THE GIMP Bible PHẦN 8 pdf

Part IV: Exploring Filters and Effects FIGURE 16-24 Use the Round Corners filter to round off the corners on your image. Within the Round Corners filter dialog, you can adjust the Edge Radius option. This option allows you to set (with the input box) a radius setting, where the rounding of corners will origi- nate from. You can add a drop shadow to your image by checking the Add Drop-Shadow check box. You can then adjust the X and Y Offsets for that shadow and use a Blur Radius option to define the shadow’s softness. Slide Old film footage and slide-like film are created (or emulated) by the Slide filter within GIMP’s myriad filter options. This one is extremely handy if you are looking for the ‘‘old film’’ effect. This is a simplified version of the Filmstrip filter (Filters  Combine  Filmstrip) covered in Chapter 15. This filter is located in the image window menu under the Filters  Decor menu. Run it by going to Filters  Decor  Slide. Figure 16-25 shows the Slide filter dialog. You have a few things t o consider when using this filter. For one, it encases the original image into a slide. Because of the size restrictions, your image may be cropped to fit. Second, this filter (script) works only on specific image types. F or example, only RGB and grayscale images that contain one layer will work. Third, you should consider using the Work on Copy check box selection. By doing so, you can protect the original image and create a slide out of a new one. 494 Chapter 16: Enhancing Images with Artistic Filters FIGURE 16-25 Using the Script-Fu: Slide filter to create images that look as if they are part of a film reel Other options to configure include the following:  Text — Once you apply the filter, the slide created can be tagged by a name. If you add a description within the Text section of the dialog, you can mark your slide with a title (for example).  Number — Just like true film footage, the segments run in numerical order. You can add a number here to denote where this slide fits into a group of multiple slides.  Font — You can select and adjust the different font options that appear within the text and numbering of your slide.  Font Color — You can also adjust what color scheme your font selection adheres to. If you choose orange, all of the text and numbering in your slide are colored as such. Stencil Carve The Stencil Carve filter creates a carving effect on your image. The carving effect is basically performing edge detection on your image and using that to attempt to generate silhouettes that could be cut from the image. The carving effect is applied to a carve layer. Therefore, you must use a second layer when applying this filter. If you do not have a multilayer setup, this option appears grayed out. If you do not have a second layer configured, you can create a new one easily. The simplest way to do this is to create a new image by going to File  New. 495 Part IV: Exploring Filters and Effects This prompts the Create a New Image Wizard and a new dialog appears. Create a carve layer by specifying the size and dimensions of the secondary image (the image you want to affect). Click OK to create the new layer, also called the source. Then, load in the image you want to carve, which will be the target — the image you will carve. Thereareafewrulesyoumustfollow.Thesourceimagemustbeagrayscaleimageanditmust be a single-layer alpha channel. The image you want to affect (carve), needs to be a single-layer RGB or grayscale image. The image layers must also be the same size. This filter is located in the image window menu under the Filters  Decor menu. Run it by going to Filters  Decor  Stencil Carve. Figure 16-26 shows the Stencil Carve filter dialog. FIGURE 16-26 Running the Stencil Carve filter on an image with the Carve White Areas selection applied. Here the Stencil Carve filter shows the outline and image of a black cat To load the target, select Image to Carve and browse to the image you want to edit. If you did not load an image into the image window, you will not find your image listed in the drop-down list. You can select the Carve White Areas option by selecting the check box to apply one of two effects:  Carve White Areas (enabled) — A stencil must be selected to carve with. If this option is selected, the source (background) layer is used as the stencil.  Carve White Areas (disabled) — A secondary stencil can be selected. If you uncheck this option, the source images colors are inverted. This is then used as the stencil to carve with. Stencil Chrome The Stencil Chrome filter (Filters  Decor  Stencil Chrome) creates a chroming effect on your image. It is very similar to the Stencil Carve filter. It is nearly identical in operation as well. All of the same rules apply, but the effect is completely different as it produces a chrome look instead. 