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GIMP/Print versionIntroduction

GIMP (GNU Image Manipulation Program) is an open-source image editing program, licensed under the GNU General Public Licence. It can be used for editing electronic bitmap images like photographs. Whilst GIMP can edit vector graphics such as SVGs other programs such as Inkscape or Adobe Illustrator are far more capable. GIMP, as a fully functioning image editor, rivals other industry standard software such as Adobe Photoshop and Corel Paint Shop Pro in terms of features such as multiple layers, the ability to resize and re-shape images, cropping, colour manipulation, and so on. The project was started in 1995, and its first public release (0.54) was in January of 1996. Now, 13 years after its first release, GIMP is used by a variety of people ranging from professional graphic artists, to computer hobbyists of all ages who don't want to put down $700 for a copy of the newest Photoshop. Since its original release for Unix and GNU/Linux operating systems, GIMP has been ported to many major operating systems and platforms including Microsoft Windows and Mac OS X. GIMP requires the GIMP Toolkit (GTK), an advanced widget library created during the development of GIMP. If you download GIMP for any platform, you must first install GTK if it isn't installed already. Although this comes standard in most modern Linux distributions that ship with GNOME, it does not come standard with Windows nor Mac OS X. Additionally, GTK does not run fully native on Mac OS X and requires a special X Server package. Many image editing tutorials are available on the web. Some of the available tutorials can be used interchangeably, since the image-editing functionality provided by the GIMP and Photoshop or Paint Shop Pro are similar (images can be cropped, resized, colours altered, pixels erased, pixels added etc.). A moderately advanced GIMP user can follow Photoshop tutorials as if they were written for the GIMP, and vice-versa except when the tutorial uses a feature that one of the programs does not support. However, following a Photoshop tutorial using the GIMP (or any other image editor, in reality) as written can be difficult, or nigh impossible. Unfortunately, the GIMP lacks some

GIMP/Print version features that are commonly used in Photoshop, such as adjustment layers (which, for example, may affect the brightness or contrast of an image without permanently modifying it) and colorspaces other than RGB and grayscale (CMYK is essentially a necessity if you're wanting to print something). In most situations, luckily, these features do little more than just make your workflow a tad easier, thus there might just be a different way to achieve the same results. The current look of GIMP consists of 2 main windows - the image window and a toolbox. Also by default there's another utility window. The image window is always under the utility windows, but can easily go over by using the Tab key. Note that if you want to start using the GIMP right away, right clicking an image window will open a menu that gives access to most of the GIMP's editing tools and features. Obviously, all commands can also be accessed via the toolbar at the top of the window of the image you're currently working on. You can find out a lot more about GIMP on its website, http://www.gimp.org/ [1].

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The ToolboxGIMP provides a comprehensive toolbox in order to quickly perform basic tasks. Toolbox is fully customizable, this means that you can add/remove any tool you want. Just go to "Windows > Dockable Dialogues > Tools", and select any tool you want.

Toolbox from GIMP 2.6

By default not all tools are shown - GEGL operation tool and colour tools are omitted. All tools can also be accessed by opening the "Tools" menu. To switch the window to toolbox, you can use Ctrl + B. Note that shortcuts wrote here are the default values - you can change them any time you want in "Edit > Keyboard Shortcuts"

ToolsThese tools are available by default in toolbox.Icon Name Shortcut Selection tools Rectangle Ellipse Free (Lasso) Fuzzy (Magic Wand) By Colour Scissors Foreground R E F U Shift + O I (none) Selects square or rectangular regions. Selects circular or elliptical regions. Draw free-form selections. Select continuous regions of colour. Select all instances of a colour in an image. Create paths to select shapes. Select a region containing foreground objects. Brush tools Bucket Fill Shift + B Fills an area with a colour or pattern. Description

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3L N P Shift + E A K C H (none) Shift + U S Shift + D Fills an area with a gradient. Paints hard-edged lines; that is, the pixels are not anti-aliased. Paints soft- or fuzzy-edged lines; that is, the pixels are anti-aliased and/or feathered. Erases pixels from a layer. Paint tool with variable pressure. Paints anti-aliased lines with a simulation of a nib. Copies pixels from one part of an image to another. Heals image irregularities. Clone from an image source after applying perspective transformation. Blurs or sharpens an image. Spreads pixels in the direction of a "push". Lightens or darkens an image's shadows, mid tones, or highlights. Transform tools Move Align Crop Rotate Scale Shear M Q Shift + C Shift + R Shift + T Shift + S Shift + P Shift + F Other tools Path B O Z Shift + M M Allows selecting and modifying paths. Selects the colour of any image opened on your screen. Alters the zoom level of the image. Shows distances and angles. Places text into your image. Moves layers and selections. Align or arrange layers and/or other objects. Crops or clips the image. Rotates the active layer, selection or path. Scales the active layer, selection or path. Shifts part of the image to some direction. Changes the perspective of the active layer, selection or path. Flips layers and selections.

Blend (Gradient) Pencil Paintbrush Eraser Airbrush Ink Clone Heal Perspective Clone Convolve (Blur/Sharpen) Smudge Dodge/Burn

Perspective Flip

Colour Picker Magnify (Zoom) Measure Text

GIMP/Print version There are also some other tools, hidden by default. These tools need to be accessed from the "Tools" menu, or by showing them in toolbox (Windows > Dockable Dialogues > Tools).Icon Name Shortcut Colour tools Colour Balance Hue-Saturation Colourize Brightness-Contrast Threshold Levels Curves Posterize Desaturate (none) (none) (none) (none) (none) (none) (none) (none) (none) Modifies the colour balance of current selection or layer. Adjusts hue, saturation and lightness. Renders current selection or layer into a grey scale image seen through coloured glass. Adjusts brightness and contrast. Transforms the current layer or selection into a black and white image. Changes the intensity range of the active layer or selection in every channel. Changes the colour, brightness, contrast or transparency of the active layer or path. Reduces the number of colours. Converts all colour to the corresponding shades of grey. Other tools GEGL operation (none) Executes a GEGL operation. Description

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Tool optionsBy default, activating any tool, will have the effect of showing its options under the toolbox. Each tool has its own set of settings and any changes to them are kept through the current session. There are also four buttons under any options. Save options to... - save options of the current tool Restore options from... - restore options from saved file Delete saved options... - delete saved options Reset to default values - reset the settings to default values. You can hide them by clicking on the arrow next to the tool name and deselecting Show Button Bar. You can also access these from the same menu under Tool Options Menu.

Colour, Indicator and Active Image areaBelow the toolbox can be placed these three areas. This is set in "Edit > Preferences > Toolbox" and any of the three can be hid there.

Colour area

Colour, Indicator and Active Image areas respectively.

Shows current foreground and background colour. Clicking on either will bring up the colour editor dialogue. Clicking on the symbol in the lower left corner resets the colour to their defaults. The D key has the same effect.

GIMP/Print version Clicking on the symbol in the upper right corner swaps the foreground and background colours. The X key has the same effect.

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Indicator areaShows currently selected brush, pattern or gradient. Clicking on any of these allows you to change it.

Active Image areaDisplays a thumbnail of the active image. Clicking on it will bring the Images dialogue up, allowing you the select an image.

The BasicsShortcut: L The GIMP Blend tool enables you to make gradients. For instance, a gradient may be a paint fill or stroke which smoothly blends from red to green. A gradient may have sudden changes as well. And a gradient may be applied to selections or opacities. On the right side of the gradient dialog box, are the default settings: Mode - you can select mode here (more information in the Modes article) Opacity - set whether gradient will be transparent or fully visible Gradient - type of gradient Offset - effects how far along the start colour in the gradient begins Shape - shape of gradient Repeat - way of repeating Dithering - helps reduce banding by dithering the gradient.

Default gradient settings.

Adaptive supersampling - try to refine the gradient in high contrast areas. Choose how much difference is required before supersampling activates, and how hard GIMP tries to get good quality samples.

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OpacityThis bar controls the transparency of the gradient. Any value between 0.0 and 100.0 is possible with 100 being fully opaque and 0 being fully transparent. The default value is 100.

GradientThere are hundreds of types of gradients in GIMP. Neons, flags, flares and much more. All of them have their own effect, but only few use selected colours. Here's short description of them: FG to BG (HSV anti-clockwise) - using HSV palette, moves counter-clockwise FG to BG (HSV clockwise hue) - using HSV palette, moves clockwise FG to BG (RGB) - using RGB palette FG to Transparent - moves from foreground colour to transparent. ). It reverses the gradient direction. For example, Red to Green would

Next to it you can see a flip option ( flip to Green to Red.

