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From YourSITE.com *Program Basic
The selection tools in DIP9 are used to select areas of an image by a number of methods and either alter, remove or add to them. They provide control by isolating an area that can then be edited as required. Almost any task can be applied to a selection, such as adding a filter, changing only one color in the image or increasing brightness and contrast.
Each tool is designed to be useful for particular tasks. 
The Marquee tool allows selection by pre defined shapes. This tool is most useful for cropping or trimming images. To make a selection with the marquee tool: On the Stack, click the object On the toolbar, click the marquee tool button. If you can’t see the options palette, click the Selection button on the workspace toolbar. 
To maintain smooth edges along the selection, select the Anti-aliased check box on the Marquee Tool options palette. From the drop down menu, click a shape for the marquee selection. To keep the shape proportionate, select Shape proportions Most often you will want to start a new selection, but you can also add to the current selection, or subtract from the current selection. Drag the marquee pointer diagonally across the area you want to select. A dashed line appears around the selection you have made. Anything inside that line will be affected by any changes you make or apply to it. To select the opposite area of the image, click Invert on the Marquee Tool options palette. Click Adjust Marquee and make any adjustments to the size or shape of the marquee required. E.g. you can drag the square to make a rectangle or rotate the shape. Choosing feather softens the edges of an image to a value you select. This can help a selection blend into the original or new image.
The Freehand tool lets you choose an area by tracing it with a mouse or pen. It is useful for irregulary shaped objects without clearly defined edges. To make a selection with the freehand tool: On the Stack, click the object On the toolbar, click the Freehand Tool button If you can’t see the options palette, click the Selection button on the workspace toolbar. 
To maintain smooth edges along the selection, select the Anti-aliased check box on the Freehand Tool options palette. Most often you will want to start a new selection, but you can also add to the current selection, or subtract from the current selection. Zoom in on the object so your view is clear. Choose a starting point and drag your mouse or pen around the area you wish to select. If you keep the mouse button held down then the line will be drawn to follow. If you click and then move the mouse and click again a straight line will be drawn between the two points. To complete a selection return to your starting point and click on the square. A dashed line appears around the selection you have made. Anything inside that line will be affected by any changes you make or apply to it. To select the opposite area of the image, click Invert. Unfortunately the freehand tool does not allow for editing after the selection is drawn so if you make an error in selecting the area you will have to restart the process. Choosing feather softens the edges of an image to a value you select. This can help a selection blend into the original or new image.
The Edge finder creates a selection by mapping the edges of an object. It is best used when the object you want to select has clear and distinct edges. To make a selection with the Edge Finder tool: On the Stack, click the object On the toolbar, click the Edge Finder Tool button If you can’t see the options palette, click the Selection button on the workspace toolbar. 
To maintain smooth edges along the selection, select the Anti-aliased check box. The pixel edge width can be determined by you by decreasing or increasing as desired. The width is the number of pixels away from the pointer that the Edge Finder will try to detect an edge. Most often you will want to start a new selection, but you can also add to the current selection, or subtract from the current selection. Zoom in on the object so your view is clear. Choose a starting point and click around the area you wish to select. You need to keep the edge within the boundaries of the tool. By keeping the edge in the center you will get the best results. If you keep the mouse button held down then the line will be drawn to follow. If you click and then move the mouse and click again a straight line will be drawn between the two points. To complete a selection return to your starting point and click on the square. A dashed line appears around the selection you have made. Anything inside that line will be affected by any changes you make or apply to it. To select the opposite area of the image, click Invert. You can adjust your selection by choosing Adjust edges. You can either move the square anchor points as desired or click on any part of the line to create a new anchor point that can then be moved.
The Magic Wand selects areas by color. It is useful for choosing areas of the same or similar color so you don’t have to draw around them. To make a selection with the Magic Wand tool: On the Stack, click the object On the toolbar, click the magic Wand Tool button If you can’t see the options palette, click the Selection button on the workspace toolbar. 
Choose the Contiguous option if you want to select only areas of color that are connected to each other. Deselect the box to select all areas of that color in the image. Choose a tolerance level where 0 selects only pixels of identical color, and 255 selects all the pixels in the object. If the selection has includes too much or too little of the area you want to select, enter a different value in the Tolerance box, and then make another selection. Most often you will want to start a new selection, but you can also add to the current selection, or subtract from the current selection. To select the opposite area of the image, click Invert.
