What is the difference between bitmap and vector images?



ROBOTIC SYSTEMS:Robotic systems rely on processors to access user provided values and data. It is essential to note here that all the data is sent via the processor in a binary format so conversions and storage has to be provided by the processor.Example 11905060960The device on the left is a mobile trolley with 3 wheels. All three wheels can turn left or right and each wheel has its own electric driving motor. Sensors at the front and rear of the trolley detect an object in its path which would subsequently stop all movement. An 8-bit register is used to418465394335control the device.15875297180Chapter: 1.1 Data representationHence, the trolley is moving forward and turning left.15875124460(i) What does this register mean?“0 0 0 1 0 1 1 1”(ii) How would the following be represented using the above register?front wheel turning rightback wheels turning leftmoving in a forward directionmotors onno object in its pathAnswersfront wheel not turning left or rightRear wheels turning rightgoing in backward directionmotors onError – object in pathSo the vehicle is going nowhere.(ii) 0 1 1 0 1 0 1 01.1.1 Binary systemsChapter: 1.1 Data representationEXAMPLE#2:SENSORS IN PRINTING DEVICES:Three sensors are attached to a printing device, with three alarms attached to the sensors. The first sensor, "A," detects if the device needs ink. The second sensor, "B," detects if the device needs repair. The third sensor, "C," detects if the device has jammed paper. If the device jams or needs repair, alarm 1 sound. If the device jams or is short on ink, alarm 2 sounds. If two or more problems occur at once, alarm 3 sounds.It can now be implied that:A=1 refers to “low ink”B=1 refers to “Device needs repair”C=1 refers to “device should jam”The outputs to the system are as follows:A1: alarm 1 sounds if B=1 or C=1(either of B=1 or C=1 will result in A1)A2: Alarm 2 sounds if C=1 or A=1 (either of A or C being true will result in A2)A3= any two or more of A, B, and C being ‘1’ will result in A3.Let us now look at the cases that will form:1905013335Questions:1) What binary values can the register hold to alert the user of a “low ink” situation?2) The register is holding “010”. Which alarm will sound?3) Is the system accurate in telling the user of exactly which problem is being occurred? Point out any one situation where user is misguided?Answers:1) 010, 111, 111, 1112) A2 will sound.3) No. System has the same alarm for one problem or more than one problem. E.g. 111 could mean thatall three problems have occurred but 111 can be received even if printer is “full on ink” or not having“jammed paper.”Binary system17145516255PSEPSPSEPSEUDOCODE EXAMPLES WITH SOLUTIONS -144780173355-43910254838701714537465-2172335335915171451905-440118522606015875-114935-342836570485-37331650171451905-41719503119755-79375-1270-79375295910-79375-53975171450-41719502762253708402781300-201930825517145132080102870876301714515875-41522652889252540302260624840-1268730-8763047625-571436550800340995249555295910114300243205172085017145109220-2984599060-4133215201295-4445023431566040104775-21780589535VON NEUMANN ARCHITECTUREAlthough computers can have many different forms, there are four functional components that all computers must have:Input/Output (I/O)MemoryA Control UnitAn Arithmetic Logic Unit (ALU)This idea about how computers should be built, called the von Neumann Architecture after mathematician John von Neumann who proposed it in 1945, is still the basis for computers today. Using these four components, a von Neumann computer will execute a series of instructions, called a program, which are stored in the computer's memory. This is called the stored program concept.INPUT/OUTPUT (I/O):The Input/Output (I/O) components of a computer are hardware devices that are responsible for getting data from the computer to the user or from the user to the computer. Data going from the user to the computer is called "input." The two main input devices are the mouse and the keyboard. With both of these devices the user can transmit information (in letters or clicks) to the computer. These are not the only types of input devices that are possible -- there are also graphics tablets, touch screens, and voice recognition devices, among others.Output devices are used to transmit data from the computer's memory to the user. The two output devices almost every computer system has are the monitor and the printer. Another common output device is a speaker system for sound. The specific input devices change over time, but every computer must have input and output devices.The remaining three components of the von Neumann model of a computer are found inside the system unit.MEMORY :Although a computer has several types of memory, the memory referred to in the Von Neumann model is the main memory, also called RAM or Random Access Memory. Main memory is used by the computer for storing a program and its data while the program is running. What distinguishes a computer from a calculator is the ability to run a stored program; main memory allows the computer to do that.RAM can be thought of as a sequence of boxes, called cells, each of which can hold a certain amount of data. RAM is constructed from circuitry that can hold data in the form of an electronic charge that is either high or low. Conceptually, a high charge represents the number 1 and a low charge the number 0.RAM must be coded in binary - in terms of 0's and 1's. One of the high or low charges stored in memory (one 0 or one 1) is called a bit and 8 bits is called a byte. For every computer, each memory cell can hold a certain fixed number of bits, usually 8.A CONTROL UNIT :Inside the computer, the remaining two components of the von Neumann Architecture are found on the CPU (Central Processing Unit) chip. The control