OffsetGradient offset ranges from a default of 0, up to 100 percent. When offset is 0, the gradient begins at the start of the blending line. When offset is 50, the gradient begins at the halfway point in the blending line. Any earlier points are rendered with the same colour as the leftmost colour in the gradient. Setting offset to 100.0, which makes the gradient a solid (non-gradient) colour.

ShapeThere are eleven gradient shapes, clicking and dragging inside a selection makes the gradient follow its boundary. Linear - Smoothly blends from left to right Bi-linear - Smoothly blends to the left and right from the middle Radial - Linearly blends outward along radius - pseudo-spherical appearance Square - Linearly blends into a square from center to corner Conical (symmetrical) - blends linearly with angle in a circular arc Conical (asymmetrical) - blends linearly with arc, until reaching the starting radius Shaped (angular) - formerly shapeburst, produces an angular beveled gradient Shaped (spherical) - fills selection with a bulging beveled gradient Shaped (dimpled) - fills selection with a puckered beveled gradient Spiral (clockwise) - clockwise spiral blend centered at click, with varying amount of twist Spiral (counterclockwise) - counterclockwise spiral

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RepeatThere are three options for repeating: None - no repeat Sawtooth wave - once passing the end of the gradient, begins again at the start Triangular wave - once passing the end of the gradient, blends backwards until the start, and then begins blending forward again.. You can use Repeat with these shapes: Linear, Bi-linear, Radial, Square, Conical (sym), Conical (asym).Example of triangular wave ( using radial shape ).

DitheringDithering reduces banding patterns in the gradient. If your gradient includes deliberately banded areas, turn dithering off in order to preserve them. If the result must be very precise, consider turning dithering off also (dithering trades spatial resolution for colour resolution, which is only good if you have spatial resolution to spare.)

Adaptive SupersamplingAdaptive supersampling identifies areas that seem to have high contrast and tries to improve the precision of the rendering only at these points. The general effect is that areas of high contrast are smoothed out; One easy way to see this is comparing the appearance of a 'sawtooth wave' repeated gradient with and without supersampling enabled. The options in this section allow you to control How much contrast is considered 'high contrast' How much GIMP will try to improve the sample quality before accepting the result (this comes into action when the additional samples' relationship to each other is also considered as high contrast) See supersampling for a detailed explanation

The BasicsShortcut: M Move tool is used for moving anything on the image, including layers, selections and paths. Move - defines what will be moved Tool Toggle - toggle between the two available modes (for each option) You can toggle between the two options with Shift (temporarily).

MoveYou can choose what you want to move, as mentioned before it's either layer, selection or path.

Move tool menu.

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LayersTo move a layer, select this option. If the layers are grouped (chain symbol), all layers in the group will be moved. When this mode is selected, under tool toggle you'll see two options, "Pick a layer or guide" and "Move the active layer". The first one will move the layer that you select and the second one will always move the active layer.

SelectionsThe move tool allows you to move the selection outline. It has no options in Tool Toggle.

PathsYou can also move paths with this tool. Note that path tool has its own tool for moving. To use move tool, make the path visible in the path dialogue.

The BasicsShift + C The Crop tool can be used to crop or clip the image, working on all layers of the image (both visible and invisible). It can be used for removal of borders, or unwanted areas of the image to centre the focus on the work. To crop the image to selected size, double-click inside the box, or press Enter. The crop box can be resized by dragging at the edges and corners. To move it, click and drag on the crosshairs at the centre. Current layer only - works only on the current layer Allow growing - allows to expand beyond borders Expand from centre - expands selection, using starting point as the centre, instead for the corner Fixed - allows you to modify the actual shape of rectangle Position - placement of the selection to crop Size - size of the selection to crop Highlight - highlights the actual selection, by darkening everything that surrounds it Guides - select the types of guides shown within of selection Auto Shrink - shrinks the selection to the nearest rectangular shape available on the image layer Shrink Merged - if this option is enabled, then Auto Shrink will use the pixel information from the visible display of the image, rather than from the active layerCrop tool menu with default settings

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Current layer onlyCrop tool will only work on the currently selected layer, instead of working on all existing.

Allow growingAllows Crop tool to expand beyond borders of the image/layer, and crops along with the outside area.

Other optionsAll other options work as described in ../Rectangle Selection/ article. See sections #Expand from centre to #Shrink merged

The BasicsThere are 7 selection tools. Each has its own properties, but all have something in common. All of these common options will be described here, while their variations on the tools pages. The tools are: Rectangle Select Tool Ellipse Select ToolAll seven selection tools.

Free Select Tool (Lasso) Fuzzy Select Tool (Magic Wand) Selection by Colour Tool Scissors Select Tool

Foreground Select Tool The paths tool can be considered as a selection tool, but it doesn't share any options. It can be used as a tool for creating complex selections, especially ones that follow natural curves. To convert a path to a selection you can use Select > From Path (Shift+V). There is also a quick mask mode, used for creating and editing selections using the paintbrush or any other drawing tools. It can be found under Select > Toggle Quick Mask (Shift+Q). The common options are: Modes - determines the way of creating the selection, whether it will be combined with existing one and such Anitaliasing - causes the boundary of the selection to be drawn smoother Feather edges - causes the boundary of the selection to be blurredBasic options.

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ModesModes determine whether the selection will be added, subtracted or intersected from existing one, or either replace it. Functions performed by these button can be duplicated using modifier keys, as described later. Many people find this very useful. Replace - default mode, replaces the existing selection Add - adds a new selection to the existing one Subtract - removes the new selection from already existing region Intersect - makes a new selection from the region when both the new and old one overlap

AntialiasingThis option only affects few of selection tools. It causes the boundary of the selection to be drawn more smoothly.

Feather EdgesFeather Edges blurs the boundary, by selecting the boundary pixels only partially. This allows the selection to smoothly blend with the background.

Key modifiers (defaults)The behaviour of selection tools can be modified by holding down Ctrl, Alt and Shift. Ctrl - has two options depending on what you are doing while creating a selection toggles Expand from centre option while doing nothing, this key switches to Subtract mode, as long as you hold it Alt - allows movement of the current selection (only its frame, not content). If the image is moved instead, try Shift + Alt Shift - similarly to Ctrl, it has two options depending on what you are doing before starting a selection, this key will switch to Add mode, as long as you hold it after starting a selection, it will depend on tool you are using - for example for Rectangle Selection, it will create a square selection Ctrl + Shift' - depending on which tool is used, different thing will happen. A common option however is switching to Intersect mode Ctrl + Alt + Click-and-drag and Shift + Alt + Click-and-drag - allows movement of the current selection (its content) Space bar - transforms the tool to Navigation cross as long as you press the bar, allowing you to pan around the image, instead of using scrollbars. In Preferences > Image Windows you can toggle the Space bar to the Move tool

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The BasicsShortcut: R The rectangle selection tool is a simple but useful tool. It allows you to create rectangular selections. Modes - determines the way of creating the selection, whether it'll be combined with existing one and such Antialiasing - causes the boundary of the selection to be drawn smoother Feather edge - causes the boundary of the selection to be blurred Rounded corners - rounds the corners of the selection Expand from centre - expands selection, using starting point as the centre, instead for the corner Fixed - allows you to modify the actual shape of rectangle Position - placement of the selection Size - size of the selection Highlight - highlights the actual selection, by darkening everything that surrounds it Guides - select the types of guides shown within of selection Auto Shrink - shrinks the selection to the nearest rectangular shape available on the image layer Shrink merged - if this option is enabled, then Auto Shrink will use the pixel information from the visible display of the image, rather than from the active layer

Default rectangle selection tool settings.

Modes, Antialiasing and Feather EdgesSee Selection Tools#Modes for information about Modes See Selection Tools#Antialiasing for information Antialiasing See Selection Tools#Feather Edges for information about Feather Edges option

Rounded cornersA slider appears after enabling this option. Use it, to change the radius that is used to round the corners

Expand from centreAfter enabling this option, the starting point is used as the centre of the selection instead of using it as a corner. This also causes that the selection is extended from all sides. This option can be enabled with Shift.

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FixedThis option allows you to modify the shape of rectangle in four ways: Aspect ratio - allows you to desing the selection, while keeping the aspect ratio fixed. By default it is 1:1, which makes a square. There are two little icons next to it (landscape and picture) Width - you can fix the width of the selection Height - you can fix the height of the selection Size - you can fix both, width and height of the selection

PositionThe actual placement of the current selection. This will show the placement of upper left corner, or centre, if Expand from centre option is enabled. You can use it to modify

SizeThe actual size of the current selection. You can use it to modify the size, as well as resizing it directly on the image.

