"Transparency Handling" Option

As of PDF version 1.4 (equivalent to Acrobat Version 5.0) PDF documents can contain elements that are defined as transparent, known as transparency elements. Such transparent elements are created on several layers in the PDF, with some layers defined as being more or less "transparent". For certain cases, it is necessary to flatten these transparency elements to one layer.

You can enable the "Preserve Transparency" option in "Normalizing" of the "Qualify" sequence. We urgently recommend that you enable this option and set up transparency flattening at this point by enabling the "Transparency Handling" option.

"Transparency Flattening Quality" parameter

Use "Transparency Flattening Quality" to set how accurately flattening of the transparency elements to one layer will be. This affects solely the quality of characters and graphics that are converted to pixel data.

The default is 100 %, giving you the highest quality. We recommend that you keep this setting as it only minimally affects the file size of the results.

Note: Flattening to one layer may not be set up for jobs where trapping is used.

With the parameter "Compress generated images", you can choose a compression method to reduce the file size.

The following compression modes are available:

​•​JPEG 2000

"JPEG2000" is a further development of the JPEG (Joint Photographic Expert Group) ISO standard. A higher compression rate and a better quality than with the other compression methods is achieved through a different transformation method ("Wavelet") . Compression of images using JPEG 2000 takes quite a lot of time.

​•​JPEG (lossy)

JPEG is suited to grayscale and color images as well as photos with shades (blends). You can have loss of data with JPEG compression, for example, image data are removed and the image quality may be impaired.

Because JPEG compression removes image data, the compressed files are really noticeably smaller than the ZIP-compressed files.

​•​ZIP (lossless)

ZIP is well suited for images with large, single-color areas or repeat patterns, e.g. screen shots and simple images.

If JPEG 2000 or JPEG compression is selected you can specify the quality level for JPEG compression in the "Quality" box. The higher the quality (max. 100%), the lower is the compression rate and the larger the files.

For high quality images, you can select the ZIP compression.

"Transparency Flattening by Conversion to PostScript" option

For difficult cases that cannot be processed otherwise, you can convert the PDF files to PostScript with this option and convert them again to a PDF format with flattened transparency elements by refrying them. It is possible that this refrying process might repair difficult or faulty PDF files. Enable this option in exceptional cases only.

"Line Art and Text Resolution" option

In this box, you specify the final resolution of line art and text after transparency flattening. The setting range is between 72 and 2540 dpi.

"Gradient Resolution" option

In this box, you specify the final resolution of gradients after transparency flattening. The setting range is between 72 and 600 dpi.

"Convert Text to Outlines" option

With this option enabled, all text is converted to outline during transparency flattening. This option is disabled by default.

"Convert Strokes to Outlines" option

With this option enabled, all strokes are converted to outlines during transparency flattening. This option is disabled by default.