Devices for processing, storing and transmitting digital information. "Digital information processing devices: digital camera" - Lesson

Digital devices

Analog Devices

Analog devices include functional electronic components, designed to perform various operations and conversions on analog signals. Structurally, analog devices can be represented as:

1. Two-terminal

It has 2 pairs of input terminals, to which the signal sources are connected, and the load is connected to the output terminals. It is a transmission link with control parameters.

Digital devices include functional units designed to perform operations on information objects in the form digital signals... Code words are used to represent digital signals. Features: the simplest alphabet is used for construction - two letters, denoted by the symbols 0 and 1. The code word is a number in 2 SS. The number of letters in the codeword is fixed.

A word contains n letters or digits. In digital devices, the object of information is binary numbers, not functions of time.

Principles of functioning of digital devices:

1) To execute the command, a certain time is allotted, for this a clock pulse generator is used, it formulates the control signal

2) After the start of the operation, all input code words are converted to the required output

3) Output code words are sent to storage in the memory of the digital system or in external devices to take action

Ways to handle codewords:

To carry out operations on by code words, it is extremely important that they are in the form electrical signals... A potential way of presenting has gotten widespread. Logical zero matches low level signal (voltage), logical unit - high... Operations on codewords can be performed in two ways: sequentially (bit by bit) and in parallel.

The simplest converters of information:

A computer consists of millions of elements: transistors, diodes, registers that make up integrated circuits... But the study of the work of a PC is facilitated by the regularity of its structure, which means: a computer consists of a large number the simplest elements, there are several types. The elements form a small number of typical circuits.

According to the degree of complexity of the functions performed, they are distinguished:

1) Elements - simplest part that performs operations on individual bits. Distinguish logically (and, or, not, and-not, or-not), memorizing (triggers different types) and auxiliary, serving to amplify and form signals.

2) Nodes - consist of elements and perform operations on words. Distinguish between combinational and cumulative (sequential)

Combinational are built exclusively on logical elements;

Accumulators include logic gates and memory gates;

PC nodes include: registers, counters, adders, multiplexers, etc.

3) Devices - consist of several nodes, perform one or a number of similar operations on machine words. Devices include ALU, memory device, control device, memory device, input / output device.

Digital devices - concept and types. Classification and features of the category "Digital devices" 2017, 2018.

SECTION 2. DIGITAL ELECTRONIC CIRCUITS

Basic concepts of digital electronics

The purpose of electronic devices, as you know, is to receive, transform, transmit and store information in the form of electrical signals. Signals acting in electronic devices, and, accordingly, the devices themselves are divided into two large groups: analog and digital.

Analog signal - a signal that is continuous in level and in time, i.e. such a signal exists at any time and can take any level from the specified range.

Quantized signal - a signal that can only take certain quantized values ​​corresponding to the quantization levels. The distance between two adjacent levels is the quantization step.

Sampled signal a signal, the values ​​of which are set only at the instants of time, called sampling instants. Distance between adjacent sampling points - sampling step
... With constant
the Kotelnikov theorem is applicable:
, where - top cutoff frequency spectrum of the signal.

Digital signal - signal quantized in level and time-sampled. The quantized values ​​of a digital signal are usually encoded with a certain code, with each sample selected during the sampling process replaced by the corresponding codeword, the symbols of which have two values ​​- 0 and 1.

Typical representatives of analog electronics devices are communication devices, radio broadcasting, television. General requirements for analog devices are minimal distortion. The desire to meet these requirements leads to the complication electrical circuits and device designs. Another problem of analog electronics is the achievement of the necessary noise immunity, because in an analog communication channel, noise is fundamentally unavoidable.

Digital signals are formed by electronic circuits, the transistors in which are either closed (the current is close to zero) or completely open (the voltage is close to zero), so they dissipate insignificant power and the reliability of digital devices is higher than analog ones.

Digital devices are more immune to interference than analog ones, since small extraneous disturbances do not cause erroneous operation of devices. Errors appear only in the case of such disturbances in which a low signal level is perceived as high or vice versa. Digital devices can also use special codes to correct errors. There is no such possibility in analog devices.