HighlightEmphasizes the selected area by a surrounding mask, making the visual selection much easier.

GuidesIn here you can set what guides will be shown within the selection, respecting Photo composition rules. No guides - no guides are shown Centre lines - only the centre lines are visible Rule of thirds - guides are shown along the rule of thirds Golden sections - guides show up to mark the golden sections

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Auto ShrinkAfter pressing this button, already having a selection, it will shrink to the nearest rectangular shape within the selection. The algorithm for finding the best rectangle, can once do a great work, and sometimes find some strange rectangles.

Shrink mergedIf this option is enabled Auto shrink will look on the actually visible image, rather than the active layer.

The BasicsShortcut: E Ellipse selection is quiet much as the rectangle one. The only difference is the fact that it has one option less - rounded corners, as it is elliptical selection so for what. As the name suggests it is made for creating elliptical and circle selections, with option high quality antialiasing. Modes - determines the way of creating the selection, whether it'll be combined with existing one and such Antialiasing - causes the boundary of the selection to be drawn smoother Feather edge - causes the boundary of the selection to be blurred Expand from centre - expands selection, using starting point as the centre, instead for the corner Fixed - allows you to modify the actual shape of rectangle Position - placement of the selection Size - size of the selection Highlight - highlights the actual selection, by darkening everything that surrounds it Guides - select the types of guides shown within of selection Auto Shrink - shrinks the selection to the nearest rectangular shape available on the image layer Shrink merged - if this option is enabled, then Auto Shrink will use the pixel information from the visible display of the image, rather than from the active layer

Default ellipse selection tool settings.

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All other optionsSee Rectangle Selection for information about the tool as everything works completely (or almost completely) the same. The only difference is existence of rounded corners option in Rectangle Selection - there is no need for it here.

The BasicsShortcut: F Free selection tool (also called 'Lasso') let's you create a selection by drawing it free-hand (with the pointer and holding down the left mouse button, of course). It is the only selection tool, that has nothing more than the basic options. The selection is finished with a straight line and it actually possible the create straight lines by clicking (not holding!) on one point and making another one somewhere away from it. Modes - determines the way of creating the selection, whether it'll be combined with existing one and suchDefault free select tool settings.

Antialiasing - causes the boundary of the selection to be drawn smoother Feather edge - causes the boundary of the selection to be blurred

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The BasicsShortcut: U Fuzzy selection (also called 'magic wand') is a tool for selecting areas of image (or layer) with the same/similar colour. It is very important to pick the starting point correctly, or either you will get something completely different from what you want (well, not always, but usually yes). Wand is a good choice for selecting objects with sharp edges. It is also great for touching up selections, or selecting areas within some contour. Modes - determines the way of creating the selection, whether it'll be combined with existing one and such Antialiasing - causes the boundary of the selection to be drawn smoother Feather edge - causes the boundary of the selection to be blurred Select transparent areas - gives the ability to select areas completely transparent Sample merged - creates a selection from actual image, instead from the active layer Threshold - determines the range of colours Select by - select, which component shall be used for calculating the similarityDefault fuzzy selection tool settings.


Select transparent areasAfter selecting this option, the Free Selection tool will have the ability to select completely transparent areas. If this option is unchecked, transparent areas will never be selected.

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Sample mergedThis option has any meaning when you have several layers on the image, and the active layer is either semi-transparent or set to another mode than Normal. If it is so, the colours present in the layer, will be different from the ones in the real image.

ThresholdThis slider determines the range of colours that will be selected at the moment of creation of the selection. Higher threshold - larger resolution. Note that with higher selection also bigger gaps are possible to be between the selections. After the first button-press (but before releasing it), dragging the pointer downward (or to the right) will increase the size of the selection, while dragging upward (or to the left) will decrease the size of it. Thus the first settings of threshold do not really matter, as you can modify them any time afterwards.

Select byThis option will change the component that The GIMP will use for calculating the selection. The possible components are: Composite. Red, Green, Blue, Hue, Saturation and Value.

The BasicsShortcut: Shift + O Select by colour works really similar to the Fuzzy Selection tool. The main difference is that when magic wand makes selection with no real gaps, selection by colour takes all the pixels with similar colour, regardless to where they are located. Modes - determines the way of creating the selection, whether it'll be combined with existing one and such Antialiasing - causes the boundary of the selection to be drawn smoother Feather edge - causes the boundary of the selection to be blurred Select transparent areas - gives the ability to select areas completely transparent Sample merged - creates a selection from actual image, instead from the active layer Threshold - determines the range of colours Select by - select, which component shall be used for calculating the similaritySelection by colour tool settings.

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All other optionsSee Fuzzy Selection for information about the tool as everything works completely (or almost completely) the same.

The BasicsShortcut: I Scissors is an interesting selection tool. It has some features of lasso, some features of paths tool and some of its own. It is useful for selecting a region defined by strong colour changes at the edges. To use scissors, you need to create a set of 'control nodes' (also referred to as anchors), at the edges of the region you are willing to select. The tool creates a curve trough these nodes, following any high-contrast it can find. Each time you press left mouse button, you create a new anchor that is connected to the last control node by a curve. If you want to finish the selection, just press on the Default scissors tool settings. first node you've created. After that you can adjust the selection by modifying the curves or by moving/creating new nodes. When you are satisfied just press anywhere inside of the selection to create it. Modes - determines the way of creating the selection, whether it'll be combined with existing one and such Antialiasing - causes the boundary of the selection to be drawn smoother Feather edge - causes the boundary of the selection to be blurred Interactive boundary - the curves will be created instantly after creating a new node


Interactive boundaryWhen this option is active, the curves between nodes will be really curves. Normally (when the option is disabled) there will be only straight lines until you finish the selection.

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The BasicsShortcut: none This tool lets you extract foreground from the active layer, using the SIOX method. To create a selection, set roughly foreground you want to extract. Select as little of the background as possible. As soon as you're finished (the selection is closed) the rest of the image goes dark. Now draw the line trough the foreground, going through all colours that will be used for extraction. Then after releasing the mouse-button, only the actual foreground is selected. Remember to press Enter after finishing the selection, or you could actually loose it. Modes - determines the way of creating the selection, whether it'll be combined with existing one and such Antialiasing - causes the boundary of the selection to be drawn smoother Feather edge - causes the boundary of the selection to be blurred Contiguous - if this option is enabled, only area contiguous to the stroke is selected Interactive refinement - settings for the brush Smoothing - controls the smoothness of selection Preview colour - colour of the selection background Colour Sensitivity - set the sensibility for colours of the selectionDefault foreground selection tool settings.


ContiguousWhen this option is enabled, only areas contiguous to the stroke will be selected. When this option is not enabled, all areas of the same colour in the rough selection will be selected.

Interactive refinementThe following options are for controlling the brush of foreground select tool.

Mark foreground/backgroundWhether foreground or background colour will be used for the stroke. Ctrl is used to toggle between those. Remember! background colour is used for erasing.

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Small/Large brushThis slider lets you adapt the size of the brush. Small brush is good for details, while large is good for general foreground selection.

SmoothingThis slider lets you to remove holes in the selection. Also remember - smaller values may create a better border but include these holes in the selection.

Preview colourSelected colour will be used to mask the image background. Possible options: red, green, blue.

Colour sensitivityThis option uses L*a*b colour model. If your image contains many pixels of the same color in different tones, you can increase the sensibility of the selection for this colour.

The BasicsShortcut: O On the right side you can see default settings for colour picker. Here's short ( and then long ) description about everything there: Sample average - set whether to pick average value from pixels Sample merged - set whether all samples to be merged Pick mode - modes Use info window - set whether you want to see the info window

Sample AverageThat's the first option, by default unchecked. When in use, it will take all pixels from some radius (number of pixels in each direction), and pick the average value. The radius value is by default set to 3, but can be anything between 1 to 300.

Default colour picker tool settings.

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Sample MergedTakes colour information from all visible layers.

Pick ModeThere are four modes in the colour picker tool. Here are their descriptions: Pick only - only picks a colour, doing nothing to it (information dialogue must be turned on); Set foreground colour - picked colour is used as foreground colour; Set background colour - picked colour is used as background colour; Add to palette - adds the colour to the palette, especially useful while creating palettes; Ctrl switches between Set foreground colour and Set background colour, when either of these is active.

The info window.

Info WindowShows an info window, with two columns of information - you can choose for both of those these options: pixel, RGB, HSV and CMYK, with pixel and RGB being active by default. Shift toggles it on and off.