unit controls the sequencing and timing of all operations. It contains a "clock," that is actually a quartz crystal (Quartz is a type of crystal used in watches, computers, and other devices to keep time. The .0.quartz crystal vibrates or ticks an exact 60-seconds per minute when electricity is applied to it ) that oscillates at a regular frequency when electrical power is applied. The clock emits an electronic signal for each oscillation. Each separate operation is synchronized to the clock signal.The three main elements of the control unit are as follows:DecoderThis is used to decode the instructions that make up a program when they are being processed, and to determine in what actions must be taken in order to process them. These decisions are normally taken by looking at the opcode of the instruction, together with the addressing mode used. This is covered in greater detail in the instruction execution section of this tutorial.Timer or clockThe "clock" is the heart beat of any processor... The processor executes one thing at "a time": the time is given by the clock. The clock is just an oscillator running 0,1,0,1,0... Each time the clock changes level, the processor executes ONE instruction. (Not totally true, as some instructions require more than one clock, but take it as I said!) Control logic circuitsThe control logic circuits are used to create the control signals themselves, which are then sent around the processor. These signals inform the arithmetic and logic unit and the register array what they actions and steps they should be performing, what data they should be using to perform said actions, and what should be done with the results. AN ARITHMETIC LOGIC UNIT (ALU):Also on the CPU chip is circuitry for performing arithmetic and logical calculations. This is called the Arithmetic/Logic Unit or ALU for short. It can be thought of as being similar to a calculator, except that, in addition to normal math, it can also do logical (true/false) operations, such as comparing two numbers to see which one is larger. Logical operations are important in computer programming.HOW IT ALL WORKS:No matter what you are doing on a computer, it is always running one or more computer programs. A computer program is just a series of computer instructions. At the most basic level, a computer instruction may be something simple like adding two numbers and storing the result. Even complicated computer programs at the deepest level, the computer just does one thing -- it executes one instruction after another, over and over, millions of times every second.In the next section we will see how a simplified model of a computer uses the basic hardware components we have discussed (memory, the control unit, and the ALU) - and some we haven't (registers, bus) - in order to execute instructions.THE INSTRUCTION CYCLE INTRODUCTION THE COMPUTER MODEL :To illustrate how a computer works - how it executes one instruction - we will use a simplified model of a computer, using the memory, control unit, and ALU components that we have already discussed. The control unit and the ALU are both found on the CPU (central processing unit).In addition to these main components, there are 3 smaller components within the CPU that require explanation when demonstrating how a computer executes an instruction.A register is a small, fast unit of memory located on the CPU, and used temporarily for storing data. Because the registers are close to the ALU, they are made out of fast memory, efficiently speeding up calculations. This model shows 4 general-purpose registers, but computers usually have 16 or more.The computer model also needs a decoder - circuitry that will take a computer instruction stored in main memory in binary (as a long string of 0's and 1's) and then convert it to signals that can execute an instruction. Transmitting data between the different components is done using circuitry known as a data bus or bus. One bus connects memory to the CPU and another bus connects the relevant parts of the CPU.THE INSTRUCTION CYCLE MACHINE AND ASSEMBLY LANGUAGE INSTRUCTIONS :What distinguishes a computer from a calculator is that the computer stores its program, the instructions it will be executing, in its own memory. Computer instructions are encoded and stored in memory as a language called machine code or machine language.However, there is another language called assembly language, which uses more English like words to tell the computer what to do. The upcoming animations will use assembly language to issue commands.THE INSTRUCTION CYCLE BASIC STEPS OF THE INSTRUCTIONS CYCLE :1150620701040At its core, all the computer ever does is execute one instruction in memory after another, over and over. Although there are many different possible (assembly language) instructions that the computer can execute, the basic steps involved in executing an instruction are always the same, and they are called the instruction cycle1. Fetch the instruction (transfer the instruction from main memory to the decoder)2. Decode the instruction (from machine language)3. Execute the instruction (e.g., add, divide, load, store...)4. Store the result (for instructions like ADD, place the 'answer' in the specified register.)The control unit guides the computer's components through this cycle to execute one instruction.When that instruction is done, the cycle starts all over again with the next instruction.1905036417253429030797519050160020There is a special register, called the program counter (PC) that stores the address of the next instruction.19050246380In the example above the PC says the next instruction is in memory location 8.19050421640The decoder will decode the instruction. This instruction says to store the data in R2 in memory location 2000For this instruction, there is not a separate STORE step - the