Step no. 1: First output of 6+5 standard colours or 32 ISO/IEC-test colours with different transfer functions here called reference output
Step no. 2: Second output of 6+5 standard colours or 32 ISO/IEC-test colours with different transfer functions changed by a square root function in File (F)
Step no. 3: Third output of 6+5 standard colours or 32 ISO/IEC-test colours with different transfer functions changed by a square root function in Distiller Startup (S) directory
Step no. 4: Fourth output of 6+5 standard colours or 32 ISO/IEC-test colours with different transfer functions changed by a square root function in PostScript device (D)

Test intention for Colour Management:
A standard image file including cmyn* color data or 8bit image data in relative coordinates cmyn* and olv* (rgb*) is changed by a transfer function to produce the same output by different Colour Management methods using the Colour Management data in the PS-file (F), a Distiller Startup (S) directory, or in the PS-device (D) memory, e. g. a PS-printer.

Method:
A Colour Management file CMYN*TRANS.PS is used to store the following data:
The standard PS-operators setgray, setrgbcolor, setcmykcolor and setransfer are modified and include then a square root transfer function for olv* and a square function for cmyn* changing all colours to lighter colours for the whole output page.

In a first step four global (g) PS-operators are defined to be identical to the standard PS-operators
/sggray {setgray} bind def
/sgrgbcolor {setrgbcolor} bind def
/sgcmykcolor {setcmykcolor} bind def
/sgtransfer {settransfer} bind def
/sgcolortransfer {setcolortransfer} bind def

Then the former standard PS-operators are redefined by the four global (g) PS-operators which are modified by the PS-square root function {sqrt = 0.5 exp} here in this example.

%p=positive or n=negative change with lightness for olv* (rgb*) and cmyn*
/prozp {0.5 exp} bind def /transp {prozp} bind def
/prozn {2.0 exp} bind def /transn {prozn} bind def

/setgray {transp sggray} def

/setcmykcolor {/ncolor exch transn def /ycolor exch transn def
/mcolor exch transn def /ccolor exch transn def ccolor mcolor ycolor ncolor sgcmykcolor} def

/setrgbcolor {/bcolor exch transp def /gcolor exch transp def
/rcolor exch transp def rcolor gcolor bcolor sgrgbcolor} def

/settransfer {/ntransfer exch def {ntransfer transp} sgtransfer} def
/setcolortransfer {/ntransfer exch def /ytransfer exch def /mtransfer exch def /ctransfer exch def {ctransfer transp} {mtransfer transp}{ytransfer transp} {ntransfer transp} sgcolortransfer} def

The effect is very important for Colour Management: All colour data of the 8bit image and colour patches on the whole page are modified by the PS-square root function and become lighter.

Files for Colour Management: There are three methods (no. 2 to 4) to make the modifications. The most effective way (no. 4) is to store the file CMYN*TRANS.PS in a PS-device, e. g. a PS-printer. Then the PS-interpreter in the PS-printer will change all colours according to the redefined PS-functions: setgray, setcmykcolor, setrgbcolor, settransfer, and setcolortransfer.

If the transfer functions in the Colour Management file CMYN*TRANS.PS for any device are based on CIELAB Colour Measurement of the first output on this devices then any standard PS-image file will produce the same visual output on any device. This is not realized in the examples here which only give the theoretical basis for this intention.

Thefore the following examples will show that it seems possible that any 8bit image file (based on an standard P.PS-file) will produce the same visual output on any device (not only on PS-devices).

This is an important solution for Colour Management as many PS-image files (A.PS- and P.PS-files) are based on only a few PS-operators which are modified according to the Colour Management file CMYN*TRANS.PS for the device output.

