What is the coding of information and its processing?

In the world there is a constant exchange of information flows. Sources can be people, technical devices, various things, objects of inanimate and living nature. You can receive information as one object, or several.
For better data exchange, the encoding and processing of information on the transmitter side is simultaneously performed (data preparation and conversion into a form convenient for translation, processing and storage), forwarding and decoding on the receiver side (converting the encoded data to the original form). These are interrelated tasks: the source and the receiver must have similar algorithms for processing information, otherwise the encoding-decoding process will be impossible. Coding and processing of graphic and multimedia information are usually realized on the basis of computer technology.

Encoding information on the computer

There are many ways to process data (texts, numbers, graphics, video, sound) using a computer. All the information processed by the computer is represented in binary code - with the help of digits 1 and 0, called bits. Technically, this method is very simple: 1 - the electrical signal is present, 0 - is absent. From the human point of view, such codes are inconvenient for perception - long lines of zeros and ones representing coded symbols are very difficult to decipher immediately. But this format of recording immediately demonstrates what is the coding of information. For example, the number 8 in the binary eight-bit form looks like the following sequence of bits: 000001000. But what's hard for a person, just a computer. Electronics is easier to handle a lot of simple elements than a small number of complex ones.

Coding texts

When we press the button on the keyboard, the computer receives a certain code of the pressed button, looks for it in the standard ASCII character table (American code for information exchange), "understands" which button is pressed and passes this code for further processing (for example, to display the symbol on the monitor ). To store the character code in binary form, 8 digits are used, so the maximum number of combinations is 256. The first 128 characters are used for control characters, numbers and Latin letters. The second half is for national symbols and pseudographics.

Coding texts

It will be easier to understand what is the coding of information, for example. Consider the codes of the English symbol "C" and the Russian letter "C". Note that the symbols are capitalized, and their codes are different from lowercase. English character will look like 01000010, and Russian - 11010001. The fact that for a person on the monitor screen looks the same, the computer perceives quite differently. It is also necessary to pay attention to the fact that the codes of the first 128 characters remain unchanged, and starting from 129 onwards, different letters may correspond to one binary code, depending on the code table used. For example, decimal code 194 can correspond in KOI8 to the letter "b", in CP1251 - "B", to ISO - "T", and in the encodings of CP866 and Mac in general there is no symbol corresponding to this code. Therefore, when we open the text instead of Russian words, we see an alphabetic symbolic abracadabra, which means that this encoding of information does not suit us and we need to choose another symbol converter.

Coding numbers

In the binary system of calculation, only two variants of the value-0 and 1 are taken. All basic operations with binary numbers are used by science called binary arithmetic. These actions have their own peculiarities. Take, for example, the number 45, typed on the keyboard. Each digit has its own 8-bit code in the ASCII code table, so the number takes two bytes (16 bits): 5 - 01010011, 4 - 01000011. In order to use this number in calculations, it is translated by special algorithms into the binary system of the calculus in the form of an eight-digit binary number: 45 - 00101101.

Coding and processing of graphic information

In the 1950s, computers that were most often used for scientific and military purposes were first implemented graphically. Today, visualization of information received from a computer is common and customary for any person phenomenon, and in those days it produced an extraordinary revolution in the work with technology. Perhaps, the impact of the human psyche affected: visual information is better absorbed and perceived. A major breakthrough in the development of data visualization occurred in the 1980s, when the coding and processing of graphic information received a powerful development.

Analog and discrete graphics representation

Graphic information can be of two types: analog (a painting canvas with continuously changing color) and discrete (a picture consisting of a set of points of different colors). For the convenience of working with images on a computer, they are subjected to processing - spatial sampling, in which each element is assigned a specific color value in the form of an individual code. Coding and processing of graphic information is similar to working with a mosaic consisting of a large number of small fragments. And the quality of coding depends on the size of the points (the smaller the size of the element - the points will be larger by the unit of area, - the higher the quality) and the size of the palette of the colors used (the more color states each point can take, respectively, carrying more information, the better the quality ).