instruction is done.SUMMARY :Throughout their brief history, the physical appearance of computers has changed dramatically, but their basic function - to store and execute a series of instructions - has remained the same.The von Neumann model of computer architecture characterizes computers as having four functional units: I/O, Memory, Control Unit and ALU. Basically all the computer ever does is repeat the four steps of the instruction cycle -- fetch, decode, execute and store -- over and over.2nd version of VON NEUMANN ARCHITECTUREOnce a program is in memory it has to be executed. To do this, each instruction must be looked at, decoded and acted upon in turn until the program is completed. This is achieved by the use of what is termed the 'instruction execution cycle', which is the cycle by which each instruction in turn is processed. However, to ensure that the execution proceeds smoothly, it is also necessary to synchronize the activities of the processor. To keep the events synchronized, the clock located within the CPU control unit is used. This produces regular pulses on the system bus at a specific frequency, so that each pulse is an equal time following the last. This clock pulse frequency is linked to the clock speed of the processor - the higher the clock speed, the shorter the time between pulses. Actions only occur when a pulse is detected, so that commands can be kept in time with each other across the whole computer unit.The instruction execution cycle can be clearly divided into three different parts, which will now be looked at in more detail. For more on each part of the cycle click the relevant heading, or use the next arrow as before to proceed though each stage in order.Fetch CycleThe fetch cycle takes the address required from memory, stores it in the instruction register, and moves the program counter on one so that it points to the next instruction.Decode CycleHere, the control unit checks the instruction that is now stored within the instruction register. It determines which opcode and addressing mode have been used, and as such what actions need to be carried out in order to execute the instruction in question.Execute CycleThe actual actions which occur during the execute cycle of an instruction depend on both the instruction itself, and the addressing mode specified to be used to access the data that may be required. However, four main groups of actions do exist, which are discussed in full later on.The first part of the instruction execution cycle is the fetch cycle. Once the instruction has been fetched and stored in the instruction register, it must then be decoded.Once the instruction has been fetched and is stored, the next step is to decode the instruction in order to work out what actions should be performed to execute it. This involves examining the opcode to see which of the machine codes in the CPU's instruction set it corresponds to, and also checking which addressing mode needs to be used to obtain any required data. Therefore, using the CPU model from this tutorial, bits 16 to 23 should be examined.Once the opcode is known, the execution cycle can occur. Different actions need to be carried out dependant on the opcode, with no two opcodes requiring the same actions to occur. However, there are generally four groups of different actions that can occur:Transfer of data between the CPU and memory.Transfer of data between the CPU and an input or output devices.Processing of data, possibly involving the use of the arithmetic and logic unit.A control operation, in order to change the sequence of subsequent operations. These can possibly be conditional, based on the values stored at that point within the flag register.For greater simplicity, and as describing all the possible instructions is unnecessary, the following tutorial pages will only look at a few possible instructions. These are:Mnemonic DescriptionMOVMoves a data value from one location to anotherADDAdds to data values using the ALU, and returns the result to the accumulatorSTOStores the contents of the accumulator in the specified locationENDMarks the end of the program in memoryThe four instructions used in the examples for the remainder of this section of the tutorialThe following three pages of the tutorial will look at the first two of these instructions, and how they are executed in each of the three main addressing modes. These addressing modes are:Immediate addressingWith immediate addressing, no lookup of data is actually required. The data is located within the operands of the instruction itself, not in a seperate memory location. This is the quickest of the addressing modes to execute, but the least flexible. As such it is the least used of the three in practice.Direct addressingFor direct addressing, the operands of the instruction contain the memory address where the data required for execution is stored. For the instruction to be processed the required data must be first fetched from that location.Indirect addressingWhen using indirect addressing, the operands give a location in memory similarly to direct addressing. However, rather than the data being at this location, there is instead another memory address given where the data actually is located. This is the most flexible of the modes, but also the slowest as two data lookups are required.The first of the three addressing modes to be looked at is immediate addressing. When writing out the code in mnemonic form, operands that require this mode are marked with a # symbol. With immediate addressing, the data required for execution of the instruction is located directly within the operands of the instruction itself. No lookup of data from memory is required.The next of the three addressing modes that will be looked at is direct addressing.The second of the three addressing modes to be looked at is