Zoom ToolShortcut: Z Zoom tool is used for magnifying a selected part of the image. First option is called Auto-resize window. By default it's disabled, by enabling it, it will resize the window according to the size of the magnified area. Underneath are two other options, for zooming in or out. As mentioned later, you can toggle between those two using a keyboard shortcut. By selecting an area of the image, you can zoom in/out on that area.Magnify tool menu.

GIMP/Print version Key Modifiers (defaults) Ctrl - changes direction of zooming; Ctrl + Mouse Wheel - spinning the mouse wheel, without clicking, varies the zoom.

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Measure ToolShortcut: Shift + M The measure tool measures length of the visible line, width, height and angle shown in the status-bar. In the tool options there is a check-box Use info window, if checked a window will show itself when you begin measuring providing you with the same details as before. Use info window is disabled by default.

Measure tool menu.

Key Modifiers (defaults) Shift - starts a new measure from the point the lasts end, without deleting the old one; Ctrl - puts the tool into straight line tool, also creates a horizontal guide; Alt - creates a vertical guide; Ctrl + Alt - allows to move the measure, also creates both horizontal and vertical guide.

The Basics

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Shortcut: T The text tool is used for creating and editing text layers. On the right side you can see default settings for text tool. Here's short ( and then long ) description about everything there: Font - select the font you want to use Size - set the size (height) of the font Hinting - modifies the characters to produce clear letters in small font sizes Force auto-hinter - tries to automatically compute information for better representation of the character font Antialiasing - renders the text smoother Colour - the colour of the text Justify - set the justification of the text Indent - controls the indent spacing from left margin Line spacing - controls the spacing between the lines of text Character spacing - controls the spacing between the characters Text along Path - puts the text along path Path from Text - creates selection path from selected text

FontThere's only one way for selecting a font in the GIMP. To do so use the font selector in this toolDefault text settings.

SizeTo set the size of the font just enter a value in the box, or use the arrows. You can choose from few units, by default in pixels, size of 18.

HintingUsing the indices of adjustment, modifies the characters, to make them look clear in small sizes.

Auto-hinterAuto-hinter, tries to automatically compute information to make a better representation of the character font.

AntialiasingSee Antialiasing for more information Renders the text with smoother edges and curves. This option can improve the visual appearance of the rendered text.

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ColourColour of the text, default is black. The colour of the text when writing, won't change instantly. You need to rewrite the text in that colour, or select the text and change it then.

JustifyJustifies the text according to the selected option. The options are: Left justified Right justfied Centered Filled

IndentControls the actual spacing from left margin. By default set to 0.0

Line spacingSpacing between lines. By default set to 0.0, although the spacing is not in fact 0 pixels then. The value can go under 0.

Character spacingSpacing between characters. By default set to 0.0, behaves the same as line spacing settings.

Text along PathYou need to create a path before. The path becomes once visible when using this option. The text is bent along the path, representing letters with their outline. Each of them is a component of the new path. All path options should apply to this path.

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Path from TextCreates selection, using the text. Every letter is surrounded with paths, so you can modify the shape of it, by moving the nodes.

Text editorThis dialogue is opened when you click with text tool on the image window. The text you enter directly appears on the image. If the option "Show Layer Boundary" is checked in the view menu, the layer will be surrounded with black and yellow dashes. You can easily move the text with the Move tool, but you need to click on the text - it's not selection. As soon as you start writing, the layer appears in the layer dialogue. After that you can easily resume the text, if you are still editing the image, or if it is an .xcf file. To add more text to the image, click on a non-text layer, and new text editor appears. So there are these five options there: Open - loads the text from a file Clear - clears the text area LTR - the text will be entered from left to right RTL - the text will be entered from right to left Use selected font - whether it will use the font from options dialogueText editor window.

OpenUsing this option, you can directly load the text from a file.

ClearClicking this icon, will cause erasing all text from the text area.

LTR and RTLLTR - the text will be entered from left to right, as with most Western and Eastern languages RTL - the text will be entered from left to right, as with all Arabic and some Eastern languages

Use selected fontBy default the font from the options dialogue is not used. Check this option if you want to use it.

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Editing an ImageImage OperationsImage operations not offered in the toolbox are accessed by right-clicking on the image. In Gimp 2.0, there is also an option to display this menu at the top of the screen. (This option is now default) Right-click on the image to access the menus. For example, Right-click, File, Save is used to save the image. PNG or JPEG formats are available for use on Wikipedia. To decrease a JPEG's filesize, adjust the Quality slider when you save. Often, it's useful to get info on an image you're editing. To do this, right-click on the image to bring up the menu, and then choose Image > Image Properties, or hit Alt-Enter. The first three properties are very important for printing: Pixel Dimensions, Print Size, and Resolution. Image > Canvas size is used to adjust the size of image dimensions, but does not attempt to scale the image. Image > Scale image is used to change the size of the image, for example to create thumbnail images. To remove a section of image, just select it (using one of the select tools) and press Control-K ("kill", same as using Edit > Clear). This will either erase the selection to the background colour, or to transparency if the image supports it.

Colours and Transparency

An Image Properties box.

GIMP can understand a number of different colour formats with a varying degree of support. It supports three so called modes: RGB, grayscale, and indexed. To change the mode of the image, choose in the menu from Image > Mode > ....

Colour ModesGIMP supports the following color modes: True Colour (RGB): This has the best support in GIMP. It is made up from 3 channels of 256 tonal variants, making a total of 16.7 million colours - 256 * 256 * 256. Supported formats: XCF, PNG, TGA, TIFF, SGI, BMP. Grayscale: The grayscale mode uses one channel to display a gray image. GIMP supports grayscale well and is usable for most tools that don't specifically require colour information. Supported formats: XCF, PNG, TGA, TIFF, SGI. Indexed: In this mode, the image consist of pixels picked from a palette of up to 256 colours. When you convert an image into this mode, or when you are reducing the color depth of an image, dithering options give you control over how colours are scattered. For the best quality results (especially with pictures that have

GIMP/Print version gradual tonal variance) use Floyd-Steinberg dithering: it will give a grainy texture to the picture, but reduce visible banding between different colours. On the other hand, reduced or no dithering will result in smaller files when saved as GIF or PNG. Supported formats: XCF, PNG, GIF, BMP. Monochrome: Two colours, often black and white. GIMP sees this as an indexed image with only 2 colours. Supported formats: XCF, PNG, GIF. Menu items for color modes: Image > Mode > RGB Image > Mode > Grayscale Image > Mode > Indexed

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Alpha ChannelRegardless of the mode, images can have an optional alpha channel for transparency. An image with an alpha channel can have transparent and semitransparent pixels, the degree of transparency of each pixel ranging from 0 to 255. Using transparency enabled by alpha channel, you can create a picture by stacking several layers on top of each other, save images for the web, or create images for 3D graphics that have holes or semi-opaque areas. Formats that fully support alpha channel: XCF, PNG, TIFF, TGA, SGI. Formats that only support alpha channel as fully opaque or fully transparent: GIF, XPM. Only Internet Explorer versions later than version 7 support transparency. Internet Explorer 6 and earlier do not. Menu items for alpha channel: Layer > Transparency > Add Alpha Channel Layer > Transparency > Remove Alpha Channel Layer > Transparency > Add to Selection

Colour Filter/ToolsImage, Mode, Decompose will split a colour image into a set of greyscale images, based on various colour models. Image, Mode, Compose does the opposite, combining greyscale images into colour ones. Striking effects may be obtained by recombining channels in a different model or order than they were decomposed in. A number of colour adjustments can be found under Colours, and colour effects under Filters, Colours

Saving the ImageThis shows a typical image editing window in the GIMP (this is version 1.2, more recent versions will have a set of menus at the top of the image window) Right-click, File, Save is used to save the image. A filetype can be selected (png, jpeg, etc.) from the dropdown list, but the default action is to use whatever extension was typed (specifying "image.jpg" causes it to save a JPEG file) After the filename is specified, there is an additional dialog box specific to each filetype. For example, a JPEG image will ask you for the compression level, and it can be useful to adjust this until the image is a reasonable filesize.

