Classification of Images

Digital Image editing

Digital image editing refers to the process of manipulating and enhancing images using software tools. It involves making changes to various aspects of an image, such as color, contrast, brightness, composition, and other visual elements.

There are numerous software applications available for digital image editing, ranging from basic to advanced tools. Some popular image editing software include Adobe Photoshop, GIMP, Corel PaintShop Pro, and Pixlr. These applications offer a wide range of features and functionalities to modify and improve images.

Common techniques used in digital image editing include:

Cropping and resizing: Adjusting the size and dimensions of an image by cropping unwanted areas or resizing it to fit specific requirements.

Adjusting exposure and color: Changing the brightness, contrast, saturation, and other color properties of an image to enhance its overall appearance.

Removing imperfections: Removing unwanted objects, blemishes, or distractions from an image using tools like the clone stamp or healing brush.

Retouching and restoring: Enhancing the appearance of subjects in portraits by retouching skin, removing wrinkles, or performing digital makeup. Additionally, restoring old or damaged photographs by repairing scratches, tears, or faded areas.

Adding text and graphic elements: Overlaying text, logos, or graphic elements onto an image for branding, promotional, or informational purposes.

Applying filters and effects: Adding creative filters, effects, or artistic styles to an image to achieve a specific look or mood.

Compositing and collage: Combining multiple images to create a composite or collage artwork.

Digital image editing provides extensive creative possibilities, allowing photographers, graphic designers, artists, and individuals to transform and enhance their images according to their vision or specific requirements.

Basic terms of computer graphics

Pixel- a pixel is the smallest unit of information that represents a single point in an image. The word "pixel" is derived from "picture element." Each pixel corresponds to a tiny square or dot on a computer screen or image sensor.

Pixels are the building blocks of digital images, and they are arranged in a grid-like pattern to form the overall image. Each pixel carries information about its color and intensity. In a color image, each pixel typically consists of three color channels: red, green, and blue (RGB). The combination of these three channels at each pixel determines the overall color of that pixel.

Computer graphics- computer graphics refers to a still image such as drawing or photograph.

Types of Computer graphics- Computer graphics can be divide into two categories

Bitmap graphics (Raster graphics)
Vector graphics.

Difference between Bitmap and Vector graphics

Bitmap and vector graphics are two different types of digital image formats, each with its own characteristics and use cases. Here are the key differences between the two:

Representation of Images:

Bitmap: Bitmap graphics, also known as raster graphics, are composed of a grid of individual pixels. Each pixel contains color and intensity information, and the entire image is made up of a collection of these pixels. When you zoom in on a bitmap image, you can see the individual pixels that make up the image.

Vector: Vector graphics, on the other hand, are represented by mathematical equations that define lines, curves, and shapes. Instead of using pixels, vector graphics use points, lines, and curves to create objects. These objects are stored as mathematical formulas, which allow them to be scaled to any size without losing image quality.

Scalability:

Bitmap: Bitmap images are resolution-dependent, meaning they have a fixed number of pixels. When you resize a bitmap image, you either add or remove pixels, resulting in a loss or gain of detail. Enlarging a bitmap image too much can lead to pixelation, where individual pixels become visible and the image appears blocky.

Vector: Vector graphics, being based on mathematical equations, are resolution-independent. They can be scaled to any size without losing image quality. This makes vector graphics ideal for tasks that require scalability, such as logos, illustrations, and print media.

File Size:

Bitmap: Bitmap images tend to have larger file sizes compared to vector graphics. The file size of a bitmap image increases with the resolution and color depth (number of bits per pixel). Images with higher resolution and more colors require more data to be stored.

Vector: Vector graphics typically have smaller file sizes as they only store mathematical formulas and instructions for rendering objects. This makes vector graphics more suitable for web graphics, where smaller file sizes are desirable for faster loading times.

Editing Capabilities:

Bitmap: Bitmap images are suitable for detailed image editing, such as retouching photos or applying effects. Image editing software like Adobe Photoshop allows manipulation of individual pixels, making precise modifications possible.

Vector: Vector graphics are best for creating and editing shapes, lines, and curves. Editing software like Adobe Illustrator provides tools to manipulate objects, change their colors, adjust their sizes, and modify their shapes. However, vector graphics are not well-suited for editing detailed photo-like images.

Use Cases:

Bitmap: Bitmap graphics are commonly used for photographs, realistic digital images, and complex visual compositions that require precise control over individual pixels. They are suitable for web images, digital artwork, and photo editing.

Vector: Vector graphics are often used for logos, icons, illustrations, typography, and print media. They are ideal for tasks that require scalability, such as designing for different screen sizes, creating high-resolution prints, or generating graphics for mobile applications.

In summary, bitmap graphics are composed of pixels, have fixed resolution, are suitable for detailed image editing, but can suffer from pixelation when scaled. Vector graphics, on the other hand, are based on mathematical formulas, are resolution-independent, have smaller file sizes, are suitable for scalable designs, but are less suitable for detailed photo editing.

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Digital Image Editing