Last week we posted a series of news articles about Piranha Net, a somewhat controversial new lossy graphics compression format from Piranha Inc.

Senior News Editor John Farr received this note from Applelinks reader Mihael Weinreb:

Hi John,

Applelinks is great and a very useful source of info. With the current Piranha/JPEG debate going on, would it not be useful to your readers to expand the discussion and include Luratech? As far as I can see this compression technique works very well, but I have not undertaken tests, and there seems some scope for a cross -comparison between the three compression techniques.

Thanks and all the best

Matthew Weinreb

The compression format Mr. Weinreb refers to is the German firm Luratech's LuraWave, which uses "wavelet-based compression" to reduce file sizes while claiming to achieve better image quality than conventional methods such as JPEG and TIFF.

Since 1993, LuraTech has been working on developing better standards for the compression of image and document data at higher rates based on new wavelet-algorithms. Initially LuraTech's focus was to develop a compression scheme addressing the entire spectrum from real lossless to highest compression rates of 200:1 and more, while preserving acceptable image quality. These R&D efforts led to the new LuraWave image compression format , as well as to LuraDocument, a new document compression format.

According to Luratech, compared to the current standard lossy compression format, JPEG, the LuraWave product family delivers substantially higher image quality at the same compression rates while dramatically reducing the amount of data required to represent and store an image. LuraWave and LuraDocument products are offered in configurations for individuals, networked workgroups, the Internet, etc. across all platforms (Unix/Linux, Windows, Macintosh).

Images in the LuraWave format (.LWF) can be viewed over the Internet using the company's free LuraWave browser plug-ins.

LuraWave products are offered in configurations for individuals, networked workgroups, the Internet, etc. across all platforms (Unix/Linux, Windows, Mac). All digital images that are currently stored in standard formats, such as TIFF, BMP, PPM, JPEG, etc. can easily be converted into the LuraWave image format by employing the various LuraWave products available online as Plug-ins (for Adobe Photoshop, Jasc Paintshop Pro, Netscape and Microsoft Browsers, Cumulus, Macromedia Director), stand-alone solutions (LuraWave Studio) and software developer kits (C-SDK, OCX-SDK).

Luratech claims the following advantages for LuraWave:
• Full spectrum of compression schemes from lossless to lossy
• Ability for scaled image reconstruction:
-The whole image may be reconstructed only by small fractions of the compressed data source (e.g. by 1% [quick-look], 10%, 50% and so on)
• Valuable time savings:
-No more endless waiting while transmitting large images. The LuraWave tools compress the images efficiently for transmission in a fraction of the time transmitting the full size image would take.
• Higher security against transmission interruption or disturbance:
• Money savings:
- less disk space required; reduced transmission costs
• User selectable compression ratio:
- allows easy control of image quality. Simple select the compression ratio that is best for your image up to 200:1.
• Precise reconstruction of edges
• No blocking effects as you can expect from JPEG

I asked Keeper of the iBook's Mark Newhouse, who had commented on Piranha Net, to take a look at LuraWave. He reports:

Charles:

After briefly taking a look, and downloading the plug-in, this appears to be a better technology than Piranha, but I can't easily verify the compression ratio from their demo. It appears that a full resolution version is stored on the server, and the plug-in negotiates how much info is requested about the image, and displays the result in the browser. Since I am testing on a T1 connection at work, it is hard to tell if this provides any savings in download time. I'll have to try over dial-up at home this weekend.

However, the only reason I downloaded the plug-in was to look at the demo because you asked. I wouldn't take the time to do that otherwise. If these companies want their products to be adopted for widespread use, they need to create a compression technique that will work without a browser plug-in, or something that is so compelling (like Flash or png) that will cause users and browser-makers alike to download/distribute the plug-in, or write it into their code.

I'll let you know about the dial-up download time after I get a chance to check it at home.

Mark followed up with a second note:

Charles:

I took a look at the site from home and the download times did appear to be less when the image is compressed more, and the quality certainly goes down as the compression increases.

This is interesting technology. It appears that a single image is stored on the server, and then the plug-in negotiates the quality of the image that is displayed in the browser. In the demo on their site you can change the compression ratio, and the image updates itself. Because it all uses the same image, you don't get a change in image size (bytes-wise) to compare what a standard jpeg compression would do to the same image. so it is hard to do a side-by-side comparison of how big the image is. (Does any of this make sense?)

As I said before, because it necessitates a browser plug-in that must be downloaded and installed, there will need to be an extremely compelling reason before people will go through the hassle.

Mark Newhouse
Keeper of the iBook <http://homepage.mac.com/ibook_keeper/>
iBook, iMac, iBlog <http://homepage.mac.com/iblog/>

You can check LuraWave out for yourself at Luratech's demo page:
http://www.luratech.com/products/demos/lurawave/lecture/quality_e.html

Charles W. Moore

.

October 06, 2008