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).