Indigo Resolution, Color and JLT

The basic issue for RIPing to or from a JLT file is that it contains multilple resolutions. The files contain two types of image values. A lo-res value and a special marker that includes an edge definition at 4x the resolutio of the lo-res value. There is a special code to indicate these edges.

There is an FTP folder called examples that contains an example job. There are three files: the original JLT, the JLT dumped from the Indigo, and the PDF I created from the original JLT.

If you zoom into the JayLight PDF (using Acrobat) you will see much denser pixels than on the JLT PDF dumped directly by the Indigo. The Indigo JLT dumper uses only the lo-res output - so fonts and other items in the image with fine strokes will not look good if imaged on anothe device.

The key for RIPing to and extracting from JLT files is to get the edge processing right.

You will notice that for the most part the left (as in left-to-right) edges look good, but the right edges don't. This is my bug and I am working on it now.

You will also notice that the file looks washed out - this is because the color values that are native in the file are within a compressed range (0..127) as opposed to (0..255). There are encoding/edge issues that interact with the color issues. While I have code to address this - the complete package is not quite sorted out so the washout will be present.