Digital image editing
From ArticleWorld
Digital image editing refers to the process of manipulating images stored in digital formats using special software programs known as graphics editors.
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Working
A bitmap image in a computer’s storage consists of a huge number of pixels. These pixels store information about the colour and brightness of the image. Graphics editors which edit images by manipulating their pixels – either individually or in groups – are known as bitmap image editors. These are more popular than vector based ones (like Adobe Illustrator), which manipulate vector graphics.
Image editors
Image editing programs range from simple to highly sophisticated ones. Simple ones like Microsoft Paint have basic functions like skewing, stretching and resizing. Advanced editors like PaintShop Pro and Adobe Photoshop have extremely powerful algorithms built in them, allowing for greater manipulation and control. They also support more file formats.
Compression of images
Digital images on computers and other media are often compressed in order to reduce file size and hence save storage space. Compression formats can be lossy or lossless, depending on whether image information is lost or not due to the compression. The JPEG format, which is lossy, uses special algorithms that aim to compress images in such a way that the loss of information is not easily noticeable by the human eye. The PNG format is a lossless compression format, and is expected to replace the GIF format in the future.
Image editor features
The following is a list of capabilities supported by most digital image editors:
- Image scaling: Large images are often scaled down for use on the internet. Advanced editors feature linear and cubic interpolation to prevent distortion during image enlargement.
- Cropping: Cropping is used to cut off parts of an image in order to improve its composition or remove unwanted portions.
- Image flipping/rotation: Image editors allow the user to alter the image by inverting or rotating it by a desired amount.
- Other features: Other features include image merging, addition of special effects, changing brightness and contrast, colour alterations and other enhancements.