Digital devices are insensitive to the spread (within acceptable limits) of the parameters and characteristics of transistors and other circuit elements. Unmistakably manufactured digital devices does not need to be tuned, and their characteristics are completely repeatable. All this is very important in the mass production of devices using integrated technology. The cost-effectiveness of the production and operation of digital integrated circuits has led to the fact that in modern radio electronic devices, not only digital, but also analog signals are digitally processed. Digital filters, regulators, multipliers, etc. are widespread. Before digital processing analog signals are converted to digital using analog-to-digital converters (ADC). Reverse transformation - recovery analog signals by digital - performed using digital-to-analog converters (DAC).

With all the variety of tasks solved by digital electronics devices, their functioning occurs in number systems operating with only two digits: zero (0) and one (1). By type of coding binary digits electrical signals, elements of digital technology are divided into potential (static) and impulse (dynamic).

V potential elements zero and one correspond to two sharply different voltage levels. In this case, the voltages can be both positive and negative with respect to the case, the electric potential of which is taken as zero. There are elements that work in positive and negative logic. In elements with positive logic, the transition from 0 to 1 occurs with increasing potential. In negative logic, a more negative voltage is taken as a logical 1.

V impulse elements, a logical unit corresponds to the presence, and a logical zero corresponds to the absence of an impulse.

The operation of digital devices is usually clocked a sufficiently high frequency clock generator. During one clock cycle, the simplest micro-operation is implemented - read, shift, logical command, etc. Information is presented as a digital word. To transfer words, two methods are used - parallel and sequential. Serial coding is used in the exchange of information between digital devices (for example, in computer networks, modem connection). Information processing in digital devices, as a rule, is implemented using parallel information coding, which ensures maximum performance.

The element base for building digital devices is made up of digital integrated circuits (ICs), each of which is implemented using a certain number logical elements(LE) - the simplest digital devices that perform elementary logical operations.

All digital devices can be classified into one of two main classes: combinational (without memory) and sequential (with memory). Combinational are called devices, the state of the outputs of which at any moment in time is uniquely determined by the values ​​of the input variables at the same moment in time. These are logical elements, code converters (including encoders and decoders), code distributors (multiplexers and demultiplexers), code comparators, arithmetic logic devices (adders, subtractors, multipliers, ALU itself), read-only memory (ROM), programmable logic matrices (PLM).

Output state consistent digital device (state machine) in this moment time is determined not only by logical variables at its inputs, but also depends on the order (sequence) of their arrival at the previous moments of time. In other words, finite automata must necessarily contain memory elements that reflect the entire history of the arrival of logical signals, and are executed on triggers, while combinational digital devices can be entirely built only on logical elements. Sequential digital devices include triggers, registers, counters, random access memory (RAM), microprocessor devices (microprocessors and microcontrollers).

Before studying various digital devices, let's get acquainted with the elements of the mathematical apparatus used in their construction. Its constituent parts are the concept of number systems and methods for describing and transforming logical functions.

9. Mathematical foundations of digital electronics

9.1. Positional systems reckoning

Number system is called the way of displaying an arbitrary number by a limited set of characters, called numbers. The position number, which determines the weight with which this digit is added to the number, is called discharge, and number systems with the noted property are positional.

V general case n- positive bit N v arbitrary system radix R is represented by a sum of the form

(9.1)

where a k- individual digits in the number record, the values ​​of which are equal to the members of the natural series in the range from 0 to ( R– 1).

When performing calculations with digital electronic devices, elements with two stable states are used. For this reason, the positional binary number system (with base 2) has become widespread in digital technology. In each binary digit, called bit, can be 1 or 0. The very notation of a number (binary code) is a sequence of ones and zeros. To distinguish a binary number from a decimal number, we will supplement it on the right with the suffix V(Binaire), as is customary in special machine-oriented programming languages ​​called assemblers.

The weights of the adjacent bits of the binary code of the number differ by two times, and the rightmost bit (least significant) has weight 1. Therefore, for example

101101B = 1. 2 5 + 0. 2 4 + 1. 2 3 +1. 2 2 + 0. 2 1 + 1. 2 0 = 45.