496 Chapter 16: Enhancing Images with Artistic Filters Figure 16-27 shows the Settings tab options within the Stencil Chrome filter dialog. FIGURE 16-27 Using the Stencil Chrome filter within GIMP, you can apply chroming effects to your images based on specific settings to saturation, lightness, and coloring. You can run the Stencil Chrome filter and configure multiple options:  Chrome Saturation — When the slider or input boxes are adjusted, the level (or amount) of saturation is increased or decreased to apply more or less chroming effect to your image.  Chrome Lightness — When the slider or input boxes are adjusted, the level (or amount) of lightness is increased or decreased to apply more or less lighting effect to your image.  Chrome Factor — When the slider or input boxes are adjusted, the level (or amount) of chrome applied is increased or decreased to apply more or less overall chroming effect to your image.  Environment Map — When the drop-down list is selected, you can choose an image (environmental map) that will supply the chroming effect.  Highlight Balance — You can click the color bar to select the highlight color to be used.  Chrome Balance — You can click the color bar to select the chrome color balance to be used.  Chrome White Areas — When this check box is selected, the white areas in your image will be chromed, as opposed to the darker areas in your image. Note You can download chroming effects at the GIMP Plugin Registry. As mentioned in other chapters, one of the nice things about GIMP is that you can expand it using additional scripts and plug-ins. For example, you 497 Part IV: Exploring Filters and Effects can download Chromonium (http://registry.gimp.org/taxonomy/term/315), which is a script that applies chroming effects to your work easily once installed. More on plug-ins and the GIMP Plugin Registry can be found in Chapter 21.  Summary This chapter has covered the use of many GIMP filters, including those found within the Artistic and Decor filter menus. Each set of filters provides quite a few means of enhancing your image, from lighting effects to blurring to distorting and chroming. The next chapter covers the use of specialized filters. These filters include web filters, animation filters, photo filters, as well as other layer effects and Alpha to Logo. We cover how to use filters to speed up web design as well as how to work with filters to aid animation. The chapter also looks at the art of creating quick ‘n’ dirty logos. You learn how to work with layer effects as well as how to use filters to simplify photo editing in multiple ways. All of this up next! 498 Working with Specialized Filters IN THIS CHAPTER Using filters to speed up web design Working with filters to aid animation Creating quick ‘n’ dirty logos Understanding layer effects S pecialized filters are u seful when you want to apply your work to the web. The Internet and the servers that provide the pages you view host your art. To get the best possible view of your work, and fast load times, you can apply GIMP’s Specialized filter set. For example, Web filters in GIMP optimize the size, functionality and appearance of an image for use on for the web. Web Filters These filters are mostly used on images used for web sites with t ables, as well as for quicker loading of pages, hyperlinking and so on. The filters themselves work with your image to make them ‘‘web-ready’’. The Image Map filter is used to add linkable hot-spots on your digital image. Often called ‘‘slicing’’, this function will take an image too large for the screen and break it up into smaller segments in order to load faster. It is also used to apply hyperlinks to specific sections of the image. This is done through HTML table code. You can also use the Semi-Flatten filter, which is used for images without an alpha channel and can create semi-transparent images. You can use web filters for most of your slicing and dicing needs. The Slice filter is helpful when you want to create tables in HTML for your sliced work. Image Map When looking to create a hyperlink from an image source, you can use the Image Map filter. This filter is used to create a link from an entire image, or with the grid, you can select a single portion of your image to be linkable. When you hover your mouse pointer over the final image, you will be able to open a new page, file, or other component you decide to link up to it. 499 Part IV: Exploring Filters and Effects You should t ake note that because this filter is extremely hardware resource intensive (particu- larly the CPU), it may be difficult to use the filter as the preview may take up to a minute to refresh based on your adjustments. If running GIMP on a system with few resources, using the Image Map filter may take some time and lead to some frustration on the artist’s part. This filter is found in the image window menu under the Filters  Web menu. Run it by going to Filters  Web  Image Map. Figure 17-1 