How to deduce the map

Drawing deduction method is as follows:

1, PS magic wand mat

Open PS, click the magic wand tool, put a tick in front of the "continuous" item, adjust the "tolerance" value, click the background color to appear a virtual box to surround the background color, deselect the selection, execute the copy and paste command, and close the eyes of the background layer. It is very practical for some transparent objects.

2, PS color range matting

Turn on PS, pick up the background color with the color straw, click the color range function in the menu "Select" function, tick the "Inverse" item, set the tolerance value, and confirm to get the image. It is very practical for simple chromatic aberration graphics with obvious background color.

3.PS magnetic lasso method for matting

Open PS, right-click the Lasso tool, select the Magnetic Lasso tool, and place boundary points along the image boundary. A line will be automatically generated between two points and attached to the image boundary. When the lasso is closed, the incision is completed. It is very useful for clear image boundaries (such as polygon graphics).

4, PS pen tool matting

Open PS, and when the image boundary is complex and discontinuous, use the pen tool for matting. Select the pen tool and select the icon of the second "path" in the pen toolbar; Right-click "Create Selection", generally fill in "0" and press CTRL+C to copy the selection; Create a new layer or file; In the new layer, press CTRL+V to paste the selection.

Each node has two radian adjustment points. Adjusting the radian between the two nodes makes the straight line as close as possible to the edge of the graph, which is the key step of smoothing. When the pen is closed, the mat is finished. For images with complex and discontinuous boundaries, the algorithm has high processing accuracy.

Importance of matting

"matting" is one of the most common operations in image processing. Accurately extracting the required part of an image from a picture is called matting, which is an important basis for subsequent image processing.

The main function is to prepare for the later synthesis. Methods include lasso tool, box selection tool, eraser tool, quick mask, pen sketching path and then turning to the selection, drawing filter, drawing external filter, channel, calculation, applying image method and so on.