3. Calculation method of background color removal In the analog electronic color separation machine, due to the use of a suitable image processing method for background color removal, that is, the neutral gray component in the dark-tone composite color can be separately extracted, so that the background color removal function can be accurately, quickly, and easily realized . As can be seen from the analysis in Figure 4-4-3, the background color removal is essentially to perform a certain transformation on the composite color area, replace the color with black, and reduce the amount of tri-color ink, so the calculation method is similar to the black version calculation, but more emphasis on color The size of the saturation is usually limited to the background area of ​​the image with low saturation. The simulation operation equation is: S-means min (Vy, Vm, Vc) Δ = L-S represents the saturation of the composite color, K reflects the degree of influence of saturation on the black plate, and the larger the K, the smaller the degree of influence of saturation on the black plate. In the actual use of background color removal, it is necessary to take into account both the background color removal range and the background color removal amount, and its value range is determined by actual work. In some electronic color separation machines, the following formula is used to calculate the amount of background color removal. Dr-copy density range In the background color removal calculation, the K value is usually taken as 5, so that the influence of the convexity on the amount of background color removal is enhanced, and the area where the background color removal effect is significant is located near the neutral gray of the original. In the saturated or solid color area, the background color removal is very small, or even no, thus ensuring the bright and vivid of the original picture, avoiding the phenomenon of darkening or winning due to the increase of the black version, and determining the amount of background color removal At the same time, you also need to select the appropriate background color to remove the starting point. 4. Process characteristics of background color removal When the UCR color separation mode is selected, the settings are only two technical indicators: black ink limit and total ink amount, usually the total ink amount is limited to about 260%, and the starting point of the black plate is basically fixed at about 50%. By adjusting the two technical indicators of black ink limit and total ink amount, the amount of UCR removal will have different changes, and at the same time, the starting point of UCR removal will also change according to the total ink limit. UCR is suitable for most manuscripts and printing processes, especially the gravure printing process and the characteristics of manuscripts require bright and dense colors. Therefore, it is more suitable for the UCR color separation mode. The black ink limit parameter value can be smaller, for example, choose 60%, three primary colors More ink is more advantageous. (3) Characteristics of Ash Replacement (GCR) Any color separation mode has its own characteristics. The technical nature of the color separation personnel is that when selecting the color separation mode, it is necessary to understand its characteristics in order to give full play to its advantages and make up for its shortcomings; it must also be familiar with printing expertise and master the characteristics of the original, so that high-quality originals can be reproduced. 1. GCR process points ①Make full use of the black version and make a long-order black version from 0% to 100%; ③ Use black ink to replace the gray color in the image, that is to say use black ink to replace the complementary color ink. 2. Advantages of GCR ①Reducing the total amount of four-color superimposed ink is conducive to the drying of ink, which is convenient for high-speed multi-color printing; ②It is beneficial to achieve the printing gray balance, which can ensure the reproduction and stability of gray tones; 3. GCR deficiency ①When replacing the smallest primary color with gray color with black ink, the basic color of the color will also be reduced, resulting in insufficient depth primary color saturation, as shown in Figure 4-4-3. It can be seen from Figure 4-4-3 that when 20% K replaces the minimum primary color C 20%, the basic colors Y and M of the hue are also lightened by 20%, so the color separation personnel are important in encountering the original When using the dark primary colors, use the Photoshop tool to deepen the lightened dark primary colors in order to achieve sufficient saturation. ②Because the long-order black version uses black to replace the complementary color in the color, its transparency is worse than the complementary color, so it has an impact on the vividness of the color, and the black version should be appropriately lightened and adjusted.
After
a hard working day, you went home, Pour a glass of wine, Seating on the bistro
chair and table, peering ahead, find opportunities for encounter your mind.
Transform your outdoor space with our range of
bistro tables, chairs & sets at golden eagle. We have something to suit
every household - find charming, compact bistro tables for city balconies or
large rattan armchairs for big back gardens so you can stretch out and read the
paper under the sun.
·
UV-resistant
polyethylene environmental rattan
·
Powder coated strong
no rust aluminum tube
·
Hard all kinds
of tempered
glass
·
Cushions with 100% waterproof fabric.
If
you have any questions, please contact with us directly. Outdoor Sofa Furniture
are produced by Golden Eagle Outdoor Furniture With High Quality and Good
Appearance. Welcome you can visit our Factory.For any inquiry,Please send mail
directly to us.
Bistro Chair And Table,Garden Bistro Chair And Table,Patio Bistro Chair And Table,Rattan Bistro Chair And Table Golden Eagle Outdoor Furniture Co., LTD. , https://www.gegardensets.com
R ï¼ Sï¼Lï¼S / K ï¼ Sï¼Î” / K
Among them: R-represents the amount of background color removal L-represents max (Vy, Vm, Vc)
R = removal density / replication density range × 100% = DR / Dr × 100%
Among them: DR——removal density
The disadvantage of UCR is that the dark primary colors with more ash content will be affected by the removal and cause insufficient saturation. Therefore, when there is an important dark primary color in the image, you need to use Photoshop tools for local correction to make it reach sufficient saturation.
â‘¡ The gray and black parts of the image are mainly reproduced by black ink, and the gray components composed of the three primary color plates of C, M and Y are removed. In other words, black ink is used to replace the gray and black composed of the three primary color balances in the traditional process to achieve the consistency of optical and visual effects;
â‘¢ Replace the expensive color ink with low-cost black ink, which can reduce the ink cost. 
