The Image Editor, shown in Figure 8-1, can create new images or edit existing ones. It is a multiple document tool allowing you to work on more than one image at the same time. The completed image is stored in an external file.
The Image Editor allows you to change the color, appearance and size of your image. An extensive set of filters, capable of manipulating whole images or just parts of them, is provided as part of the Image Editor. The filters are described at the end of this chapter. The best way to learn about the filters is try them out - the undo facility lets you do this safely on your image.
A short tutorial, demonstrating just a small sample of the capabilities of the Image Editor, follows this section. The remainder of this chapter describes each area of the Image Editor in more detail.
Figure 8-1 Image Editor
This simple step-by-step tutorial shows some of the capabilities of the Image Editor. You will create the image shown in Figure 8-2 by starting with a fresh window, giving it a textured background, adding text, embossing it, creating a drop shadow for the text and giving the appearance that the text fades out.
A Note Before you Start
During the course of this tutorial, remember that you can use the undo facility if you have tried something and you are not happy with the result. Simply select "Undo" from the Edit menu directly after an unsuccessful operation. You may also use wish to the undo feature to experiment along the way. Making frequent backups also allows you to revert to a saved image at any time.
Figure 8-2 Image Editor Tutorial - Final Image
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1. |
In the Image Editor, select "New" from the File menu. |
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This displays the Image Size dialog. |
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In the Size dialog, specify a width of 320 and a height of 140. Press OK. |
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Choose a color - something bright like pink - from the Swatches color palette. |
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Do this by clicking over the color square of your choice. The Swatches window is shown in Figure 8-9. |
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When a colour is selected from the color palette, it becomes the foreground color and is displayed in the foreground square in the bottom left corner of the Image Editor window. We are going to make this color the background color. |
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To switch over the foreground and background colors, click over the double-headed arrow above the foreground/background squares. |
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Click over another color from the palette in order to set the foreground color. |
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Choose a good contrast - green, for example. |
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In order to achieve an interesting effect on the background, select the gradient tool from the tool palette. |
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If you are not sure which one this is, look it up in Table 2 on page 118 or pass the cursor over each tool and read the Tool Tip which is displayed as you do so. |
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With the gradient tool selected, choose "Tool Properties" from the Edit menu. |
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A shortcut way of displaying this dialog is to double-click over the tool in the palette. |
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8. |
In the gradient tool Properties dialog, shown in Figure 8-15, make sure that the "Use Colormap" toggle is off and select "Conical Symmetric" from the Type list. |
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9. |
Making sure that the gradient tool is still selected on the tool palette, click in the centre of your image window and drag a line outwards to the right edge. |
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Of course, you can drag any length of line and in any direction to create different effects, but for the purposes of this tutorial you need to ensure that you have the foreground color on the right of the image. This color will be used by the gradient tool later in the tutorial. |
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You should now have an interesting "conical" effect in your new image with the foreground and then the background colors appearing to "wrap around" the window. We shall now add some text. |
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Save your image by selecting "Save" from the File menu. You are prompted for the file type. Choose one which suits you best - the Image Editor can read back in any of the formats listed. |
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It is important to save your work from time to time. |
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11. |
Select the text tool from the tool palette. |
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If you are not sure which one this is, look it up in Table 2 on page 118 or use the Tool Tips, displayed when you pass the cursor over the tools. |
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Click near the left side of your image. |
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You need to specify first where your text is going to go. When the text is placed in the image it is selected so you can move it around. Once you have clicked in your image, the text properties dialog appears, as shown in Figure 8-3. |
Figure 8-3 Text Tool Properties Dialog
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In the text tool properties dialog, specify a large font size, such as 90, choose a font that you like and type "Imagine" into the text field. |
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Although the text is displayed the correct size, the dialog may be too small to display it all. In this case, simply resize the dialog. |
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When you are happy with the size and appearance of the text in the properties dialog, press "OK". |
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The text is inserted into the image using the foreground color - the color is not important at this point as we shall be changing it using one of the filters. At this point, you can move the text by clicking inside the text and dragging it to the desired location. |
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It is important to remember at this point that the text is added as a floating selection (see the Floating Selections section on page 123 if you are not sure what this is). We need to keep it as a floating selection until we have finished with it, so do not do any other type of drawing or selecting. |
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Another point to remember is that if you are not happy with the text when it is added to the image, press "Undo" in the Edit menu and start again with the text by clicking in the image to display the text properties dialog. This applies to any drawing or filter - you can always "Undo" them and try again. |