Colour Management by digital test files including cmyn* data in the setcmykcolor PS-operator	Remarks for use and reproduction	PostScript format File type A.TXT or A.PS	PostScript and Portable Document Format (Version 3.0) File type P.PS or P.PDF
Step no. 1: First output of 6+5 standard colours with no setcmykcolor transfer	First output used as reference (no.1)	L8620ENA(.TXT / .PS) 355 kByte	L8620ENP(.PS / .PDF ) 355 / 92 kByte
Step no. 2: Second output of 6+5 standard colours with setcmykcolor transfer defined by a square root function in File (F)	Second output making all colours lighter by an additional square function in file (F) compared to the reference (no. 1)	L8620EFA(.TXT / .PS) 355 kByte	L8620EFP(.PS / .PDF ) 355 / 92 kByte CMYN*TRANS(.TXT / .PS) 2 kByte (Allready included in file (F) for distilling the file L8620EFA.PS)
Step no. 3: Third output of 6+5 standard colours with setcmykcolor transfer defined by a square root function in Distiller Startup (S) directory	Third output making all colours lighter by an additional square function in Startup (S) compared to the reference (no. 1)	L8620ESA(.TXT / .PS) 355 kByte	L8620ESP(.PS / .PDF ) 355 / 92 kByte CMYN*TRANS(.TXT / .PS) 2 kByte (To copy to distiller Startup (S) directory, before distilling L8620ESP.PS)
Step no. 4: Fourth output of 6+5 standard colours with setcmykcolor transfer defined by a square root function in PostScript device (D)	Fourth output making all colours ligther by an additional square function in Device (D) compared to the reference (no. 1)	L8620EDA(.TXT / .PS) 355 kByte CMYN*TRANS(.TXT / .PS) 2 kByte (To store in PS-device before downloading L8620EDA.PS to this PS-Device)	L8620EDP(.PS / .PDF ) 355 / 92 kByte (The file CMYN*TRANS.PS is included here to show the Device output of L8630EDP.PS)

Table 1: The files in Table 1 use cmyn* data for the PS-operator setcmykcolor.
The page with 16 figures shows the different colour codes (SGcode, MGcode and WGcode) and the tranformations between 8bit, 7bit, and 6bit data. The following abreviations are used: s=standard, z=centralized to mean gray, i=integer, h=hexadecimal data. The data range is given in the figures. For non image data there is no loss in accuracy using 6bit, 7bit or 8bit data.
All Figures of the page are changed by the three methods of colour management (no. 2 to .4) compared to the reference (no. 1). More information about the content of all the figures of this page is given by the publication:

http://o2.ps.bam.de/CISO08.PDF

Colour Management by digital test files including cmyn* data and olv* image data using settransfer	Remarks for use and reproduction	PostScript format File type A.TXT or A.PS	PostScript and Portable Document Format (Version 3.0) File type P.PS or P.PDF
Step no. 1: First output of 6+5 standard colours with no setcmykcolor transfer	First output used as reference (no.1)	L8630ENA(.TXT / .PS) 575 kByte	L8630ENP(.PS / .PDF ) 575 / 267 kByte
Step no. 2: Second output of 6+5 standard colours with setcmykcolor transfer defined by a square root function in File (F)	Second output making all colours lighter by an additional square function in file (F) compared to the reference (no. 1)	L8630EFA(.TXT / .PS) 575 kByte	L8630EFP(.PS / .PDF ) 575 / 267 kByte CMYN*TRANS(.TXT / .PS) 2 kByte (Allready included in file (F) for distilling the file L8630EFA.PS)
Step no. 3: Third output of 6+5 standard colours with setcmykcolor transfer defined by a square root function in Distiller Startup (S) directory	Third output making all colours lighter by an additional square function in Startup (S) compared to the reference (no. 1)	L8630ESA(.TXT / .PS) 575 kByte	L8630ESP(.PS / .PDF ) 575 / 267 kByte CMYN*TRANS(.TXT / .PS) 2 kByte (To copy to distiller Startup (S) directory, before distilling L8630ESP.PS
Step no. 4: Fourth output of 6+5 standard colours with setcmykcolor transfer defined by a square root function in PostScript device (D)	Fourth output making all colours ligther by an additional square function in Device (D) compared to the reference (no. 1)	L8630EDA(.TXT / .PS) 575 kByte CMYN*TRANS(.TXT / .PS) 2 kByte (To store in PS-device before downloading L8630EDA.PS to this PS-Device)	L8630EDP(.PS / .PDF ) 575 / 267 kByte (The file CMYN*TRANS.PS is included here to show the Device output of L8630EDP.PS)

Table 2: The files in Table 2 use cmyn* data for the PS-operator setcmykcolor and olv* data in the last two images (Fig. E8631-7 and -8). The PostScript settransfer function is used to change the images.
The page with 16 figures shows different triangle coordinates and colour codes (SGcode, sgcode and mgcode) and the tranformations between 8bit and 7bit data. The following abreviations are used: s=standard, z=centralized to mean gray, i=integer, h=hexadecimal data. The data range is given in the figures. For non image data there is no loss in accuracy using 6bit or 7bit data. The last two figures of the page use 8bit olv* image data.
All Figures of the page are changed by the three methods of colour management (no. 2 to .4) compared to the reference (no. 1). More information about the content of all the figures of this page is given by the publication:

http://o2.ps.bam.de/CIE2B1.PDF

Colour Management by digital test files including 8bit image data and use of {o*=l*=v*} settransfer	Remarks for use and reproduction	PostScript format File type A.TXT or A.PS	PostScript and Portable Document Format (Version 3.0) File type P.PS or P.PDF
Step no. 1: First output of 32 ISO/IEC-test colours with no transfer	First output used as reference (no.1)	L8640ENA(.TXT / .PS) 120 kByte	L8640ENP(.PS / .PDF ) 120 / 25 kByte
Step no. 2: Second output of 32 ISO/IEC-test colours with different transfer functions changed by a square root function in File (F)	Second output including 16 gray steps with linear, square and square root output, now all colours lighter by an additional square function in file (F) compared to the reference (no. 1)	L8640EFA(.TXT / .PS) 120 kByte	L8640EFP(.PS / .PDF ) 120 / 25 kByte CMYN*TRANS(.TXT / .PS) 2 kByte (Allready included in file (F) for distilling the file L8640EFA.PS)
Step no. 3: Third output of 32 ISO/IEC-test colours with different transfer functions changed by a square root function in Distiller Startup (S) directory	Third output including 16 gray steps with linear, square and square root output, now all colours lighter by an additional square function in Startup (S) compared to the reference (no. 1)	L8640ESA(.TXT / .PS) 120 kByte	L8640ESP(.PS / .PDF ) 120 / 25 kByte CMYN*TRANS(.TXT / .PS) 2 kByte (To copy to distiller Startup (S) directory, before distilling L8640ESP.PS
Step no. 4: Fourth output of 32 ISO/IEC-test colours with different transfer functions changed by a square root function in PostScript device (D)	Fourth output including 16 gray steps with linear, square and square root output, now all colours ligther by an additional square function in Device (D) compared to the reference (no. 1)	L8640EDA(.TXT / .PS) 120 kByte CMYN*TRANS(.TXT / .PS) 2 kByte (To store in PS-device before downloading L8640EDA.PS to this PS-Device)	L8640EDP(.PS / .PDF ) 120 / 25 kByte (The file CMYN*TRANS.PS is included here to show the Device output of L8630EDP.PS)

Table 3: The files in Table 3 use olv* data in the images. The PostScript settransfer function is used to change the images.
All Figures of the page are changed by the three methods of colour management (no. 2 to .4) compared to the reference (no. 1)

Colour Management by digital test files including 8bit image data and use of olvn* setcolortransfer	Remarks for use and reproduction	PostScript format File type A.TXT or A.PS	PostScript and Portable Document Format (Version 3.0) File type P.PS or P.PDF
Step no. 1: First output of 32 ISO/IEC-test colours with no transfer	First output used as reference (no. 1)	L8650ENA(.TXT / .PS) 12 kByte	L8650ENP(.PS / .PDF ) 120 / 25 kByte
Step no. 2: Second output of 32 ISO/IEC-test colours with different transfer functions changed by a square root function in File (F)	Second output including 16 gray steps with linear, square and square root output, now all colours lighter by an additional square function in file (F) compared to the reference (no. 1)	L8650EFA(.TXT / .PS) 12 kByte	L8650EFP(.PS / .PDF ) 120 / 25 kByte CMYN*TRANS(.TXT / .PS) 12 kByte (Allready included in file (F) for distilling the file L8650EFA.PS)
Step no. 3: Third output of 32 ISO/IEC-test colours with different transfer functions changed by a square root function in Distiller Startup (S) directory	Third output including 16 gray steps with linear, square and square root output, now all colours lighter by an additional square function in Startup (S) compared to the reference (no. 1)	L8650ESA(.TXT / .PS) 12 kByte	L8650ESP(.PS / .PDF ) 120 / 25 kByte CMYN*TRANS(.TXT / .PS) 12 kByte (To copy to distiller Startup (S) directory, before distilling L8650ESP.PS
Step no. 4: Fourth output of 32 ISO/IEC-test colours with different transfer functions changed by a square root function in PostScript device (D)	Fourth output including 16 gray steps with linear, square and square root output, now all colours ligther by an additional square function in Device (D) compared to the reference (no. 1)	L8650EDA(.TXT / .PS) 15 kByte CMYN*TRANS(.TXT / .PS) 12 kByte (To store in PS-device before downloading L8650EDA.PS to this PS-Device)	L8650EDP(.PS / .PDF ) 120 / 25 kByte (The file CMYN*TRANS.PS is included here to show the Device output of L8630EDP.PS)