direct addressing. When writing out the code in mnemonic form, no symbol is required to mark operands which use this form. Direct addressing means that the operands of the instruction hold the address of the location in memory where the data required can be found. The data is then fetched from this location in order to allow the instruction to be executed. The final of the three modes of addressing to be looked at is indirect addressing .When writing out the code in mnemonic form, operands that require this mode are marked with a @ symbol. Indirect addressing means that the memory address given in the operands of the instruction is not the location of the actual data required. Instead, that address holds a further address, at which the data is stored. This can prove useful if decisions need to be made within the execution, as the memory address used in processing can be changed during execution. Now that we have covered all the stages of the instruction execution process, and also the three main addressing modes that are used, we are able to examine the full execution of simple programs.FETCH DECODE EXECUTE1905010160017677186952176771329675371134-141681THE LITTLE MAN COMPUTER (LMC) - Download the softwareA Little Man Computer (LMC) is a simulator which has many of the basic features of a modern computer that uses the Von Neumann architecture (a?central processing unit?consisting of an?arithmetic logic unit?and registers, a?control unit?containing an?instruction register?and?program counter, input and output?mechanisms and RAM to store both data and?instructions).The LMC is based on the idea of a 'Little Man' acting like the control unit of a CPU, fetching instructions? from RAM, decoding and executing them as well as managing the input and output mechanisms.The two versions on this website can be programmed by using a basic set of 10 assembly code instructions which are then assembled into machine code (although in decimal not binary).Instruction Mnemonic Machine Code Load LDA 5xx Store STA 3xx Add ADD 1xx Subtract SUB 2xx Input INP 901 Output OUT 902 End HLT 000 Branch always BRA 6xx Branch if zero BRZ 7xx Branch if zero or positive BRP 8xx Data storage DAT Input and OutputThe following program will demonstrate the INPUT and OUTPUT instructions of the LMC.Running the program: the program simply INPUTS a number, then OUTPUTS it.INPOUTHLTInstructions:Copy the three-line program above and paste it into the Program box.Click on the "Assemble Program" button.After the program is assembled you should see RAM addresses 0 to 2 contain the machine code instructions shown in the image.Click on the RUN button.When prompted, INPUT a number. Don’t use keyboard for entering values instead use calculator of accumulator thru mouse. If you have difficulty following what is happening, read the explanation below and use STEP instead of RUN so you can follow each step.Explanation:INP??? //the input value is copied into the accumulator.OUT??? //the value in the accumulator is sent to the OUTPUT.HLT??? //the program halts.Example results:INPUT? = 2OUTPUT = 2LOAD AND SAVEThe following program will demonstrate the use of LDA and STA, the Load and Save instructions used in the LMC instruction set.Running the program: when prompted, INPUT a set of two numbers. The program should then OUTPUT them in the same order that they were entered.INPSTA firstINPSTA secondLDA firstOUTLDA secondOUTHLTfirst DATsecond DAT 0 INP1 STA 92 INP3 STA 104 LDA 95 OUT6 LDA 107 OUT8 HLT9 DAT 010 DAT 0 Instructions:Copy the eleven line program above and paste it into the Program box.Click on the "Assemble Program" button.After the program is assembled you should see RAM addresses 0 to 8 contain the machine code instructions shown in the image.Click on the RUN button.If you have difficulty following what is happening, read the explanation below and use STEP instead of RUN so you can follow each step.Explanation:first and second are used to label a DAT instruction. DAT identifies the 10th and 11th instructions as data. The labels therefore refer to RAM addresses 9 and 10 respectively (0-indexed counting).0 INP???? //the first input value is copied into the accumulator.1 STA first//the accumulator contents are stored in RAM address 9 (labelled first).2 INP????????? //the second input value is copied into the accumulator.3 STA second?? //the accumulator contents are stored in RAM address 10 (labelled second).4 LDA first??? //the contents of memory address 9 (labelled first) are loaded into? the accumulator.5 OUT????????? //the value in the accumulator is sent to the OUTPUT.6 LDA second?? //the contents of memory address 10 (labelled second) are loaded into the accumulator.7 OUT????????? //the value in the accumulator is sent to the OUTPUT.8 HLT????????? //the program halts.Example results:INPUT= 2, 3OUTPUT = 2, 3ADDITION AND SUBTRACTIONThe following program will demonstrate the ADD and SUB instructions of the LMC instruction set.? Running the program: when prompted, INPUT a set of three numbers. The program should add the first two numbers and output the answer, then subtract the first number from the third and output the answer.INPSTA firstINPADD firstOUTINPSUB firstOUTHLTfirst DAT 0 INP1 STA 92 INP3 ADD 94 OUT5 INP6 SUB 97 OUT8 HLT9 DAT 0 Instructions:Copy the ten line program above and paste it into the Program box.Click on the "Assemble Program" button.After the program is assembled you should see RAM addresses 0 to 8 contain the machine code instructions shown in the image.Click on the RUN button.If you have difficulty following what is happening, read the explanation below and use STEP instead of RUN so you can follow each step.Explanation:first is used to label a DAT instruction. DAT identifies the 10th instruction as data. The label therefore refers to RAM address 9 (0-indexed counting).0 