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16. |
With your text in the image and still selected (surrounded by a red band), go to the Filters menu and choose "Shapeburst" from the Stylize pullright menu. |
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The Shapeburst dialog is displayed, as shown in Figure 8-4. |
Figure 8-4 Shapeburst Filter Dialog
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You do not need to change any of the default settings in the Shapeburst dialog, so press "OK". |
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Your text is now given a rounded appearance using a gray color. The Shapeburst filter is useful as a preprocessor to the Embossing filter, which we shall use next. |
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With the text still selected, choose "Emboss" from the Stylize pullright menu in the Filters menu. |
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The Emboss dialog is displayed, as shown in Figure 8-5. |
Figure 8-5 Emboss Filter Dialog
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Once again you do not need to change the defaults in this dialog, simply press the "OK" button. |
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Your text now has an embossed look. |
Note - Remember that if you apply a filter and then wish to change it, you can select "Undo" from the Edit window and try again.
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Select "Drop shadow" from the Stylize pullright menu in the Filters menu. |
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This displays the drop shadow dialog, shown in Figure 8-6. |
Figure 8-6 Drop Shadow Filter Dialog
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For this filter, you may wish to adjust some of the default settings, Try turning down the "Blur" to make a deeper shadow and turning up the X and Y offsets very slightly to make the text stand away from the shadow a little more. |
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The filter dialog shows you an example of the changes you are making. Sometimes these dialogs are slow in redrawing because of the complexity of the mathematical operations they are performing. Please be patient. |
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When you have selected settings you like, press "OK". |
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Your text now has a drop shadow, making it appear to jump away from the image. Save your image. |
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For the final stage of the tutorial we are going to create and use a gradient. More detailed information on gradients is given in the Gradients section on page 125. |
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In the gradient list window (shown in Figure 8-13) select "New" from the File menu. |
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A new gradient is added showing a black to white gradient. |
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Select the new gradient by clicking over it in the list and then choose "Edit" from the File menu. |
The gradient editor displays two small arrowheads underneath the actual gradient. In order to create a "fading out" effect, we need to set the gradient to range from transparent on the left (to allow the text to show through) to the colour of the background pattern on the right. The applied gradient will then show the text gradually blending in to the background.
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Select the dropper tool from the tool palette. This tool allows you to "pick up" colors from an image. |
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Click over the color in your background pattern at the far right of your image. Figure 8-7 shows you where. |
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This will set the color picked up with the dropper tool to be the foreground color. |
Figure 8-7 Using the Dropper Tool
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Back in the gradient editor, click directly above the arrowhead on the right. |
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This sets the foreground color for that end of the gradient. If this does not happen on the first attempt, keep trying until the appropriate color appears. |
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Back in the Image Editor (with the gradient editor still displayed), click over the foreground color square. |
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This sets it to be transparent and is indicated by a checkerboard pattern. |
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In the gradient editor, click in the color directly above the arrowhead on the left. |
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This sets transparency for the other end of the gradient. |
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From the Type menu in the gradient editor, choose "Circle Up". |
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This should give us the effect we require. Remember that you can experiment with other types by using the "Undo" button in the Edit menu after using the gradient tool. |
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Close the gradient editor. |
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Your new gradient is displayed in the gradient list. |
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Select your new semi-transparent gradient in the gradient list. |
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Select the gradient tool from the tool palette and display its properties dialog again. |
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This time, set the "Use colormap" toggle in the properties dialog and choose "Linear" as the Type. |
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Choose "Select none" from the Selection menu. |
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This is to make sure that subsequent operations affect the whole image. |
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In your image, click halfway down on the far left side and drag a line right across to the right side. |
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Make sure that you have drawn the line right across the whole image. |
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You should now have the effect shown in Figure 8-2 except that in color the effect is much more pronounced and interesting. |
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Now that you have a completed image, you can use it in a Visaj design or you can print it directly from the Image Editor. Choose "Print" from the File menu to do this. |
Open an existing image by selecting "Open..." from the File menu or by pressing the Open button on the toolbar. The image is placed in its own window within the Image Editor.
