Photoshop pen tool cutout and layer fill
PS commonly used matting methods
The so-called "cutout" refers to the part of the picture that needs to be processed as a selection for processing.
The commonly used cutout methods in PS are:
1. Lasso tool method-the easiest way to cut out
2. Quick selection method-computer intelligent selection, available where the color difference is obvious
3. Pen tool method -the most precise cut Figure method
4. Color range method—combined with other methods to play a supplementary role
5. Plug-in method (not recommended)
When processing sonar images, there are often pictures that are difficult to identify by the computer and require manual fine-graining. For this type of picture, In theory, the pen tool method must be used. This article mainly explains the pen tool cutout method.
Pen tool
1. Tool function: Pen tool is a tool for drawing lines .
2. The pen tool can be used to cut out images because when the line drawn by it is used as a path , the range framed by the line can be converted into a selection.
3. The pen tool can draw straight lines or curves.
4. The curve drawn by the pen tool is a Bezier curve (this article will talk about it shortly).
5. The important reason why the pen tool is difficult to use is that the feel of drawing Bezier curve takes a period of operation to develop. It needs to be explored at the beginning, but once it is raised, it will be handy. The process of developing a hand feel generally does not exceed 2 days.
6. The main steps of the pen tool to cut out: use straight lines and curves to convert the part of the frame to be selected.
Bezier curve
The figure below is a complete Bezier curve structure diagram. ( This module explains only line knowledge, PS operation will be covered in this article. )
1. Bezier curve is composed of lines and nodes , and nodes and nodes are connected by line segments or curves.
2. Each node connected to the curve has two control points .
3. By adjusting the control points, the shape of the curve can be changed.
4. The connection between the node and the control point is called the control line . The control line is the tangent of the curve at the node and determines the direction of the curve.
5. The length of the control line determines the degree of curvature of the curve. As with all lines, the longer the control line, the more curved the curve.
6. In PS, what we can control is: the number of nodes, the location of each node, the location of each control point, and whether each control point plays a role.
After some geometric analysis, it is easy to prove the following conclusions:
1. Bezier curve must pass through all its nodes.
2. Change the position of any control point, the shape of the line must change.
3. Through the control of several data in the 6th point above, it is possible to draw line segments, curves and combinations of any shape in the two-dimensional space.
The above three theoretical conclusions have inspired our practical operations:
1. According to the first one, if we want to draw a Bezier curve, we need to place all the nodes in the position where the line must pass .
2. According to the second article, we need to adjust the shape of the curve by adjusting the control points of each node .
3. According to Article 3, we are confident when we cut out pictures .
Draw Bezier curve matting with pen tool in PS
1. Preliminary steps
1. Open PS, open the picture.
This method is applicable to all Photoshop versions. The version I use is Photoshop 2021 windows version.
2. Switch to the pen tool (shortcut key: P).
If the pen tool (like mine) is already selected when it was opened in the first step, it means that the pen tool was selected when it was closed last time, and there is no need to select it again.
3. In the upper left corner, select the pen tool mode as "path"
Second, draw the Bezier curve
Noun description: The "node" in the Bezier curve is called the "anchor point" in the PS pen tool, and there is no difference between the two; the "control point" of the Bezier curve is also called the "adjustment point" in the PS.
Button description (browse briefly, use later):
New line segment anchor point: Left-click at the location to be created.
New curve anchor point: Left-click at the location that needs to be created and drag out the adjustment point to
move the anchor point: Ctrl+left button to drag the anchor point to be moved
Fine-adjust the position of the anchor point: arrow keys
Move the adjustment point: Alt+left button to drag the adjustment point to be moved
Delete the just created anchor point: Right click-delete the anchor point, or directly Ctrl+Z to cancel
Delete the anchor points in the path: Left-click on the anchor point to be deleted
. Create a new anchor point in the path line: Left-click on the line.
Select all anchor points: Ctrl+Alt+Left click to
make the control point of the node align The next direction does not work: Alt+left click on the node
Operation steps:
1. Alt+mouse wheel, zoom the picture to the size suitable for cutting out, and adjust it to the position to be cut out
2. Left-click on any position on the outline that needs to be cut out, the first anchor point blue will appear
The little colored dot is the anchor
3. The anchor point and the root of the cat’s ear are approximately straight line segments. Click to generate a second anchor point and automatically connect it to the first line segment
. 4. If you want to draw a line segment, repeat the steps and automatically connect to the previous one.
5 Next is a curve arc, left-click on the other end of the arc to establish a curve anchor point and adjust it accordingly. Adjustment essentials: The control line is the connection between the control point and the node. The control line is the tangent of the curve. The length of the control line determines the curvature of the curve. The
control line will naturally be pulled out when dragging. The control line is also a blue line, but not a curve. Don’t confuse it with the curve.
The nodes are square points and the control points are round points.
If the curve does not fit well enough, you can Alt+Left button drag on the control point. Note that the control point to be dragged at this time is often not the one that was naturally dragged out just now. It should be: wherever the curve comes from, drag the control point on which side. Remember to hold down Alt, if you don’t press and drag directly, a new node will be created.
6. Next is another small arc. According to the control line, it is a tangent line. If you connect another cat's ear root with a curve, it will be tangent to this control line. This is obviously not the effect we want (you can try it). For this reason, we have to let this node decide the next control line does not play a role. Hold down Alt and click on the node.
7. Create a point and draw a line at the root of another ear.
8. Obviously, it cannot be tangent out, and then make it invalid.
9. Repeat
10. Go to the control point and repeat
11. The following part , Because the cat’s body contour is covered by grass, it can be approximated as a straight line. Still remove the control points and click directly to create a node.
12. Then you can repeat the steps continuously until the frame is complete. In fact, in the process, we can find that there are actually only two types of lines, line segments and arcs, which can be continuously connected, and the nodes are the end points of the line segments and arcs. In the process of drawing the line, you can still Alt+mouse wheel to zoom in and out. If the node position is not right, you can Ctrl+left-click to drag and adjust. Do this until the last anchor point is close to the initial anchor point.
13. When the contour between the last anchor point and the initial anchor point is a straight line segment, or when the distance is very close, it can be approximated as a straight line segment, remove the control point, click on the initial anchor point, and connect with it to frame the whole Cat.
14. Right-click on the cat-create a selection (or click "Selection..." in the "Create" column above)
15. The selected selection may be a cat, or it may be everything except cats. If there is a dotted line in the border of the entire picture, it means that the selection is everything except the cat. Press Ctrl+Shift+I to reverse the selection (or the upper menu bar-select-select reverse). So
far, the cutout operation is complete. Sonar image processing also requires the following steps.
Three, selection operation
1. Ctrl+J to copy the selected area to a new layer (if the original layer is the background, it is better to convert it to a normal layer first, and drag the lock into the trash can)
2. Left click to select the copied layer (just After copying, it is selected by default), here is layer 2, press Shift+F5 (or menu bar-edit-fill), select white for content (if the current foreground color is white, select the foreground color), the mode is normal, The opacity is 100%, and the transparent area should be checked. determine
3. Left-click to select the original layer, here is layer 1, press Shift+F5 (or menu bar-edit-fill), select black for the content (if the current background color is black, select the background color) , The mode is normal, the opacity is 100%, and the transparent area can be reserved without tick. OK
4. Image processing is complete, you can save as jpg.
This article is completely original, and some pictures are from the Internet. If reproduced, please indicate source.