The four adjacent bits are called notebook, a group of 8 bits is called byte, and from 16 bits - machine word... The aggregate of 1024 (2 10) bytes is called a kilobyte, of 1024 kilobytes - a megabyte, of 1024 megabytes - a gigabyte.

1 GB = 2 10 MB = 2 20 KB = 2 30 bytes .

Modern personal computers can store in their memory on hard magnetic disks of digital information in the volume of tens of gigabytes.

Arithmetic operations in binary system reckoning is extremely simple and easy to implement in hardware. However, when entering and outputting information into a digital device, it must be represented in a more familiar decimal number system. Striving to simplify the recalculation procedure binary numbers the decimal equivalent led to the use of bcd code. In this code, to write individual digits of the digits of the decimal number, they use the tetrads of their binary

Modern digital devices: touch screens scanners cameras video cameras mobile phones webcams document cameras video projectors devices wireless transmission data cctv systems e-books digital microscopes

Touch screens can be equipped with TVs, computer monitors and other screen gadgets. They can be installed in payment terminals, in equipment for trade automation, in pocket computers, in operator panels in industry.

Scanning Devices A scanner is a device designed to input various color and black and white images(photographs, drawings, slides), and text information from a sheet of paper, from the page of a book or magazine. The scanner is used when there is a need to enter text and / or a graphic image from an existing original into a computer for its further processing (editing, etc.).

Scanner is a device for entering information from paper into computer memory and further editing text or images.

Fields of application of cameras Widely used in the printing industry, scientific research, medicine, geology, forensics. In these and many other industries, it is often necessary to obtain images almost instantly with subsequent processing and sending them to long distances via the Internet.

Webcams - digital cameras, capable of capturing images in real time, which are then transmitted over the Internet or other video application.

Document camera - special video camera... It is used when it is necessary to show something small that exists in one copy (books, pictures, images from a microscope). Connects to TV, projector, computer.

Electronic books are classified as tablet computers... Their appearance is due to the development and specialization of tablet computers in general. Some modern devices equipped touch screen and have an expanded set of functions, and allow not only reading, but also editing text.

Benefits Compact and portable. One device can store hundreds and thousands of books. In addition, the device is usually smaller and lighter than a paper book. Image settings. At the request of the user, you can change the font style and size and the output format (in one column or in two, portrait or landscape). The ability to change the font size makes it possible to read books for people who are not allowed to read by the small, unregulated font of paper books. Additional features. The device can be used for text search, hyperlinks, display of temporary selections and notes, electronic bookmarks, a dictionary.

Benefits Built-in programs - speech synthesizers allow reading texts. The e-book allows not only reading texts, but also displaying animated pictures, multimedia clips or playing audiobooks. The cost of the text. Many texts in in electronic format free or cheaper than paper. Availability. If you have an Internet connection, the texts are available for download at any time from the respective sites (electronic libraries).

Benefits Environmentally friendly. To read texts in an e-book, you do not need paper, for the production of which forests are cut down. Safe for asthmatics, allergy sufferers, house dust and paper dust.

Disadvantages E-readers with TFT screens have an adverse effect on human vision, similar to a computer. Relatively poor image quality, not comparable to paper books published on expensive high quality paper [source unspecified 42 days]. Like any electronic devices reading devices e-books much more sensitive to physical impact(damage) than paper books High price... Some publishers release electronic version books with delay. Some of the books are not officially published as an electronic version at all.

Disadvantages In some models [clarify] DRM is used, which imposes restrictions, including on fair use, so the use of DRM leads to a situation that any book cannot be read on any device. One of the striking examples was the remote deletion of legally purchased books from users' devices. However, since it is not difficult to buy an e-book that reads DRM-free formats (for example, fb 2, rtf, txt, etc.), and communication capabilities not all e-books possess, this can hardly be considered a disadvantage of e-books as a class of devices. Devices for reading e-books require periodic recharging of the built-in rechargeable batteries (batteries).

Digital microscope The digital microscope is a microscope complete with digital system image input that transfers images to a computer. A digital microscope makes it possible not only to observe micro objects, but also to document images using the input system installed on the microscope, and, if necessary, carry out measurements on images and analyze them using software.

