THE GIMP Bible PHẦN 1 pdf

Whether you’re a hobbyistinterested in a free image editor, or a seasoned professional curious about what ‘‘that GIMP thing’’ is capable of, this book is designed to meet your needs and

GIMP Bible

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To my mother, who once made the mistake of telling me I could do anything I set my mind to do only to have me terrorize her by trying to do everything.

— Jason van Gumster This book is dedicated to my son, Dylan James.

— Robert Shimonski

About the Authors

Jason van Gumster got into animation when he realized that he wanted to create movies

but that actors are generally intolerant of having pianos dropped on them Using open sourcetools at nearly every step in production, Jason has produced animations and visual effects fortelevision, film, and video games in his official capacity as a ‘‘Production Monkey’’ for HandTurkey Studios, the company he helped start in 2005 He uses GIMP and the GIMP Anima-tion Package on a daily basis for a variety of tasks ranging from creating graphics for the Weband television to drawing storyboards and creating images for both 3D and hand-drawn anima-

tions Also the author of Blender for Dummies, Jason has given numerous live workshops and

demonstrations on Blender internationally Combining a unique educational background in mation and computer engineering with a penchant for the ridiculous, he strives to refine boththe technical and creative aspects of production by taking on (and successfully completing) crazyprojects like producing a 5-minute 3D animated short in a mere 48 hours with an internationalteam communicating via the Internet Based in Richmond, Virginia, Jason can often be found incaf´es and diners drawing, espousing the virtues of open source software, or catching confusedlooks from strangers as he contorts his body to better visualize a scene he’s animating

ani-Robert J Shimonski is an expert digital media and technology consultant living in New York.Rob is also an author, and a regular contributor of tutorials and articles on digital editing, pro-duction, and development

Having spent the past decade working with large, medium, and small companies as a cal consultant, Rob has helped develop digital art packages for many professional clients andbusinesses

techni-Rob has been working with GIMP for many years and has created graphics for corporate websites, TV commercials, and professional magazines Having worked with the many open sourcetools, Rob relies on GIMP for most of his graphics work

Rob can be found online atwww.shimonski.com

About the Technical Editor

John Karnay is a published author and editor with over a dozen works to his credit He hasbeen writing and editing in the fields of technology, fiction, comic books, computer software,music, and video games for over 15 years John is a computer software, audio engineering,graphic design, networking and IT specialist who has been working with and deployingMicrosoft-, Apple-, and open source-based technologies for over 15 years He also specializes inSpanish-to-English translation John currently works in the video game industry as a producer,content writer and quality assurance manager and has over 30 game titles to his credit

John resides in Jackson Heights, New York and spends his free time with his daughter Auroraand with his loving wife and partner, illustrator Gloria Rios

Mary Beth Wakefield

Associate Director of Marketing

First (and most important) thanks go to the surprisingly small group of dedicated

develop-ers who voluntarily spend their free time coding GIMP Most people don’t realize that aprogram of GIMP’s complexity is updated and maintained by only a handful of develop-ers whose primary motivation is the fact that they enjoy doing it Your patience and help with

my questions and misplaced bug reports are sincerely appreciated You are not and cannot bethanked enough

Thanks, also, to the entire team at Wiley Were it not for this talented group of professionals(and large quantities of coffee), this book would never have been produced I’d especially like

to acknowledge my project editor of unparalleled patience and tireless energy, Sydney Jones I’dalso like to thank Rob Shimonski not only for working as this book’s initial technical editor, butalso for stepping up and agreeing to write a portion of the book on incredibly short notice Ithas been a pleasure to work with both of you — Jason van Gumster

A book takes a lot of work to create and requires a very large team effort I would like to thankthe Wiley production team for all of their hard work I would first like to thank my co-authorJason, who is truly a GIMP wizard Special thanks goes out to Sydney for her untiring dedi-cation to this project I would also like to thank technical editor Johnny for keeping things ontrack Lastly, I would like to thank Carol, who got me started on the project and kept everythinglocked on — Robert Shimonski