Selecting "New" from the File menu, or pressing the corresponding toolbar button, displays a dialog prompting you for the size of the new image. You can change the size of it later by selecting "Image Size" from the Image menu. Once you have pressed "Ok" in the Image Size dialog, you are given an empty editing window in the Image Editor.
Because the Image Editor can contain any number of image files, each in its own window, there is a current image. The current image is displayed on top of any others. All operations affect only the current image. The "Close" item in the File menu closes the current image only.
Saving Files
Choose "Save" (or "Save As...") from the File menu or the Save button on the toolbar to write out the current image. Once saved, the image can then be used in Visaj as an object's image property.
The Image Editor can read and write files in JPEG1 and PNG formats and Swing ImageIcons.
Before saving, the Image Editor prompts you for the file type.
View Menu
The items in the View menu affect only how you see the image in the Image Editor. Nothing in this menu changes the saved image. From this menu you can:
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Change the display ratio. 1:1 is the "real size" of the image. |
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Turn the grid on and off. The grid is automatically off for 1:1 or 2:1 displays. |
For all buttons in the Image Editor, tool tips are displayed when the mouse is passed over them. Tool tips do not appear until the pointer has been positioned over a button for one or two seconds.
The status line at the bottom of the Editor displays information on the currently selected tool. Keyboard modifiers are included in this information.
The tool palette on the left of the Image Editor allows you to change between methods of editing. Table 2 lists all the palette buttons along with a brief description of their function.
Palette Tools
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Function
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Pointer Tool. Use this to move the current selection.
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Rectangle Selection Tool. Make rectangular selections with this tool. Holding down the Shift key adds the new selection to any existing selections. Holding down the Control key subtracts the new selection. To select irregular areas, use the Magic Wand tool.
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Panning Tool. With this tool, pan the image left/right and up/down.
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Zoom Tool. Zooms the image in. Holding down the Control key zooms out.
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Ink Dropper Tool. Use this to "pick up" colors in the image. Any color selected with this tool, becomes the foreground color.
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Magic Wand Tool. Click over one pixel with this tool and the selection spreads in each direction until a different color is found. This allows you to select non-rectangular areas. See the Tolerance section on page 120 for information on refining this process. Holding down the Shift key adds to an existing selection, holding down the Control key subtracts from it.
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Fill Tool. Use this tool to flood an area with the foreground color. The area to flood is all pixels with the same color as the one clicked over until a different color in each direction is reached. See the Tolerance section on page 120 for information on refining this process. Hold down the Control key to use the background color.
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Pencil Tool. Colors individual pixels using the foreground color. Hold down the Control key to use the background color.
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Line Tool. Draws lines in the foreground color. Hold down the Control key to use the background color.
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Rectangle Tool. Draws outline rectangles in the foreground color. Holding down the Shift key draws a filled rectangle. Hold down the Control key to use the background color.
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Circle Tool. Draws outline circles in the foreground color. Holding down the Shift key draws a filled circle. Hold down the Control key to use the background color.
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Text Tool. Use this to draw text into your image. Select a start location in the image first. A dialog is displayed for you to enter the text and change the font, size and style before it is added to the image. When added to the image, the text is a "floating" selection - see the Floating Selections section on page 123 for more details,
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Dodge Tool. Use this to lighten parts of your image. Hold down the mouse button and drag across an area to lighten it.
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Burn Tool. Use this to darken parts of your image. Hold down the mouse button and drag across an area to darken it.
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Gradient Tool. Use this to paint gradients into the image. This tool and its properties dialog is described in the Gradient Tool section on page 128.
