The principle and usage of Photoshop filter

One, what is a filter?

The filter is originally a photographic device, as shown in the following picture: The photographer installs them in front of the camera to change the way the photos are taken, to influence the color or to produce special effects.

A filter in Photoshop is a plug-in module that can manipulate pixels in an image. Bitmaps (such as photos, image footage, and so on) are made up of pixels, each with its own position and color value, and the filter creates a variety of special effects by changing the position or color of the pixel.

　　Ii. types and main uses of filters

Filters are divided into built-in filters and plug-in filters in two broad categories. Built-in filters are the kinds of filters that Photoshop itself provides, and the plug-in filters are filters developed by other vendors that need to be installed in Photoshop to be used.

All of the filters in Photoshop are shown in the Filter menu as follows

Photoshop's built-in filter has two main uses, one for creating specific image effects, such as the production of chalk, stamps, textures, waves and other special effects. The maximum number of such filters, and most of them in the "style", "sketch", "texture", "pixel", "rendering", "art effect" and other filter groups, in addition to "twist" and a few other filters, basically through the "Filter Library" to manage and apply.

The second category is used primarily for editing images, such as reducing noise, improving sharpness, and so on, in filter groups such as Blur, sharpen, and noise. In addition, "liquefaction", "Vanishing Point", "lens correction" also belong to this kind of filter. These three kinds of filters are special, they are powerful, and have their own tools and unique methods of operation, more like stand-alone software.

　　Third, the use of filters rules

1, when the filter processes the layer, you need to select the layer, and the layer must be visible.

2, if you create a selection, the filter processes only the images within the selection, as shown in the figure.

3, the filter processing effect is measured in pixels, so the same parameters to handle different resolution of the image, the effect will be different.

4, filters can handle layer masks, quick masks, and channels.

5, only the "cloud" filter can be applied to areas with no pixels, and other filters must be applied to areas that contain pixels, otherwise they cannot be used. Except for external filters.

　Four, the use of filter techniques

1, after we finish executing a filter command, the name of the filter appears on the first line of the filter menu, as shown in the following figure: click it or press Ctrl+f to quickly apply the filter. If you want to adjust the parameters of the filter, you can press ctrl+alt+f shortcut to open the Filter dialog box to reset the parameters.

2, holding down the ALT key in any Filter dialog box, the Cancel button changes to the reset button and clicks it to restore the parameter to its original state.

3, in the process of applying a filter, you can press ESC if you want to terminate the processing.

4, when using the filter, the Student guild opens the filter processing library, or the corresponding dialog box, in the Preview box you can preview the filter effect, click the +, the-button to zoom in and out, click and drag the image in the preview box, you can move the image, if you want to see an image of a range, you can click in the document, The image that is clicked is displayed in the Filter preview box.

5, after you use the filter to process the image, the Edit > Fade command allows you to modify the blending mode and opacity of the filter effect. The fade command must be executed immediately after an edit operation, and if another operation is performed in the middle, the command cannot be executed.

　　V. View the filter information

The Help > About Plug-ins drop-down menu contains a directory of all of the filters and plug-ins in Photoshop, and if you choose any one, he displays its details, such as filter book, creator, owner, and so on. The following figure shows the relevant information for the Filter gallery.

VI. Improve filter performance

Some of the filters in Photoshop use a lot of memory, such as "lighting effects", "woodcut", "stained glass" and so on, especially when editing high-resolution images, Photoshop processing speed is very slow, in this case should free memory

Vii. Browse online filters to perform the browse online filters command on the Filter menu. You can link to the Adobe Web site to find the filters and plug-ins you need.

Category:

• PS Filter Tutorial