Principle calculation formula of Photoshop layer blending mode?

In Photoshop 7.0, the layer blending options are linear deepening mode, linear thinning mode, bright mode, linear light mode and point light mode, which can make some effects more convenient.

Here we take the Chinese version of Photoshop 7.0 as an example to introduce the "layer blending mode" of Photoshop. Except for a few new blending modes, the other blending modes are the same as the lower version of Photoshop. For the convenience of friends who use the English version of Photoshop, we will also give Chinese and English keywords. I think everyone is familiar with the "layer blending mode". As shown in figure 1, it is the blending option of the layer. When different layers are superimposed together, in addition to setting the opacity of the layers, the mixing method of the layers will also affect the superposition effect of the two layers. In the open list, you can see a series of familiar mixed modes. In Photoshop 7.0, you can see mixed-mode menus, such as Fill, Stroke and Calculate. In fact, their principles are actually the same and the methods used are basically the same.

1. Natural oscillation

In Normal mode, the display of "mixed color" is related to the setting of opacity. When the "opacity" is 100%, that is, it is completely opaque, the pixels of the "result color" will be completely replaced by the used "mixed color"; When the opacity is less than 100%, the mixed pixels will be displayed by the color used, and the degree of display depends on the opacity setting and the color of the base color, as shown in Figure 5, which is the effect after the opacity is set to 90%. If you are working with a bitmap color mode image or a indexed color color mode image, the Normal mode will be renamed to the Threshold mode, but the function will be the same.

2. Dissolution mode

In "Dissolve" mode, it is mainly to make each pixel become "result color" when editing or drawing. However, according to the opacity of any pixel position, the "result color" is randomly replaced by "primary color" or "mixed color" pixels. Therefore, the "Dissolve" mode is best used with some coloring tools in Photoshop, such as "brush", "imitation stamp" and "eraser", and words are also acceptable. When the "mixed color" has no feathering edge and a certain transparency, the "mixed color" will dissolve into the "base color". If the mixed color has no feathering edge and the opacity is 100%, the dissolution mode is invalid. As shown in figure 6, the opacity of the mixed color is set to 90%, and there is not much difference between the mixed color and the result color, except that the edge changes a little. If "mixed colors" created by the Brush tool or text alternate with "primary colors", you can create an effect similar to diffusion jitter. If the opacity of the path is less than or equal to 50%, and then use the Stroke Path command, Dissolve mode will create a splash effect around the edge of the image, as shown in Figure 8. You can also simulate the edge of shredded paper. If you use the eraser tool, you can create a new layer on the image and fill it with white as a "mixed color". Then, in the "dissolution" mode, use the "eraser" tool to erase, and you can create the effect that the middle of the frosted glass is erased in winter.

3. Dimming mode

In dimming mode, check the color information in each channel and select the darker color in the primary color or mixed color as the result color. Pixels brighter than the "mixed color" are replaced, and pixels darker than the "mixed color" remain unchanged. The Dimming mode will cause colors brighter than the background color to be removed from the Result Color. As shown in figure 10, the white tree hanging is removed from the "result color" and the white waterfall is replaced by the color of the darker sky. If the figure 1 1 shows the cover of the Wrox reference manual series. This cover is made by setting the "mixed color" to red, then replacing the white part and white background in the "hand" with the "darkening" mode and replacing it with red.

4. Multiplication mode of positive film

In the positive overlay mode, check the color information of each channel and compound the "base color" and "mixed color". The Result Color is always a darker color. Any color combines with black to produce black. Any combination of color and white remains the same. When painting with colors other than black or white, the continuous strokes drawn by painting tools will produce gradually darkening transition colors. In fact, the positive superposition mode is to subtract the brightness value of the mixed color from the basic color to get the final result color. If you use a lighter color in the positive overlay mode, it has no effect on the "result color" of the image. You can use the "positive overlay" mode to create a slide effect in which light penetrates the layer. In fact, it is to multiply the values of "base color" and "mixed color" and then divide them by 255 to get the color value of "result color". For example, the result color of red and yellow is orange, that of red and green is brown, and that of red and blue is purple.

5. Color combustion mode

In the "color deepening" mode, check the color information in each channel, and deepen the primary colors by increasing the contrast to reflect the mixed colors. If mixed with white, it won't change. As shown in figure 14, the effect created by "color deepening" mode is similar to that created by "positive superposition" mode, except that the brighter areas on the background disappear and the image areas show sharp edges.

6. Linear combustion mode

In "Linear Deepening" mode, check the color information in each channel, and deepen the "base color" by lowering the brightness to reflect the mixed color. If the white color on the "mixed color" and "primary color" does not change after mixing,

7. Brightening mode

In the brightness enhancement mode, check the color information of each channel and select the brighter color in the primary color or mixed color as the result color. Pixels darker than the "mixed color" are replaced, and pixels brighter than the "mixed color" remain unchanged. In this mode, contrary to the "darkening" mode, the brighter color areas dominate the final "composite color". Dark areas will not appear in the final "composite color", as shown in figure 16.

8. Screen mode

The "color filter" mode is just the opposite of the "positive overlay" mode, which combines the "primary color" and "mixed color" of the image to produce a third color that is brighter than the two colors, as shown in figure 17. In fact, it is to combine the complementary color of "mixed color" with "primary color". The Result Color is always the brighter color. When filtered in black, the color remains the same. Filtering with white will produce white. Whether you use the color tool in color filtering mode or specify a layer for color filtering mode, the merged "result color" is always the same composite color or a lighter color. This effect is similar to the projection of multiple photo slides. This color filtering mode is very useful for creating a neon glow effect in an image. If you draw a layer with white or any light color around the edge of the background object, and then specify the Color Filter mode of the layer, you can get a complete or sparse lighting effect by adjusting the Opacity setting of the layer.

9. Color Fading Mode

In the color fade mode, check the color information in each channel, and fade the primary colors to reflect the mixed colors by reducing the contrast. When mixed with black, it does not change. As shown in figure 18, the Fade mode is similar to the Color Filter mode, except that the edge area of the layer is clearer in this mode, and the strokes are also colored in this mode. In addition, every time the color shading mode is defined as a pixel that mixes "mixed color" and "primary color", the dark area on the "primary color" disappears.

10. Linear Fading Mode

In "Linear Fading" mode, check the color information in each channel, and brighten the base color to reflect the mixed color by increasing the brightness, as shown in figure 19. But don't mix it with black, it won't change.

1 1. coverage mode

Overlay mode mixes the primary colors and mixed colors of an image to produce an intermediate color. The colors in the "base color" that are darker than the "mixed color" are twice as much as the "mixed color", and the colors that are brighter than the "mixed color" will cover the "mixed color", while the highlights and shadows in the image remain unchanged, so the "overlay" mode does not work when coloring black or white pixels. The "overlay" mode mixes the colors placed or applied on the layer with the background colors in an artistic and logical way, however, it can obtain interesting results. Pure black or pure white areas in the background image cannot display "superimposed" color or image areas on the layer in "Overlay" mode. Brightness values between black and white on the background area are mixed with the color of the "overlay" material to produce the final composite color. So that the background image looks like it was taken with the design or text. As shown in Figure 2 1, both the grid and the five-pointed star in Figure 22 are dissolved into the background by using the "overlay" mode. You can download PSD files for your own reference. I don't think it is necessary to introduce the specific production steps of bars, squares and pentagrams.