There are various image editing tools available on Linux. Many of them are in fact pretty good but there is one that shines out of the rest. The tool that I am talking about is GIMP. It is a powerful image editing tool that can be used for editing professional quality images. GIMP image editor has lots and lots of option which may seem confusing to a beginner. So, In this article we will discuss and explain some basic editing tools of GIMP image editor.
GIMP Image Editor
GIMP is an open source and free-ware program for photo editing and image manipulation which can be used for viewing, editing and enhancing your pictures. This software is loaded with basic to complex image manipulation features which makes it a great program for beginners as well as professionals. Although it has intuitive user interface but it may take you some time to get fully accustomed to this program as it is bundled with features.
User can open unlimited number of images at one time with its tile based memory management. With more than 150 standard filters and effects, GIMP can enhance your pictures like a professional image editor. GIMP is expandable with more than 100 extensions already available in plug-in browser and user can also customize this program according to the requirement. It has advanced capabilities like Perl, Python etc. and it can automate its operations with scripting languages.
GIMP supports multiple file formats for loading, conversion, displaying and saving. GIMP is embedded with advanced features for image manipulation e.g. layers, full alpha channel support etc. but we will focus on its basic painting and image editing part for beginners.
Here is how GIMP image editor looks (with an image opened for editing) :
Basic editing tools
GIMP contains a complete set of painting tools which are required for image editing. For editing, you need to drop an image in GIMP default box and start. You can select your editing tool from toolbox at the right. Toolbox has multiple tools for performing different functions which are described below.
Selection tools are used for selecting a particular area in picture for editing.
Selection tools include:
- Rectangle select tool for selecting a rectangular region.
- Ellipse select tool for selecting an elliptical region.
- Free select tool for selecting a hand-drawn region with free and polygonal segments.
- Fuzzy select tool for selecting a contiguous region on the basis of colour.
- Select by Colour tool for selecting regions with similar colours,
- Scissors select tool for selecting shapes using intelligent edge fitting.
- Foreground select tool for selecting a region containing foreground objects.
For selection tools, see the tool icons marked with RED in the image below.
Paint tools are used for painting specific or selected areas.
Paint tools include:
- Bucket fill tool which is used to fill selected area with a colour or pattern.
- Blend tool which fills selected area with a colour gradient.
- Pencil tool for painting hard edges.
- Paint brush for smooth strokes of paint.
- Eraser tool for erasing.
- Airbrush tool which is used for painting with variable pressure.
- Ink tool for calligraphy.
- Clone tool for cloning purposes.
- Healing tool for healing image irregularities.
- Blur/Sharpen tool for sharpening images.
- Smudge tool to smudge colours on a selection.
- Dodge/burn tool for lightening or darkening the selective area using a brush.
For paint tools, see the tool icons marked with RED in the image below.
Transform tools are used for transforming the picture or the selected area.
Transform tools include :
- Rotate tool for rotating the picture or selected area.
- Move tool for moving the layer or selection.
- Alignment tool for adjusting the alignment of image
- Crop tool for removing edge areas.
- Scale tool for scaling(setting height and width) layers, selections or path
- Shear tool for shifting one part of the image to a direction and other part to opposite direction
- Perspective tool for changing the perspective of layer, selection or path.
- Flip tool for reversing the layer or path horizontally or vertically.
For transform tools, see the tool icons marked with RED in the image below.
These include :
- Colour tools for colour balance, hue-saturation, colourization, posterization, bright-contrast etc.
- Text tool for editing or creating text layer.
- Zoom tool for adjusting zoom layer.
- Paths tool for creating and editing paths.
- Colour picker tool for setting colours from image pixels.
- Measure tool for measuring distances and angles etc.
For more tools, see the tool icons marked with RED in the image below.
How to use these tools
To edit an image, go to the selection tools and select an area that you want to edit. Once you have selected the area, you can select to paint it using paint tools or transform it using transform tools. You can change the colours, levels, zoom the picture, add text and even remove the objects from the picture. For saving the changes, you can select the save option in file or if you don’t want to save the change, go for revert option in file.
In the next article of this series, we will cover advance features/tools of GIMP image editor