DIGITALIZATION

The term digitization is often used when diverse forms of information, such as text, sound, image or voice, are converted into a single binary code. Digital information exists as one of two digits, either 0 or 1. These are known as bits (a contraction of binary digits) and the sequences of 0s and 1s that constitute information are called bytes.^[3]

Analog signals are continuously variable, both in the number of possible values of the signal at a given time, as well as in the number of points in the signal in a given period of time. However, digital signals are discrete in both of those respects – generally a finite sequence of integers – therefore a digitization can, in practical terms, only ever be anapproximation of the signal it represents.

Digitization occurs in two parts:

Discretization

The reading of an analog signal A, and, at regular time intervals (frequency), sampling the value of the signal at the point. Each such reading is called a sample and may be considered to have infinite precision at this stage;

Quantization

Samples are rounded to a fixed set of numbers (such as integers), a process known as quantization.

In general, these can occur at the same time, though they are conceptually distinct.

A series of digital integers can be transformed into an analog output that approximates the original analog signal. Such a transformation is called a DA conversion. The sampling rate and the number of bits used to represent the integers combine to determine how close such an approximation to the analog signal a digitization will be.

Examples[edit]

The term is often used to describe the scanning of analog sources (such as printed photos or taped videos) into computers for editing, but it also can refer to audio (where sampling rate is often measured in kilohertz) and texture map transformations. In this last case, as in normal photos, sampling rate refers to the resolution of the image, often measured in pixels per inch.

Digitizing is the primary way of storing images in a form suitable for transmission and computer processing, whether scanned from two-dimensional analog originals or captured using an image sensor-equipped device such as a digital camera, tomographical instrument such as a CAT scanner, or acquiring precise dimensions from a real-world object, such as a car, using a 3D scanning device.^[4]

Digitizing is central to making a digital representations of geographical features, using raster or vector images, in a geographic information system, i.e., the creation of electronic maps, either from various geographical and satellite imaging (raster) or by digitizing traditional paper maps or graphs^[5][6] (vector).

"Digitization" is also used to describe the process of populating databases with files or data. While this usage is technically inaccurate, it originates with the previously proper use of the term to describe that part of the process involving digitization of analog sources, such as printed pictures and brochures, before uploading to target databases.

Digitizing may also used in the field of apparel, where an image may be recreated with the help of embroidery digitizing software tools and saved as embroidery machine code. This machine code is fed into an embroidery machine and applied to the fabric. The most supported format is DST file. Apparel companies also digitize clothing patterns^{[citation needed]}

Analog signals to digital[edit]

Analog signals are continuous electrical signals; digital signals are non-continuous. Analog signal can be converted to digital signal by ADC.^[7]

Nearly all recorded music has been digitized. About 12 percent of the 500,000+ movies listed on the Internet Movie Database are digitized on DVD.^{[citation needed]}

Handling of analog signal becomes easy ^{[according to whom?]} when it is digitized because the signal is digitized before modulation and transmission. The conversion process of analog to digital consists of two processes: sampling and quantizing.

Digitization of personal multimedia such as home movies, slides, and photographs is a popular method of preserving and sharing older repositories. Slides and photographs may be scanned using an image scanner, but videos are more difficult.^[8]