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Tolerance
You can set the tolerance of the magic wand and fill tools in order to select or fill an area with similar (as opposed to identical) colors. Select "Tool Properties..." from the Edit menu to display the Tolerance dialog. This dialog contains a slider which can be set to any value between 0 and 255. 0 (the default) indicates no tolerance - only exact color matches are selected or filled. A tolerance of 255 will, effectively, match every color. The effect of any setting in this dialog is immediate. This means that you can try different tolerance values easily until you find the one that matches your criteria.
The Image Editor works with a background and a foreground color. These are displayed on the left of the Editor window, as shown in Figure 8-8.
Figure 8-8 Foreground and Background Colors
Setting the Foreground and Background Colors
Any color selected from either the Color chooser or the Color palette, both of which are shown in Figure 8-9, sets the foreground color.
Any of the tools which paint color onto the image use the foreground color. Holding down the Control key forces the Image Editor to use the background color. The background color is used when, for example, a selection is moved, thereby leaving a "hole". The gradient tool and some of the filters also use the current foreground and background colors.
As shown in Figure 8-8, you can switch the background and foreground colors by pressing the double-headed arrow. This is how the background color is set.
A shortcut to change the foreground to black and the background to white is provided. Press the black and white squares, also shown in Figure 8-8.
Transparency
Clicking over the background or foreground color square toggles between that color and transparent. The color square itself becomes transparent with a cross over it. In the image, transparent pixels are drawn with a check pattern. Transparency is useful for images such as toolbar button icons where the color of the toolbar should show through so that they are consistent on different platforms.
Color Chooser and Color Palette (Swatches)
The Color chooser contains two areas. The lower area shows the full color spectrum, or the hue, changing in brightness top to bottom. Selecting in here changes the upper area to display the saturation (left to right) and brightness (top to bottom) of the selected hue.
The Color palette (or Swatches) is a grid of small color squares representing a color cube. The colors of the default swatch are "Web safe"; they are the ones that browsers try to allocate. Keeping to these colors will ensure that your images display well on a Web page. You can, however, load in your own color palettes using the "Load" item in the File menu of the Color palette. Similarly you can save color palettes using the "Save" item.
Figure 8-9 Color Chooser and Palette
You can choose not to display the Color chooser or Color palette window by selecting the appropriate item in the Window menu. Selecting the item again redisplays the window.
Selection is a key feature of the Image Editor. All of the filters and all items in the Image menu affect the currently selected area. Where there is no current selection, the Image Editor assumes that the whole image is selected.
A red line around the selected area indicates a floating selection. A yellow line indicates a non-floating selection.
Floating Selections
Selected areas can be moved around the image and even altered by one of the filters without affecting the image underneath. This is particularly useful for parts of an image such as text which you may need to move around to find a place that is right for it. This ability for selections to move or be altered without affecting the image underneath is referred to as "floating selection". A selected area is automatically floated whenever it is moved by the Pointer tool or if it is passed through a filter which changes its shape (makes it bigger or smaller). There is a "Float Selection" item in the Selection menu but you will not normally need to use this.
Floating selections are automatically dropped back into the image when you select and use a tool from the Tool palette other than the Pointer tool. You can force a selection to drop back into the image by selecting "Drop Selection" from the Selection menu.
If a selection is not floating (it has a yellow line around it) and you move this selection, a "hole" appears in the image where the selection used to be. The hole shows the background color. Once the selection has been moved, it is then floating and can be moved without leaving a "hole". Of course, making "holes" in this way can create an interesting effect.
If you have a floating selection, you can change the way it is painted over the image by selecting the appropriate item from the "Paint modes" pullright menu in the Selection menu. This mode only lasts as long as the current selection. Changing the selection reverts to the default paint mode.
Making a Selection
The Rectangle Selection Tool and the Magic Wand Tool, both shown in Figure 8-10, are available on the Tool palette. They provide two ways of making a selection.
Figure 8-10 Selection Tools from the Tool Palette
As its name suggests, the Rectangle Selection Tool allows you to make rectangular selections. Hold down mouse button 1 and drag a rectangle around the area you wish to select.