Creating and storing graphics

There are several basic image formats - vector, fractal and raster. Separately, the combination of raster and vector is considered - a widely used multimedia 3D-graphics in our time, representing methods and methods for constructing three-dimensional objects in virtual space. Coding and processing of graphic and multimedia information is different for each image format.

Raster image

The essence of this graphic format is that the picture is divided into small colored dots (pixels). The upper left control point. Encoding of graphic information always starts from the left corner of the image line by line, each pixel receives a color code. The volume of the raster image can be calculated by multiplying the number of points by the information volume of each of them (which depends on the number of color options). The higher the resolution of the monitor, the more the number of raster rows and dots in each line, respectively, the higher the image quality. To process raster-type graphic data, you can use binary code, since the brightness of each point and the coordinates of its location can be represented as integers.

Vector Image

Coding of graphic and multimedia information of vector type is reduced to the fact that the graphic object is represented in the form of elementary segments and arcs. The properties of the line that is the base object are the shape (straight or curve), color, thickness, outline (dashed or solid line). Those lines that are closed have one more property - filling with other objects or color. The position of the object is determined by the points of the beginning and end of the line and the radius of curvature of the arc. The volume of graphic information of a vector format is much smaller than a bitmap, but requires special programs for viewing graphics of this type. There are also programs - vectorizers that convert raster images into vector images .

Fractal graphics

This type of graphics, like vector, is based on mathematical calculations, but its basic component is the formula itself. In the computer memory, there is no need to store any images or objects, the picture itself is drawn only by the formula. This type of graphics is convenient to visualize not only simple regular structures, but also complex illustrations simulating, for example, landscapes in games or emulators.

Sound waves

What is the coding of information, you can still demonstrate the example of working with sound. We know that our world is full of sounds. Since ancient times, people have figured out how sounds are born - waves of compressed and rarefied air, affecting the eardrums. A person can perceive waves with a frequency of 16 Hz to 20 kHz (1 Hz - one oscillation per second). All waves whose oscillation frequencies fall within this range are called sound waves.

Sound properties

The characteristics of the sound are the tone, the timbre (the color of the sound depending on the shape of the oscillations), the height (frequency, which is determined by the oscillation frequency per second) and the volume, depending on the intensity of the oscillations. Any real sound consists of a mixture of harmonic oscillations with a fixed set of frequencies. The oscillation with the lowest frequency is called the basic tone, the others are the overtones. A special color tone is given by a timbre - a different number of overtones inherent to this particular sound. It is by the timbre that we can recognize the voices of close people, distinguish the sound of musical instruments.

Programs for working with sound

Conditionally, programs on the functional can be divided into several types: utility programs and drivers for sound cards that work with them at a low level, audio editors that perform various operations with audio files and apply various effects to them, software synthesizers and analog-to-digital converters ADC) and digital-to-analog (DAC).

Audio encoding

Encoding multimedia information consists in converting the analog nature of sound into a discrete one for more convenient processing. The ADC receives an analog signal at the input , measures its amplitude at certain time intervals, and outputs a digital sequence with the data on the amplitude changes. There are no physical transformations.

The output signal is discrete, therefore, the more often the amplitude measurement frequency (sample), the more accurate the output signal corresponds to the input, the better the encoding and processing of multimedia information. A sample is also referred to as an ordered sequence of digital data acquired through an ADC. The process itself is called sampling, in Russian - sampling.

The reverse conversion is performed by means of a DAC: on the basis of the digital data arriving at the input, an electric signal of the necessary amplitude is generated at certain instants of time.

Sample parameters

The main parameters of the sampling are not only the measurement frequency, but also the bit depth - the accuracy of measuring the amplitude change for each sample. The more accurately the value of the amplitude of the signal is transferred to each unit of time during digitization, the higher the quality of the signal after the ADC, the higher the reliability of the wave reconstruction in the reverse transformation.