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function [finalSettings,badIndex,quantized,perError,settings] = SensorToSettingsAcc(cal,sensor)
% [finalSettings,badIndex,quantized,perError,settings] = SensorToSettingsAcc(cal,sensor)
%
% Convert from sensor color space coordinates to device
% setting coordinates. This routine makes use of the
% full basis function information to compensate for spectral
% shifts in the device primaries with input settings.
%
% This depends on the standard calibration globals.
%
% 11/12/93 dhb Wrote it.
% 3/30/94 dhb, jms Fixed logic bug in error computation.
% Return finalSettings as best during iteration
% 8/4/96 dhb Update for stuff bag routines.
% 8/21/97 dhb Update for structures.
% 3/10/98 dhb Change nBasesOut to nPrimaryBases.
% 4/5/02 dhb, ly New calling interface.
% 1/26/04 ly, dhb Get rid of unused variable called "error".
% 11/22/09 dhb Check basis dimension and do the simple fast thing if it is 1.
% This will speed things up when there is no point in trying the
% iterative algorithm.
% Algorithm parameters
nIterations = 10;
dampingFactor = 1.0;
% Determine sizes
[nLinear,nTargets] = size(sensor);
if (nTargets ~= 1)
error('Only handles one sensor target at a time');
end
settings = zeros(nLinear,nIterations);
quantized = zeros(nLinear,nIterations);
% Get basis information
nPrimaryBases = cal.nPrimaryBases;
if (isempty(nPrimaryBases))
error('No nPrimaryBases field present in calibration structure');
end
if (nPrimaryBases == 1)
[finalSettings,badIndex] = SensorToSettings(cal,sensor);
quantized = [];
perError = [];
settings = [];
else
% THINK ABOUT OUT OF GAMUT ISSUE. THIS COMMENTED
% OUT CODE WAS AN INITIAL STAB AT IT.
%primary = SensorToPrimary(cal,sensor);
%[nDevice,null] = size(primary);
%gamut = PrimaryToGamut(cal,primary);
%target = PrimaryToSensor(cal,gamut);
target = sensor;
aimfor = target;
for i = 1:nIterations
primary = SensorToPrimary(cal,aimfor);
[gamut,badIndex] = PrimaryToGamut(cal,primary);
settings(:,i) = GamutToSettings(cal,gamut);
[tmpQuantized,primaryE] = SettingsToSensorAcc(cal,settings(:,i));
quantized(:,i) = tmpQuantized;
calError(:,i) = quantized(:,i) - aimfor;
perError(:,i) = quantized(:,i) - target;
aimfor = target - dampingFactor*calError(:,i);
end
% Find minimum error that was encountered and return those settings
summaryError = diag(perError'*perError);
[null,minIndex] = min(summaryError);
finalSettings = settings(:,minIndex);
end
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