2 An introduction to HELIOS ImageServer
ImageServer facilitates the handling of large image files in a typical prepress environment, and can be used for server-based repurposing of image files, including color management, color space transformation, compression, resolution, and image file format conversion between all supported image formats.
Note: HELIOS ImageServer runs on top of the foundation provided by HELIOS Base. Please read the HELIOS Base manual for installation instructions and other important details.
2.1 New ImageServer features
For new features in the ImageServer software see the HELIOS web site:
For HELIOS Base, the foundation used by all HELIOS UB products, see the Base product web page:
2.2 ImageServer functionality
HELIOS ImageServer incorporates much more than just OPI image replacement. ImageServer is an integrated solution that makes the entire image management and print workflow more versatile and efficient. Here are some general advantages of OPI, along with additional features of ImageServer:
- Speed improvement and output optimization
- Remote workflow support
- Color management
- Composite PDF generation overcomes QuarkXPress limitations
- Composite DeviceN printing support overcomes QuarkXPress limitations
- Script Server workflow automation
- Image conversion
- Re-purpose the same print job
- Application compatibility
- Error checking
- QuarkXPress and InDesign document previews
These capabilities are detailed in the following sections, and in other areas of this manual.
2.2.2 OPI functionality (image replacement)
At first, you scan your original image with an appropriate (comparatively high) resolution. Then, you retouch this high-resolution image using an image processing application (such as Photoshop) and save the result. As soon as the new high-resolution original image file is saved in a HELIOS volume, the OPI software automatically generates a low-resolution duplicate (called a
layout file) that needs much less disk space. OPI-compatible layout applications such as QuarkXPress or InDesign, which are running on network clients, can work with these small low-resolution proxy files which leads to a reduction of processing time. All modifications like positioning, scaling, or rotating are marked by OPI comments which are inserted in the PostScript when you launch the print command. During printing, the modifications are applied to the high-resolution original images that now replace the low-resolution substitutes.
With this concept, large image files are completely kept away from the layout computers in a network. Thus, printing from a client is much faster and the network traffic is reduced.
Fig.
1 shows a prepress environment and illustrates how you can benefit from HELIOS ImageServer.
This same concept is also used to enable remote workflow support via the Internet.
Fig. 1: The handling of image files on ImageServer
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The OPI standard and the syntax and structure of OPI comments were created by the Aldus Corporation that now belongs to Adobe Systems, Inc.
2.2.3 Server-based image conversion
ImageServer supports a wide range of image formats and color spaces including clipping paths and spot colors. It can convert images to any supported file format, resolution, compression and color space to be used for printing, web, archive, or any other purpose. HELIOS PDF HandShake adds PDF file format support. See also:
This image conversion capability is used extensively by ImageServer "behind the scenes". It can also be configured to provide automatic or hot folder based image conversion per user specifications.
2.2.4 Server-based color management
ImageServer supports ICC profiles and includes full ColorSync support, which has been co-developed with Heidelberger. ICC profiles will be applied for layout generation, image conversion, printing and proofing. ICC profiles can be tagged to individual images, for a specific folder as well as for volume and server defaults. See
5 "Using ImageServer" for more information.
ImageServer includes a Script Server service which implements a hot folder mechanism. You simply drop files into the hot folder. The idea of a hot folder is that, as soon as files are dropped into this folder, a process is automatically started which converts the files according to a given script. See
7 "Script Server" for more information.
2.2.6 HELIOS OPI TuneUp XT
ImageServer supports background colorization of Black & White and Grayscale TIFF images. Foreground colorized images have already been supported in the previous versions. ImageServer supports both foreground and background colorized images. To enable these features in QuarkXPress, ImageServer includes the extension "HELIOS OPI TuneUp XT" for QuarkXPress (Windows and Macintosh versions) which can be used with any QuarkXPress version, including Asian versions. The extension includes additional ADSC comments in the print job, which allow colorizing images during OPI replacement. See
5.8 "Using QuarkXPress with ImageServer" for instructions on how to use the "HELIOS OPI TuneUp XT".
2.2.7 InDesign and QuarkXPress document previews
The HELIOS Preview plug-in allows creating preview files of Adobe InDesign 2.x or InDesign CS documents (see
5.9.1 "The HELIOS Preview plug-in"). HELIOS Preview XT creates previews of QuarkXPress documents utilizing these previews (see
5.8.3 "The HELIOS Preview XT"). Local and remote web based users can preview InDesign or QuarkXPress documents from creation to final output, without needing access to the application, documents, fonts, or images. Previews can be viewed in any web browser using the included web server cgi-script ("docpreview.cgi") to publish directories with document previews.
In addition, HELIOS WebShare provides full remote file viewing, management, and transfer, for easy and secure remote collaboration, using any web browser.
These multi-page preview files facilitate finding documents, content verification, and local and remote collaboration. Preference settings specify the preview resolution. ImageServer "Action Scripts" allow fully automated processing for archiving, printing, converting to any major image file format, or to a customized workflow. See
7 "Script Server".
There are still some situations that might cause problems when working with ImageServer. In most cases, this is due to application specific incompatibilities. The following list of known restrictions is not "everlasting". You should always compare it to the latest README files issued by HELIOS, in order to find out whether a problem has already been fixed.
ImageServer does not support layer masks saved in Photoshop native format. When using layer masks in Photoshop and saving the images as Photoshop native, blank layout images will be generated. Please apply any layer mask to its layer and remove it before saving the image.
ImageServer does not fully support PICT images based on object descriptions other than PixMaps. Such images may be created by applications like Illustrator or FreeHand and may cause incomplete previews.
ImageServer will not work as expected if mounting NFS volumes using the UNIX auto-mount facility. Please hard mount NFS volumes by using the mount program.
We found that QuarkXPress matches spot color names found in placed EPSF files to its own ones by comparing the names of the imported colors with the built-in color tables. The program sometimes matches names which are only partially identical and then continues using its own names when editing colors and printing. This may result in missing spot color plates because the plate printed by QuarkXPress does not match the spot color name in the image. To avoid such problems, you should rename the spot colors in your images.
An image generated by Adobe Photoshop includes a channel named "PANTONE Orange 021 CVC". QuarkXPress matches it to "PANTONE Orange 021 CV" in its own table and uses this name further on. While printing, a plate named "PANTONE Orange 021 CV" will be printed but no OPI image replacement can be done because of the different name stored in the image.
For PC-EPSF format DCS images in QuarkXPress, printing
Separations will cause problems when you include images in the print job.
Include Images for
TIFF and
EPS must NOT be selected. Otherwise, QuarkXPress will generate bad PostScript.