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Introduction xxxi

Part I: Meet GIMP 1

Chapter 1: What Is GIMP? 3

Chapter 2: Thinking Digitally 41

Part II: Getting Started 59

Chapter 3: Working with Files 61

Chapter 4: A Brief Overview of GIMP’s Tools 93

Chapter 5: Taking Advantage of Paths 109

Chapter 6: Working with Layers and Masks 135

Chapter 7: Using Channels 171

Part III: Manipulating Images 185

Chapter 8: Transforming Images 187

Chapter 9: Adjusting Colors 221

Chapter 10: Working with Text 281

Chapter 11: Painting in GIMP 297

Chapter 12: Enhancing Photos 323

Part IV: Exploring Filters and Effects 347

Chapter 13: Implementing Blur, Enhancement, and Distortion Filters 349

Chapter 14: Using Image Creation Filters 391

Chapter 15: Using Compositing Filters 427

Chapter 16: Enhancing Images with Artistic Filters 475

Chapter 17: Working with Specialized Filters 499

Chapter 18: Batch Processing with Automating Filters 513

Chapter 19: Using GIMP Animation Package 537

Chapter 20: Working with Video-Specific Functions in GIMP 567

Part V: Advanced Topics 599

Chapter 21: Finding and Installing Plug-ins 601

Chapter 22: Creating Custom Effects with Scripting 629

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Part VI: Appendices 647

Appendix A: Downloading and Installing GIMP 649

Appendix B: Setting Up External Input Devices 663

Appendix C: Customizing GIMP 679

Appendix D: Additional Resources 691

Appendix E: What’s on the Web Site 695

Index 697

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Introduction xxxi

Part I: Meet GIMP 1 Chapter 1: What Is GIMP? 3

Knowing What GIMP Can and Cannot Do 6

Working with GIMP’s Interface 7

Windows and Menus 7

Docks and Dialogs 9

Images and Canvases 16

Parts of the Image Window 16

The Concept of a ‘‘Canvas’’ 18

Setting Preferences 21

The Module Manager 21

GIMP Preferences 22

Customizing Keyboard Shortcuts 37

Summary 39

Chapter 2: Thinking Digitally 41

Digital Images vs Traditional Photographs 41

Raster Graphics vs Vector Graphics 44

Raster Images 44

Vector Images 44

Resolution and Image Size 46

Changing Image Size and Resolution 47

Confusing Terminology 49

Color Depth 50

Color Spaces and Color Modes 51

Color Spaces 51

Color Modes 52

Compression 55

Lossless Compression 55

Lossy Compression 57

Summary 58

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Part II: Getting Started 59

Chapter 3: Working with Files 61

Opening Files 61

Opening Images 62

FileOpen 62

Other Ways to Open an Image 66

Creating a Blank New Image 68

Generating an Image from Plug-in or Hardware 69

Creating an Image from a Screenshot 70

Creating an Image from a CMYK TIFF 72

Using a Scanner to Import a Drawing or Photograph 73

Letting GIMP’s Automated Scripts Generate an Image 74

Managing Open Images 75

Working in the Image Window 77

Copying and Pasting 79

Fun Things You Can Do with Paste (Besides Eat It) 79

Advanced Copy and Paste with Buffers 81

Taking Advantage of Undo 82

Saving Files 84

GIMP’s Native Format: XCF 85

Other Formats 86

Summary 90

Chapter 4: A Brief Overview of GIMP’s Tools 93

The View Menu 93

Modifying Your View in the Image Window 93

Using Display Filters to Color Correct GIMP to Your Monitor 96

Showing and Hiding Information 97

Snapping Controls 98

Padding Color 98

Showing and Hiding Parts of the Image Window 99

Selection Tools 99

Rectangle Select 100

Ellipse Select 101

Free (Lasso) Select 102

Fuzzy Select 102

Select by Color 103

Intelligent Scissors Select 103

Foreground Select 103