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Image formats Supported by GIMPas of GIMP 2.2.13

Significant file formatsFile Format XCF Extension(s) Description

.xcf/ .xcf.gz/.gz/.xcfgz/ .xcf.bz2/.bz2/.xcfbz2/ .gbr/.gih/.pat

GIMP's native format which will preserve all image data, including layer, the current selection, channels, transparency, paths and guides, but it doesn't save undo history. XCF images take up a lot of space, and are not supported by most image viewers, which is why XCF is only good for saving images for future editing (not for image exchange). There is also an option to compress the XCF by using either gzip (using xcf.gz/gz/xcfgz extension) or bzip2 (using xcf.bz2/bz2/xcfbz2 extension) compression. GIMP's other native formats include GIMP Brush (.gbr), GIMP Animated Brush (.gih), and GIMP Pattern (.pat). Bitmap is an uncompressed image format, which is the internal image format for Windows and OS/2 Graphic Subsystem. Graphic Interchange Format is often used for screenshots and computer graphics. It is lossless if the image has under 256 color or otherwise it become lossy. It allows transparent mask, which means a pixel can only be fully transparent or fully opaque, and not partially transparent. Hypertext Markup Language. GIMP will save in HTML as a HTML page that contains a table containing the image. Icon Image File Format is Windows' image format for icons. Joint Photographic Experts Group is typically used for photographs. It uses lossy compression that results in a loss of detail, commonly called artifacts. The artifacts are usually most noticeable on images that have sharp edges, while less noticeable on photographs, which have many smooth gradients. Portable Network Graphic is often used for screenshots and computer graphics. It uses lossless compression. It allows full alpha transparency. Portable Pixmap. PNM (Portable Any Map, a shorthand for ppm, pbm, and pgm format), PPM (Portable Pixel Map), .pbm (Portable Bit Map), .pgm (Portable Gray Map) and .pam (Portable Arbitrary Map). Postscript Document and Encapsulated Postscript

BMP

.bmp/.dib

GIF

.gif

HTML

.htm/.html

ICO JPEG

.ico .jpg/.jpeg/.jpe

PNG

.png

PNM

.pnm/.ppm/.pbm/ .pgm/.pam .ps/.eps

PS and EPS PSD TGA TIFF XBM XPM

.psd .tga .tif/.tiff .xbm .xpm

Photoshop Document, the native format of another popular graphic editing software, Adobe Photoshop. Truevision Graphics Adapter, Targa's native image format. Tagged Image File Format X Bitmap 2-bit, Monochrome Bitmap for X Window System X Pixelmap Color Bitmap for X Window System

Other less popular image format also supported by GIMP:

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Extension(s) .pix/.matte/.mask/.alpha/.als .fli/.flc .c/.h .dcm/.dicom .fit/.fits .cel .sgi/.rgb/.bw/.icon

Description Alias/Wafefront Pix Image Autodesk FLIC Animation C/C Header Sourcefile Format Digital Imaging and Communications in Medicine Image Flexible Image Transport System KISS Cel Silicon Graphic IRIS Image

.im1/.im8/.im24/im32/.ras/.rs SUN Rasterfile Image .pcx/.pcc .xwd ZSoft PCX Image X Windows Dump

Other file formats that GIMP can only read, but not write:Extension(s) .g3 .wmf/.apm .psp/.tub .pdf .svg .fit/.fits Description G3 Fax Image Microsoft WMF File Paintshop Pro Printable Document File Scalable Vector Graphic Flexible Image Transport System

GIF imagesThe Unisys patent has now expired and in recent versions of the GIMP you should be able to save compressed GIF images using GIMP. If your version will not save GIF files and it is updated, you may want to update the corresponding image libraries for GIF.

Saving as JPEGWhen saving as a JPEG, you should let the image itself dictate the quality rather than reusing settings. The same settings for one image may produce significant loss on another.

Basic SettingsQuality: the overall quality of the output JPEG. The lower this value is the more compression you'll attain, at a cost to visual quality. Generally you'll want the lowest quality with no significantly noticeable loss. Start at the default and adjust to the best compromise for the image. You shouldn't usually go above 95, as the size grows significantly for no noticeable quality gain. Likewise, you shouldn't go below ~25 as banding may occur. The Show Preview in image Window option creates a new layer with how the image will look with the current settings. It updates in real-time as you change the settings. You can zoom or hide as usual to get a better look at the quality.

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Advanced SettingsThese can be uncollapsed by selecting the box next to Advanced Settings and are saved for the current session, along with most other saving settings.

LossyThese settings alter the actual image to help with compression. Changing these will change the overall subjective quality of the image.

Force Baseline JPEG:Enabling this option will force Gimp to make a JPEG which can be read with all decoders, often at a loss to quality and size, especially at lower quality settings.

Smoothing:Setting the smoothing option to a non-zero value will smooth out the image slightly. This reduces fuzzy artifacts from compression, and helps with the compression. A setting of 0.10-0.15 removes a good portion of the artifacts without smearing edges.

Subsampling:Gimp allows three subsampling modes. Subsampling discards more colour information (which is harder to discern) compared to luminance. Subsampling improves image compression at a cost to image quality, sometimes a significantly noticeable loss (such as on red), or no noticeable difference at all. Subsampling on an image where it shouldn't be used will smear the detail, most noticeably on sharp edges. If you notice significant loss with the default, you can turn it off by selecting "1x1x1x1", which is technically no subsampling.

DCT Method:The 'Floating' DCT method produces slightly better results than the 'Integer' method with a slight cost to speed. 'Fast Integer' should only be used where speed is imperative.

LosslessThe following settings can losslessly be set; they don't affect the image's quality in any way.

Optimize:Optimizes the images table for a gain in compression. Unless speed is a concern, there's no reason to turn it off.

Comment:If you wish, a comment of your choosing can be set for the image, such as the quality settings, or a synopsis of how the image was made.

Save EXIF Data:Some cameras save information about the image, such as when it was taken or even if the flash was on. If you have no need for this information in the image you can safely turn it off. When saving an image that has no EXIF data present the option will be grayed out.

Save Thumbnail:The JPEG format allows for a thumbnail of the image to be saved into the actual file itself. Most software using a thumbnail can generate one of its own and saving your own is unnecessary, as well as adding several kilobytes to the image size.

Progressive:Selecting Progressive will change the encoding to display the image at increasingly higher quality levels until the image is fully loaded. Progressive encoding also benefits the image's compression. Leaving this option unchecked will switch to Standard encoding, where the image is displayed in rows from top to bottom.

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Restart Markers:Restart markers are useful when data corruption can occur; the image will only be corrupt up until the next marker. Setting this higher increases the frequency of restart markers at a cost to filesize. Without restart makers, if any corruption occurs, the entire file can be compromised.

LayersLayers in the GIMP are a powerful tool allowing you to do many things. A good way to think of them is as layers of glass stacked up. Layers can be transparent, translucent or opaque.

The Layer DialogGo to Windows > Dockable Dialogs > Layers to open the layers dialogue. This dialogue is useful when editing with layers.

StartingOpen up the layers dialogue, and add as many layers as you like to the image. Note that any image editing or filters will only apply to your currently selected layers.

TransparencyThe Opacity slider controls the transparency or opaqueness of a specific layer. This will not affect the internal alpha channel of the layer.

Layer MaskA layer mask is a grayscale layer that controls the local transparency of a layer. This is useful for non-destructively deleting part of a layer, or only making part of a layer visible.

Using a Layer Mask to selectively edit an imageA layer mask is a very useful tool if you only want to edit part of an image. First duplicate the layer that you want to edit. Then make your changes to the bottom layer. Now add a black layer mask to the unchanged layer. Then use the white paint brush on the layer mask, to restore parts of the original version. A black area in a layer mask will have zero opacity, while a white (RGB 255,255,255) area will be completely opaque.

ChannelsChannels are very similar to layers, however, each layer corresponds with a particular level in the color model of the image (RGB, HSV or CMYK). Channels can be selected in any combination, and are shaded gray if currently active. You can also view and edit the channels separately, making changes to a single color while viewing the full-color image in your image window. Choosing what channels to display is done the same way as choosing what layers to display. Simply click the box next to it, and an eye will appear, indicating that the channel is displayed. Keep in mind, a channel can still be edited even if it is not displayed. This can lead to problems if you don't catch it early, and may require undoing a large number of edits to fix. At the time of this writing, GIMP only supports the RGB (Red, Blue, Green) and the HSV (Hue, Saturation, Value) representation of the color model. CMYK isn't natively supported by GIMP, but a plug in giving some functionality is available at the website below. http://www.blackfiveservices.co.uk/separate.shtml

GIMP/Print version The GIMP also supports the adding of custom channels allowing for even more advanced editing.

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DecomposeThe Decompose tool will decompose a colour image into a series of grey scale layers. This allows you to edit the image in many different colour models.

DecomposeGo to Colours > Components > Decompose. This will bring up the Decompose Dialog. The Decompose window looks like this:

Select the colour model that you wish to use from the drop down menu that matches the colour model you wish to split to.

