. . . 136 11 Color Management with GIMP 139 11.1 Color Management in GIMP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139 11.1.1 Problems of a non Color Managed Workflow Workflow . . . . . . . . . . . . . . . . . . . . . . 139 11.1.2 Introduction to a Color Managed Workflow . . . . . . . . . . . . . . . . . . . . . . . 140 12 Enrich my GIMP 143 12.1 Preferences Dialog . . Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144 12.1.3 Color Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145 12.1.4 Image

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167 12.2.6 Select By Color Tool . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169 . . . . . . . . . . . 210 12.5 Color Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211 12.5.1 Color Balance Tool . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222 12.6.2 Color Picker Tool . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Scissors 123 Chapter 8: Paint Tools ................................................... 127 The Color Picker 128 Palettes 129 The Bucket Fill 130 The Blend Tool Or Gradient Fill 131 Pre-press Knowledge Chapter 13: Color Models ............................................ 187 RGB 188 CMYK 189 Indexed 189 HSV 191 NCS 192 Spot Color 193 vii i T h e G i m p Grayscale And Line Art 194 Complementary Or Inverted Colors 194 Chapter 14: Pre-press And Color In Gimp.................. 197 What Is Pre-press? 198 Printing From Gimp 198 Preparing For

cloning, etc. • Tile-based memory management so image size is limited only by available disk space • Sub-pixel sampling for all paint tools for high-quality anti-aliasing • Full Alpha channel support such as Script-Fu • Advanced scripting capabilities • Multiple undo/redo (limited only by disk space) • Transformation tools including rotate, scale, shear and flip • File formats supported include tools should be shown in the Toolbox, and their order. In particular, you can add any or all of the Color Tools to the Toolbox if you wish to. • Histogram overlays R, G and B histograms on the Value histogram

R Rect Select E Ellipse Select F Free Select Z Fuzzy Select Shift O Select By Color I Scissors B Paths O Color Picker M Move Shift C Crop and Resize Shift R Rotate Shift T Scale Shift S Shear accepts the new value you typed in a text field and returns focus to canvas. Space , Enter Activate current button or list Ctrl Alt PgUp , Ctrl PgDn In a multi-tab dialog selection Shift Ctrl V Named paste clipboard Fill Erase selection Ctrl D Fill with FG Color Ctrl D Fill with BG Color Ctrl D Fill with Pattern Layers PgUp , Ctrl Tab Select the layer above PgDn , Shift

and freehand tools. If that's not enough, you can use intelligent scissors, fuzzy selection by color, and even bezier selection. The program supports a full host of channel operations and many types into GIMP on the main menu include moving, magnification, cropping, transforming, flipping, text, color picking, fill, blending, pencil, paintbrush, eraser, airbrush, clone and convolve. Once you open the image is full-color, you should move the mouse to select "Filters," then "Conversions," and finally "To Color." We will abbreviate this procedure as "Filters->Conversions->To Color." Assuming that

will make all pixels in your image with the assigned colour transparent • In GIMP – Colors > Color to Alpha Use this tool to pan around the preview Preview, indicating which areas are to be transparent Ensure image is in RGB mode – Image > Mode > RGB • Assign a single colour to each image (v2.8) – Color > Colorify Pseudo-colour Overlays • Ensure image is in RGB mode – Image > Mode > RGB • Assign Search and Run a command – “Colorify” Colorify Replace all colors with shades of a specified color Pseudo-colour Overlays Or … Colors > Levels • Dial down the colours you don’t want • Once images

Josianne Mallia 3 Brief Notes on Introduction to Gimp Interface Tools • SELECTING FG COLOR AND BG COLOR Click on the colour you want and select your own colour palette colour in palette Choice Pattern has a choice Types of gradients available, either using FG Color or BG colour or a set of colours on their own Reverse colour choice A choice of different

completely black 5 In-Class Activity: Segmentation Using GIMP Segment the dendrites • Change the color to white using the toggle in the “main toolbox”, or by pressing X on your keyboard • In the “Layers” visualize the dendrites • Zoom in and out by holding the Control key and rotating your mouse wheel • Color the dendrite pixels white using a smaller pencil tool (size ~10). Be as accurate as possible! 6

Take out dust spots from a scanned image  Crop your image (get rid of unwanted edges)  Adjust color (brighten or darken) Basic photo editing in GIMP Open your image file in GIMP 1. File 2 2. Click on Auto White Balance – good to start out with. Brings your image to a baseline Color Enhance – can brighten up a dull picture Equalize – contrast correction between whites and blacks