Image Tools 104

Informational Tools 104

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Color Picker 104

Zoom 105

Measure 105

Transform Tools 106

Paint Tools 106

Color Tools 106

Summary 107

Chapter 5: Taking Advantage of Paths 109

The Advantages of Paths: Get Some Vector in Your Raster 109

Creating Paths 110

Drawing with the Paths tool 111

Creating a Path from a Selection 114

Managing Paths 118

The Paths Dialog 119

Importing and Exporting Paths 121

Importing Paths 121

Exporting Paths 123

Using Paths 123

Painting along a Path 124

Stroke Line 125

Stroke with a Paint Tool 126

Practical Example: Faking an Ink Drawing 129

Selecting with a Path 132

Summary 133

Chapter 6: Working with Layers and Masks 135

Managing Layers 136

A Quick Overview of the Layers Dialog 136

Adding, Duplicating, and Removing Layers 139

Creating a New Layer 140

Duplicating an Existing Layer 141

Deleting Layers 142

Arranging Layers in the Stack 142

Grouping and Merging Layers 143

Merging Layers 143

Grouping Layers 144

Manipulating Layers 146

Resizing Layers 146

Modifying the Layer Boundary Size 146

Scaling Layers 147

Offsetting the Content of a Layer 148

Aligning Layers 149

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Working with Layer Transparency 152Additional Layer Transparency Features 152Using Layer Transparency for Selections 154Blending Modes 156Using Layer Masks 162Defining Layer Masks 162Modifying Layer Masks 163Effectively Using Features in the Select Menu 165Summary 169

Chapter 7: Using Channels 171

Understanding Channels 171Red, Green, and Blue: The Default Color Channels 172

A Fistful of Awesome: The Alpha Channel 173Using Channels 175Creating Channels 176Taking Advantage of Channels Once They’re Created 177Practical Application: Changing the Background 179Summary 183

Part III: Manipulating Images 185

Chapter 8: Transforming Images 187

Adjustments Available in the Image and Layer Menus 187Sizing 188Fit Canvas to Layers 188Layer to Image Size 189Cropping and Guillotine 190Crop to Selection 191Autocrop 191Zealous Crop 193Guillotine 194Flipping and Rotating 195Flipping 195Rotating 196Liquid Rescale: Quite Possibly the Coolest Thing Ever 198Using Liquid Rescale 199Output Options 202Advanced Options 204Interactive Mode 206Advanced Techniques: Smart Zoom 208Using the Image Tools 209Alignment Tool 209Crop Tool 213

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Transformation Tool 215Moving 217Rotating 218Scaling 218Shearing 218Changing Perspective 218Flip Tool 219Summary 220

Chapter 9: Adjusting Colors 221

Using the Color Menu 223Working with the Color Tools 223Features Available for All Color Tools 224Color Balance 226Hue-Saturation 227Colorize 229Brightness-Contrast 230Threshold 231Levels 232Curves 236Posterize 239Desaturate 241Inverting Values 243Using Automated Adjustments 243Equalize 244White Balance 245Color Enhance 245Normalize 246Stretch Contrast 247Stretch HSV 248Working with Separated Color Components 249Channel Mixer 249Composing, Decomposing, and Recomposing 252Remapping Colors 255Rearranging and Defining a Color Map 256Alien Map 257Color Exchange 258Gradient Map 260Palette Map 260Rotate Colors 260Sample Colorize 263

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Analyzing Your Colors with Info Tools 266Histogram 266Border Average 267Colorcube Analysis 267Smooth Palette 268Color Filter Plug-ins 269Color to Alpha 269Colorify 269Filter Pack 269Hot 272Maximum RGB 272Retinex 273Exporting Color Separations with the Separate+ Plug-in 275Summary 279

