05-07 13:14 -0400
              Re: Different topic "Mayayana" <mayayana@invalid.nospam> - 2011-05-07 13:34 -0400

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