Topic
Dot gain
About: Dot gain is a research topic. Over the lifetime, 479 publications have been published within this topic receiving 4456 citations.
Papers published on a yearly basis
Papers
Patent•
8 Apr 1994TL;DR: In this paper, a system for dot overlap correction of halftone images at a digital printer which is coupled to multiple computers in a network is presented. But the system is not suitable for the use of multiple computers.
Abstract: Halftone correction systems are provided for producing dot overlap corrected halftone images at a digital printer. In the first embodiment, a system is provided for halftone correction on a black-and-white digital printer. The system first calibrates the black-and-white digital printer with seven test patterns to provide halftone correction information. Multi-level digital image signals representing a continuous-tone image are then received and stored. The system next halftones these multi-level digital image signals to provide an overlap corrected halftone image responsive to the halftone correction information at the digital printer. Halftoning is performed using an overlap corrected ordered dithering screen, which was generated based upon the correction of the partial overlap of adjacent dots in an uncorrected ordered dithering screen. In the second embodiment, a system is provided for producing dot overlap corrected color halftone images on a digital color printer. The system first calibrates the digital color printer with a set of color test patterns to provide halftone correction information. Next, multi-level digital color image signals representing a continuous-tone color image are received and stored. The system then halftones the multi-level digital color image signals to provide an overlap corrected color halftone image responsive to the halftone correction information at the digital color printer. The system may halftone the continuous-tone color image by either color error diffusion or ordered dithering techniques. In the third embodiment, a system is provided for dot overlap correction of halftone images at a digital printer which is coupled to multiple computers in a network.
208 citations
Patent•
26 Nov 2003
TL;DR: In this paper, the authors describe methods for using embedded auxiliary signals in documents for copy detection and other applications, where the auxiliary signal is formed as an array of elements selected from a set of print structures with properties that change differently in response to copy operations.
Abstract: This disclosure describes methods for using embedded auxiliary signals in documents for copy detection and other applications. In on application, the auxiliary signal is formed as an array of elements selected from a set of print structures with properties that change differently in response to copy operations. These changes in properties of the print structures that carry the embedded auxiliary signal are automatically detectable. For example, the changes make the embedded auxiliary signal more or less detectable. The extent to which the auxiliary data is detected forms a detection metric used in combination with one or more other metrics to differentiate copies from originals. Examples of sets of properties of the print structures that change differently in response to copy operations include sets of colors (including different types of inks), sets of screens or dot structures that have varying dot gain, sets of structures with different aliasing effects, etc. Robust and fragile watermarks are used in Image Replacement Documents for a variety of applications. Digital watermarks act as on-board mediators in authentication of a variety of printed documents. Finally, digital watermarks are used to help manage quality of the scanners used in imaging systems.
139 citations
Patent•
2 Nov 1990TL;DR: In this article, a multiple pass complementary dot pattern ink jet printing process was proposed to enhance the uniformity and consistency of dot (1-16) formation during color ink jet print.
Abstract: A multiple pass complementary dot pattern ink jet printing process for enhancing the uniformity and consistency of dot (1-16) (drop) formation during color ink jet printing. Such enhancement in turn directly affects and improves the total print quality over a color printed area by minimizing the undesirable characteristics of coalescence, beading, hue shift, banding, cockeling and color bleed when printing on both transparencies and plain or special papers. Using this process, successive printed swaths are made by depositing first and second partially overlapping complementary dot patterns (10,14) on a print media. Simultaneously, the dot (1-16) spacing in coincident dot rows (12) within the overlapping portions of the dot patterns (10,14) is alternated between dots (1-16) in the first pattern (10) and dots (1-16) in the second pattern (14). This invention is also directed to the novel process of combining complementary pass ink jet printing as described above with dot-next-to-dot (DND) super pixeling (Figures 3A-3C) in order to further optimize the ink drop drying conditions desirable for producing the above optimized uniformity and consistency of dot formation over a given color printed area.
124 citations
24 Jul 1994
TL;DR: In grayscale wedges produced by rotated dither, texture changes at consecutive gray levels are much smoother than in error diffusion or in Bayer's dispersed-dot dither methods, thereby avoiding contouring effects.
Abstract: Rotated dispersed-dot dither is proposed as a new dither technique for digital halftoning. It is based on the discrete one-to-one rotation of a Bayer dispersed-dot dither array. Discrete rotation has the effect of rotating and splitting a significant part of the frequency impulses present in Bayer's halftone arrays into many low-amplitude distributed impulses. The halftone patterns produced by the rotated dither method therefore incorporate fewer disturbing artifacts than the horizontal and vertical components present in most of Bayer's halftone patterns. In grayscale wedges produced by rotated dither, texture changes at consecutive gray levels are much smoother than in error diffusion or in Bayer's dispersed-dot dither methods, thereby avoiding contouring effects.Due to its semi-clustering behavior at mid-tones, rotated dispersed-dot dither exhibits an improved tone reproduction behavior on printers having a significant dot gain, while maintaining the high detail rendition capabilities of dispersed-dot halftoning algorithms. Besides their use in black and white printing, rotated dither halftoning techniques have also been successfully applied to in-phase color reproduction on ink-jet printers.
118 citations
Patent•
11 Jan 1999TL;DR: In this paper, a method and apparatus for producing halftone images which utilizes the advantageous stochastic patterning of dots found in frequency-modulated, blue-noise masks, and avoids the problem of dot gain provided in amplitude modulated masks is presented.
Abstract: A method and apparatus for producing halftone images which utilizes the advantageous stochastic patterning of dots found in frequency-modulated, blue-noise masks, and avoids the problem of dot gain provided in amplitude-modulated masks. Here a green-noise spectrum is used to generate a dither mask and the halftone patterns for each gray-level are subjected to the stacking constraint. The filters used in building the green-noise masks comprise filters using the conventional blue-noise mask for a coarseness parameter M′(g)=1 and filters having a principle frequency fg less than the principle frequency of blue-noise fb when coarseness parameter M′(g)>1. Unlike blue-noise dither patterns, green-noise dither patterns comprise pixel clusters, making them less susceptible to image degradation from dot gain, generating dot-profiles that are visually pleasing to the human eye.
109 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2021 | 1 |
| 2020 | 4 |
| 2019 | 5 |
| 2018 | 5 |
| 2017 | 8 |
| 2016 | 7 |