INP???????? //the first input value is loaded into the accumulator.1 STA first?? //the accumulator contents are stored in RAM address 9 (labelled first).2 INP???????? //the second input value is loaded into the accumulator.3 ADD first?? //add the contents of RAM address 9 (labelled first) to the accumulator and store the result in the accumulator.4 OUT???????? //the value in the accumulator is sent to the OUTPUT.5 INP???????? //the third input value is loaded into the accumulator.6 SUB first?? //subtract the contents of RAM address 9 (labelled first) from the accumulator and store the result in the accumulator.7 OUT???????? //the value in the accumulator is sent to the OUTPUT.8 HLT???????? //the program halts.Example results:INPUT= 2 (stored in RAM address 9)INPUT = 3OUTPUT = 5 (the contents of the accumulator PLUS the contents of RAM address 9)INPUT = 8OUTPUT = 6 (the contents of the accumulator MINUS the contents of RAM address 9)TRANSFER TIME ESTIMATIONFile sizes are measured in BYTES while bandwidths are measured in bits. In order to know file transfer time first convert either bits to bytes or bytes to bits.If we transfer file bytes to bits then divided more bits (file bits) by less bits (bandwidth bits) to find out time required to transfer the file over given bandwidth.Example:Q1. how much time will a 2 MB file take to get transferred over a 2mbps connection?Lets transfer 2MB file size to bits:1024 (KB) * 1024 (KB) * 2 (MB) * 8 (bits) = 16777216 bitsbandwidth:1024 * 1024 * 2 = 2097152 bitsTransfer time:16777216 / 2097152 = 8 secondsAnother method : 2MB * 8 = 16 mbps Time=file size/speed 16/2=8 secondsQ2. How many minutes required to upload a 75 Mbyte file at 2 megabits/second upload speed?75 x 8=600 megabits?Speed = 2megabits per sec?Time = file size/speed =600/2?= 300 seconds = 5 minutesQ3. A digital camera contains a microprocessor. The camera’s specification includes:? 20 megapixel resolution? 32 gigabyte memory cardIf a compressed image file requires an average of 1 byte per pixel, what is the maximum number of photos that can be stored on the memory card?20/1024=0.01953125?32/0.01953125= 1638 photos SOUND RECORDINGSound is an analogue phenomenon which is recorded in number samples per second called sampling rate. Every sample has a size in bits, called sample resolutionSound file Size: Samples * resolution * time in seconds = size in bits / 8 = # bytes.Sound is captured using mic, that converts sound to electrical voltage that is converted to binary form using ADC (analogue to digital converter). Digitized sound then can be recorded, editing and replayed over speakers using DAC (digital to analogue converter.)Data storage of sound (music), pictures, video, text and numbersTEXT:Text can be represented easily by assigning a unique numeric value for each symbol used in the text. For example, the widely used ASCII code (American Standard Code for Information Interchange) defines 128 different symbols (all the characters found on a standard keyboard, plus a few extra), and assigns to each a unique numeric code between 0 and 127. In ASCII, an "A" is 65," B" is 66, "a" is 97, "b" is 98, and so forth. When you save a file as "plain text", it is stored using ASCII. ASCII format uses 1 byte per character 1 byte gives only 256 (128 standard and 128 non-standard) possible characters. The code value for any character can be converted to base 2, so any written message made up of ASCII characters can be converted to a string of 0's and 1's.What is the difference between bitmap and vector images?Bitmap (or raster) images are stored as a series of tiny dots called pixels. Each pixel is actually a very small square that is assigned a color, and then arranged in a pattern to form the image. When you zoom in on a bitmap image you can see the individual pixels that make up that image. Bitmap graphics can be edited by erasing or changing the color of individual pixels using a program such as Adobe Photoshop. Unlike bitmaps, vector images are not based on pixel patterns, but instead use mathematical formulas to draw lines and curves that can be combined to create an image from geometric objects such as circles and polygons. Vector images are edited by manipulating the lines and curves that make up the image using a program such as Adobe Illustrator. GRAPHICS :Graphics that are displayed on a computer screen consist of pixels: the tiny "dots" of color that collectively "paint" a graphic image on a computer screen. The pixels are organized into many rows on the screen. In one common configuration, each row is 640 pixels long, and there are 480 such rows. Another configuration (and the one used on the screens in this lab) is 800 pixels per row with 600 rows, which is referred to as a "resolution of 800x600." Each pixel has two properties: its location on the screen and its color. A graphic image can be represented by a list of pixels. Imagine all the rows of pixels on the screen laid out end to end in one long row. This gives the pixel list, and a pixel's location in the list corresponds to its position on the screen. A pixel's color is represented by a binary code, and consists of a certain number of bits. In a monochrome (black and white) image, only 1 bit is needed per pixel: 0 for black, 1 for white, for example. A 16 bit color image requires 4 bits per pixel. Modern display hardware allows for 24 bits per pixel, which provides an astounding array of 16.7 million possible colors for each pixel! DIGITAL VIDEO:A single frame of video data can be quite large in size. A video frame with a resolution of 512 x 482 will contain 246784 pixels. If each pixel contains 24 bits of color information, the frame will require 246784*24= 5922816 /8= 740352 bytes of memory or disk space to store. Assuming there are 30 frames per second for real-time video, a 10-second video sequence