Chapter 10: Working with Text 281

Uses for Text in Images 281Adding and Editing Text 282Customizing Text from the Text Panel 286Font and Size 286Font Edging 287Changing Text Color 288Justification, Indentation, and Spacing 289Making Text Go Along a Path 290Using Text to Create a Path 292Working with Text Layers 294Summary 296

Chapter 11: Painting in GIMP 297

Working with Brushes 298Adjusting Brushes 299Using Tool Options to Adjust Brushes 299Quickly Adjusting Brush Settings from the Image Window 302Creating New Brushes 303Using the Brush Editor to Create Procedural Brushes 305Creating Animated and Bitmap Brushes 307Paint Dynamics and Using Brushes with a Drawing Tablet 313GIMP Paint Studio — A Painter-Friendly Batch of Presets 314Drawing Calligraphic Lines with the Ink Tool 315Working with Gradients 317Creating Pattern Fills 320Summary 321

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Chapter 12: Enhancing Photos 323

Traditional Photographer Tools 323Blur/Sharpen 324Smudge 326Dodge/Burn 329Using Cloning and Healing to Fix Problem Areas 331Clone Tool 331Perspective Clone Tool 335Healing Tool 338Using the Exposure Blend Plug-in 341Summary 345

Part IV: Exploring Filters and Effects 347

Chapter 13: Implementing Blur, Enhancement, and Distortion

Filters 349

Common Features among Filters 350Using the Blur Filters 353Blur 353Gaussian Blur 353Motion Blur 354Pixelize 357Selective Gaussian Blur 359Tileable Blur 359Enhance Filters 360Antialias 361Deinterlace 361Despeckle 362Destripe 363

NL Filter 364Red Eye Removal 365Sharpen 365Unsharp Mask 367Distortion Filters 368Blinds 368Curve Bend 369Emboss 371Engrave 372Erase Every Other Row 374IWarp 374Lens Distortion 377Mosaic 378Newsprint 380

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Pagecurl 381Polar Coordinates 382Ripple 383Shift 384Value Propagate 384Video 386Waves 386Whirl and Pinch 388Wind 389Summary 390

Chapter 14: Using Image Creation Filters 391

Light and Shadow Filters 391Gradient Flare 392Lens Flare 395Lighting Effects 397Sparkle 400Supernova 402Drop Shadow 402Perspective 404Xach-Effect 404Lens Effect 405Glass Tile 405Noise Filters 406Scatter HSV 406Hurl 407Random Pick 407RGB Noise 408Slur 409Spread 409Render Filters 411Clouds 411Difference Clouds 411Plasma 412Solid Noise 412Nature 413Flame 413IFS Fractal 414Pattern 414CML Explorer 415Checkerboard 415Diffraction Patterns 416Grid 416Jigsaw 418

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Maze 418Qbist 420Sinus 420Circuit 420Fractal Explorer 421Gfig 421Lava 422Line Nova 422Sphere Designer 423Spyrogimp 424Summary 425

Chapter 15: Using Compositing Filters 427

Working with Edge-Detect Filters 427The Difference of Gaussians Option 430Edge 431Laplace 434Neon 435Sobel 436Using the Filters in the Generic Menu 438Convolution Matrix 438Dilate and Erode 442Using the Combine Filters 443Depth Merge 443Filmstrip 446Selection 447Advanced 449Taking Advantage of Mapping Filters 450Bump Map 450Displace 453Fractal Trace 456Illusion 457Make Seamless 459The Map Object Filter 459Options 460Light and Material 461Orientation 462Extra Tabs: Box and Cylinder 463Paper Tile 464Small Tiles 466Tile 467Warp 468Basic Options 469Advanced Options 471

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More Advanced Options 471Using Warp to Map a Logo to a Photo of Rumpled Cloth 472Summary 473

Chapter 16: Enhancing Images with Artistic Filters 475

Artistic Filters 475Apply Canvas 475Cartoon 476Cubism 477GIMPressionist 479Oilify 480Photocopy 480Predator 482Softglow 484Van Gogh (LIC) 486Decor Filters 487Add Bevel 487Add Border 488Coffee Stain 489Fuzzy Border 491Old Photo 492Round Corners 493Slide 494Stencil Carve 495Stencil Chrome 496Summary 498