Table 4: The files in Table 4 use olvn* data (n=00) in the images. The PostScript setcolortransfer function is used to change the images.
All Figures of the page are changed by the three methods of colour management (no. 2 to .4) compared to the reference (no. 1)

Colour Management by digital test files including 8bit image data and use of cmyn* setcolortransfer	Remarks for use and reproduction	PostScript format File type A.TXT or A.PS	PostScript and Portable Document Format (Version 3.0) File type P.PS or P.PDF
Step no. 1: First output of 32 ISO/IEC-test colours with no transfer	First output used as reference (no. 1)	L8660ENA(.TXT / .PS) 120 kByte	L8660ENP(.PS / .PDF ) 120 / 25 kByte
Step no. 2: Second output of 32 ISO/IEC-test colours with different transfer functions changed by a square root function in File (F)	Second output including 16 gray steps with linear, square and square root output, now all colours lighter by an additional square function in file (F) compared to the reference (no. 1)	L8660EFA(.TXT / .PS) 120 kByte	L8660EFP(.PS / .PDF ) 120 / 25 kByte CMYN*TRANS(.TXT / .PS) 2 kByte (Allready included in file (F) for distilling the file L8660EFA.PS)
Step no. 3: Third output of 32 ISO/IEC-test colours with different transfer functions changed by a square root function in Distiller Startup (S) directory	Third output including 16 gray steps with linear, square and square root output, now all colours lighter by an additional square function in Startup (S) compared to the reference (no. 1)	L8660ESA(.TXT / .PS) 120 kByte	L8660ESP(.PS / .PDF ) 120 / 25 kByte CMYN*TRANS(.TXT / .PS) 2 kByte (To copy to distiller Startup (S) directory, before distilling L8660ESP.PS
Step no. 4: Fourth output of 32 ISO/IEC-test colours with different transfer functions changed by a square root function in PostScript device (D)	Fourth output including 16 gray steps with linear, square and square root output, now all colours ligther by an additional square function in Device (D) compared to the reference (no. 1)	L8660EDA(.TXT / .PS) 120 kByte CMYN*TRANS(.TXT / .PS) 2 kByte (To store in PS-device before downloading L8660EDA.PS to this PS-Device)	L8660EDP(.PS / .PDF ) 120 / 25 kByte (The file CMYN*TRANS.PS is included here to show the Device output of L8630EDP.PS)

Table 5: The files in Table 5 calculate inverse olvn* data by {1 exch sub} and use therefore cmyn* data (n=00) in the images. The PostScript setcolortransfer function is used to change the images.
All Figures of the page are changed by the three methods of colour management (no. 2 to .4) compared to the reference (no. 1)

Remarks to the files:
There are three identical PostScript-files with the file extensions "A.TXT", "A.PS" and "P.PS" and one PDF-file "P.PDF".

The file with the extention "A.TXT" is used to show directly the PostScript-program code in the browser window.

The file with the extention "A.PS" is used for download to the local drive and is used for output on a PostScript printer or a Display PostScript System.

Very important remarks: The file with the name CMYN*TRANS.PS includes the Colour Management data. This file is only a part of a PostScript program. There are three possibilities to locate (store) this program:

1. The file CMYN*TRANS.PS is included in the file L8640EFA.PS to produce a download to a PS-device, e. g. a printer. Or the file L8640EFP.PS and the standard Distiller are used to distill the P.PS-file.

2. The file CMYN*TRANS.PS is added to a Startup (S) directory (there is one file Example.ps allready). It is recommended here to use the standard Distiller in a special directory (_S=Startup) to distill the P.PS-file L8640ESP.PS (For more information look at the following).

3. The file CMYN*TRANS.PS is added to the PS-definitions in a PostScript device (e. g. a printer or DPS-System). The PS file L8640EDA.PS is downloaded to the PS-device (D). The information in this file is used for every output (in normal case for every output until restart of the PS-device).

Five remarks to the important possibility no. 2 (Colour Management data in Startup directory):
Remark 1: You may add the file CMYN*TRANS.PS to the existing file Example.ps in the Startup (S) directory of the Acrobat 3.0 (or 4.0) directory but this is not recommended here as every distiller job will then use this information!

Remark 2: It is recommended to duplicate the Adobe Acrobat 3.0 (or 4.0) directory (about 50 Mbyte or install only Acrobat Distiller in this new directory (10 Mbyte)) and rename this directory to Acrobat 3.0_S. This directory then also includes the directory Startup (S) with the only existing file Example.ps. Add the file CMYN*TRANS.PS. If You start the Distiller stored in the Acrobat_S directory then this information will be used in all Distiller jobs.