shows the image map found within the Image Map filter dialog box. FIGURE 17-1 Using the Image Map filter to specify linkable sections of your graphic, which, when clicked, will select a hyperlinked web site, file, or other component you choose The Image Map filter can be confusing to use at first because you have to select to use the grid from the m enu options, as well as use the toolbar on the top-left side of the filter’s dialog box. Here you can make selections based on your grid elements. Once you make your selection, you can open the Area Settings dialog. To do this, use the right-hand side section/pane of the dialog box and double-click on the active selection within the pane. You can now make adjustments on the Link, Rectangle, and JavaScript tabs. Each tab offers many options for you to select when defining a selection on your m ap. The Link tab is useful for selecting the link type. In this section you can choose from many options to include: Web Site, File, FTP Site, WAIS, Gopher, Telnet, and e-mail, as well as Other, which you can specify manually. 500 Chapter 17: Working with Specialized Filters You can also select the URL to activate when your selection is clicked (or selected). You can type in the target location, or specify via the file/folder Browse button. Once you select your URL, you can choose how it will interact with the site when clicked on. For example, you can specify that the target be a new window, so that when your image is clicked on, a new web browser will open with the URL you wanted to use. On the Rectangle tab, you can choose the dimensions manually — this way you can adjust your selection based on exact height, width, and X and Y settings of your choosing. The JavaScript tab is helpful when you want to create the most commonly used JavaScript commands, such as onMouseover, onMouseout, onFocus, and onBlur. Semi-Flatten The Semi-Flatten filter effect is helpful when you are attempting to create a background color blend with your foreground image selection. For example, if you have a web page with green or red coloring, you can blend some of those coloring aspects into the image when you flatten it. Not to be confused the with Layer dialog box Flatten command, which fully flattens all layers to one, this will simply merge (or blend) the coloring together to create a visual effect for t he viewer of the page (or image). This filter is found in the image window menu under the Filters  Web menu. Run it by going to Filters  Web  Semi-Flatten. Figure 17-2 shows the flattening of the background image with the foreground image, found within the Semi-Flatten filter dialog box. It is available if your image holds an Alpha channel. Otherwise, it is grayed out. If your image does not have an Alpha channel, you can create one (or associate one) within the Layers dialog box. You can also adjust your color schemes (for background and foreground layers) in GIMP’s toolbox; click on the color section and adjust the coloring as you would like to see it. Image Slice The Image Slice filter is similar in function to the Image Map filter, except it creates only the actual slices that you can then work on within the Image Map filter (as an example). Here, you can create exact slices based on the original dimensions of the image you want to edit. This filter is found in the image window menu under the Filters  Web menu. Run it by going to Filters  Web  Slice. If you find that you do not have this option available, then you need to download and install the Image Slice ( http://registry.gimp.org/node/14953) plug-in from the GIMP registry. Figure 17-3 shows the Script-Fu: Image Slice filter dialog box where you can make adjustments t o the rows and columns you will slice. You will be able to use this filter only if your image holds an Alpha channel. Otherwise, it is grayed out. Tip If you slice up your work, you can do the opposite and join the slices to create a single image from multiple ones. How? Well, in Figure 17-4, you can see the File Selection dialog box from within the Image Slice dialog. You can load these so that you can then create a single image. Figure 17-5 shows how GIMP will create multiple layers for each image slice. This way, you can adjust each slice per layer as you need to.  501 Part IV: Exploring Filters and Effects FIGURE 17-2 Using the Semi-Flatten filter effect to blend background colors into foreground images. In this figure, the background was black. Black is then added to portions of your image when duplicating the background image color. FIGURE 17-3 Using Script-Fu: Image Slice to create multiple chunks out of a single image. It does this by slicing along the Rows and Columns adjustments you select and then saves it where you specify, as the file type you want. 502 Chapter 17: Working with Specialized Filters FIGURE 17-4 Using Script-Fu: Image Slice to create multiple chunks out of a single image. It does this by creating files out of each slice you create. FIGURE 17-5 When viewing the Layers dialog box, you can see how each slice is created as a single layer for easy editing. 