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RecomposeWhen done editing your image, select Colours > Components > Recompose, to recompose the image back into an RGB Image. When saving to the XCF format, the layers will be preserved.

Levels ToolThe levels tool is an easy and powerful tool for adjusting the tones of an image. It allows more precise control of contrast than the Brightness-Contrast tool, but doesn't give the user the complete control of Curves.

Input LevelsInput levels control the contrast of the picture. The end points control the black points, and the white points. The eyedropper buttons next to the black and white input level markers allow black and white points to be selected in the image. The middle pointer can be used to selected the gamma correction value for the image. This tool can be used to simulate setting a white point. For images such as Image:PSF B-70002.png, setting a white point is critical in extracting useful images such as Image:Backstroke (PSF).png.

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Curves ToolCurves is a powerful tool found in The Gimp, it can be used for many things, such as fixing a colour cast.

To use the curves tool, go to Tools > Colour Tools > Curves and you should see a window similar to this: You can adjust the "Value" channel, which will brighten/darken the image depending on whether you drag the line up or down. Down will darken, up will lighten. You can also adjust the Red, Blue, Green, and Alpha channels. If your picture has a green colour cast, open up Curves, switch to the green channel, then move the line toward the bottom a little bit, until the cast is gone. You can also switch the curve style, from smooth to jagged.

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Gaussian BlurThe Gaussian Blur filter blurs an image or selection. The radius affects the strength of the blur. Besides for creating a fuzzy image, the Gaussian Blur has a few other uses. If you are working on an image with edges which one deems to be overly rough, one could use a blur radius of 1 to soften the image slightly, yet less dramatically than using a larger radius or the standard Blur filter. It is also very useful for a variety of image effects, such as shadows.The Gaussian Blur filter can be found by going to Filters > Blur > Gaussian Blur.

IIR vs. RLEThe filter supports two methods of Gaussian Blur: IIR and RLE. They both produce the same results, but each one can be faster in some cases. IIR (Infinite Impulse Response) works best for large radius values or for images which are not computer generated, such as photographs. RLE (run-length encoding) works best for computer-generated images or those with large areas of constant intensity, such as logos.

Selective Gaussian BlurThe Selective Gaussian Blur filter will selectively apply a Gaussian Blur to areas of a picture with less detail, leaving the areas with detail untouched. This can be used for cleaning up noise in a picture.An example of the dialogue window of the Gaussian Blur filter. It contains a preview of an image with the blur radius set to 5.0.

PixelizePixelize filter is for pixelizing the image, as the name suggests. The only thing you can set there is size of those "pixels". Default value is 10x10.

Unsharp MaskThe Unsharp Mask filter performs a better job than the standard Sharpen filter by applying the sharpening selectively to a blurred version. Unsharp Mask tends to leave noisy sections of the image untouched. Sharpening is a very desirable effect on blurry images or those which have been rescaled. Things are naturally sharp in your vision.An example image of the effect.

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Note that the Unsharp Mask, like all other sharpening methods, will produce an aura around the edges if set too high.

An example of the dialogue window of the Pixelize filter. It contains a preview of an image with the pixel size set to 10x10

Sharpening BasicsUnsharp mask increases the apparent sharpness of image by increases the contrast around edges. Dark patches near lighter areas get darker, and light patches near dark areas get lighter.

Filter SettingsRadius: The radius of the blur before the filtering. Where a value very low (0.1) will get similar effects as the standard sharpening filter, setting this higher removes noise and increases the contrast of the sharpening. Setting the blur radius too high, however, will have an effect similar to the Posterize tool. Amount: The amount of sharpening to apply to the image. A useful value other than the default is 0.35, where it's usually not enough to produce a significant aura on edges. Threshold: Helpful when the picture you are working with is very noisy. To avoid sharpening of noise in the image you can set the threshold level higher.

Image before sharpening

Fractal ExplorerFractal explorer should be located in your scripts menu at the top of your image window. This tool may not be installed in your copy of The GIMP, but can be acquired by either installing the newest version, or installing the script separately.The exaggerated effect of the unsharp mask filter. Radius: 8, Amount: 2, Threshold 0, Zoom 400%

The Fractal Explorer window allow you to render a fractal from a list. You can change the perspective, zoom, colors, and color depth to customize your fractal from the original defaults.

GIMP/Print version By itself, it can be used to create some very impressive designs, but combined with other tools and filters, very complex patterns can be made.

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Assemble ImagesTo assemble two (or more) images, simply create a new, transparent image of the required size, then open the images you want to add as layers and arrange them as desired.

Result and example imagesIn this tutorial, we will create an image that look like this:

We use http:/ / commons. wikimedia. org/ wiki/ File:Dinosaur_comic_left. png and http:/ / commons. wikimedia. org/ wiki/ File:Dinosaur_comic_right. png as sources for the image, so the tutorial will assume that they can be opened by GIMP.

Creating the canvasFirst, we create an empty image where we can arrange the other images as needed. For this purpose we use the File > New... menu entry. Since the original images are both 124139 pixels big, we make the new image 248139 pixels large. Since we don't want to assume anything about the images' colors, we choose to fill the new image with transparency only. Your image window should now look more or less as displayed on the right.

Importing the imagesThe New Image dialog

To import the images, simply open them as layers (File > Open as Layers...). You should now have the opened images as layers somewhere on the main canvas, possibly hiding under each other. In any case, the layers dialog should show them all. Of course you could also add image data with Copy&Paste. First copy whatever you want and then paste it with Edit > Paste As > New Layer.

This is how your GIMP image window should look like now

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File > Open as Layers...

Only one dinosaur head is visible, the other one is hidden below.

All the needed images are shown in the layers dialog.

Arrange layersNow the only thing left to do is to arrange the layers as needed. For this we use the move tool to move them around until they fit nicely. The result should look more or less as the image below:

Finished! Now you just need to save the image.

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Body ShiftingThis is more or less how magazines are manipulating their images so that the models look "perfect" in their eyes and other areas. A nice example of this in Adobe Photoshop is available at [2]. I strongly recommend using the latest version of The GIMP. Load an image that you want to manipulate. Go in Filters > Distorts > IWarp (for Adobe Photoshop and Photoshop Elements users, this is the equivalent of the "Liquify" filter). You manipulate the image in the preview. In the "Deform Mode" section, choose "Move", this will deform the image in the direction of the movement of the mouse. For the purpose of body shifting, "Remove", "Grow" and "Shrink" are the other interesting buttons. They do what it says on the tin. Adjust "Deform radius" and "Deform amount" to your likings, depending how subtle your edits have to be. Also the "Swirl" options produce interesting results. If you want to start over (e.g. you messed your image up) click on "Reset".

Create a Brushed Metal EffectThis article will describe you how to create a brushed metal effect.

The Hurl filter can be found by going to Filters > Noise > Hurl.

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Step 1First, we fill the canvas using the hurl filter (Filters > Noise > Hurl). Set Randomization (%) to 100. This will do the same thing as the Scatter RGB filter (Filters > Noise > Scatter RGB) with all channels (Red, Green, and Blue) set to 1.0, However, Scatter RGB has slightly more options, and if you turn off Independent RGB in the settings dialogue, may allow you to skip the desaturation step.

Step 2Then, apply a motion blur to the image (Filters > Blur > Motion Blur...) with an angle of 0 and a length of about 50. Change the angle to 180 and repeat the effect. Why? Notice how the right edge of the final image isn't nice and brushed looking? Doing it in both directions will smooth this out. You may have to adjust the length setting so as not to "overblur".

Effect of first step.

Alternatively, you can use the Gaussian Blur filter (Filters > Blur > Gaussian Blur). Just click the chain icon and turn the vertical value down and adjust the horizontal value until you are satisfied. This effect will not leave a side of the image left unblurred and may have an even more satisfying final result with proper adjustment.

Step 3This is the shortest step. Now we only need to desaturate the image. Go to Colours > Desaturate and press Lightness, although Luminosity may sometimes look better.The Motion Blur filter can be found by going to Filters > Blur > Motion Blur.

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Effect of second step.

Apply cropping / tiling / brightness / lighting filters to suit. Cropping may not be necessary if you've used the Gaussian Blur approach as opposed to the Motion Blur approach.

Create a BalloonStep I First, create a square image, and fill it with the colour of the balloon. Next, use the text tool to add any writing. This should be centred, and take up no more than about one-third of the space in each dimension. Merge the text layer with the colour layer.

Effect of third step.

Step II Use "Map to Object" ( Filters > Map > Map Object) to create a sphere. Ensure a transparent background is selected. By default, the sphere won't take up the whole of the image, so tweak this with the Orientation controls.

