基于ICC标准的扫描仪色彩特性化研究
摘要
扫描仪是印刷系统中最主要的一种图像获取设备,由于受到设备颜色特性、观察条件、色域范围等诸多因素的影响,一幅彩色图像原稿在扫描过程中,阶调层次和色彩信息常常会丢失,不能够忠实再现原稿,直接影响着后续工作的正常进行。因此,对扫描仪进行以ICC为标准的色彩特性化研究是十分必要的。
选取AGFA DUOSCAN T2500为主要研究对象,分别对标准IT8.7/2色标和自设色靶进行扫描实验和数据处理,采用多元回归方法和BP神经网络改进方法分别建立了扫描仪的ICC特性文件,并分析了目标色空间、多元回归项及项数、不同的变换方式、建模样本数、隐层神经元数目、训练时间、网络层数等参数对模型精度的影响。自行开发了创建扫描仪ICC特性文件的软件,并进行了软件的色彩管理效果的评价。
研究结果表明:将色度信号线性化引入到多元回归算法中,能够提高模型的精度,20项的M5模型的精度最高;增加常数项可以提高以CIE LAB为输出空间的模型精度,增加交叉项可以提高以CIE XYZ为输出空间的模型精度;隐层神经元数目在25-35之间均可以达到较好的精度,而采用三层3-30-3的一步正割的BP训练方法可以较好得改进BP神经网络训练精度。合二为一的基于混合模型的扫描仪特性文件综合了基于N维查表模型的输入设备特性文件和基于三维矩阵模型的输入设备特性文件两者的优点,增强了数据转换的确定性,提高了特性文件的精度。以CIE LAB为PCS空间的基于混合模型的特性文件色彩管理效果最好,优于ProfileMaker的精度。
Scanner is one of the most important devices for obtaining images in printing system. Gradation of tone and color information of a color picture original often disappear in the scanning process and original manuscript can't be re-created trustily in virtue of devices' colorimetric characteristic, observation conditions, colorimetric ration and other influencing factors. As a result, the follow-up process can't be preceded regularly. Therefore, it is very necessary to study scanner's colorimetric characterization in accordance with standard ICC.
AGFA DUOScan T2500 is the principal object of study. Standard IT8.7/2 and designed color target were scanned and handled dates individually. ICC profiles of scanner were established individually in the method of polynomial regression algorithm and BP neural network theory. Parameters influencing model precision were analyzed. These parameters include target color space, polynomial regression items, items number, different conversion types, modeling specimen quantity, number of concealed gradation, training time, number of network gradation and so on. A soft-ware establishing a scanner ICC profiles was exploited voluntarily and the color management outcome of the exploited software was estimated.
It was indicated: Model precision was enhanced by injecting chromatic signal linear into polynomial regression algorithm and the precision of 20th model M5 is the best. Model precision of output space CIE LAB can be enhanced by adding constant terms and model precision of output space CIE XYZ can be enhanced by adding intersects. The number of concealed gradation neuron between 25 to30 can obtain better precision and training precision of BP neural network can be enhanced more validly by using three gradations 3-30-3 one step secant BP training way. The scanner profiles based on mixed models integrate N-component LUT-based input profiles advantage and Three-component matrix-based input profiles advantage. The decision of date transformation and the precision of profiles were enhanced. The profiles based on mixed models and output space CIE LAB PCS whose color management outcome is the best and whose precision is better than Profile Maker.