Chapter 17: Working with Specialized Filters 499

Web Filters 499Image Map 499Semi-Flatten 501Image Slice 501Animation Filters 504Blend 504Rippling 505Spinning Globe 506Waves 507Optimizing Filters 508Alpha to Logo 5083D Outline 508Summary 511

Chapter 18: Batch Processing with Automating Filters 513

Batch Processing Multiple Files 513Using the Batch Process Plug-in 514Using the Input Tab to Select Images 515

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Using the Turn Tab 516Using the Blur Tab 517Using the Colour Tab 517Using the Resize Tab 518Using the Crop Tab 520Using the Sharpen Tab 520Using the Rename Tab 520Using the Output Tab 522Using the Contact Sheet Plug-in 524Automating Tasks with GAP’s Filtermacro 527The Filtermacro Window 527Adding Operations 528Filter All Layers 530Using Filter All Layers 531Apply Constant 532Apply Varying 533

A Quick Shortcut: Selection to AnimImage 535Summary 536

Chapter 19: Using GIMP Animation Package 537

Using Still Image Sequences and Layers for Animation 538Creating a Simple GIF Animation with Layers 538Images to Layers and Layers to Images 542Splitting a Layer Image into an Image Sequence 542Converting an Image Sequence into a Single Layered Image 544Managing the Frames of Your Image Sequence with GAP 546The Easy Way: GAP’s Video Navigator 546Additional Frame Management Functions in the Video Menu 549Convenience Features to Improve Workflow 553Working with the Move Path Feature 553Morphing 556Onionskinning 559Creating a Storyboard 562Summary 566

Chapter 20: Working with Video-Specific Functions in GIMP 567

Playing Back Video 568Video Options 568Audio Options 572Preferences 574Encoding Video 575Setting Video Options 576Setting FFMPEG Parameters 578Setting AVI1 parameters 583

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Setting Audio Options 586Configuring the Audio Tool 588Using the Extras Tab 590The Encoding Tab 592Extracting Frames from a Video File 592Using Extract Videorange 593Setting Input Options 593Setting Output Options 595Using MPlayer-Based Extraction 596Summary 598

Part V: Advanced Topics 599

Chapter 21: Finding and Installing Plug-ins 601

The GIMP Plugin Registry 602Installing Plug-ins 604Installing Scripts 605Installing Compiled Plug-Ins 606

A Few Plug-ins Worth Mentioning 608Exposure Blend 608GIMP-GAP 609Installing GAP on Linux 610Installing GAP on Mac OS X 612Installing GAP on Windows 612GIMPshop and GimPhoto/GimPad 613GIMPshop 613GimPhoto/GimPad 614GREYCstoration and G’MIC 615Layer Effects 617Liquid Rescale 621Installing Liquid Rescale on Linux 621Installing Liquid Rescale on Mac OS X 623Installing Liquid Rescale on Windows 623Separate+ 623Installing Separate+ on Linux 624Installing Separate+ on Mac OS X 626Installing Separate+ on Windows 626Summary 628

Chapter 22: Creating Custom Effects with Scripting 629

Multi-Lingual GIMP: Scripting Languages GIMP Understands 630Scheme and Python — GIMP’s Primary Scripting Languages 631

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Other Scripting Languages Supported by GIMP 633Taking Advantage of the Procedure Browser 634Using the Scripting Console 634Writing a Custom Script for GIMP 635Building a Structure for Your Script 636Writing the Meat of Your Script 639Summary 645

Appendix A: Downloading and Installing GIMP 649

Installing GIMP on Linux 649Debian/Ubuntu 650Fedora 652OpenSUSE 653Gentoo 655Mandriva 655Installing GIMP on Windows 656Regular Installation on Windows 657Installing GIMP Portable 658Installing GIMP on Apple Macintosh 660Installing GIMP on OS X 661Installing GIMP from MacPorts 662