The Magic Wand Tool allows you to select non-rectangular areas. Click over one pixel to spread the selection in each direction until a different color is found. This type of selection is suitable for selecting blocks of the same color.
Adding to Selection
Increase the selected area by holding down the Shift key while selecting. This will add the new selection to any already present.
Subtracting From Selection
To subtract areas out of a selection, hold down the Control key while selecting the area to subtract.
Selection Menu
The items in the Selection menu help you to refine and alter your selected area. These items are:
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Select All. Selects the whole image. This is identical to the toolbar button shown in Figure 8-11. |
Figure 8-11 Select All Toolbar Button
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Select None. Deselects the whole image. This is identical to the toolbar button shown in Figure 8-12. |
Figure 8-12 Select None Toolbar Button
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Select Foreground. This item selects all pixels in the image which are the same color as the current foreground. Set the foreground to one of the colors in the image by using the Dropper Tool. See Table 2, "Palette Tools," on page 118. |
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Invert. Changes the current selection to the whole image except the previously selected area. |
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Grow. Increases the selected area one pixel in each direction. |
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Shrink. Decreases the selected area one pixel in each direction. |
The window entitled "Gradients" in the Image Editor shows your list of defined gradients, or colormaps, as shown in Figure 8-13.
Figure 8-13 Gradient List
A gradient is a way of creating color sets. There is always a "start" and an "end" color and the Image Editor makes a smooth transition between the two. You may have any number of subsets, each making a color transition, within one gradient and you may also specify the way in which the color transition is made. All of this is performed in the Gradient Editor which is described below.
The Gradient List appears with a default set of gradients. From the Gradient List's own File menu you can remove a gradient, create a new one or duplicate an existing one, save the list of gradients and load a saved set of colormaps. Place a saved list of gradients into the plugins directory to make the Image Editor load it automatically when it starts up. If you wish to do this, make sure that the list of gradients is saved into a file with a .ser extension. The plugins directory is <VISAJROOT>/lib/plugins, where <VISAJROOT> is the install directory of your Visaj.
Choosing "Edit" from the File menu displays the Gradient Editor, allowing you to edit the currently selected gradient. Click over a gradient in the list to select it. The currently selected gradient is used by the Gradient Tool and by those filters with a "Use Colormap" toggle.
Selecting "Colormaps" from the Window menu hides the Gradient list. Selecting this item again redisplays the window.
Gradient Editor
When you select "New" from the Gradient List's File menu, a new gradient showing one smooth transition from black to white appears in the list. To edit this new gradient, select it and then choose "Edit" from the File menu. The Gradient Editor, shown in Figure 8-14, is displayed.
Figure 8-14 Gradient Editor
In the Gradient Editor, there is a line of color representing the gradient, an area underneath where the gradient can be segmented and a menubar containing two menus at the top.
The segments within a gradient allow you to add more color and color transitions to your gradient. A new gradient contains one segment. To add new segments, select "Split segment" from the Edit menu. To remove segments select "Remove segment" from the Edit menu. To select a segment, select the area between the segment arrows. The operations available from the two menus apply to the currently selected segment. Click in the color directly above a segment arrow to "drop" the foreground color at that point. The Image Editor then makes a smooth transition between the colors of adjacent segment arrows.
The Type menu contains items which affect the way the transition is made between the colors at either end of a segment. There are two sections in this menu. The top section refers to the interpolation type and the lower section to the color type. For the top section, your choices are:
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Constant. This fills the segment with solid color using the color on the left of the segment. Use this with multiple segments to create sharp stripes. |
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Linear. This gives a consistent spread of color change across the segment. |
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3. |
Spline. This applies the color change as a "wave" and therefore makes segments join together more smoothly. |
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4. |
Circle Up and Circle Down. These transformations give a smoother, more rounded effect when used to fill an image. |
For the lower part of the menu, you can choose between the following:
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RGB. This uses RGB values to move from one color to another. |
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2. |
Clockwise Hue and Counter-clockwise Hue. These show the relevant section of a color wheel as defined by the two colors of the segment. You can ask for a clockwise or counter-clockwise journey between the two colors. |
Your edits in the Gradient Editor are not applied until the Gradient Editor is closed.