503 [...]... operations to it To do this, click the Add button at the bottom of the Filtermacro window When you click this button, GIMP gives you a Filtercall Browser window like the one in Figure 18- 14 This window lists the filters you’ve used in the current GIMP session in the list on the left Click any of these filters and the panel on the left displays some helpful information on what the filter does and what sort of... Figure 18- 3 shows, the only control for this operation is a radius for the blur, measured in pixels The type of blur that’s used for this operation is actually GIMP s Gaussian Blur, using the IIR method This is the same as opening each of your images and choosing Filters Blur Gaussian Blur and then enabling the IIR radio button under the Blur Method label FIGURE 18- 3 The Blur tab in DBP Using the Colour... Processing Multiple Files So you want to perform the same operation on a whole bunch of images They may or may not all be in the same folder, but you know you want to perform the same actions on all of them This is the essence of batch processing; the files you want to work on are the batch and the actions you want to perform are the processing GIMP offers you the ability to do this by hand 513 IN THIS CHAPTER... processed Figure 18- 9 shows the settings for this tab and the following list explains what each one does 520 Chapter 18: Batch Processing with Automating Filters FIGURE 18- 7 The Crop tab in DBP FIGURE 18- 8 The Sharpen tab in DBP 521 Part IV: Exploring Filters and Effects To Directory — This controls where the processor saves files By default, your images are saved in exactly the same folder they came from... that, click the Select Dir button and choose the folder you want to use from the File Chooser that appears If you decide that you would instead rather use the default setting, just click the Source Dir button As you make these changes, the values next to the Original and Becomes labels change to reflect the modifications you’ve made Prefix/Add Postfix — If you’re saving these images back to their source... 90◦ to the right Anti-Clockwise — Rotates your image 90◦ to the left, or counter-clockwise Upside-Down — Rotates your image 180 ◦ FIGURE 18- 2 The Turn tab on the DBP plug-in Use the drop-down menu to select the type of rotation you want Once you do that, you can either click Start or move on to the next operation you want DBP to perform Note If you’re in the U.S., you may notice that some of the terminology... installation of GIMP They’re provided by plug-ins, or programmed extensions to GIMP Chapter 21 covers plug-ins in a more thorough manner, including where to find plug-ins and how to install them As I go through this chapter, I’ll indicate which plug-in provides the feature I’m covering From there, you can either track them down online or download them directly from this book’s companion web site at www.gimpbible.com... what you set and the height is proportionally calculated to a value larger than the height setting you entered Figure 18- 6 illustrates the differences between each of the Fit settings FIGURE 18- 5 The Resize tab in DBP 519 Part IV: Exploring Filters and Effects FIGURE 18- 6 On the far left is a rectangle that represents the original image dimensions From left to right are how each of the Fit settings... found in the image window menu under the Filters Animation menu Run it by going to Filters Animation Rippling Figure 17 -8 shows the Rippling filter dialog box In the Script-Fu: Rippling effect dialog box, you can adjust the rippling strength (which is self-explanatory), the number of frames, and the edge behavior The Rippling Strength slider and input box options allow you to adjust the strength of the ripple... include in the batch, you can select those images from the list of files under the Input tab using the same selection shortcuts mentioned previously and then click the Remove Files button If you decide that you foolishly chose the entirely wrong set of images, click the Clear List button After you choose your images, you can begin to choose the operations you want to perform on them Each of the tabs in . to perform the same actions on all of them. This is the essence of batch pro- cessing; the files you want to work on are the batch and the actions you want to perform are the processing. GIMP offers. layer by specifying the size and dimensions of the secondary image (the image you want to affect). Click OK to create the new layer, also called the source. Then, load in the image you want to. your work to the web. The Internet and the servers that provide the pages you view host your art. To get the best possible view of your work, and fast load times, you can apply GIMP s Specialized