摘要:
What is disclosed is a system and method for merit-based gamut mapping. In one embodiment, color points are clustered in regions of interest within a color space. Each cluster is associated with a gamut mapping function and a merit function. Mapping parameters of each gamut mapping function are iteratively varied to optimize the values based on the merit function value. An optimized gamut mapping function results. Optimized gamut mapping functions of adjacent clusters are blended together by blending the value of the gamut mapping function for a point of a cluster with a value produced by the gamut mapping function of an adjacent cluster for that color point. The composite gamut mapping function contains the optimized gamut mapping functions of all clusters is then output for use in mapping points within those clusters to points within the target gamut. The composite gamut mapping function exploits local advantages of each cluster.
摘要:
Systems and methods are disclosed of a smooth gray component replacement strategy which utilizes the full gamut of a printer device. A CMY to CMYK gray component replacement transform is disclosed which inherently exploits the full gamut of the printer, by transforming points in CMY cube to L*a*b* color space, scaling the obtained values so they fill the maximum gamut obtainable with the printer device and calculating the CMYK values needed to obtain the scaled L*a*b* values. The CMY to CMYK transform is then smoothed with an averaging filter that does not change CMYK values at the corners. The entire color gamut is adequately sampled and small changes in CMY do not produce large jumps in L*a*b*.
摘要翻译:公开了利用打印机设备的全色域的平滑灰色组件替换策略的系统和方法。 公开了CMY到CMYK灰色组件替换变换,其通过将CMY多维数据集中的点转换为L * a * b *颜色空间来固有地利用打印机的全色域,缩放所获得的值,使得它们填充由打印机可获得的最大色域 并计算获得缩放的L * a * b *值所需的CMYK值。 然后使用不改变拐角处的CMYK值的平均滤波器平滑CMY到CMYK变换。 整个色域被充分采样,CMY的小变化不会在L * a * b *中产生大的跳跃。
摘要:
A transformation function defines a relationship between a first color space and a second color space. The transformation function is edited by producing first and second outputs of an image in the first and second color spaces, respectively. The outputs are related in accordance with the transformation function. A portion of the first output, which corresponds to a portion of the second output including a color to be modified, is selected via a graphical user interface. A desired amount to modify the color is specified. A correction function is determined in accordance with the desired amount. The transformation table is edited in accordance with the monotonic correction function.
摘要:
A thermal transfer printing device, including an ink donor supporting an ink meltable upon the application of a selected temperature, a printing head supporting a resistive heating element for generating the selected temperature at the ink donor, and means for bringing a final image support surface into contacting relationship with the ink donor in timed relationship to the application of the selected temperature to the ink donor including an electrically conductive heat sink layer, a heat resistant organic material having a very low thermal conductivity deposited on the heat sink layer and an array of resistors, supported on the heat resistant organic material, each resistor selectively controllable to apply a melting temperature to the meltable ink. The heat resistant organic material having a very low thermal conductivity is desirably a polyimide.
摘要:
Described herein is a method to encode infrared (IR) security watermarks using a named color dictionary within a PDL in a device independent manner. A set of colors is chosen that lies within the common gamut of printing devices and then defined in a device-independent color space. For each color and output device, a metameric pair of device colorant values corresponding to minimum and maximum black (K) is obtained using inversion techniques. These extremes are selected in order to obtain the maximum perceivable IR signal. The metameric pair sets are processed to extract a smaller subset that satisfies certain criteria, including bounds on the K difference, total ink area coverage, and deviation from the neutral axis. The final data is then stored in resource files that link fixed device-independent IR color names to pairs of variable device-dependent colorant values.
摘要:
What is disclosed is a novel system and method for determining color profiles based upon optimizing output image spatial noise. For each of a number of selected output colors, spatial noise values for a set of device-dependent color specifications that produce the selected output color are iteratively determined. The set of device-dependent color specifications is generated by varying a subset of colorants in the device-dependent color specifications while changing the remaining colorants to maintain the selected output color. The iterative process improves the spatial noise value, as determined by a spatial noise model, of the device-dependent color specifications that correspond to the selected output color. When an optimum spatial noise value is found, the device-dependent color specification having that spatial noise value is selected as the mapping for the selected device-independent color specification. Various embodiments are disclosed.
