公开(公告)号：US5657137A

公开(公告)日：1997-08-12

申请号：US438294

申请日：1995-05-10

申请人： Alexander Perumal, Jr. ,  Paul H. Dillinger

发明人： Alexander Perumal, Jr. ,  Paul H. Dillinger

IPC分类号： H04N1/52 ,  H04N1/60 ,  H04N1/54

CPC分类号： H04N1/6022 ,  H04N1/52 ,  H04N1/60 ,  H04N1/6016

摘要： This system selectively enables a printer to deposit primary or black color dots at pixel locations on a sheet to produce a color image--in such a way as to increase the overall number of dots used in the image, thereby minimizing contrast between dots on the sheet and adjacent areas and so providing a better simulation of a continuous-tone image. The result is print quality often near that of error diffusion, usually better than any dither technique, but with the greater speed of a dither technique. The system includes a memory for storing a first color vector for each pixel in the image, respectively, and a processor coupled to the memory for determining a second color vector from each of the first vectors, respectively. The processor accomplishes this determination by replacing a fraction of the black color component of the first vector with primary colors. Preferably the processor also removes from the first color vector a quantity of white, in conjunction with the black replacement; in this case the processor sets the fraction of the black component to a value between zero and one inclusive, depending on the quantity of white that is available, in the first color vector, for removal. Preferably the fraction is the smaller of (1) the quantity of black present and (2) a certain fraction of the quantity of white available for removal. Analogously a fraction of the secondary color component of a color vector is replaced with primary colors.

摘要翻译： 该系统选择性地使得打印机能够在纸张上的像素位置处存储主要或黑色彩色点以产生彩色图像，以便增加图像中使用的点的总数，从而最小化纸张上的点之间的对比度 和相邻区域，因此提供了对连续色调图像的更好的模拟。 结果是打印质量通常接近于误差扩散的质量，通常比任何抖动技术都好，但抖动技术的速度更快。 该系统包括用于分别存储图像中的每个像素的第一颜色矢量的存储器和耦合到存储器的处理器，用于分别从每个第一矢量确定第二颜色矢量。 处理器通过用原色代替第一矢量的黑色分量的一部分来完成该确定。 优选地，处理器还与第一颜色矢量一起从黑色替换中移除一定数量的白色; 在这种情况下，处理器将黑色分量的分数设置为包含0和1之间的值，具体取决于第一个颜色矢量中可用的白色数量以进行删除。 优选地，部分是（1）黑色存在量和（2）可用于去除的白色数量的一定比例中的较小者。 类似地，颜色矢量的次要颜色分量的一部分被原色代替。

公开(公告)号：US5917994A

公开(公告)日：1999-06-29

申请号：US909747

申请日：1997-08-11

申请人： Alexander Perumal, Jr. ,  Paul H. Dillinger

发明人： Alexander Perumal, Jr. ,  Paul H. Dillinger

IPC分类号： H04N1/52 ,  H04N1/60 ,  H04N1/56

CPC分类号： H04N1/6022 ,  H04N1/52 ,  H04N1/60 ,  H04N1/6016

摘要： This system selectively enables a printer to deposit primary or black color dots at pixel locations on a sheet to produce a color image--in such a way as to increase the overall number of dots used in the image, thereby minimizing contrast between dots on the sheet and adjacent areas and so providing a better simulation of a continuous-tone image. The result is print quality often near that of error diffusion, usually better than any dither technique, but with the greater speed of a dither technique. The system includes a memory for storing a first color vector for each pixel in the image, respectively, and a processor coupled to the memory for determining a second color vector from each of the first vectors, respectively. The processor accomplishes this determination by replacing a fraction of the black color component of the first vector with primary colors. Preferably the processor also removes from the first color vector a quantity of white, in conjunction with the black replacement; in this case the processor sets the fraction of the black component to a value between zero and one inclusive, depending on the quantity of white that is available, in the first color vector, for removal. Preferably the fraction is the smaller of (1) the quantity of black present and (2) a certain fraction of the quantity of white available for removal. Analogously a fraction of the secondary color component of a color vector is replaced with primary colors.

摘要翻译： 该系统选择性地使得打印机能够在纸张上的像素位置处存储主要或黑色彩色点以产生彩色图像，以便增加图像中使用的点的总数，从而最小化纸张上的点之间的对比度 和相邻区域，因此提供了对连续色调图像的更好的模拟。 结果是打印质量通常接近于误差扩散的质量，通常比任何抖动技术都好，但抖动技术的速度更快。 该系统包括用于分别存储图像中的每个像素的第一颜色矢量的存储器和耦合到存储器的处理器，用于分别从每个第一矢量确定第二颜色矢量。 处理器通过用原色代替第一矢量的黑色分量的一部分来完成该确定。 优选地，处理器还与第一颜色矢量一起从黑色替换中移除一定数量的白色; 在这种情况下，处理器将黑色分量的分数设置为包含0和1之间的值，具体取决于第一个颜色矢量中可用的白色数量以进行删除。 优选地，部分是（1）黑色存在量和（2）可用于去除的白色数量的一定比例中的较小者。 类似地，颜色矢量的次要颜色分量的一部分被原色代替。