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Step III To get the shape of a balloon, use Curve Bend ( Filters > Distorts > Curve Bend). Select to work on the lower curve, as a smooth. Add one control point in the lower half of the grid, centred horizontally.

Step IV The resulting image won't fit the current size, so select Image > Fit Canvas to Layers.

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Create a Stone TextureThis tutorial describes the creation of stone textures. 1: We start with Solid Noise ( Filters > Render > Clouds > Solid Noise). Remember to tick the Tileable check box. You can modify this a bit, but its effect may appear negative in the final result. You will see a rather smooth texture.

If you plan to make your image seamless, perhaps for usage in a 3D application, you might want to do a Gaussian Blur ( Filters > Blur > Gaussian Blur) at 100 to make the texture more neutral.

--> 2: Now you have to add some stony grit on it. This can be done with Scatter RGB ( Filters > Noise > Scatter RGB) with Independent RGB off and the values very low (Recommended around 0.05 per channel) 3: Create a New Layer using the New Layer button on the layer window (If you don't have one, in The Gimp's main window, go to File > Dialogs > Create New Doc > Layers, Channels, and Paths.) and

GIMP/Print version do the Plasma filter ( Filter > Render > Clouds > Plasma). Try to get a good balance of black and white. Don't forget to set the Mode in the layer window to "Value" (not "Normal").

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Moving the turbulence up just a little can also help if your aiming to make the texture seamless.

4: Now you have to use Lighting Effects ( Filters > Light Effects > Lighting Effects), go to the bump map tab and choose the layer with the rendered Plasma. Place the light source as desired. Let the plug-in do the rest.

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If you need to make your texture seamless, you probably want to do a Bump map instead, which has the same lighting for all pixels.

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Add Speech Bubbles to a Comic StripThis tutorial will show you how to add text and speech bubbles to pre-made art in The GIMP v2.0 or later.

Getting startedMake a copyThis step isn't strictly necessary, but it's a good idea that could save you from repeating steps if something goes horribly wrong. It's a very good idea if you're working on the only copy of your source image. (Better yet, don't work on the only copy of your source image.)

When you open an image in The GIMP, it automatically becomes the background layer. Anything added to the image will be added as a higher layer, sitting above the background layer. You can combine layers by clicking Layers > Merge Down, and you'll probably want to at some stage, so you can work on multiple added items at the same time. Right-click the Background layer and select Duplicate'. That way, if you accidentally merge the wrong layer down onto a lower one, or perform an operation that seems like a good idea but isn't (and can't be rolled back), you haven't overwritten the only copy of the art you have.

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Add a filterYou'll most likely be adding text in black. If the background is dark as well, the text will be almost invisible and difficult to work with. You can make it easier to view dark text on a dark background by adding a semi-opaque layer between them in a light colour. To do this: Click Layers > New Layer and select a transparent background.

To add the filter, select the Fill tool and select white as the colour to use. Reduce the opacity to 50% and click anywhere on the new layer. You'll see the image turn milky, because you're now viewing the background image through a semi-transparent white layer. Any text you lay down on top of this will be easy to see, and after you've added the speech bubbles around it, the filter can be removed, leaving the background looking like it did to begin with.

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TextAdding the textTo select the Text tool, press T. Select the colour, font and size you prefer. Use anti-alias should be ticked. Jagged edges on your text will make it harder to read, especially if the image is resized. Centre-aligned text is often best, too.

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PositioningAfter the text box is closed, the text tool automatically changes to the Move tool. At this point, if you try to move the text, you'll see it slide out of the box and vanish completely off the edges of the layer. Since you probably do want to move the text, to get it positioned just right, you'll want to expand the layer to the full size of the image. To do this: Click Layer > Layer to Image Size.

Now you can select your text with the Rectangular selection tool. As soon as the mouse is released, the selection tool changes to the Move tool and you can simply drag your text to where it needs to be.

Combining stylesThe GIMP text tool applies a single style to an entire block of text, so an example of what you can't do is bold or italicise individual words. (In other words, the previous sentence would be impossible.) To mix styles, add all the text of one style in a single layer, taking care to leave the space for the other styled text, then add a second text layer written in the second style, positioning it over the first.

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BubblesBackgroundOnce you have all the necessary text on the screen and in the right position, you can create the bubbles. First, add a new layer, below the text layer. This part of the process will involve painting out a section of the current layer, so if it's the same layer your text is on, you'll lose it.

Next, change to the Elliptical selection tool. Once again, make sure to anti-alias. Draw an oval around the text, making sure to leave enough white space so the text isn't crowded. This will become the bubble.

To add a stalk pointing to a character, change to the Path tool. (The GIMP's Path tool mirrors the Photoshop Bzier Curve tool.) This allows you to mark out an area to be added to the selection you made with the Ellipse tool.

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First, click and release the mouse on a starting point just inside the oval. Next, click where you want the point of the stalk to be. If you want a straight line, release and continue to the next step. If you prefer a curve, hold the mouse button down and drag the pointer away from the second point. The line will deform into a curve. It'll take a bit of experimentation to get it exactly where you want it, but it's a nice effect.

Click back into the oval to complete the other side of the stalk. Now you have an oval around the text, and on top of that, a stalk. Move back to the dialogues window again, and click the Paths tab. Right-click the uppermost path on the stack and select Add to selection.

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Now the entire speech bubble including the stalk will have the blinking dashed line around it.

At this stage, you can experiment a little bit to add some variety among the different speech bubble shapes you have. For instance, the script-fu menu's selection options offers the distress selection tool, which will make the outline a bit more random. Finally, select an appropriate background colour (white is the classic) and then the Fill tool again. (Make sure you raise the opacity back to 100% unless you prefer the speech bubble to be semi-transparent on top of your background image.) Click inside the selection and it will fill with the selected background colour out to the edges. Your text should now be invisible behind the background colour. Don't try working with the text or any other task yet, because you still need the speech bubble selected.

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BorderNow that you have the speech bubble filled, you can add a black (or any other colour) border to it. To do this, first select a foreground colour and then: Click Edit > Stroke selection....

The default line thickness is 6 pixels, which is probably too thick. 1px or 2px should be plenty. Click to confirm, and a border in the selected foreground colour will appear around the speech bubble. In order to create a smoother border, first click Select > To Path. Then, click Edit > Stroke Path.... Proceed as stated in the previous paragraph.

Cleaning upText in bubbleNow that you have speech bubbles, you want the text in them. To accomplish this, go back to the layers window. There's probably a whole range of layers by now, since each block of text and each speech bubble you created added one (or more) new layer. Use the mouse to drag the speech bubble layers below the text layers and you'll see the words appear in the bubbles.

Removing the filterUsing the mouse on the layers window, select the semi-opaque layer you created. Right-click and select Delete. You'll see the background image snap back to its original colours behind your speech bubbles.

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Saving your workIf you want to keep the different elements of the image on the separate layers, you'll need to save the image as a .xcf file, which is The GIMP's native file format. To save it in a format you can view in a browser or slideshow program, select the appropriate extension when you save the image and confirm that the file should be exported, (losing the separation between layers in the process).

General practicesWe naturally start reading at the top left-hand corner of a box and proceed towards the bottom right. The first words spoken should be higher and further towards the left unless you have some other way in addition to speech bubble stalks of making it clear which character is speaking. Dark text on a light background is easiest to read. Text and background should never have the same brightness even if they're different colours, since it makes it harder for the eye to distinguish between them. and in general the text should have the 'richer' colour (e.g. red, blue, green) and the background should be a 'washed-out' colour (e.g. white, grey, pale blue). Start big. It's easy to scale large images down, small images scaled up will tend to be pixelated and won't look as good. Don't crowd your images with too much talk. Text should give way to art rather than vice versa.

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Adding thought bubblesSo far a very effective way of adding speech to your work has been showcased. Now it's time to get thinking!

Tailoring the text to your preferencesA quick note on tool-usage that seems to pass people by:

You must open the Tool Option dialogue and use it as above to get the best out of GIMP. In this case the text editor is selected, but you also need it to use all GIMP tools effectively. It is important in the next section.

Creating the BubbleNow what you must do is select the tool options as in the screenshot above. This is essential if you want to follow the rest of this tutorial as you will be using it a lot to make sure everything is working correctly. In this instance the Text tool is selected so you can work on all the options such as the font and text size as well as the text justification. This is essential. Now you need to type in your text as for the speech bubble tutorial. So far all is the same. Note: I have used the same sort of filter as in the earlier tutorial.

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Time to add the selections for the bubble. As before select the elliptical marquee tool.

