spectro/synthread
    Summary
    Simulate the measurement of a devices response using a synthetic
    device
    model. This is intended for testing of profile creation accuracy. A
    device link
    separation or color space conversion can be applied before the
    print/measure simulation.
    Usage
    synthread [-v] [separation.icm] inoutfile
       -v               
 
              Verbose mode
       -p                       
Use
        separation profile
       -l                       
Output
        Lab rather than XYZ
        
       -0
        pow                   
Apply
        power to input device chanel 0-9 (after sep.)
        
       -r
        level                 
Add
        average random deviation of <level>% to input device
        values
        (after sep.)
       -R
        level                 
Add
        average random deviation of <level>% to output PCS values
       -u
 
           
                        
Make
        random deviations have uniform distributions rather than normal
     -b
        L,a,b                 
Scale
        black point to target Lab value
       [separation.icm]         
Device
        link separation profile
       profile.[icm|mpp|ti3]     ICC, MPP
        or .ti3
        profile/file to use
       
      inoutfile          
 
              Base name for
        input[.ti1]/output[.ti3] file
    
      Examples
    
    synthread xxxx testvalues
    synthread -p xxx separation.icm testvalues
    Comments
    
    The -v flag does nothing at
    the moment.
    The -p flag enables a
    device
    to device value conversion before
    converting to expected PCS values.
    The -l flag causes the CIE
    output values to be L*a*b* rather than the
    default XYZ values.
    
    The -0, -1, -2 .. -9
    parameters are a way of simulating changes in the
    behaviour of the simulated printing system. The parameter supplied
    to
    the flag will be used to modify the device values (after any
    separation
    is applied) by raising them to the power of the parameter. This
    applies
    a transfer curve to the simulated device response.
    
    The -r parameter is a way
    of
    simulating instability in the behaviour of
    the simulated
    printing system. The parameter supplied to the flag will be used to
    scale a random offset added to the device values (after any
    separation
    is applied). The offset will be a normally distributed error with an
    average deviation of level%. A typically value supplied
    might be 1.0 to simulate 1% randomness.
    
    The -R parameter is a way
    of
    simulating instability in the behaviour of
    the simulated
    measuring system. The parameter supplied to the flag will be used to
    scale a random offset added to the PCS values. The offset will be a
    normally distributed error with an average deviation of level%. A
    typically value supplied
    might be 1.0 to simulate 1% randomness. 
    
    The -u flag changes the
    distribution of the random offsets applied using the -r or -R flags, from the default standard
    deviation, to a uniform deviation distribution. The level is still
    specified as an average deviation.
    
    The -b parameter is a way
    of
    simulating devices that have a different black point to the profile
    used. This only works if an ICC profile is used, and scales the
    black
    point to the parameter value. This will be done in XYZ space by
    default, and in L*a*b* space if the -l
    flag is used.
    
    synthread is useful in creating artificial test value for testing colprof, as well as providing one path for
    turning an MPP profile into an ICC profile. If a .ti3 file is
    specified instead of an ICC or
    MPP profile,
    then the closest matching measured points in the ..ti3 are substituted
    for the test values in the .ti1
    file on
    output. If the .ti1
    file is a monochrome test file with a White device value, then an
    RGB ICC profile, MPP or .ti3 may be used, and the White
    values will be translated to equal RGB values. If the .ti1
    file is a monochrome test file with a Black device value, then a
    CMYK ICC profile, MPP or .ti3 may be used, and the Black
    values will be translated to equal CMY = 0, K = grey values. 
    
    If a separation device profile is provided (e.g. from CMY ->
    CMYK,
    or perhaps CMYK->CMYK, to simulate a color correction step before
    "printing"), then this will be applied to the .ti1 device values,
    before converting the the device values into .ti3 PCS values.