选取AGFA DUOSCAN T2500为主要研究对象,分别对标准IT8.7/2色标和自设色靶进行扫描实验和数据处理,采用多元回归方法和BP神经网络改进方法分别建立了扫描仪的ICC特性文件,并分析了目标色空间、多元回归项及项数、不同的变换方式、建模样本数、隐层神经元数目、训练时间、网络层数等参数对模型精度的影响。自行开发了创建扫描仪ICC特性文件的软件,并进行了软件的色彩管理效果的评价。
研究结果表明:将色度信号线性化引入到多元回归算法中,能够提高模型的精度,20项的M5模型的精度最高;增加常数项可以提高以CIE LAB为输出空间的模型精度,增加交叉项可以提高以CIE XYZ为输出空间的模型精度;隐层神经元数目在25-35之间均可以达到较好的精度,而采用三层3-30-3的一步正割的BP训练方法可以较好得改进BP神经网络训练精度。合二为一的基于混合模型的扫描仪特性文件综合了基于N维查表模型的输入设备特性文件和基于三维矩阵模型的输入设备特性文件两者的优点,增强了数据转换的确定性,提高了特性文件的精度。以CIE LAB为PCS空间的基于混合模型的特性文件色彩管理效果最好,优于ProfileMaker的精度。
Scanner is one of the most important devices for obtaining images in printing system. Gradation of tone and color information of a color picture original often disappear in the scanning process and original manuscript can't be re-created trustily in virtue of devices' colorimetric characteristic, observation conditions, colorimetric ration and other influencing factors. As a result, the follow-up process can't be preceded regularly. Therefore, it is very necessary to study scanner's colorimetric characterization in accordance with standard ICC.
AGFA DUOScan T2500 is the principal object of study. Standard IT8.7/2 and designed color target were scanned and handled dates individually. ICC profiles of scanner were established individually in the method of polynomial regression algorithm and BP neural network theory. Parameters influencing model precision were analyzed. These parameters include target color space, polynomial regression items, items number, different conversion types, modeling specimen quantity, number of concealed gradation, training time, number of network gradation and so on. A soft-ware establishing a scanner ICC profiles was exploited voluntarily and the color management outcome of the exploited software was estimated.
It was indicated: Model precision was enhanced by injecting chromatic signal linear into polynomial regression algorithm and the precision of 20th model M5 is the best. Model precision of output space CIE LAB can be enhanced by adding constant terms and model precision of output space CIE XYZ can be enhanced by adding intersects. The number of concealed gradation neuron between 25 to30 can obtain better precision and training precision of BP neural network can be enhanced more validly by using three gradations 3-30-3 one step secant BP training way. The scanner profiles based on mixed models integrate N-component LUT-based input profiles advantage and Three-component matrix-based input profiles advantage. The decision of date transformation and the precision of profiles were enhanced. The profiles based on mixed models and output space CIE LAB PCS whose color management outcome is the best and whose precision is better than Profile Maker.
引文
[1]田全惠,刘君.印刷色彩管理[M].北京:印刷工业出版社,2003.67-74
[2]张桂兰.扫描仪--电脑影像输入设备[M].北京:印刷工业出版社,1998.2-40
[3]李纲,马健.扫描仪技术原理.宁夏工学院学报[J],1996,8(2):67-69
[4]郭标.平板式-滚筒式扫描仪的优缺点.印刷技术[J],1998,32:10-11
[5]张桂兰.浅谈扫描仪的色彩校正.印刷技术[J],1998,45:10-12
[6]谢永忠.扫描仪的扫描与案例及相关知识.印刷杂志[J],2002,191:22-23
[7]Dan Gookin著,范彦译.数字扫描与照相[M].北京:北京大学出版社,2002.32-53