You may use transparency in gradients to create an interesting effect. If you choose transparent as the color at one end of a gradient, the image appears to gradually "fade" into the background.
Gradient Tool
The gradient tool, available from the Tool Palette, allows you to draw gradients into your image. To use the gradient tool, drag a line in your image along which you wish to paint a gradient. By default this tool uses the foreground and background colors as the start and end points of the gradient. Change this behavior in the properties dialog which is displayed by either double-clicking over the tool or by selecting it and choosing "Tool properties" from the Edit menu. The dialog is shown in Figure 8-15.
Figure 8-15 Gradient Tool Properties Dialog
The "Use Colormap" toggle in the properties dialog tells the Image Editor to use the currently selected gradient from the Gradient List instead of simply using the foreground and background colors. The rest of the properties dialog refers to the way the gradients are drawn. The following are short descriptions of each type of drawing style. By far the best way to understand them, however, is to try them:
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Linear. This draws the gradient straight along the line you drag across the image. |
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2. |
Bilinear. This draws the gradient twice along the dragged line - from one end to the other and then back again. |
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3. |
Radial. This draws outwards in a radial pattern from the start of the dragged line to the end. |
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4. |
Conical. This draws the gradient around the start point with the colors starting from the end point. |
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5. |
Conical Symmetric. This is the same as Conical but drawing the gradient twice - once forward and once backward. |
Use the Shift key when dragging a gradient line to "cycle" the gradient. This causes the gradient to be repeated across the image. The length of the line determines the size of the repeating pattern.
The Edit menu contains items to Cut, Copy, Paste and Clear the current selection. All operations which modify the image can be undone by selecting "Undo" in this menu.
The Image menu contains extra editing functions. These can be divided into the following sub-sections.
Changing the Image Size
There are two operations in the Image menu which directly affect the size of the image:
Crop cuts the image down to the size of the bounding box which contains the selection. If you have a rectangular selection, the cropped image is the same as the selection.
Selecting "Image Size" displays the dialog shown in Figure 8-16. Change the width and height of the image in this dialog.
If you have the "Keep aspect ratio" checkbox selected, the width and height fields are automatically kept to the same ratio.
Figure 8-16 Image Resize Dialog
The Resize dialog allows you some control over what happens when the image is resized. Choose one of the following:
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1. |
Don't rescale image. The image itself stays the same. It is cropped if the new size is smaller and the extra area is filled with background color if the image is made larger. |
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2. |
Replicate pixels. The image is scaled by simple replication. |
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3. |
Average pixels. The image is scaled using an algorithm which produces smoother results than simple replication. Pixels are blended with adjacent pixels to achieve the effect of the same size ratio. |
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4. |
Tile image. The image is repeated to fill the new area. This only applies when an image increases in size. |
Flipping
The image, or the selected part of it, can be flipped across three axes:
Because flipping an image causes its size to change, the Image Editor applies the following rules:
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If there is no selection, the Image Editor assumes that the whole image should be flipped. The image is then resized to display the flipped area.
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If there is any selection (even if this is the whole image), the image is not resized and the selection is left floating after being flipped. See the Floating Selections section on page 123 for information on this.
Flipping the whole image diagonally results in a "blank" area being exposed. This area is left transparent.
Rotating
The whole image or a selected part of it can be rotated through 90º, 180º by selecting the appropriate item or through any other angle by selecting "Rotate..." and typing the angle in the Rotate dialog. The Rotate dialog gives you a preview of the rotated image as you type.
If you are rotating an image which is not square, its size changes. The Image Editor applies the following rules when this happens:
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If there is no selection, the Image Editor assumes that the whole image should be rotated. The image is then resized according to its new shape.
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If there is any selection (even if this is the whole image), the image is not resized and is left floating after being rotated. See the Floating Selections section on page 123 for information on this.
Filling
The "Fill Selection" item in the Image menu floods the selected area with the foreground color. If there is no selection, the whole image is flooded. This item is identical to the toolbar button shown in Figure 8-17.