摘要:
What is disclosed is a novel system and method for generating a color lookup table (LUT) that minimizes interpolation errors over the entire color space, including the off-grid colors. The present method for LUT optimization considers off-grid point errors in assigning entries to the LUT. As described herein further, grid point values are computed that provide a least mean square error solution for the entire printer gamut volume. The present method dramatically reduces errors near the gamut boundary and can be used for populating nodes of any LUT that will be linearly interpolated, not only a table mapping from L*a*b* to CMYK.
摘要翻译:所公开的是用于生成使包括离网颜色在内的整个颜色空间内的插值误差最小化的颜色查找表(LUT)的新型系统和方法。 用于LUT优化的本方法在将条目分配给LUT时考虑离网点错误。 如本文进一步描述的,计算网格点值,其为整个打印机色域体积提供最小均方误差解。 本方法大大减少了色域边界附近的误差,可用于填充将被线性插值的任何LUT的节点,而不仅仅是从L * a * b *到CMYK的表映射。
摘要:
What is disclosed is a novel system and method for adjusting the gray balance of a multifunction color marking device in order to change the device's neutral behavior to a desired level of acceptability. The gray balance aim curve is specified by: L*, L*(aim), a*(aim) and b*(aim), where L*(aim)=f1(L*), a*(aim)=f2(L*), and b*(aim)=f3(L*). After receiving the user-modified gray balance aim curve, the target color device constructs a 3-D N×N×N L*a*b* to L*a*b* pre-LUT to reflect the neutral aim change by transforming a neutral axis input of L*, a*=0 and b*=0 to L*(aim), a*(aim) and b*(aim). Colors further away from the neutral axis are shifted by a lesser amount. The pre-LUT is then concatenated with the current color LUT to produce an updated color LUT which is applied to the device to achieve the desired neutral behavior. The gray balance aim curve can also be based upon a pre-determined user preference.
摘要翻译:所公开的是用于调整多功能彩色标记装置的灰度平衡以便将装置的中性行为改变到期望的可接受程度的新型系统和方法。 灰度平衡目标曲线由下式指定:L *,L *(瞄准),a *(瞄准)和b *(瞄准),其中L *(瞄准)= f1(L *),a *(瞄准)= f2 (L *)和b *(aim)= f3(L *)。 在接收到用户修改的灰平衡目标曲线之后,目标彩色装置通过将中性轴变换为中性目标变化来构造一个3-DN×N×NL * a * b *到L * a * b * L *,a * = 0和b * = 0到L *(瞄准),a *(瞄准)和b *(瞄准)的输入。 远离中性轴的颜色偏移较少。 然后,将前LUT与当前颜色LUT进行连接以产生更新的颜色LUT,其被施加到设备以实现期望的中性行为。 灰平衡目标曲线也可以基于预先确定的用户偏好。
摘要:
What is disclosed is an image path that advantageously uses halftone classification to select appropriate mappings in gray-scale management and color management operations. The tags generated in the scanner help identify different classes of halftones. One is selected from several pixel-value mappings to provide proper compensation. That is, the one-dimensional and multi-dimensional pixel-value mappings within the color management module are selected based on halftone classification tags from the scanner. The tagging is either one bit that indicates “Low Frequency Halftone” and “Not LFHT”, or, more preferably, the tag is multi-bit indicating a frequency bin that contains the frequency of the input halftone. Additionally, the multi-bit tag can indicate particular halftone screen types, such as dot screens, line screens, stochastic screens or error diffusion. The pixel value mappings are typically implemented as Look-Up Tables (LUTs), and the LUTs of the present invention are optimized for the various halftone classes. Generation of the LUTs, or other pixel-value mappings, is non-trivial in that such mappings are normally applied to contone images and not to blurred halftoned images. The pixel-value mappings of the present invention are derived via an iterative process. Alternatively, a model for this modulated image type is used.