To alter an image with any tool, the process is the same. I am using the same image to demonstrate each process. 
To apply a change to an area using the Magic Wand Tool: Once you have made your selection you can make changes directly to the area by choosing almost any tool from the Format, Touchup or Effects menus for example Touchup>Brightness and Contrast. To apply the change choose Edit>Paste. This permanently applies the change directly to the image.
In this image I want to brighten the right hand bottom area where the foliage is heavily darkened. Because this area of foliage is largely uniform in color I have chosen the Magic Wand tool. I have increased the tolerance to capture the area and you can see the dashed lines appear around the selection. Now I choose Touchup>Brightness and Contrast and make my adjustments as desired. Then I select Edit>Paste to apply the change. 
To trim part of an image using the Marquee Tool Using the original image I want to remove an area to create a frame. With my image selected I select the Marquee Tool. With the square shape chosen I choose a starting point and drag out my square. The dashed lines appear around my selection but I wish to change the square to a rectangle so I select Adjust Marquee and drag the handles to form a rectangular shape as shown. Then I click Done on the palette and go to Edit>Cut to delete the inside area (you can also choose Edit>Delete) and then choose Edit>Paste. This pastes the image you have chosen to cut back in its own space. If you don’t require the image then just delete it. You may also find that the image, in this case the frame, is locked which is indicated by a small lock symbol next to the image in the stack. When an image is locked it can not be moved from its position. To Unlock the image select the image and then Edit>Unlock. 
To change part of the image using the Edge Finder Tool: The sky in the original image is not as saturated as I would like so I am going to use the Edge Finder to select that area of the photograph. I have chosen a narrow edge width because the selection area around the tree line is very uneven. I choose a starting point at the top left corner by clicking and move the mouse to the right top corner and click, keeping the edge at the center of the tool. The tool automatically draws a straight line between the two points. I repeat the process down to the tree line and then I begin to use smaller drag and clicks as indicated by the anchor points that appear later. Using smaller strokes allows the Edge Finder to find the edge with more accuracy. I continue the process until I have reached my starting point. I then chose Adjust Edges at which point the anchor points appear. I can move these if needed to ensure the edges are captured accurately. By zooming in you will get a clearer view. I have also feathered the edge by a value of 2 to better blend the final result. Then I have chosen TouchUp > Hue and saturation and made my changes. <p by then selecting editI could also choose Edit >Copy and then Edit>Paste. This would alter my image but also give me a copy of just the sky area that could be used elsewhere. 
To copy part of the image using the Freehand Tool: From the original photograph I want a section in the bottom left corner of a yellow flowering bush. To extract it I select the Freehand Tool and zoom in to that area. The Edge Finder would struggle with this task as the edges are indistinct and the area is heavily textured. Choosing a starting point I drag the tool around the edges of the area that I want to keep. The line will follow any moves you make with the mouse or pen so work slowly. If you make an error you cannot adjust the line at any point so you will have to start again (to start again move to the start point and click and then reposition the point and begin again). To copy the area choose Edit>Copy you can then paste the selection onto a new canvas or where desired. 
Tips for using the Selection Tools
* To make changes to a specific area without affecting the original image make your selection then choose Edit>Copy then Edit>Paste and you can work on that selection as a new layer in the stack. * The Edit>Undo command works to an extent with selections * If you get the message “There are no pixels in the current selection …etc” you can simply click on the correct picture in the stack and then keep working. * If you choose a selection tool and then change your mind as to which tool you want to use simply select your choice, the tool will change * If you can’t see the options palette, click the Selection button on the workspace toolbar. * If you choose a selection tool and make a selection and then decide against the action click on the object pointer and then click anywhere on the image. * You can cut or copy and paste selections back onto the original image or onto a new canvas or other project. * The Help files contains a written and a video tutorial on using the selection tools. * Remember never work on an original photograph file. Always use a copy. © Copyright 2003-2005 by Scrapbook-Bytes; & original creator/s of tutorials/articles |