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LizardTech's Distorted PDF - DjVu
Comparison An updated report by PlanetDjVu, March 18,
2003 For two
years now, LizardTech has maintained on their website a single comparative
example of PDF and DjVu, in the Business section of the Samples page, at:
http://www.lizardtech.com/solutions/document/samples/ This
"Annual Report" sample comparision is distorted, as the PDF file is
delibrately made 10 - 15 times larger than it should be, and the Fast Web
View feature of the PDF file is delibrately disabled.
 On the
basis of this example, a compression advantage ratio of 100:1 is claimed,
and this has long been the basis of marketing claims that DjVu compresses
100 times better than PDF.
We
reviewed this example in detail last June, and demonstrated that
the proper size of the PDF, when rendered correctly, is 15 MB, not 147 MB.
Nine months after our review, this comparision is not
corrected.
While DjVu
clearly enjoys compression advantages over PDF for scanned images and for
PDF that have a lot of color graphics, the compression advantages are at
best 10:1. This in itself is significant, we think.
We wonder
why LizardTech continues to offer this distorted comparison of DjVu to
PDF. The disabing of the Fast Web View feature of the PDF file forces the
entire file to be downloaded before it displayed, while when Fast Web View
is correctly enabled, Page 1 will be displayed while the remaining pages
download in the background.
We believe
that this distorted and false comparison is a dis-service to you, the
customer. If you will look into the Gallery of PlanetDjVu, you will find
many accurate and truthful comparisons of DjVu to PDF, on which to base
your informed decisions of which format to use in particular
circumstances.
When you
look at the other Samples on the LizardTech web page, open them and check
Document Properties, you will notice that most are in the OBSOLETE
Indirect DjVu format. These examples are the original ones provided by
AT&T when the format was acquired from LizardTech, and have since
become obsolete.
LizardTech
cannot even get something as simple as DjVu samples right, and this gives
us little confidence in them as a software company, sad to
say.
Adobe
would not and could not "get away" with such deceptive presentations. The
active PDF user community would be "all over them".
If we
wanted to at PlanetDjVu, we could easily make a DjVu file that was bloated
to 100 times larger than a PDF equivalent, but of course we do not want to
do this. We want to offer you truthful and honest and accurate
comparisons, as best as we can express it. You deserve no
less!
FYI -
Still looking for DjVuDigital samples and samples with
Annotations
The only
known examples of DjVu files on the web that were created with full PDF to
DjVu conversion process (transferring text as well as page images) can be
found at www.wentworthcourier.com.au.
The only
known example of a DjVu file created with the DjVu Virtual Print Driver
can be found here on the Forum Launch Page of
PlanetDjVu.
Why
LizardTech offers software for these flavors of DjVu but does not provide
examples on their website is beyond us!
We also
are looking for examples of the reported new annotation feature for DjVu,
but find none at the LizardTech website or elsewhere on the web. We
consider this feature to be "vaporware" until we can see an example
(seeing is believing).
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