would be more than 222 megabytes in size! It is clear there can be no computer video without at least one efficient method of video data compression. Tied up with encodings is the concept of compression. Video information can be stored on a medium in an uncompressed format, that is, a format in which there is a one-to-one mapping between the picture information and the data stored. However, it is much more common to have a degree of compression, i.e. reduction in the amount of space needed to store the information on the medium.Video data normally occurs as continuous, analog signals. In order for a computer to process this video data,We must convert the analog signals to a non-continuous, digital format. In a digital format, the video data can be stored as a series of bits on a hard disk or in computer memory. The process of converting a video signal to a digital bit stream is called analog-to-digital conversion (A/D conversion), or digitizing. A/D conversion occurs in two steps: 1. Sampling captures data from the video stream. 2. Quantizing converts each captured sample into a digital format. Each sample captured from the video stream is typically stored as a 16-bit integer. The rate at which samples are collected is called the sampling rate. The sampling rate is measured in the number of samples captured per second (samples/second). For digital video, it is necessary to capture millions of samples per second.AUDIO/SOUND:An audio file format is a file format for storing digital audio data on a computer system. The bit layout of the audio data is called the audio coding format and can be uncompressed, or compressed to reduce the file size, often using lossy compression.It is important to distinguish between the audio coding format, the container containing the raw audio data, and an audio codec. A codec performs the encoding and decoding of the raw audio data while this encoded data is (usually) stored in a container file. There are three major groups of audio file formats:Uncompressed audio formats, such as WAV, AIFF, AU or raw header-less PCM;Formats with lossless compression, such as FLAC, Monkey's Audio (filename extension .ape), WavPack (filename extension .wv), TTA, ATRAC Advanced Lossless, ALAC (filename extension .m4a), MPEG-4 SLS, MPEG-4 ALS, MPEG-4 DST, Windows Media Audio Lossless (WMA Lossless), and Shorten (SHN).Formats with lossy compression, such as MP3, Vorbis, Musepack, AAC, ATRAC and Windows Media Audio Lossy (WMA lossy).A digital recorder captures a wave form at specific intervals, called the sampling rate. Each captured wave-form snapshot is converted to a binary integer value and is then stored on disk. MIDI STANDARD:Musical Instrument Digital Interface (MIDI) is an industry standard for representing sound in a binary format. MIDI is not an audio format, however. It does not store actual digitally sampled sounds. Instead, MIDI stores a description of sounds, in much the same way that a vector image format stores a description of an image and not image data itself. Sound in MIDI data is stored as a series of control messages. Each message describes a sound event using terms such as pitch, duration, and volume. When these control messages are sent to a MIDI-compatible device (the MIDI standard also defines the interconnecting hardware used by MIDI devices and the communications protocol used to interchange the control information) the information in the message is interpreted and reproduced by the device. MIDI data may be compressed, just like any other binary data, and does not require special compression algorithms in the way that audio data does.AUTOMATIC REPEAT REQUEST (ARQ) (sometimes also referred to as backward error correction): Automatic Repeat ReQuest (ARQ), also called Automatic Repeat Query, is an error-control protocol that automatically initiates a call to retransmit any data packet or frame after receiving flawed or incorrect data. When the transmitting device fails to receive an acknowledgement signal to confirm the data has been received, it usually retransmits the data after a predefined timeout and repeats the process a predetermined number of times until the transmitting device receives the acknowledgement.CHECKSUM:A checksum is a count of the number of bits in a transmission unit that is included with the unit so that the receiver can check to see whether the same number of bits arrived. If the counts match, it's assumed that the complete transmission was received.Serial vs. Parallel data transmission:In serial transmission, bits are sent sequentially on the same channel (wire) which reduces costs for wire but also slows the speed of transmission. Also, for serial transmission, some overhead time is needed since bits must be assembled and sent as a unit and then disassembled at the receiver. E.g Keyboard , mouse cables, Serial ATA and HDMI.In parallel transmission, multiple bits (usually 8 bits or a byte/character) are sent simultaneously on different channels (wires, frequency channels) within the same cable, and synchronized to a clock, there is a speedup in parallel transmission bit rate over serial transmission bit rate. However, this speedup is a tradeoff versus cost since multiple wires cost more than a single wire. Data within a computer system is transmitted via parallel mode on buses with the width of the parallel bus matched to the word size of the computer. show understanding of the need to check for errorsErrors occur in data as it moves around a computer and across networks. There are various strategies to overcome this, including: repetition, parity and checksums.1. Repetition: Data bits are repeated n times e.g. 1 is sent as 111 (3 times repetition).2. Parity: Parity is reserved and set to 0 or 1 according to the number of 1s in a data word.In even parity an even number of 1s will set the parity