[8]International Color Consortium.Specification ICC.1:2004-10[EB/OL].http://www.color.org,2004-10/2006-06-20
[9]张晓燕.基于ICC标准的色彩管理系统研究--输入设备特性研究及特性描述文件的建立:[硕士论文][D].西安:西安理工大学,2000
[10]景翠宁.基于ICC标准的输出设备的色彩管理研究:[硕士论文][D].西安:西安理工大学,2002
[11]熊凯,胡涛.计算机输入输出设备色彩管理系统的研究:[硕士论文][D].西安:西安理工大学,2005
[12]张二虎,卞正中,胡涛.基于ICC标准的彩色扫描仪色彩检测及标定[J].仪器仪表学报.2004,25(5):611-614
[13]王歆平.基于ICC标准的色彩管理系统研究--显示设备特征研究及特征描述文件的建立:[硕士学位论文][D].西安:西安理工大学.2000
[14]粱炯.色彩管理工艺手册[M].北京:印刷工业出版社,2005.76-98
[15]戴淑进.印刷过程进行色彩管理的必要性.印刷杂志[J].2004,223:32-34
[16]金洪勇.印刷过程中金基于ICC的色彩管理实施方法.印刷杂志[J].2007.6:39-41
[17]杨建枫.基于ICC标准下的色彩管理的局限性.印刷杂志[J].2004,223:51-52
[18]Po-Chieh Hung.Colorimetric Calibration for Scanners and Media[J],SPIE,Vol.1448
[19]Michael J.Vrhel,color device calibration:a mathematical formamulation,IEEE,8(12),1796-1805
[20]景翠宁.ICC标准文件格式探析.印刷杂志[J].2003,1:48-52
[21]张帆.基于ICC设备特征文件的色彩管理,印刷杂志[J].2005,229:28-41
[22]Joann M.tayor,Integrated color management:the key to color control in electronic imaging and graphic systems,SPIE,1460,2-19
[23]Henry R.Kang,color scanner calibration,Journal of imaging science and technology,1992,36(2),162-170
[24]王勇,徐海松.给予多项式回归模型的扫描仪色度特征化.光学学报[J].2007,Vol.27(6):1135-1138
[25]马艳满,刘昕,刘浩学.数码相机的色彩管理研究:[硕士论文][D].西安:西安理工大学,2007
[26]Xu Yanfang,Liu Wenyao,Zuo Kunlong et al.Characterization of color scanners[J].Optics and Precision Engineering,2003,12(1):15-20
[27]何颂华,王利婕,陈琪莎.基于数码相机特性文件的色彩校正和色彩管理研究.包装工程[J],2005,Vol.26(5):78-81
[28]史瑞芝.用查表插值法实现CIE Lab与CMYK颜色空间的转换.测绘学院学报[J],19(3),224-226,2002
[29]眭海刚,张静.GeoStar中扫描仪色彩特性化模型的建立与评价.测绘信息与工程[J],1999,3(2):48-50,
[30]黎新伍,郝重阳,樊养余,马苗,张先勇.一个基于Neugebauer方程的输入图像色彩误差校正模型.仪器仪表学报[J],2004,Vol.25(4):498-500
[31]Cao Congiun,Zhou Mingquan,Xu Jinlin.Research on equation from L~*a~*b~* to CMY.仪器仪表学报[J],2004,Vol.25(4):129-132
[32]Zhou Shuang-quan,Zhao Da-zun.Study on tri-stimulus transformation.Journal of Beijing Institute of Technology[J],2000,Vol.9(1):37-44
[33]余鸿飞,石俊生,杨卫平.扫描仪的颜色表征、校正和ICC RProfile建立方法.云南示范大学虚报[J],2002,Vol.22(6),
[34]付建华.彩色打印机色彩空间转换方法研究:[硕士学位论文][D].中国科学院研究生院,2004.2:35-38
[35]Hui-liang Shen,John H.Xin.Colorimetric and spectral characterization of a color scanner using local statistics[J],J.Imaging Science and Technology,2004,48(4):342-346
[36]Zhou Shuang-quan,Zhao Da-zun.Neural network method for characterizing video camero.Pro.SPIE:62-68,1998
[37]廖宁放,高稚允.BP神经网络用于函数逼近的最佳隐层结构.北京理工大学学报[J],1998,Vol.18(4):476-480
[38]胡涛,刘睿,张志刚.基于BP网络的扫描仪色彩空间转换模型的研究.印刷杂志[J],2002:43-44
[39]赵磊,成刚虎.印前系统色彩传递特性的研究:[硕士论文][D].西安:西安理工大学[J],2005
[40]郭茂祖,王亚东,苏晓红,王兴起.基于BP网络的色彩匹配方法研究.计算机学报[J],2000,23(8),28-46
[41]H.R.Kang,Color control of printer by neural network[J],J.Electronic imaging[J],1998,7
[42]Zhou Shuang-quan,Zhao Da-zun.Neural Network Method for Colorimetry Calibration of Viedo Cameras.Journal of Beijing Institute of Technology[J],2000,Vol.9(1):31-36
[43]加卢什金著,阎平凡译.神经元网络理论[M].北京:清华大学出版社.2002
[44]张代远.神经网络新理论与方法[M].北京:清华大学出版社.2006
[45]飞思魁及产品研发中心著.神经网络理论与MATLAB 7实现[M].北京:电子工业出版社,2005
[46]Liu Shide,Chong Wenzhou.Designing Standard Original for Scanner and Its Application,China Academic Journal Electronic Publishing House[J],2002,25(4):191-194.