However, this time you need to select the option in the screenshot above from the Tool Options dialogue. This will allow you to draw the several ellipses necessary to create a thought bubble without cancelling the selection each time you click away from it. After this just fill and stroke as for speech bubbles, move stuff around to your satisfaction, remember to delete the filter and - one thought bubble!

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Blending ExposuresDigital Cameras are limited in their abilities to capture scenes with a large dynamic range. They are especially prone to blown out highlights, losing all detail in bright areas. This How to will demonstrate a method for capturing pictures and then processing them with the gimp to create a picture with more dynamic range that a normal picture. This will involve taking the picture and then combining them back into one picture using the gimp.

Auto Exposure BracketingWe will use Auto Exposure Bracketing to create 3 differently exposed pictures. The first picture will be a normal exposure, the second one will be an underexposure containing the highlights, and the third one will be an overexposed picture containing the shadows. You will need a tripod or another stable surface. It is very important that the camera does not move a single nanometre during the 3 exposures. Compose the frame in the viewfinder, then activate auto exposure bracketing. Then take the 3 pictures without moving the camera in between shots, preferable with a remote to avoid pressing the shutter button.

GIMP/Print version The results should look like this:

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Editing With The GimpOpen the middle exposure picture. From the File menu, select Open as Layers (default shortcut Ctrl+Alt+O) and shift-click to select both the dark and the bright exposure variants of the picture. This will add two layers, which you might want to rename to "light" and "dark" for example. My images aren't perfectly aligned. Not sure why, maybe it has something to do with my tripod being on soft ground. Show only the underexposed and regular layer, and set the underexposed layer to partial transparency. Then zoom to 800% and move the underexposed layer until it is aligned with the regular exposure. Tap the arrow keys to move the layer one pixel at a time. You can try temporarily setting the mode of the dark layer to Divide or Difference; this will give strong contrast at unaligned edges (a high opacity will make the effect stronger). Repeat on the overexposed layer.

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Now duplicate the background layer.

Now use the threshold tool on the duplicated layer to make the overexposed areas pure white ( Tools>Color Tools>Threshold...).

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Add a layer mask to the underexposed layer. Cut the threshold that you just created and paste it onto the layer mask. (The layer mask is the rectangle in the layer dialogue to the right of the layer thumbnail.) With only the underexposed layer and regular layer, it should look like this:

The image looks rough at this point. To fix this select the layer mask and apply a Gaussian blur to it. I used a radius of 50px. The needed strength of the Gaussian blur will depend on the image so experiment with this value. This will

GIMP/Print version ease the transition between the 2 images. It should now look like this:

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Repeat with the overexposed image. The final image should look like this:

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Installing PluginsPlugins can be very helpful in The GIMP. GIMP Plugins can be quite useful. Take, for example, the DDS plugin. The DDS plugin is a now stable and reliable plugin to load DDS files, supporting the OpenGL S3TC extension. Of course, GIMP plugins are not limited to file loading. There exists a GIMP plugin for using the CMYK color model! If you want to run Photoshop plugins in The GIMP, Microsoft Windows and Linux users may use the PSPI plugin. http://www.gimp.org/~tml/gimp/win32/pspi.html

Finding and downloading pluginsThe largest known source of GIMP plugins is the GIMP Plug-In Registry. The GIMP Plug-In Registry contains many useful plugins for The GIMP and all of its versions. In addition to regular plugins, you can also find Perl, Script-Fu and Python plugins at the GIMP Plug-In Registry. You can find the GIMP Plug-In registry at the URL below. http://registry.gimp.org/ Once you have downloaded the plugin, you need to load it into GIMP. In order to load it into GIMP, it needs to be extracted from the package in which it came.

Extracting plugin packagesAlmost every plugin you download will come in a package. You need to extract this package. ZIP files can be extracted easily in Windows and GNU/Linux with the utilities included with your OS. Windows includes ZIP support by default. Most (if not all) GNU/Linux distributions include Info-ZIP [3], which can be used to decompress ZIP files, along with a GUI frontend, such as File Roller for GNOME and Ark for KDE. RAR files are compressed using a proprietary format. WinRAR [4] is the original tool for RAR, available for many platforms, but it is proprietary shareware. There are alternatives. The free software (as in freedom) unrar [5] can unpack RAR files that do not use RAR 3.0 or later. If RAR 3.0 is needed, taking a newer CVS snapshot may work, which has been done for the unrar-free Debian and Ubuntu packages. The 7-Zip [6] program includes support for RAR 3.0, but the RAR component is proprietary. TAR.GZ and TAR.BZ2 files are compressed archives originating from GNU/Linux. It is a double extension. The "GZ" or "BZ2" section refers to the fact the compression method is gzip or bzip2. gzip and bzip2 can only compress single files, however, so a program like tar is used to merge the files/folders into one file, hence the "TAR" section of the name. On GNU/Linux, the original tools can be used, usually "tar -xvzf file.tar.gz" (TAR.GZ) or "tar -xvjf file.tar.bz2" (TAR.BZ2). On Windows, the free 7-Zip can be used. 7z files can be done in Windows with 7-Zip, and in GNU/Linux, if the p7zip utility is installed, Ark and File Roller will work, along with the p7zip command directly. If you find any other file types, a quick search on the internet will help. On the Windows platform, 7-Zip [6] is a piece of software that will extract most file formats, while on GNU/Linux, most free are bundled with the OS and others usually can be found in your package manager.

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Copying the plugin to the GIMP plugin directoryOpen up the folder containing the plugin. Now, copy the files to the clipboard (Select the files, right click one and press copy)

WindowsOn Windows, go to folder GIMP is installed in (usually somewhere in Program Files). Once in the GIMP's main folder navigate to lib\gimp\*version*\ where as *version* represents the version of The Gimp. Then double click the "plug-ins" folder. Not all plugins will run in Windows if the OS is 64bit, "normalmap" is one. To install a script (ends in ".scm") navigate to share\gimp\*version*\. Then double click the "scripts" folder.

GNU/LinuxOn GNU/Linux, you might need to read the manual at the official site first under the section: "1.3. Installing New Plugins" http://docs.gimp.org/en/gimp-scripting.html#gimp-plugins-install Plugins may be stored in different locations depending upon your distribution. Locally installing plugins are easiest because they will usually be stored in a hidden folder under $HOME/.gimp-*.* (where you should replace $HOME with path to your home catalogue and gimp-*.* with the version you use (for example 2.6). In this case, however, the plugins you install will only be available to the user who installed them, which may not be what you want. If you want to install plugins globally, you might have to look around a bit more. Some boxes will have plugins stored at /opt/gnome/lib/gimp/2.0/plug-ins/ (change lib to lib64 if you've got a 64bit OS), others /usr/lib/gimp/2.0/plug-ins/ (change lib to lib64 if you've got a 64bit OS. Running "$whereis gimp" (or "which gimp") in a terminal might help. For example, if the output was /some/place/bin/gimp, then you could check the /some/place/lib (or lib64 if you've got a 64bit OS). In Ubuntu, plugins are located at /usr/share/gimp/2.0/ for both 32 and 64bit. Note that you have to be root to access these files.

Ubuntu LinuxSteps to install GIMP scripts / plugins 1. Download the relevant GIMP script from the GIMP plug-in registry. Each GIMP script is available in two formats namely Script-Fu (.scm) and Python script (.py). You can choose to download either one of them but not both. If you are downloading the Script Fu file, then it should be saved in GIMP scripts folder. If you are downloading the Python file, it should be saved in the GIMP plug-ins folder. Lets assume we have downloaded the python script for the sake of this example. 2. Save the downloaded python script into the GIMP plug-ins folder. In Ubuntu, it is in the directory /usr/lib/gimp/2.0/plug-ins/ How did I find the correct directory, you ask? I opened a terminal and ran the following command : $ dpkg -L gimp | grep plug-ins Of course, there is another way of finding the GIMP plug-ins folder which is, start GIMP and open GIMP Preferences dialog. In this dialog, click on Folders > Plug-ins and you will find the directory where GIMP installs all its plug-ins. Now you copy the downloaded script (gimp-script.py) into this folder as follows : $ sudo cp gimp-script.py /usr/lib/gimp/2.0/plug-ins/. 3. Next open the terminal and set the execute bit for the python script file as follows :

GIMP/Print version $ sudo chmod +x /usr/lib/gimp/2.0/plug-ins/gimp-script.py 4. Lastly, if you have GIMP already running, restart it so that it is aware of all the new scripts you have installed.

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Testing the pluginTo test the plugin, simply open the GIMP and try the plugin. If this plugin makes a certain image type

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