ConvertToRastersDoc.tioga
Maureen Stone, October 27, 1988 5:01:02 pm PDT
CONVERTTORASTERS
CEDAR 7.0 — FOR INTERNAL XEROX USE ONLY
ConvertToRasters
Maureen Stone
© Copyright 1988 Xerox Corporation. All rights reserved.
Abstract: ConvertToRasters is a general purpose package for generating grayscale rasters using ImagerSmoothContext. It is used for generating tapes for the Optronics and Crosfield formats, and for testing color correction procedures.
Created by: Maureen Stone
Maintained by: Maureen Stone <Stone.pa>
Keywords: Imaging, rasters
XEROX  Xerox Corporation
   Palo Alto Research Center
   3333 Coyote Hill Road
   Palo Alto, California 94304

For Internal Xerox Use Only
Basic Routines
Read the interface ConvertToRasters
Testing color operations on TimsToy
Install the software
Install ConvertToRasters
First, make a color correction procedure. The data files provided should produce a gray wedge that is gray and linear in L*. For measuring, we want to use correctionType = grayBalanceOnly. To print example pretty pictures, use correctionType = full. Mik has other data files in /ivy/lamming/top/CalTool.df.
← &cc ← PrintColorTransformations.ProcFromCCSpec[ccSpec: "TimsToy.CCSpec", correctionType: grayBalanceOnly]
Then, make a rasterSpec. fSize and sSize are the size of the raster. When imaging an interpress master measured in inches, the raster size should be the ppi below times the size in inches. IE, the example is an image 7 inches wide and 3.25 inches tall at 72 ppi.
← &ppi ← 75 -- Use 300 for maximum precision (but it will be very slow)
← &rasterSpec ← ConvertToRastersImpl.CreateRasterSpec[type: cmyk, fSize: Real.Round[7*&ppi], sSize: Real.Round[0.5+3.25*&ppi], surfaceUnitsPerPixel: 4, colorCorrection: &cc, maxPixel: 255, scanMode: Imager.defaultScanMode]
Then generate a CMYK, color corrected Interpress master. For TimsToy, you should use the offset by the amount shown (tx: 0.2, ty:1.4) to put an image with the lower left corner at the origin on the printing part of the page. x,y,w and h provide a clipping window for large masters (w=h=0 means no clipper). The example shows the part of the master defined by the window [: 0.4, y: 2.23, w: 7, h: 3.4] imaged on the printed page such that the lower left corner of the window is at [tx: 0.2, ty: 1.4]
ConvertToRastersImpl.IPToRasterIP[ipIn: "testwedges.ip", ipOut: "///7.0/test/testwedges.ip", ppi: &ppi, page: 1, rasterSpec: &rasterSpec, x: 0.4, y: 2.23, w: 7, h: 3.4, tx: 0.2, ty: 1.4]
Send the master to TimsToy
SendIPMaster ///7.0/test/testwedges.ip -h TimsToy