基于改进极限学习机的数码印花颜色空间转换方法

Color Space Conversion Method of Digital Printing Based on Improved Extreme Learning Machine

针对目前数码印花过程中颜色空间转换方法无法适应织物多样性引起的色差问题,提出一种改进的正则化极限学习机算法,实现L^(*)a^(*)b^(*)到CMYK颜色空间快速灵活转换。首先,选用PANTONE纺织TCX色卡作为实验的样本数据,随机选取800个色块,这些色块的L^(*)a^(*)b^(*)值作为输入,对应的C、M、Y、K值分别作为输出,训练网络,建立一个非线性映射,并根据岭回归模型的岭迹图观察法得出最优正则化惩罚系数,优化模型;随后,在TCX色卡剩余的色块中再随机选出100个色块作为模型的测试样本进行测试验证。实验结果表明,本文方法具有较高的转换精度和效率,最小转换色差为0.221,最大转换色差为6.965,平均转换色差为1.645,平均训练时间为1.489 s,能够满足数码印花色彩管理实际要求。

To solve the problem of the color difference caused by fabric diversity in the digital printing process,an improved regularization extreme learning machine algorithm is proposed to realize quick and flexible conversion from L^(*)a^(*)b^(*)to CMYK color space.First,select the PANTONE textile TCX color card as the sample data of the experiment,randomly select 800 color patches,the L^(*)a^(*)b^(*)values of these color patches are used as input,and the corresponding C,M,Y,and K values are used as output,respectively.The network is trained to establish a nonlinear mapping,and the optimal regularized penalty coefficient is obtained according to the ridge trace graph observation method of the ridge regression model to optimize the model.Then,100 color patches are randomly selected from the remaining color patches of the TCX color card as the test samples of the model for testing and verification.Experimental results show that the proposed method has high conversion accuracy and efficiency.The minimum conversion color difference is 0.221,the maximum conversion color difference is 6.965,the average conversion color difference is 1.645,and the average training time is 1.489 s,which can meet the actual requirements of digital printing color management.