[47]肖洋.如何建立ICC标准特征描述文件.广东印刷[J],2004,25-26
[48]盖丽英,成刚虎.谈平台式扫描仪ICC Profile文件的创建.今日印刷[J],2007,32-35
[49]金洪勇.印刷过程中金基于ICC的色彩管理实施方法.印刷杂志[J],2007,51-53
[50]Huan Hui,Li Wei,Zhao Da-zun.New color-difference formula based on CIECAM97s.Journal of Beijing Institute of Technology,2001,Vol.10(2):149-152
[2]张桂兰.扫描仪--电脑影像输入设备[M].北京:印刷工业出版社,1998.2-40
[3]李纲,马健.扫描仪技术原理.宁夏工学院学报[J],1996,8(2):67-69
[4]郭标.平板式-滚筒式扫描仪的优缺点.印刷技术[J],1998,32:10-11
[5]张桂兰.浅谈扫描仪的色彩校正.印刷技术[J],1998,45:10-12
[6]谢永忠.扫描仪的扫描与案例及相关知识.印刷杂志[J],2002,191:22-23
[7]Dan Gookin著,范彦译.数字扫描与照相[M].北京:北京大学出版社,2002.32-53
[8]International Color Consortium.Specification ICC.1:2004-10[EB/OL].http://www.color.org,2004-10/2006-06-20
[9]张晓燕.基于ICC标准的色彩管理系统研究--输入设备特性研究及特性描述文件的建立:[硕士论文][D].西安:西安理工大学,2000
[10]景翠宁.基于ICC标准的输出设备的色彩管理研究:[硕士论文][D].西安:西安理工大学,2002
[11]熊凯,胡涛.计算机输入输出设备色彩管理系统的研究:[硕士论文][D].西安:西安理工大学,2005
[12]张二虎,卞正中,胡涛.基于ICC标准的彩色扫描仪色彩检测及标定[J].仪器仪表学报.2004,25(5):611-614
[13]王歆平.基于ICC标准的色彩管理系统研究--显示设备特征研究及特征描述文件的建立:[硕士学位论文][D].西安:西安理工大学.2000
[14]粱炯.色彩管理工艺手册[M].北京:印刷工业出版社,2005.76-98
[15]戴淑进.印刷过程进行色彩管理的必要性.印刷杂志[J].2004,223:32-34
[16]金洪勇.印刷过程中金基于ICC的色彩管理实施方法.印刷杂志[J].2007.6:39-41
[17]杨建枫.基于ICC标准下的色彩管理的局限性.印刷杂志[J].2004,223:51-52
[18]Po-Chieh Hung.Colorimetric Calibration for Scanners and Media[J],SPIE,Vol.1448
[19]Michael J.Vrhel,color device calibration:a mathematical formamulation,IEEE,8(12),1796-1805
[20]景翠宁.ICC标准文件格式探析.印刷杂志[J].2003,1:48-52
[21]张帆.基于ICC设备特征文件的色彩管理,印刷杂志[J].2005,229:28-41
[22]Joann M.tayor,Integrated color management:the key to color control in electronic imaging and graphic systems,SPIE,1460,2-19
[23]Henry R.Kang,color scanner calibration,Journal of imaging science and technology,1992,36(2),162-170
[24]王勇,徐海松.给予多项式回归模型的扫描仪色度特征化.光学学报[J].2007,Vol.27(6):1135-1138
[25]马艳满,刘昕,刘浩学.数码相机的色彩管理研究:[硕士论文][D].西安:西安理工大学,2007
[26]Xu Yanfang,Liu Wenyao,Zuo Kunlong et al.Characterization of color scanners[J].Optics and Precision Engineering,2003,12(1):15-20
[27]何颂华,王利婕,陈琪莎.基于数码相机特性文件的色彩校正和色彩管理研究.包装工程[J],2005,Vol.26(5):78-81