Appendix B: Setting Up External Input Devices 663

Acquiring Images with a Scanner 663Linux 664Mac OS X and Windows 666Printing Images 668Using the Bundled GTKPrint Module 668Printing with Gutenprint 671Installing Gutenprint 671Using Gutenprint 672Configuring a Drawing Tablet 676

Appendix C: Customizing GIMP 679

Changing the Splash Image 679Using a Different Theme 681Linux 682Windows 684Mac OS X 687Fixing the ‘‘Yellow Cursor’’ Bug 687Changing Your GTK+ Theme 688

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Appendix D: Additional Resources 691

On the Web 691Internet Relay Chat 694

Appendix E: What’s on the Web Site 695

How the Site Is Organized 695Getting the Most out of the Site 696

Index 697

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Thanks for picking up GIMP Bible, which I hope is the most comprehensive and

up-to-date book on this very cool piece of Free Software Whether you’re a hobbyistinterested in a free image editor, or a seasoned professional curious about what

‘‘that GIMP thing’’ is capable of, this book is designed to meet your needs and give you theinformation you’re looking for The idea is to cover everything that GIMP can do while alsoinvolving topics related to computer graphics in general The primary purpose of this book is

to show you how to be really productive with a program this complex If you’re anything like

me, the more cool things you can make and the faster you can make them, the more fun you’rehaving And really, it’s all about having fun This is especially true for a program like GIMP,which is developed by volunteers all over the world, in their free time, because they reallyenjoy it

That said, no piece of software is perfect and everyone has an opinion, myself included.Throughout the book, I may periodically voice my opinion about a feature in GIMP or a topic

in computer graphics However, when I do that, I try to make it a point to qualify that opinionand couple it with a relevant tip, trick, or workaround that’s actually useful to you

What to Expect

Unlike a lot of other books on the topic, GIMP Bible covers more than just the standard release

of GIMP GIMP’s primary function is that of an image editor and GIMP is typically used a lot

in photo editing However, it’s capable of quite a bit more, especially if you factor in the bevy

of extensions and plug-ins that are available For that reason, I also cover a variety of these veryhelpful plug-ins that are critical for digital artists who work in print, digital painting, video, andanimation

Another very important thing to note is that this book’s goal is to be as up-to-date as possible,

with a focus on the most recent features available GIMP Bible is targeted to cover the features

in the stable GIMP 2.8 release Consequentially, much of this book was written using the GIMP2.7 development series (the way GIMP versions work, odd decimals – 2.3, 2.5, 2.7 – are devel-opment versions and even decimals – 2.6, 2.8 – are stable) That being the case, there may besome minor inconsistencies between what you see on the screen and what you read in the text

or see in the figures The good news, however, is that by and large GIMP is still GIMP What

I mean is that while there may be some differences in how things look in GIMP, they shouldstill work the same A button may be moved or renamed, but it still performs the same function.Furthermore, to alleviate these issues, I will be diligently posting updates, errata, and tutorials tothis book’s companion website,www.wiley.com/go/GIMPBible

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Who This Book Is For

Because GIMP Bible is designed as a reference suitable for both beginners and experts in

pro-ducing computer graphics, it doesn’t presume to know your level of understanding of the field.Most terms and concepts related to computer graphics are explained in the text That said, we’vewritten this book with the assumption that you have at least a basic understanding of how yourcomputer works You should know how to start programs, open files, and install software onyour operating system The last of these is particularly important if you need to install some

of the plug-ins and extensions covered within this book On the hardware side of things, youshould also be able to use peripherals like a mouse or drawing pad and understand the differ-ence between system memory (RAM) and storage memory (hard drive or external media likeUSB sticks)

What This Book Contains

Looking through this book’s table of contents, you can get a good idea of all of the concepts and

topics that are covered GIMP Bible is organized into seven parts, The following is a description