Figure 8-17 Fill Selection Toolbar Button
Your image, or any selected part of it can be altered by using one of the filters provided in the Filters menu. The filters are divided into pullright sub-menus according to the type of change they effect.
The following applies to all filters:
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1. |
If any part of the image is selected, only that area is filtered. |
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2. |
If there is no selection, the whole image is filtered. |
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4. |
All filters may be undone using "Undo" from the Edit menu. |
Some of the filters need to be customized. If this is the case, a dialog is displayed. A preview of the effect of the filter is provided in this dialog. Most of the items in the Filter menu are pullright menus which group various types of filter. The first two items are commands which are only selectable once a filter has been used. These menu options are described in the following sub-sections. Then follows a brief description of each filter, grouped according to the pullright menu title.
Repeat Last Filter
This item simply repeats the last filter you used. The same settings are used - you are not prompted to change anything.
Show Last Filter
This displays the dialog pertaining to the last filter used, allowing you to change the settings if you wish.
Distort
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1. |
Offset. Moves the image by the X and Y offsets specified in the dialog. The image wraps round. This is useful for creating "seamless" images for tiling into a larger image. |
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2. |
Mesh Warp. Warps an image using a mesh warp algorithm. You supply two warp grids: a source grid and a destination grid. The filter will warp the image so that pixels on source grid points will move to destination grid points. You could produce animations of warping by repeatedly using the warp filter. |
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3. |
Ripple. Produces a rippled effect. The dialog allows you to specify the wavelength and amplitude of the ripple. |
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4. |
Sphere. Applies a fisheye lens type effect to an image. Pixels are displaced according to their distance from the centre of the image. |
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5. |
Twirl. This filter will distort your image by twisting it around the centre. You can change the angle and direction of twist. |
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6. |
Border. Adds a border to the edges of the selected area or the whole image if there is no selection. The resulting image is larger than the original. |
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7. |
Water Ripples. This filter will produce a water ripple effect on your image. You can change the wavelength, phase and amplitude of the ripples and turn antialiasing on or off. |
Colors
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1. |
Transparency. Changes the opacity of the image. Use the dialog to specify how opaque the result should be. |
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2. |
Gamma. Changes the gamma (brightness) of the image. |
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3. |
Gray Out. Grays out the image (or selected part). This is useful for creating the icons to use for insensitive buttons. |
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4. |
Adjust RGB. Alters the RGB (Red, Green, Blue) values of the colors used in the image according to the settings given in the dialog. |
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5. |
Adjust HSB. Alters the HSB (Hue, Saturation, Brightness) values of the colors in the image according to the settings given in the dialog. |
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6. |
Grayscale. Converts the colors in the image to grayscale. |
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7. |
Invert. Changes each color to its complement. |
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8. |
Dither. Dither the colors according to the selected options in the dialog. You can create a dithered black and white image or selects any one of a number of color dithering algorithms. |
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9. |
Diffusion Dither. This filter converts an image to a specified number of colors. You can choose straight or serpentine dithering. |
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10. |
Reduce Colors. Specify the number of red, green and blue colors to use in the image. |
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11. |
Contrast. Allows you to change the contrast and brightness of the image. |
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12. |
Lookup. This filter recolors an image by converting it to a grayscale image and passing it through a color lookup table. |
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13. |
Solarize. Uses a V-shaped transfer curve to convert the colors in the image. |
Stylize
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1. |
Threshold. Changes each color in the image to black or white depending on the specified threshold. Colors below the threshold are coerced into black, those above are forced to be white. |
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2. |
Mosaic. Converts the image into mosaic blocks. Use the dialog to specify the size of the blocks. This effect is often used on TV to hide a person's face. |
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3. |
Add Noise. Changes the color of each pixel by a small random amount which is anything between zero and the number you give in the dialog. Use this to "roughen" a smooth image. |