[28]史瑞芝.用查表插值法实现CIE Lab与CMYK颜色空间的转换.测绘学院学报[J],19(3),224-226,2002
[29]眭海刚,张静.GeoStar中扫描仪色彩特性化模型的建立与评价.测绘信息与工程[J],1999,3(2):48-50,
[30]黎新伍,郝重阳,樊养余,马苗,张先勇.一个基于Neugebauer方程的输入图像色彩误差校正模型.仪器仪表学报[J],2004,Vol.25(4):498-500
[31]Cao Congiun,Zhou Mingquan,Xu Jinlin.Research on equation from L~*a~*b~* to CMY.仪器仪表学报[J],2004,Vol.25(4):129-132
[32]Zhou Shuang-quan,Zhao Da-zun.Study on tri-stimulus transformation.Journal of Beijing Institute of Technology[J],2000,Vol.9(1):37-44
[33]余鸿飞,石俊生,杨卫平.扫描仪的颜色表征、校正和ICC RProfile建立方法.云南示范大学虚报[J],2002,Vol.22(6),
[34]付建华.彩色打印机色彩空间转换方法研究:[硕士学位论文][D].中国科学院研究生院,2004.2:35-38
[35]Hui-liang Shen,John H.Xin.Colorimetric and spectral characterization of a color scanner using local statistics[J],J.Imaging Science and Technology,2004,48(4):342-346
[36]Zhou Shuang-quan,Zhao Da-zun.Neural network method for characterizing video camero.Pro.SPIE:62-68,1998
[37]廖宁放,高稚允.BP神经网络用于函数逼近的最佳隐层结构.北京理工大学学报[J],1998,Vol.18(4):476-480
[38]胡涛,刘睿,张志刚.基于BP网络的扫描仪色彩空间转换模型的研究.印刷杂志[J],2002:43-44
[39]赵磊,成刚虎.印前系统色彩传递特性的研究:[硕士论文][D].西安:西安理工大学[J],2005
[40]郭茂祖,王亚东,苏晓红,王兴起.基于BP网络的色彩匹配方法研究.计算机学报[J],2000,23(8),28-46
[41]H.R.Kang,Color control of printer by neural network[J],J.Electronic imaging[J],1998,7
[42]Zhou Shuang-quan,Zhao Da-zun.Neural Network Method for Colorimetry Calibration of Viedo Cameras.Journal of Beijing Institute of Technology[J],2000,Vol.9(1):31-36
[43]加卢什金著,阎平凡译.神经元网络理论[M].北京:清华大学出版社.2002
[44]张代远.神经网络新理论与方法[M].北京:清华大学出版社.2006
[45]飞思魁及产品研发中心著.神经网络理论与MATLAB 7实现[M].北京:电子工业出版社,2005
[46]Liu Shide,Chong Wenzhou.Designing Standard Original for Scanner and Its Application,China Academic Journal Electronic Publishing House[J],2002,25(4):191-194.
[47]肖洋.如何建立ICC标准特征描述文件.广东印刷[J],2004,25-26
[48]盖丽英,成刚虎.谈平台式扫描仪ICC Profile文件的创建.今日印刷[J],2007,32-35
[49]金洪勇.印刷过程中金基于ICC的色彩管理实施方法.印刷杂志[J],2007,51-53
[50]Huan Hui,Li Wei,Zhao Da-zun.New color-difference formula based on CIECAM97s.Journal of Beijing Institute of Technology,2001,Vol.10(2):149-152