<< Click to Display Table of Contents >> Navigation:  »No topics above this level« LZW considerations

LZW or not LZW ?

 

vpxPrint HTML automatically creates images when necessary: image insert but lines, rectangles, ellipses and barcodes too. These images are GIF formatted. The GIF images that you can see on WEB pages use commonly a LZW encoding algorithm. The GIF format is free, but the LZW compression algorithm is under license by UNISYS Corp.

 

The 4GL point of view: vpxPrint can create images with a LZW encoding method or with RLE compression algorithm.

The RLE method results in some bigger files but is free.

The RLE method is the vpxPrint default method used to create image files.

If you want to use the LZW method, you have to acquire a  license from Unisys Corp.

 

The use of <HTML-LZW=TRUE> tag makes however no assumption about this license agreement and it's of your own responsibility to use or not the LZW encoding method regarding your licensing agreement.

 

As we are not of UNISYS commercial staff, we can just recommend to use the RLE method or  to be licensed by UNISYS. It's a formal 4GL recommendation.