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4. |
Emboss. Looks at each pixel in the image and calculates the gradient of brightness according to the pixel's location relative to a light source. This results in an "embossed" effect. |
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5. |
Oil. Gives an "oil-painting" effect. This filter can be very slow, especially with large images. |
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6. |
Sparkle. Draws a sparkle or sunburst effect on an image. You can change the number of rays in the sparkle, the randomness of the ray lengths and the radius of the centre of the sparkle. The sparkle is drawn into the centre of the selected area (or the centre of the image if there is no selection). You can use this filter multiple times to create sparkles on corners in images. |
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7. |
Drop Shadow. This filter produces drop shadows for images. It uses the shape of the selection as the shape of the shadow. You can change the offset of the shadow in the X and Y directions and the fuzziness and opacity of the shadow. The output of this filter is an image which is larger than the input by the offsets and the shadow blur radius. |
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8. |
Shapeburst. This filter applies a "shapeburst" gradient to an image. It uses the shape of the selection to determine the shape and then shades from the outside of the shape inwards. You can change the shape of the gradient between linear, circle up, circle down and a smooth transition and you can change the rate at which the gradient changes. By default, the gradient will shade from black at the edges to white in the centre of the shape, but you can also get the filter to invert this. This filter is particularly useful for creating bump maps to enhance the emboss filter. |
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9. |
Marble. creates a marbled effect. Use the dialog to specify the width, height and turbulence to use for the marbling. |
Blur
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1. |
Simple Blur. Blurs the image by the specified amount. |
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2. |
Gaussian Blur. This applies a Gaussian blur to the source image.Blurring images is useful for special effects.You can specify the radius of the Gaussian convolution kernel; the larger the radius, the more blur. This filter can be slow if you specify a large radius. |
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3. |
Sharpen. Gives clearer definition to blocks of color. |
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4. |
Bumps. The opposite of blur, the bumps filter applies an 'embossing' convolution kernel to the image which sharpens edges, producing a bumpy embossed effect. |
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5. |
Motion Blur. Blurs the image in one direction, giving the effect of speed. |
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6. |
Detect Edges. This filter detects edges in an image by applying two Sobel gradient operators and subtracting the results. This produces a 'neon' type effect which can be a good starting point for interesting textures. |
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7. |
Maximum. and Minimum. These filters replace each pixel by the maximum and minimum of the input pixel and its eight neighbors. Each of the RGB channels is considered separately. You can achieve some interesting effects on some images by repeatedly applying these filters. |
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8. |
Median. Applies a color median operator to the image. The output pixel is the median of the input pixel and its eight neighbours.You can use this filter to remove shot noise from an image. This filter may be slow. |
Texture
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1. |
Texture. Create a gray texture using the parameters specified in the dialog. |
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2. |
Weave. This filter simulates woven cloth. You can specify the width of the threads, the gap between them, the pattern of crossings, flat or round threads and whether shading is done at the crossings. You can give the threads constant colours or use the colours from the input image. It can be effective to emboss or use as a bump map the output of this filter. |
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3. |
Checkerboard. Creates checkerboard patterns. You can change the size of the squares in the X and Y directions and the angle at which they are drawn. You can also specify a "fuzziness" for the edges. |
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4. |
Plasma. This filter produces "plasma" clouds using a midpoint displacement algorithm. Random colours are assigned to pixels at the corners of the image and then recursively averaged and displaced to produce pixels at the midpoints. You can specify the turbulence (graininess) of the results and can provide a colormap. This filter can be useful for producing stone-like textures. |
Binary
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1. |
Erode and Dilate. These filters perform binary erosion and dilation, removing or adding black pixels from or to the edges of black areas. You can specify a threshold for the number of neighbors needed to flip pixels. |
|
2. |
Outline. Removes black pixels from the centre of black areas, leaving just the outline. |
|
3. |
Life. Performs one turn of John Conway's game of Life on the image. |
1
The JpegEncoder and its associated classes are Copyright (c) 1998, James R. Weeks and BioElectroMech.
This software is based in part on the work of the Independent JPEG Group.
Copyright
© 1998, 1999 Pacific Imperial Inc.,
TakeFive Software Inc.
All Rights Reserved.