Tiffany Overview

Tiffany was produced at Xerox PARC. It is supported by the Computer Science Laboratory at PARC.

Changes

March 30, 2004

Upgraded the documentation. Removed official support for PCL from the documentation. Added plex support under the -incMedia switch.

   ftp://ariel.parc.xerox.com/pub/tiffany/dp7.3/tiffany.tar.Z
   ftp://ariel.parc.xerox.com/pub/tiffany/dp8.0/tiffany.tar.Z
   ftp://ariel.parc.xerox.com/pub/tiffany/dp8.1/tiffany.tar.Z

   ftp://ftp.parc.xerox.com/pub/tiffany/dp7.3/tiffany.tar.Z
   ftp://ftp.parc.xerox.com/pub/tiffany/dp8.0/tiffany.tar.Z
   ftp://ftp.parc.xerox.com/pub/tiffany/dp8.1/tiffany.tar.Z

    cd /TD
    zcat tiffany.tar.Z | tar xvf -
    rm tiffany.tar.Z

    cd /TD; ./StartTiffany

Notes for render:

• gray 1 is binary, gray 8 is 8 bits/pixel grayscale
• HC is 1 bit/pixel with two separations (h+k)
• rgb 8 is 8 bits/pixel, 3 separations (r+g+b)
• cmyk 8 is 8 bits/pixel, 4 separations (c+m+y+k)
• cmyk 1 is 1 bit/pixel, 4 separations (c+m+y+k)

Notes for output:

• gray 1 is binary, gray 4 is 4 bits/pixel grayscale, gray 8 is 8 bits/pixel grayscale
• HC is 1 bit/pixel, two separations (2 files/page for TIFF)
• HCX is 8 bits/pixel, indexed color
• rgb 8 is 8 bits/pixel, 3 colors (interleaved samples)
• cmyk7 is seven binary separations: c+m+y+k+r+g+b

Other notes:

• binary output for TIFF is G4 encoded for compactness
• HC output is two binary separations; for TIFF this is two files/page
• for PS and TIFF output, all non-binary output is RLE (PackBits) encoded by default, but can be uncompressed if the -raw switch is used
• the anti-aliasing factor (-aa A) averages A*A pixels together, resulting in an output format that is reduced by a factor of A
• for -rgb and -cmyk the -aa switch can be omitted if A = 1

Simulating media

Tiffany supports simulated media for DocuPrint NPS compatibility for PDLs that support media selection. The DocuPrint NPS media model is similar to that of PostScript, with each media specification containing the size (width and height in mm), a media type, a media color, and an optional media weight (in gm/m**2). Here's a table of sample media specifications for common media:

Notes:

• size names are not yet supported, so use the explicit numeric sizes
• if no required media are specified the default is 216x279::white
• if no loaded media are specified the default is to derive the loaded media from the required media
• if no media height and width are specified the default is to use the size from the first of the required media (or 216x279 if there are no required media)

Example Tiffany conversions

We will be giving several examples of conversion from PostScript to TIFF files. In each case we will use the default page size (8.5x11 inches, 216x279 mm), the default resolution (300 spi), and a PostScript file named FFF. The output files will be in /tmp/dp.p000n.tif.

To produce monochrome TIFF files, with DocuPrint NPS orientation (the default), at 300 spi resolution rendering, and 300 spi resolution output, use:

    dp -tiff /tmp/dp FFF

To produce monochrome grayscale TIFF files, with screen orientation, at 300 spi resolution monochrome rendering, but 75 dpi resolution output, use:

    dp -sef -tiff /tmp/dp -gray FFF

To produce RGB color TIFF files, with screen orientation, at 300 spi resolution RGB rendering, but 75 spi resolution output, use:

    dp -sef -tiff /tmp/dp -rgb -aa 4 FFF

To convert a PostScript file FFF into a set of RGB color TIFF files, with orientation suitable for screen viewing, at 300 spi resolution highlight rendering, but 75 spi resolution output, assuming a highlight RGB color of <1 0 0>, use:

    dp -sef -tiff /tmp/dp -hc 1 0 0 -gray FFF

Tiffany switches

On a Tiffany command line the switches must preceed the source files. In most cases the action of a switch applies for all files on the command line after the switch. One important exception is that an output file name only applies to the results of the next input file.