Digital microscope To transfer images from a microscope or stereomicroscope to a computer, digital camcorders, digital cameras or analog systems input. With the help of these devices, the image from the microscope is transferred to a computer for subsequent archiving or processing, if necessary. The choice of an input system depends on the tasks to be solved and the requirements for image quality.

Digital microscope Digital microscopes allow you to transfer an image from various magnifications from increasing several times to increasing hundreds of thousands of times

A graphics tablet, or digitizer, is designed for input into a computer graphic images, and is used when working with professional graphics and CAD programs, as well as for creating or copying drawings or photographs. It allows you to create drawings just like on a piece of paper. This input device consists of a tablet and a pointer. The image is converted to digital form, hence the name of the device (from the English digit - number).

Graphic tablet The principle of operation of the digitizer is based on fixing the coordinates of the cursor on the surface of the tablet using a built-in mesh consisting of wire or printed conductors. The device allows you to convert the movement of the pointer on the tablet to the format vector graphics... The digitizer accurately determines the absolute coordinates of the pointer on the tablet and translates them into the coordinates of a point on the monitor screen.

Graphic tablet Special circular cursors and pens are used as pointers. Like mice, pointers are provided with buttons. Cursors allow you to precisely set the coordinates of a point, they are often used when working in CAD. Feathers are used when working in graphic editors, some of them are pressure-sensitive and allow you to change the parameters of the lines

Graphics tablet Tablets are rigid and flexible. Flexible tablets can be rolled up into a tube, they are convenient for transportation and storage, they are lighter, more compact and more expensive, but at the same time they have lower resolution and reliability than rigid ones.

Graphic tablet The result of the digitizer's work is reproduced on the monitor screen and, if necessary, can be printed out on a printer. Digitizers are usually used by architects and designers. The high price of professional digitizers with a large tablet format and a quality, balanced pointer limits the use of this input device

During the development of digital technologies, computers of the most different types... Many of them have long been forgotten, but some have had a strong influence on the development of modern computing systems. Here we will give a brief overview of some of the stages in the development of computers to show how human thought came to the modern understanding of computer technology.

Devices that make it easier to count or memorize its results have been known for a long time, but we will only be interested in computing devices that automatically execute programs embedded in them, therefore we do not consider such devices as counting, mechanical adding machines and electronic calculators.

The first counting machine with a stored program was built by a French scientist Blaise Pascal in 1642. It was mechanical with a hand drive and could perform addition and subtraction operations. German mathematician Gottfried Leibniz in 1672 he built a mechanical machine that could do the same operations of multiplication and division. For the first time a machine working according to the program was developed in 1834 by an English scientist Charles Babbage... It contained a memory device, a computing device, a punched card input device and a printing device. The commands were read from a punched card and performed data reading from memory into a computing device and writing the results of calculations into memory. All devices of Babbage's machine, including memory, were mechanical and contained thousands of gears, the manufacture of which required precision unavailable in the 19th century. The machine implemented any programs written on a punched card, so for the first time a programmer was required to write such programs. The first programmer was an Englishwoman Ada Lovelace, after which the programming language Ada was named in our time.

In the 20th century, electronics began to develop and its capabilities were immediately adopted by the developers of computers. The countdown of generations of digital computers begins with the construction of computers, the basic system of elements of which was built on electronic components. Note that dividing the period of development of digital technology into stages is mainly associated with the translation basic system elements for new technologies for the production of electronic components.

The first generation - vacuum tubes (1945-1955)

The basic system of elements of this generation of computers was based on vacuum tubes. Their use determined both the advantages and disadvantages of digital devices. Electronic tubes provided high speed switching logic elements, which increased the speed of computation in comparison with attempts to create a computer, base element which was built on the basis of an electromechanical relay. Vacuum tubes were durable enough to provide reliable computer operation. Unfortunately, lamp computers also had a lot of shortcomings. Firstly, vacuum tubes operated with voltages of tens of volts and consumed a lot of energy, in addition, the size electronic tubes, according to modern concepts of microelectronics, was huge - several tens of cubic centimeters. Thousands of logical elements were needed to build a computer, so the size of tube computers in terms of the occupied area was tens of square meters, and the power consumption ranged from units to tens or even hundreds of kilowatts. This power led to overheating of the lamps, which were placed rather compactly, and posed the task of effectively cooling the electronic components of the machine. The processing speed of information in tube machines ranged from several hundred to several thousand operations per second.