Remark 3: You can use the standard directory Acrobat 3.0 (without _S) including the standard Distiller for all jobs to distill as usual.

Remark 4: You must quit the Distiller program if You change the file CMYN*TRANS.PS in the Startup (S) directory and if You like to use the changed data within the next Distiller job.

Remark 5: You may include the file Example.ps which will avoid to change cmyn*-data to olv* (rgb*)-image data. There is also the possibility to use the preference menue of Adobe Acrobat Distiller for this task. See Example.ps

With PS-files one can reach the best reproduction in colour and resolution. One can use by the operating system Windows "copy" and by the operating system Macintosh "download" to print the PS-file by a PostScript printer.The PS-file can be viewed directly on a colour monitor by a Display Postscript system (e. g. Nextstep, Openstep on Windows, Yap on Macintosh OS X server).

The file with the extention "P.PS" includes additionally the alphanumeric sequence "P.PS->P.PDF". The P.PS-file may be downloaded to the local drive and transfered to a P.PDF-file by the local software Adobe Acrobat Distiller or equivalent.

The file with the extention "P.PDF" is viewed in the browser window if AdobePDFviewer is installed as browser plugIn. This P.PDF-file may be downloaded to the local drive and viewed with Adobe Acrobat Reader.

The following is very important only if the method is used to optimize the output (by CIELAB colour measurement of the first output which defines the transfer function depending on measurement data).

If the P.PDF-file test is used, then the local P.PS file must be transfered to a P.PDF file by the local computer operating system with the same version of Adobe Acrobat Distiller or an equivalent software.

Remark: The transformation from a P.PS-file to a P.PDF-file may depend on the Distiller version or the version of the equivalent software. Therefore the P.PDF-file from the internet should not be used for the test.

The test result is independend of the Distiller version or the version of the equivalent software. One can use the P.PDF-file to view the digital file on any monitor and to print on any colour or black and white printer (not only PS-printers) by Adobe Acrobat Reader (or Exchange) Version 2.1, 3.0 or 4.0.

This information with german text: DG06

Test procedure for output:
Basic material:
There are 16 files, 4 as Text (A.TXT), 4 as PostScript (A.PS), 4 as PostScript (P.PS), and 4 as Portable Document (P.PDF).
Test method:
There is a reference output no. 1 and three lighter outputs no. 2 to no. 4 which are approximately identical. The smal differences are only based on the reproduction properties of the colour output and the different interpretation of software and devices of A.PS and A:PDF files. Some combinations (square output including square root transfer) must produce the reference output of the first top left picture.

For PostScript(PS) printers and Display-PostScript(DPS) systems one should use the A.PS files. The transfer of the P.PS files to the P.PDF files allows the output on any printer.

1. PDF-file output on any printer
If the test uses not a PS printer and not a DPS system then Adobe Acrobat Distiller or an equivalent software is necessary to transfer the EPS file into the PDF file. The PDF file is normaly viewed on the monitor and printed by the printer driver.

2. PS-file output on a PS-printers
If the test uses a PostScript (PS) printer then the software Adobe Acrobat Distiller or an equivalent is not necessary. The A.PS-files is used by the PS-interpreter in the printer to make the output on the PS-printer.

3. PS-file output on a DPS-system (e. g. Mac OS X Server, Application Yap)
If the test uses a Display PostScript (DPS) system then the software Adobe Acrobat Distiller or an equivalent is not necessary. The A.PS-files is used by the PS-interpreter of the DPS-system to view the file on the monitor and to make the output by the printer driver of the DPS system on any printer (PS- and other printers).

4. PDF-file output on a PDF-printer
If the test uses a Portable Document (PDF) printer then the software Adobe Acrobat Distiller or an equivalent is necessary to transfer the P.PS-file into a P.PDF-file. The P.PDF-file is used by the PDF-interpreter in the PDF-printer to make the output on the PDF-printer.

The following feature is valid only if the Colour Management data in the file CMYN*TRANS.PS are based on the device, e. g. CIELAB colour measurement of the first output.
1. There is the same test result independent of the three above test methods (no. 2 to no. 4) used.
2. The test result is independent of the Adobe Acrobat Distller Software version and the PostScript version
Remark 1: Examples and methods how to store the file CMYN*TRANS.PS in the PS-devices are not realized here.
Remark 2: Examples which include CIELAB colour measurement data in the file CMYN*TRANS.PS are not realized here.

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