• Output Formats

  -tiff P	requests TIFF output to file prefix P for compatibility, -tiff is the same as -g4prefix
  -ip F	requests Interpress output to file F for compatibility, -ip is the same as -out
  -ps F	requests PostScript output to file F for compatibility, -ps is the same as -outPS

• Rendering

  -aa K	requests crude anti-aliasing rendering takes place at normal resolution anti-aliasing pass averages KxK squares output resolution is reduced by factor of K
  -gray	requests gray rendering (4 bps or 8 bps, 1 separation) 4 bps is used with -aa 0 8 bps is used with -aa K, where K > 0
  -rgb	requests RGB rendering (8 bps, 3 separations)
  -cmyk	requests CMYK rendering (8 bps, 4 separations)
  -cmyk7	requests special CMYK rendering (1 bps, 7 separations) only implemented for IP output
  -hc R G B	requests HC rendering (1 bps, 2 separations) specifies the assumed highlight color as RGB color R, G and B are number from 0.0 through 1.0 -hc can be combined with -aa or -gray for full color output
  -hco R G B	requests output color for HC rendering specifies the output highlight color as RGB color R, G and B are number from 0.0 through 1.0 default uses the same color as -hc specifies
  -hco auto	special case for output color that attempts to use the loaded highlight color at the printer instead of a specific color for the highlight plane; uses red (1 0 0 ) if not printed on a printer supporting highlight color
  -hcr X	X specifies the highlight color rendering algorithm (one of automatic, pictorial, presentation, colorToHighlight, colorTables). The default is automatic, which selects between pictorial and presentation based on the element being rendered. The -hcr switch is only used for HC rendering.

• Resolution, Size and Shifting

  -res R	specifies the resolution in samples/inch (R may be a single number or a quoted "x,y" pair, as in "300,400"; non-integer resolutions are permitted)
  -w X U	X specifies the page width the optional U specifies the units (pt, in, ft, mm, cm, m), where the default is inches the default page width is 8.5 inches
  -h X U	X specifies the page height, the optional U specifies the units the default page height is 11 inches
  -xs X U	X specifies the X-axis shift, the optional U specifies the units
  -ys Y U	Y specifies the Y-axis shift, the optional U specifies the units
  -pvpt	applies a 72/75 output scaling to better match 72 spi displays (best results with IP output and rendering with -aa 4 or -gray)

• Orientation

  -sef	short edge feed (fast: right, slow: down) useful for screen viewing
  -lef	long edge feed (fast: up, slow: right) useful for DocuPrint NPS printers
  -sm X	explicit orientation of scan mode (slow,fast) X is one of UR, UL, DR, DL, LU, LD, RU, RD

• Pages

  -fp N	N specifies the first page to render (default is 1)
  -lp N	N specifies the last page to render (default is last page in document)

• Media

  -m M	adds a media spec M to the required media list
  -lm M	adds a media spec M to the loaded media list
  -incMedia	includes media selection and dynamic plex selection for PostScript output

• Plex simulation

  -simplex	simulates simplex printing (same as -1)
  -duplex	simulates duplex printing (same as -2)
  -tumble	simulates tumble duplex printing (same as -3)

• Special

  -format F	selects the document format explcitly F should be one of {IP, PS, ASCII}
  -title T	gives an explicit job title (useful for Decomp forms)
  -d	causes extra debugging information to be produced
  -prog	causes per page progress information to be produced
  -raw	forces uncompressed output files
  -pph P	forces halftones to be P pixels per halftone dot
  -tiffCount N	starts numbering of TIFF files at N for compatibility, -tiffCount is the same as -g4Count

