Fine tuning preview generation

Xinet ships a preset, default preview-generation values. Many sites may find the Xinet-set values appropriate. You may, however, change these settings for any individual volume at any time. Any change, however, will only affect newly-generated previews, not those already in existence, unless you specifically update them (through the Update Previews tab).

Xinet allows you to fine tune the ways in which it automatically generates its For Placement Only and Web-ready images on a volume-by-volume basis:

1.	There are several ways to open the Preview Settings panel for a volume.

• Starting at the Volumes/Users, System Volumes, Summary tab, hover with your cursor over either a check mark in the FPO or Web columns. You should see the check mark highlight itself in blue.

Click on a highlighted check mark. It doesn’t matter which column. They both lead to the same page.

• Click on the Volumes/Users, Systems Volumes, Preview Settings tab, and select a volume in the Select a Volume pop-up list.

Figure 0-3 Preview generation options. The “Set as default options” button may alternatively be “Discard options (revert to defaults).”

2.	Select appropriate settings for the volume you are configuring. The table below provides information about what each parameter controls and how Xinet initially sets it.

For more information about preview options, also refer to the fpovolpts(4) man page, either online or in Volume 2, as not all of its options appear in the GUI.

Note: The options you set for Preview Generation may be set for the individual volume you are currently configuring and also, optionally, established as the default values that will be assigned to any volumes added in the future.