Lesson topic:"Digital information processing devices: digital camera»

The purpose of the lesson:

Create conditions for the formation of students' ideas about the types and purpose of digital devices for information processing;

Develop skills in information processing using various devices;

Foster respect for computer technology, compliance with the rules of safe behavior.

Students should know:

Possibilities of using digital cameras.

Lesson provision:

presentation "Digital Camera";

multimedia projector and screen;

digital camera;

DURING THE CLASSES:

Organizing time.

Greetings, organizing students for joint productive activities.

Explanation of the new material.

Vopr. What are the most common digital information processing devices you know ?:

Today we are going to take a look at digital cameras. You will study the material as follows: each of you will draw out a card with an assignment and study the material. Then, according to the numbers of the cards, you will form into groups (pairs), discuss the material together and choose a way to convey it to the others. At the end of the lesson, we should form an idea of ​​a digital camera as a means of processing and transmitting information to a computer according to the following plan:

General view, components.

Dignity.

Additional features.

Information storage methods

Communication with PC and other devices.

Card number 1

General view, components:

Basically, the device of a digital camera repeats the design of an analog one. Their main difference is in the photosensitive element on which the image is formed: in analog cameras it is a film, in digital cameras it is a matrix. Light through the lens enters the matrix, where a picture is formed, which is then written into memory. The camera consists of two main parts - the body and the lens. The body contains a matrix, a shutter (mechanical or electronic, and sometimes both at once), a processor and controls. A lens, removable or hard-wired, consists of a group of lenses housed in a plastic or metal housing.

Card number 2

Dignity

Visibility and efficiency. When shooting with digital, you see the result immediately after pressing the shutter button.

Profitability. The price of a digital camera is reduced to the level of a conventional film. You also need to consider the cost. Supplies(films, reagents, etc.)

Compactness. Small size cameras are one of the most important criteria for the amateur photographer.

Independence, reliability, easy storage. No dependence on photo printing wizard, more long term storage.

Additional features. Modern digital cameras often have a number of additional features that are fundamentally inaccessible to their film counterparts. Among them, for example, video recording, panorama shooting mode or audio commentary recording. In addition, special image processing algorithms implemented in software providing cameras, allow to partially replace such traditional photographic tools as, for example, filters and films for different types of lighting.

Digital processing.

Seal. Almost all modern digital cameras and printers support the PictBridge protocol, which provides for direct data exchange between a camera and a printing device.

Card number 3

Additional features

High-speed shooting. High-speed shooting is a mode in which the camera shoots frames not one by one, as usual, but in series - in the hope that at least one frame in a series will be successful.

Bracketing (bracketing) autofocus (exposure, white balance, flash). This special treatment, in which the camera takes several (usually 3) pictures in a row with a variation of one parameter or another.

Shooting panoramas ("stitch assist"). This function is for making panoramic shooting easier. A panorama is a series of frames taken with some horizontal or vertical displacement, and subsequently "glued" on a computer into one large image.

Macro photography. The macro function (macro mode) is a special autofocus mode that makes it possible to focus on very close subjects.

Orientation sensor. Many cameras have a so-called position or orientation sensor. The essence of its work is simple: at the time of shooting, the sensor determines in what position the camera is - in a normal or portrait position (rotated 90 degrees). If the portrait position is fixed, then after the shutter is released, two options are possible (depending on the manufacturer of the device). Either the file is recorded "as is", but a special note about "portraitity" is made in its header, or the necessary rotation by 90 degrees is performed by the camera's processor, and the frame is immediately written, "as it should.

Voice comments for pictures. Some cameras allow you to accompany the just captured footage with short voice comments. For all the seeming pretentiousness, it is quite useful opportunity... For example, during a tour of an unfamiliar city, the photographer can mark which landmark he has just photographed, and in the future this will greatly facilitate the analysis of the footage.

Video. Almost all digital cameras (except DSLRs) on the market allow video recording.

Special effects. Almost all devices have a set of special effects (or so-called filters) as an additional feature. Among them, there are usually discarding color information (monochrome image), "sepia", increasing or decreasing color intensity, etc.