 Part III: Manipulating Images — The focus of the chapters in this part is the cation of GIMP’s tools to manipulate existing images and create custom graphics It startswith moving, rotating, and deforming elements of your images and continues to cover howmuch you can modify your image by simply modifying its colors The final three chapters

appli-in this part really get appli-into addappli-ing new content to your images appli-in the form of text, paappli-intstrokes, and photo enhancement tools

 Part IV: Exploring Filters and Effects — One of the most prominent features of GIMP

is its incredibly wide variety of available filters Filters are sets of processing steps that can

be applied to your image in a single shot Their effects range from barely perceivable andsubtle to a complete overhaul of the appearance of your image The chapters in this partcover every one of the filters that ship with GIMP, as well as a few useful ones that don’t

 Part V: Advanced Topics — Part of the beauty of GIMP is its extensibility Anyone with

a computer and a little bit of programming knowledge can add new features and ality to GIMP in the form of extensions and plug-ins Throughout the rest of the book, Icover some of these ‘‘third-party’’ extensions that don’t come with GIMP by default The

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chapters in this part cover the installation of these additions and then go into how you caneasily write your own custom extensions to help improve your efficiency while working

 Part VI: Appendices — Most of GIMP Bible is focused on creating computer art and

graphics with GIMP In order to use GIMP for that purpose, however, there are some nical steps that you may need to perform to get GIMP installed on your computer and toget your hardware playing nicely with it The appendices provide you with those steps.They also cover supplemental information such as ways to customize the appearance ofGIMP and additional resources online where you can learn more about GIMP, includingthis book’s companion website,wiley.com/go/GIMPBible.com

tech-Conventions Used in This Book

As with any book on a technical topic, especially ones that deal with computer software, thereare specialized methods and terminologies that specifically relate to the software or the fieldbeing covered To deal with that, this book employs a few standards and conventions:

Terminology

Seeing as how this book is targeted at raw beginners as well as seasoned professionals (saltyexperts?) in computer graphics, I make it a point to define terminology and jargon specific to

the field or unique to GIMP You’ll be able to notice this because defined words, like megapixel,

will be italicized The definition will immediately follow If you run across a non-italicized wordthat you don’t recognize, have a look in the index of this book and see where else it’s used Thatshould give you enough context to figure it out on your own And if that still doesn’t work foryou, send me an email (given in the ‘‘Contact Information’’ section later) and I’ll do my best toclear things up for you

Commands, Options, and Menus

Throughout this book I continually make reference to various commands, options, and menus

in GIMP’s interface For many commands in GIMP, there’s often more than one way to invokethem So when I first give you a command, I’ll also provide each of the ways to perform it,including a keyboard shortcut if one exists by default If I reference a command more than once,then I typically just provide the fastest way to invoke that command

Often commands are invoked by navigating a menu In these cases, I use arrows to indicatedrilling down through submenus to the final menu item, like FiltersMapMake Seamless

Also, for both menu items and options that are in GIMP’s interface, I use title case when referring

to them That is, I’ll capitalize the first letter in each main word of the option or menu item, likeUse Color from Gradient Now, this choice may differ from the way it appears in GIMP, but cap-italization in GIMP’s interface is a bit inconsistent in parts Because I use uppercase letters in thisbook in a consistent manner, you’ll at least know what words to look for when going to GIMP’sinterface

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You may also notice that I may explicitly tell you whether to left-click, right-click, or (on sion) middle-click This is because working efficiently in GIMP requires that you have at least atwo-button mouse There’s a lot of functionality in dialogs like the Layers and Channels dialogsthat is most quickly accessed with a right-click There are occasions in the book where I sim-ply say click and don’t stipulate which mouse button to press In these cases any mouse buttonshould do, but it’s best to assume left-click.