公开(公告)号：US5473446A

公开(公告)日：1995-12-05

申请号：US189541

申请日：1994-01-27

申请人： Alexander Perumal, Jr. ,  Paul H. Dillinger

发明人： Alexander Perumal, Jr. ,  Paul H. Dillinger

IPC分类号： B41J2/525 ,  B41J5/30 ,  H04N1/46 ,  H04N1/52 ,  H04N1/60 ,  H04N1/64

CPC分类号： H04N1/60 ,  H04N1/52 ,  H04N1/6016 ,  H04N1/6022 ,  H04N1/6058

摘要： Provided is a system and method for selectively enabling a printer to deposit on a sheet cyan, magenta, yellow and black (C,M,Y and K) primary or black color dots at each of the plurality of pixel locations to produce a color image. The system comprises a memory for storing C, M, Y and K values for each pixel in the color image and a processor for controlling selective deposition of the C, M, Y and K colors. The system includes a memory for holding a color vector for each pixel, respectively in the color image; a memory for storing parameters of a dither cell; and a processor coupled to the memory for comparing the dither cell with each color vector, to select a color component to print at the corresponding pixel location based on the comparison. The system provides a halftoning technique that produces print quality near error diffusion quality with the speed of a dither by dithering on a color vector. The replacement of black and secondary colors by the system produces better print quality than other dither techniques.

摘要翻译： 提供了一种用于选择性地使得打印机能够在多个像素位置中的每一个处沉积在青色，品红色，黄色和黑色（C，M，Y和K）原色或黑色色点上的片材以产生彩色图像的系统和方法 。 该系统包括用于存储彩色图像中的每个像素的C，M，Y和K值的存储器和用于控制C，M，Y和K颜色的选择性沉积的处理器。 该系统包括分别在彩色图像中保持每个像素的颜色矢量的存储器; 用于存储抖动单元的参数的存储器; 以及处理器，其耦合到所述存储器，用于将所述抖动单元与每个颜色矢量进行比较，以基于所述比较来选择在相应像素位置处打印的颜色分量。 该系统提供了一种半色调技术，通过在颜色矢量上抖动来产生抖动速度，误差扩散质量附近产生打印质量。 系统替换黑色和次色可以产生比其他抖动技术更好的打印质量。

公开(公告)号：US5710827A

公开(公告)日：1998-01-20

申请号：US558560

申请日：1995-10-31

申请人： Alexander Perumal, Jr. ,  Qian Lin

发明人： Alexander Perumal, Jr. ,  Qian Lin

IPC分类号： B41J2/52 ,  B41J2/21 ,  B41J2/525 ,  G06F3/12 ,  G06T1/00 ,  G06T5/00 ,  G09G5/00 ,  G09G5/02 ,  H04N1/405 ,  H04N1/52 ,  G03F3/08 ,  H04N1/40 ,  H04N1/46

CPC分类号： H04N1/52

摘要： Methods and apparatus generate, and use in printing, a dither matrix that incorporates a vivid-response function, that follows a generally S-shaped response curve. Printing with this pregenerated dither cell is just as fast as with a conventional cell, but printed color has a slightly exaggerated vividness, more pleasing to most users than more-accurately reproduced color. Color printed with this curve alone, however, is found unsatisfactorily dark; the invention also encompasses including in the overall response another function to lighten the colors--particularly at the low end of the brightness range. We define both functions as so-called "gamma functions", but with different arguments and exponents, and construct the S-shaped curve as two separate sections blended at a generally central point. Preferably the argument of the first (low-brightness) section is an expression that is proportional to an input color signal; the function raises this argument to a power greater than unity (ideally 1.6). The second (high-brightness) section of the first function is essentially a mirror image of the first, flipped over first upward and then to the "right" (i.e., in both steps toward higher brightness); and is defined by an equation closely analogous to the first but measuring the signal from the high end of the input range and subtracting the curve value from the maximum output. The second gamma function has as its argument the output value of the first, and an exponent smaller than one--ideally 0.6.

摘要翻译： 方法和装置在打印中产生并使用包含生动响应函数的抖动矩阵，其遵循大致S形的响应曲线。 用这种预生成的抖动单元打印与传统单元格一样快，但印刷颜色稍微夸张的鲜明度，对大多数用户来说比更准确地再现的颜色更令人愉快。 然而，用这条曲线单独打印的颜色被发现不太令人不快; 本发明还包括在整体响应中包括减轻颜色的另一功能，特别是在亮度范围的低端。 我们将这两个函数定义为所谓的“伽玛函数”，但是具有不同的参数和指数，并且将S形曲线构造为在一般中心点处混合的两个单独的部分。 优选地，第一（低亮度）部分的参数是与输入颜色信号成比例的表达式; 该函数将这个参数提升到大于单位的力（理想情况下为1.6）。 第一功能的第二（高亮度）部分基本上是第一个的镜像，首先向上翻转，然后翻转到“右”（即，在两个步骤中朝向更高的亮度）; 并且由与第一个方程密切相似的方程定义，但是测量来自输入范围的高端的信号并从最大输出中减去曲线值。 第二个伽玛函数的参数是第一个的输出值，一个指数小于一个，理想的是0.6。