Card number 4

Information storage methods.

a) Built-in memory of the camera (usually very small, allows you to store up to 10 photos)

b) Flash memory or memory cards

At the moment, there are three undisputed leaders among flash memory formats - Secure Digital, CompactFlash and Memory Stick.

Secure Digital is a standard created by an alliance of SanDisk, Matsushita Electric (Panasonic) and Toshiba. Physical dimensions modules are quite small and are 24x32x1.4 mm, which allows using this type of memory in super compact cameras. In addition, the standard provides protection against unauthorized copying (which allows you to release books in this format), as well as protection against accidental overwriting (there is a mechanical switch on the memory module). As of 2004, Secure Digital is the most popular format on the market.

Secure Digital memory module

SanDisk's CompactFlash standard provides two types of modules (Type I and Type II), differing in thickness. The dimensions of the cards are 42.8x36.4x3.3 mm and 42.8x36.4x5 mm, respectively. CompactFlash is the least compact of all formats, but in addition to memory, it produces a huge number of various peripherals for pocket computers: modems, GPS modules, WiFi and Bluetooth adapters, etc. In addition, miniatures are produced in this format. hard drives IBM / Hitachi Microdrive and Sony Microdrive from 2GB to 4GB (6GB from Western Digital is also expected). However, the feasibility of purchasing compact hard drives (in light of the collapse in prices for flash memory) is rather dubious.

CompactFlash memory module

The Memory Stick format is attributed to Sony. This format has two basic types enclosures - Memory Stick and Memory Stick Duo. The first has dimensions of 50x21.5x2.8 mm, the second - 31x20x1.6 mm. In the same form factors, there are also high-speed modifications with the ability to address more than 128 MB. They are designated by the index Pro (Memory Stick Pro and Memory Stick Pro Duo, respectively).

Module Memory Memory Stick pro

Secure Digital and CompactFlash are open standards free of any license fees. Memory Stick is a proprietary and licensed standard, so it hasn't gained much acceptance outside of Sony products. Modules of this format cost almost twice as much as the others, since license fees (royalties) are included in their price.

There are also other types of memory on the market (for example, the xD standard, developed not so long ago by Olympus and Fujifilm), the outdated MMC and SmartMedia standards, etc. However, they are much less common, and we will not dwell on them in detail.

Card No.5

Interface with computer and printer

The camera is connected to the computer to copy the footage from the flash memory, as well as, if necessary, to update the software (“firmware”) of the camera. The connection to the printer is obviously necessary for direct printing from the camera using the PictBridge protocol.

The vast majority of cameras are connected to a computer or printer via USB interface(Universal Serial Bus). For this (from the side of the camera) either a standard mini-B connector or a non-standard proprietary one is used. Obviously, the first option is somewhat preferable, since "in case something happens" you can easily buy a standard cable in any store for symbolic money, while you will have to run after a branded one (and it will cost significantly more).

At the moment, two versions are distributed USB standard: 1.1 and newer 2.0. The first provides a throughput of 12 Mbit / s, the second - 480 Mbit / s. Accordingly, if you are using a fast enough flash memory, USB 2.0 will be preferred. However, you can always remove the memory from the camera and use an external device for reading flash cards - the so-called card reader (the memory module will be presented as a medium with the FAT16 / 32 file system).

The simplest connector - RCA AV-out - to put it simply "tulips" - is adapted for connection to any television equipment, and provides viewing of images on the TV screen.

To familiarize students with the material and discussion is assigned 10 minutes ... Students then give presentations accompanied by a teacher presentation.

Summarizing the material and summing up
Questions for the class:

1. What new have you learned in the lesson?

   Was the information helpful? What is its use?

   If you were to choose a camera, what parameters would you pay attention to?

Workshop on working with a digital camera.

Note: During the lesson, you can photograph the main stages. At the end of the lesson, transfer the footage to the computer in different ways.

Homework: set by groups:

1 group - the main elements of the video camera

Group 2 - the advantages of digital video cameras

Group 3 - devices for recording information in a video camera

4 group - transfer of information from a video camera to a computer

5 group - webcams