Parameter	fpovolopts(4) key1	Explanation
General image options
Ignore all Mask channels in Photoshop Native images	pm	Normally, Xinet will interpret some extra channels in PhotoShop Native files as masks. If this is not the behavior you want to see, turn on this option. When you do, the extra channels will be ignored and upon image substitution, images will appear as if the channel were not there.
Honor Spot and Mask channels in TIFFs (for Art Pro)	Q3	By default, Xinet ignores masks and spot colors on extra channels in TIFF files. If, however, you turn on this option, Xinet will not ignore them.
Honor Clipping paths in TIFF images	uc	If this option is on, when making previews for TIFF files, the server will “apply” clipping paths
Do not process Raw Camera (or Digital NEGative) files	nr	When used, the server will make neither FPO nor Web previews for raw camera files.
Grey Watermark (for Continuous Tone Images)	gz	Pathname to the default greyscale image that will be applied as a watermark to expired assets when Asset Timer Data Fields (see Default Data Fields:) are in use.
Render PDFs and EPSs with Overprint Simulation	op	Simulates on the monitor the effect of overprinting when rendering FPO previews for PDF and EPS files. Keep in mind that when rendered this way, there will be no alpha channel and consequently no GIF WEB preview. Also, keep in mind that when this feature has not been engaged, PDF and EPS files are rendered using their original color model (RGB, CMYK or Greyscale) to preserve a more accurate representation; turning on Overprint Simulation forces their rendering into CMYK. This feature, in particular, is useful when you don’t want to see die and varnish plates in Web previews.
Render all PDFs and EPSs completely Opaque	nm	By default, when rendering FPOs and previews of EPS and PDF files, only the “painted” parts of the image are opaque. This option causes the entire rectangle of the image to be opaque.
When performing ICC conversions, use Black Point Compensation	bp	This feature may help retain detail in dark (shadowed) areas in FPOs and previews if you also enable ICC color transformations on the volume. (See Color profiles for Xinet previews.) Success will vary according to a number of factors, so it’s best that you test in an environment where the images are likely to be previewed.
Default when resolution is unknown	dr	Some image formats do not supply a resolution for pictures (for example, SGI RGBs and some digital camera formats). When an image does not have a resolution set, Xinet uses the value assigned here for determining the dimensions of the FPOs. This value influences the scaling factor Mac users apply to print the image. Because different layout programs make different assumptions about images without resolution, users may see a jump in image dimensions when switching between FPOs and high-resolution versions. If your site uses InDesign set the value of this option to 72 DPI, the value InDesign assumes when it encounters an image without a known resolution. In mixed environments, the best solution might be to open files without a known resolution in an image editor and assign a resolution that way. Note: the integer value stored in fpovolopts(4) will be 10 times the DPI.
Minimum pixel dimension for previews (may increase FPO resolution)	mp	Default is 0, for example, the option will not be used. This option exists for instances when original vector artwork in EPS or PDF files is physically quite small (for example, a corporate logo), so that when previews are rendered, rounding errors may occur that effect the way the preview looks and make the FPO difficult to place accurately. Assigning a value here can help avoid very small previews.
B&W Watermark (for 1-bit/paletted images)	bz	Pathname to the default black-and-white image that will be applied as a watermark to expired 1-bit/paletted assets when Asset Timer Data Fields (see Default Data Fields:) are in use.
Options for FPO generation
Make EPS FPOs from all image formats	fm	By default, Xinet creates EPS FPOs for EPS files and TIFF FPOs for all other image formats. The Make EPS FPOs option makes it possible to generate EPS FPOs for all types of images. You might want to use this option when Mac users primarily use applications such as Adobe Illustrator, which doesn’t write OPI comments for TIFF FPOs, or if you have Windows clients within your workgroup. EPS FPOs also preserve the link to the high-resolution original image on the server when they are taken off site. The fm key takes one of three possible values: • eps = make EPS FPOs from all image types • noconv = make EPS FPOs from EPS or PDF files, make TIFF FPOs from all other files unless an image contains a clipping path, spot colors or mask • web = make Xinet-style Web previews
Don’t make EPS FPOs from 1-bit non-EPS images	bc	When making EPS FPOs from all image formats, this option excepts 1-bit images, making them TIFF instead.
Don’t make EPS from grayscale non-EPS images	gc	When making EPS FPOs from all image formats, this option makes an exception for grayscale images, creating TIFF FPOs instead.
Don’t make FPOs for “Vector” EPS files	nv	Vector EPS files are a special class of PostScript graphics that are already about as compact as they can get. Making a low-resolution FPO for them is not useful, and can lead to problems in some illustration programs that expect to read internal object structure on such files.
Don’t make FPOs for PDF files	np	Turning on this option will cause PDF files to be treated as non-image files. If you do not turn on this option, the first page of each PDF will be converted to an EPS FPO.
Do not make FPOs of TIFFs with spot or mask channels	nx	Allows mask channels in high-resolution images to be selected in some layout applications and extra (spot) channels to be tinted in Art Pro. Requires that mask channels be enabled.
Don’t make FPOs from native-JPEG files	pj	Leaves JPEG (JFIF) images as high-resolution images only
Do make FPOs from Raw Camera/GIF/ ArtPro CTs	nn	When on, Xinet will make previews for raw camera, GIF, and ArtPro CTs.
Don’t copy-protect FPOs (only if making all EPS)	nc	By default, FPOs are copy protected. Turning on this option makes it possible to export EPS FPOs without using the Xinet FPO Exporter to explicitly break links to high-resolution corollaries. This can be done safely for EPS FPOs because they contain path and file ID information; TIFF FPOs do not, however, so be aware that breaking their links will cause confusion. Use this in conjunction with the fm key.
Make PICTs even for TIFF FPOs	tp	If used, Xinet will generate PICT previews, even for TIFF FPOs
Maximum size of the FPO (in Kilobytes)	sz	You can constrain the FPO resolution so that each FPO has a maximum size in kilobytes. If you use this in combination with resolution limits, Xinet will generate an FPO which is a union of the constraints. You may set a value by typing in the text box.
Limit the preview image to maximum resolution	rs	You can constrain the FPO resolution so that each FPO is created at a specified number of dots per inch (DPI) or per centimeter (DPCM). Most Macintosh monitors display information at 72 DPI, so 72 is a reasonable setting. If you set the resolution in combination with data size limits, Xinet will generate FPOs which are a union of the constraints. You may set a value by typing in the text box. Note: The integer value stored in fpovolopts(4) is 10 times the DPI.
Grey Watermark (for Continuous Tone images)	gw	You may want to watermark FPOs. The watermarks will not appear in any high-resolution images that get substituted at print time. (It’s best to use a greyscale image for continuous tone image watermarks.) Refer to Adding watermarks for details.
B&W Watermark (for 1-bit/palleted images)	bw	You may want to watermark FPOs. The watermarks will not appear in any high-resolution images that get substituted at print time. (It’s best to use a black and white image for 1-bit/palleted image watermarks.) Refer to Adding watermarks for details.
Options specific to EPS-format FPOs