Server use

It is sometimes desirable to run Tiffany as a server. To start Tiffany as a server use the following commands:

    cd /TD
    ./StartTiffanyServer &

As a server Tiffany accepts the same commands as it does interactively, but the commands are submitted by writing to the file /TD/Tiffany.cmd, for example:

    echo "SaveMaskG4 -title Tiger tiger.ps" >/TD/Tiffany.cmd

will cause the command (in quotes) to be executed by the Tiffany server. To examine the progress of the Tiffany server one can examine the tail of the log, as in

    tail -10 /TD/Tiffany.log

To stop the server, use the command

    echo Quit >/TD/Tiffany.cmd

To make some of these operations easier, consider using the Unix alias facility.

Multiple users writing to Tiffany.cmd are likely to lose commands, since the server will only see the most recent command line. However, once a command is accepted (1-2 seconds for an idle server) another command can be entered immediately.

Highlight color

Xerox produces some printers capable of Highlight Color, including the DocuPrint 4850, DocuPrint 4890 and DocuPrint 92c. Tiffany supports the same rendering as the NPS versions of the above printers.

In the Xerox terminology Highlight Color is black plus one color. One can think of this as a two separation color space with black as one plane and some other color as the other plane. In the current implementation the two colors are mutually exclusive, so a pixel can be black, white, or the highlight color, but not a combination of the black plus highlight.

Tiffany gives significant control over the choice of assumed colorant when producing the separations (the -hc switch), and also allows for separate determination of the color used for the highlight separation on output (the -hco switch).

Since any rendering of full color into black plus highlight separations must lose some colors, there are several highlight color rendering choices (the -hcr switch). To get closest color approximation for photographs, use -hcr pictorial. To preserve color distictions for line art and charts, use -hcr presentation. To have an automatic choice between pictorial and presentation on the same page, use -hcr automatic.

Targeting specific printers

In some cases you need to have Tiffany output be the same as the output for a specific DocuPrint NPS printer. There are two printer-specific parts: one for the Imager and one for PostScript.

For the Imager parameters, you need to append the commands from the file /usr/printing/cedar/IOTparams (on the target DocuPrint machine) to the file /TD/StartTiffany.cm. These commands control the Imager print parameters and font rendering parameters.

For the PostScript parameters, you may need to copy the file IOTSetup.ps from /usr/printing/cedar/ on the target DocuPrint to files of the same names on /TD/. A default IOTSetup.ps is provided that is usable for the 4135 family of printers (DP 96, DP 4635, DP 180).

Running VIPP (XGF)

VIPP is implemented as a set of PostScript files that provide useful functions. Tiffany does not by default include those files, but can use the same files that the DocuPrint NPS system uses. This section describes how to add VIPP support to Tiffany. It requires a version of Tiffany created on 31 July 1998 or later.

To install VIPP support for Tiffany you should know how to execute Unix commands on both the DocuPrint controller and the Tiffany workstation. You should also know how to transfer binary files from the DocuPrint controller to the Tiffany workstation.

To obtain the files, do the following Unix commands on a DocuPrint NPS system:

    cd /usr/printing/xgf/
    tar cf /var/tmp/xgf.tar

Then transfer /var/tmp/xgf.tar from the DocuPrint controller to the Tiffany workstation. If using FTP on the DocuPrint controller, remember to transfer using binary mode. Then do the following Unix commands on the Tiffany workstation (where /TD is the Tiffany directory).

    cd /TD; mkdir xgf; cd xgf
    tar xf /var/tmp/xgf.tar

Remember to remove /var/tmp/xgf.tar from both the DocuPrint controller and the Tiffany workstation.

Legacy Interpress

The Interpress files produced from the -out or -ip options are IMG compressed data with an Interpress wrapper suitable for sending directly to a DocuTech or DocuPrint printer. Therefore, Tiffany can be used on a fast Sun workstation to produce files for printing on a slower legacy DocuTech printer. The Interpress files produced contain no printing instructions.

Interpress containing Xerox Adaptive compressed data is not supported. This format requires hardware support for efficient decoding.