Scanner Technology: Features and Image Processing

The scanner is a computer input device that allows you to scan images or documents using Optical Character Recognition (OCR). It emits light onto the document being scanned and captures the reflected light using a photosensor.

Types of Software

• OCR (Optical Character Recognition): Software specializing in extracting text characters from scanned document images, converting them into editable text.
• OMR (Optical Mark Recognition): Software designed to extract marks from documents, storing them as database fields.

Transmission of Photographs

• Wired: Traditional cable connections.
• Card Reader: For transferring data from memory cards.
• Infrared: Transmits and receives waves in the infrared spectrum. Requires devices to be side-by-side for communication (2-5m range), not ideal for large networks.
• Bluetooth: Transmits voice and data between devices using short-range radio frequency. Requires password permission (15-20m range).
• Wireless: Utilizes low-power radio waves in a free-use band for broadcasting (50-100m range).

Image Properties

• Color Depth: The number of bits used to store color information for each pixel. A pixel is composed of three sub-pixels, one for each primary color.
• Image Resolution: The parameter relating the number of pixels to the viewing dimensions.
• Image Size: A digital image consists of millions of cells organized in a grid. The image size is determined by the dimensions of this grid.

Common Image File Formats

• BMP (Bitmap): Primarily used by Windows.
• GIF (Graphics Interchange Format): Widely used, supports 8-bit color and 256 colors.
• JPEG (Joint Photographic Experts Group): Ideal for large photographic images.
• PNG (Portable Network Graphics): Supports lossless compression, meaning no quality is lost.
• TIFF (Tagged Image File Format): Commonly used in professional graphics printing.

Photo retouching is a technique used to improve the quality of a photograph, either by preserving the original reality or by altering it to suit specific preferences.

Key Photo Editing Concepts

• Tone: Defines the color of an element.
• Brightness: The degree of lightness or darkness of a color.
• Saturation: The purity or intensity of a color.

Graphic Design Elements

• Vector Graphics: Composed of geometric elements such as points, lines (straight or curved), and polygons.
• Form: In graphic design, this encompasses all regular polygons, irregular shapes, or complex compositions that can be created.