occa-Using GIMP on Multiple Platforms

GIMP runs on every major computing platform, or operating system on modern computers,

including Linux, Unix, Mac OS X, and Windows The cool thing is that regardless of theplatform, GIMP typically looks and behaves the same That said, there are a few things to bear

in mind For instance, Mac users may be used to pressing the Command key for operations likecopy and paste However, GIMP’s current default is to use the Ctrl key across all platforms.Also, since printing, scanning, and screen capture subsystems vary from one operating system toanother, there are minor differences in the way GIMP accesses them These little inconsistenciesacross platforms can be a slight source of frustration for users who are used to working a certainway For that reason, whenever one of these differences pops up, I make sure to point out howGIMP handles them on each platform These differences are usually minor, though, so GIMPshould look the same on all platforms Since my preferred work environment (and GIMP’sprimary development) is in Linux, most of the screenshots in this book are taken from thatplatform However, for the relatively few places where there are differences on Mac OS X orWindows, I do have platform-specific screenshots

Another thing to note is that I occasionally need to refer to a location on your computer’shard drive Since most operating systems do it this way, I notate the path using the standardforward-slash notation, like so:/usr/share/gimp For those of you using Windows, yousimply need to translate to using back-slashes and drive letters And for you Unix folks, thethings you call directories and sub-directories (such asusrorsharein the previous example),

I refer to as folders and sub-folders How’s that for compromise?

Versions and Actively Developed Software

Since this book covers plug-ins that don’t ship with the official release of GIMP — plug-ins thatyou may have to download and install yourself — I’ve made it a point to try to use the mostcurrent stable version of each of these plug-ins This is particularly true for larger plug-ins likeG’MIC and Liquid Rescale, as well as extensions such as the GIMP Animation Package Whereit’s helpful, I mention the version of the plug-in and how it may differ from previous versions.The companion website for this book (wiley.com/go/GIMPBible.com) also has links to themost current versions of any of these plug-ins, and provides any tips you may need to follow inorder to get them installed

And as I mentioned earlier, GIMP Bible was written while GIMP was under heavy development

for the 2.8 series It was an interesting challenge, but my hope is that doing this gives you themost thorough look at the new GIMP so you can take full advantage of all of the goodies thedevelopers have packed into it for us Where it’s relevant, I’ll mention how the behavior of GIMP2.7/2.8 differs from the previous stable version and explain the benefits of the new behavior

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Features Used in This book

A common feature in Wiley’s Bible series of books is the very useful icons GIMP Bible uses these

icons to highlight discussion topics and provide you with quick tips, warnings, and workaroundsthat relate to those topics They’re there to help and they can often give you a really cool orunexpected way to use a tool or perform a particular task Skip them if you want, but you’ll

be missing out on the really good, juicy bits of information In this book, you’ll run across thefollowing icons:

addi-Tip

Tip features are the fun features They give you hints at how to take advantage of GIMP or use it more efficiently Also, in situations where a feature doesn’t work as you might expect it to, Tip icons explain how you can bend that feature to your will.

Contact Information

This book was not written in a vacuum A key tenet of the Free Software philosophy is theopen exchange of information Jason welcomes any reader’s questions, suggestions, complaints,and (hopefully) the occasional compliment The most effective way is through the blog andsupplemental tutorials on this book’s companion website atwiley.com/go/GIMPBible.com.This way if there’s anyone else out there who has the same question you do, everyonecan benefit from the answer Of course, you can also reach me directly via email at

author@gimpbible.com While I will definitely read each and every email, because of thevolume of email I receive, I cannot guarantee that I’ll respond to all of them immediately I do,however, promise to reply to any email that’s sent to me It just might take a while

I only have one request: please limit your emails to content that relates specifically to GIMP Bible.

If you have a bug report or feature suggestion for GIMP itself, please use the GIMP developeremail list or bug tracker Since I’m not an active GIMP developer, these are much more effectivechannels for those kinds of discussions

Alright, enough talk It’s time to get elbow-deep in GIMPy goodness!

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