bit to 0 (so there is an even number of 1s) while an odd number of 1s will set the parity bit to 1 (so there is an even number of 1s).In odd parity an even number of 1s will set the parity bit to 1 (to maintain the odd number of 1s) while an odd number of 1s will set the parity bit to 0 (to maintain the odd number of 1s).3. Checksum: The numeric value of data words is added before transmission and the checksum sent with the data. The same calculation is performed after transmission to see if the checksums match. If the checksums do not match an error occurred and the data are transmitted again.4. Check digit: e.g. ISBN 10 ISBN 13Identify current uses of serial and parallel data transmission, such as Integrated Circuits (IC) and Universal Serial Bus (USB): An RS-232 serial port was once a standard feature of a personal computer, used for connections to modems, printers, mice, data storage, uninterruptible power supplies and other peripheral devices. However, the low transmission speed, large voltage swing, and large standard connectors motivated development of the Universal Serial Bus, which has displaced RS-232 from most of its peripheral interface roles." (Wikipedia) "Universal Serial Bus (USB) is an industry standard developed in the mid-1990s that defines the cables, connectors and communications protocols used in a bus for connection, communication, and power supply between computers and electronic devices." (Wikipedia) USB was designed to standardize the connection of computer peripherals to personal computers.They communicate data and supply power and have replaced other interfaces Communications between devices such as computers and printers and across networks is performed adequately with serial lines. Data transmission over much shorter distances inside integrated circuits (ICs) is best done using parallel channels. ICs employ three buses for communication:Data bus: carries data between memory and processor and also between ports and other parts e.g. sound card, graphics card, have own processors and memory and some data are moved to processor and main memory; bi-directional, data flow to processor and back to memory.Address bus: carries address from processor to location in main memory (some ports may be memory-mapped so have addresses too); unidirectional, no need for an address to flow back to processor.Control bus: carries signals from processor to parts of CPU and system to activate something e.g. to read or write data to a memory location or I/O These buses use parallel channels rather than single, serial ones. Speed and throughput of data are of prime concern in IC design so it makes sense to maximize this with as many lines as possible.MP3:MP3 is short for MPEG-1 Audio Layer 3.? It is used for audio and uses a compression algorithm that introduces loss, meaning it is a “lossy” compression format.? It is one of the most commonly used audio formats available and has been the standard for quite some time.MP3 works to make file sizes smaller by using what is called psychoacoustic models.? They get rid of data that most people would not hear because it is too low or high. ?By doing this, files sizes can be greatly reduced.MP4:MP4 is short for MPEG-4 Part 14.? MP4 is based on MPEG-4 Part 12 which was in turn based on Apple’s MOV file type.? MP4 is a container format, meaning it is used to store audio and/or video data, rather than to code the information.? MP4 video and audio can also be streamed over the internet.? This is also true of most other modern container formats.So What’s the Difference Then?From these two descriptions, we can note a few major differences.? First, MP3 is an audio compression format used to compress and store audio on a computer.? MP4 is a media container format used to store media of many possible types on a computer.Therefore, an MP3 file is limited with regard to the method of compression and can only store audio.? MP4 on the other hand, can store video as well as audio.? It can even store subtitles for a video file.? Also, since MP4 is a container, it can store audio and video that have been compressed in different fashions.? In fact, an MP4 file could be audio that has been compressed as an MP3.What are Internet Servers? In general, all of the machines on the Internet can be categorized as two types: servers and clients. Those machines that provide services (like Web servers or FTP servers) to other machines are servers. And the machines that are used to connect to those services are clients. When you connect to “Yahoo!” at to read a page, Yahoo! is providing a machine (probably a cluster of very large machines), for use on the Internet, to service your request. Yahoo! is providing a server. Your machine, on the other hand, is probably providing no services to anyone else on the Internet. Therefore, it is a user machine, also known as a client. It is possible and common for a machine to be both a server and a client, but for our purposes here you can think of most machines as one or the other. A server machine may provide one or more services on the Internet. For example, a server machine might have software running on it that allows it to act as a Web server, an e-mail server and an FTP server. Clients that come to a server machine do so with a specific intent, so clients direct their requests to a specific software server running on the overall server machine. For example, if you are running a Web browser on your machine, it will most likely want to talk to the Web server on the server machine. Your Telnet application will want to talk to the Telnet server, your e-mail application will talk to the e-mail server, and so on. Hypertext Transfer Protocol (http) :Short for Hypertext Transfer Protocol, the underlying protocol used by the World. HTTP defines how messages are formatted and transmitted, and what actions