delorie.com/archives/browse.cgi   search  
Mail Archives: cygwin/2003/05/06/14:49:23

Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm
List-Subscribe: <mailto:cygwin-subscribe AT cygwin DOT com>
List-Archive: <http://sources.redhat.com/ml/cygwin/>
List-Post: <mailto:cygwin AT cygwin DOT com>
List-Help: <mailto:cygwin-help AT cygwin DOT com>, <http://sources.redhat.com/ml/#faqs>
Sender: cygwin-owner AT cygwin DOT com
Mail-Followup-To: cygwin AT cygwin DOT com
Delivered-To: mailing list cygwin AT cygwin DOT com
Message-ID: <014f01c313fe$b0692e90$6400a8c0@FoxtrotTech0001>
From: "Bill C. Riemers" <cygwin AT docbill DOT net>
To: =?iso-8859-15?Q?Jukka_Yl=F6nen?= <mail AT ylonen DOT info>, <cygwin AT cygwin DOT com>
References: <oproo6qcuklorcl2 AT mail DOT ylonen DOT info>
Subject: Re: Djvulibre testing
Date: Tue, 6 May 2003 14:38:24 -0400
MIME-Version: 1.0
X-Priority: 3
X-MSMail-Priority: Normal
X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1165

I would like to say I have an organized test plan, but I don't.  There is
none.  The most important things to test  are "c44", "cjb2", "cpaldjvu",
and "ddjvu".

c44 is for creating "DjVu" photos.  They are best compared to JPEG.  Usually
I compare with files produced by the "cjpeg" program.  Typically a DjVu
photo
of half the size appears about the same quality as the JPEG, but it does
depend
on the type of the photo.  The easiest option to use to control the size of
the
output is -size.  i.e.

   c44 -size 2048,4096,8192 foo.pnm foo.djvu

This would convert "foo.pnm" into a file of about 8k, divided in three
chunks so the file could begin displaying after the first 2k, update after
4k,
and finalize with the last 8k.

cjb2 is for creating bitonal images.  They are best compared with single
page tiff G4 files.  Typically, again you are looking at about 50% of the
size for the same quality.  i.e.

  cjb2 foo.pbm foo.djvu

cpaldjvu is for creating paletted images.  Best compared with GIF or PNG
images.  Size really varies.  Sometimes images are only 10% the size of the
PNG image, sometimes they are even larger than the original pnm image.

  cpaldjvu -colors 255 foo.pnm foo.djvu

ddjvu is for creating decoding the images back to pnm.  i.e.

  ddjvu foo.djvu foo.pnm

The rest of the commands are described in the "djvu" man page.  i.e.
    man djvu
You might find "djvm" and "djvmcvt" interesting for creating multipage
documents.  And of course "djview" is useful for viewing your DjVu document.
You can also use 'djview' to save out pnm files for use with the command
line programs.

If you are curious about the xml programs, try "man djvuxml".  It looks like
the command summary I had added to the "djvu" manual page for the xml
commands got clobbered in another update.  So, there is no existing overall
listing of what each of those commands do.

BTW.  About the speed problems.   Can you let me know your operating systems
particulars.  i.e. What version of Windows, CPU speed, RAM, ...  So, I can
check first off if I expect faster performance.  Perhaps I should try a
build
using "winthreads" instead of "pthreads" to see if that speeds things up.


                                            Bill



--
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple
Problem reports:       http://cygwin.com/problems.html
Documentation:         http://cygwin.com/docs.html
FAQ:                   http://cygwin.com/faq/

- Raw text -


  webmaster     delorie software   privacy  
  Copyright © 2019   by DJ Delorie     Updated Jul 2019