Omit images (include a gray Bounding Box only)	bb	You might want to turn on this option when you know Mac users primarily use applications, such as versions of Adobe Illustrator, which only recognize EPS files and you are sure they won’t need printable previews for the low resolution images (for example., when they print proofs it won’t matter that they see gray boxes where the images should be). Printable EPS previews take extra space on the server and have an impact on performance. This option is mutually exclusive with other FPO resolution constraints because Bounding Boxes do not carry a concept of resolution.
Use ASCII for EPS images (default is BINARY)	as	You need to use this option if you will be printing FPOs to imaging devices which cannot handle binary PostScript files.
Include PC-style TIFF preview	ms	Turning on this option will cause Xinet to insert PC-style TIFF previews into EPS FPOs. See the Xinet PC Connectivity Guide for more information about OPI replacement on Windows workstations.
Do not include default OPI comments	na	When on, Xinet will not insert the Standard OPI “ALDImage” comments into FPOs.
JPEG encoding	jp j	By default Xinet will not JPEG-encode EPS FPOs unless the high-res files are already JPEG-compressed. In some cases, however, you will see that the FPOs are not smaller than the originals. To overcome this, Xinet includes the option to JPEG-compress all EPS FPOs, at three quality levels, Low Quality, Medium Quality, and High Quality. You will get smaller FPOs this way (the lower the quality, the smaller the FPO). Using one of these settings will not effect the quality of the high-resolution image at print time; it will only change the FPO. Using JPEG-compressed EPS FPOs will affect the quality of images if you are proofing material using the FPO images rather than the high-resolution images. The lower the quality you’ve selected, the less the printed FPO will look like the original. Another caution is that if you want to print the FPO, you must use, at least, a PostScript Level II RIP which understands JPEG encoding.
Do NOT JPEG-encode image data even if Hi-Res is encoded	nj	When enabled, Xinet will no longer retain any existing JPEG compression from high-resolution images when building previews.
Include masks as Level-3 PostScript	3m	Include masks in EPFS FPOs via a PostScript Level-3 Masked Image operator. These FPOs will produce PostScript errors when printed to a PostScript Level 1 or 2 device. This option key overrides em.
Omit masks channel from FPO	em	Causes EPSF FPOs to omit any mask from the high-resolution original. By default, masks are included via PostScript Level 2 patterns and will not render correctly (not, however, because of a PostScript error) on Level 1 RIPs.
PICT previews • Do not make • 8-bit • Full color • Full color (OS9)	pi	Xinet automatically generates QuickTime (PNOT) previews for every FPO. Some programs use QuickTime previews in dialog boxes. You cannot suppress their generation. Xinet, however, also generates PICT previews. You may turn off this option or choose between palleted (8-bit) previews, Full color (the default setting), or Full color (OS9) previews. Please check your Macintosh application documentation to see whether PICT previews are used by particular applications your users run. PICT previews are used, for example, by the Aldus Fetch image catalogue program. They are also used to provide screen previews for EPS FPO images. (Without them, Mac users will see gray bounding boxes.)
		The Xinet 8-bit setting builds palleted previews (including masks) which look acceptable on most kinds of monitors. Full color previews provide more detail, although, of course they take more memory. These previews look better on full color monitors. Full color previews differ from Full color (OS9) previews when the high-resolution image has a mask or clipping path: they present more intricate masks, which have the potential to crash OS9 clients. That’s because the more “holey” PICT masks are, the more likely it is that Os9 systems will crash when trying to display them. Note that because Full color (OS9) previews still take more memory than 8-bit ones.
Always generate PICTs regardless of timestamp	wp	The Xinet server will ignore PNOT timestamps when this option is used. The server will then replace all PICT previews, if PICT making has been turned on.
Options for Large Web Previews:
Don’t make Web previews from Vector EPS files	nv	Only useful if you find it necessary to save processing power.
Don’t make Web previews for PDF files	np	Turning on this option will cause PDF files to be treated as non-image files. If you do not turn on this option, the first page of each PDF will be converted to a JPEG or GIF, depending on transparency. Multipage PDF previews are handled independently.
Include ICC profiles in JPEG previews	sp	This will ensure that JPEG WEB previews contain either an ICC profile from the high-res image (if that high-res is RGB and contains a profile already) or the ICC profile selected to represent RGB previews on the server (if set). If you use this feature, that profile will be embedded in the JPEG preview and then allow properly-equipped applications and browsers to display the preview based on ICC color transformations. (See Color profiles for Xinet previews for information about color fidelity in other sorts of previews.)
Always make JPEGs (GIFs are usually made of masked images)	ng	Because it is not possible to preserve masks and clipping paths in JPEG previews, Xinet, by default, will make GIF previews when they are present. GIF previews, however, will not be as sharp as JPEG previews. This option allows you to force JPEG previews of all images.
Limit the preview image to maximum resolution	rs	You may also limit image resolution by DPI or DPCM. By default, Xinet sets this value to 72 DPI. You may, however, type in other values. The values stored in fpovolopts(4) are 10 times the DPI.
Limit the image to maximum pixel dimension	px	If you want to limit the pixel dimensions of WEB previews, check the box for this option and include a value in the type-in box. In some instances the value you set here may override the resolution for Web previews. That’s because, even at the selected resolution, some images can be too large to fit in a Web browser window. This option limits an image to a specified number of pixels.
Grey Watermark (for Continuous Tone images)	gw	You may want to watermark Web previews. The watermarks will not appear in any high-resolution images that are downloaded. (It’s best to use a greyscale image for continuous tone image watermarks.) Refer to Adding watermarks for details.
B&W Watermark (for 1-bit/palleted images)	bw	You may want to watermark Web previews. The watermarks will not appear in any high-resolution images that are downloaded. (It’s best to use a black-and-white image for 1-bit/palleted image watermarks.) Refer to Adding watermarks for details

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1

The strings shown in this column are keys used by fpovolopts(5)

3.	The selections you make will have no effect until you click on one of the buttons at the bottom of the window. Choices there include:

• Set options for this volume
Saves the currently displayed values for the volume.

• Set as default options
Saves the currently displayed values for the system, so that each new volume thereafter will, by default, initially have these values.

This option toggles between Set as default options and Discard options (revert to defaults) depending on whether the stored options for the volume match the stored default options.

• Cancel
Dismisses the currently displayed values in favor of the values last set for the volume.

After changing options, the Update Previews page, described in the following topic Updating previews, will open automatically. This allows you to ensure that all of your images will have previews generated in the same way. If you do update previews, older previews may work in a different fashion than new ones. The Update Previews page will open with appropriate previews already selected for you.