Web servers and browsers should take in response to various commands. For example, when you enter a URL in your browser, this actually sends an HTTP command to the Web server directing it to fetch and transmit the requested Web page. There is much more to HTTP than simply sending the message that an end user wants to see a web page. HTTP actually identifies eight different methods which indicate what the desired action is and what action should be performed. These eight different methods are: HEAD – Asks for the material in a GET request, but without the response body. GET – Requests the representation of a specified source with a response body. POST – Submits the data to be processed from an HTML form to the identified source. PUT – Uploads a representation of the source that has been specified. DELETE – Deletes a specific source. TRACE – This echoes back a specific request so that the user can see what servers are adding or changing the request. OPTIONS – Used to check the functionality of a web server by returning the HTTP methods that the server supports for a specified URL. CONNECT – Facilitates SSL-encrypted communication through an unencrypted HTTP proxy by converting the request connection to a transparent TCP/IP tunnel. Important to communication and the way the entire Internet works, the hypertext transfer protocol or HTTP is a necessary protocol.Solid-state disk (SSD):SSD devices use much less power and produce less heat than hard disks. But until their prices come down, they'll at best be niche devices. Although?solid-state disk (SSD)?devices typically offer access speeds 200 or so times faster than hard disks, so far the high price of solid-state memory has kept these devices confined to niches in the data center.3D scanner?:A?3D scanner?is a device that analyses a real-world object or environment to collect data on its shape and possibly its appearance (e.g. colour). The collected data can then be used to construct digital?three-dimensional models.Many different technologies can be used to build these 3D-scanning devices; each technology comes with its own limitations, advantages and costs. Many limitations in the kind of objects that can be digitised are still present, for example, optical technologies encounter many difficulties with shiny, mirroring or transparent objects. For example,?industrial computed tomography scanning?can be used to construct digital 3D models, applying?non-destructive testing.Laser Cutter (3D):The laser cutter is a machine that uses a laser to cut materials such as chip board, matte board, felt, wood, and acrylic up to 3/8" (1?cm) thickness. The laser cutter is often bundled with a driver software which interprets vector drawings produced by any number of CAD software platforms.The laser cutter is able to modulate the speed of the laser head, as well as the intensity and resolution of the laser beam, and as such is able both cut and score material, as well as approximate raster graphics.LED/LCD:An?LED TV?uses less power, provides a brighter display with better contrast, a thinner panel, and lesser heat dissipation than a conventional?LCD TV. This is because an LED TV uses light-emitting diodes for backlighting as opposed to the?CCFLs?of conventional LCD TVs. The display of an LED TV is not an?LED display, so a more technically correct name for it would be "LED-backlit LCD television."The LCD television is a flat-panel television which utilizes a Liquid Crystal Display technology. It has two layers of glass which are polarized and stuck together. The liquid?crystals?are held in one of the layers. These liquid crystals pass, or block the light, to produce images on the screen when the electric current passes through it.However, the crystals do not produce their own light. The light comes from the series of fluorescent lamps at the back of the screen. There are millions of shutters arranged in a grid, which open and close to release and trap some of the light that is not needed to create images.LED TV’s are actually very much like LCD TV’s. They also have a flat-screen which utilizes Liquid Crystal Display technology. The only difference is their source of light, which is at the back of the screen. The LCD TV uses fluorescent lamps, and the LED TV uses LED (Light Emitting Diodes).LCD Projectors vs. DLP Projectors -When shopping for a digital projector, your first question might well be:?“Which type of projector technology is the best, and what is the difference?”The two main contenders are Liquid Crystal Display (LCD) projectors and Digital Light Processing (DLP) projectors. These terms refer to the mechanism the projector uses internally to compose images. It can be a hard decision as both projection technologies have strengths and weaknesses, and it is important to know the differences so you can choose which technology matches your needs. In this Bamboo AV Advice article we will explain the technology behind LCD and DLP projectors, and then compare them so you are better placed to make a decision on which type of projector to buy.How does LCD technology work?LCD projectors project light onto mirrors which split it up into its 3 primary colours: red, green and blue. The colours then pass through three separate glass panels (actually prisms), which is why this technology is referred to as 3LCD. When light is projected through the LCD panels, individual pixels are opened or closed to allow light through or block it. The separate colours are then converged using another prism and projected on to the screen.182233055How does DLP technology work?Digital Light Processing is a proprietary system developed by Texas Instruments, and works differently to LCD projection. Most DLP projectors have a single chip instead of glass panels through which light is passed, and this chip has a reflective surface composed of thousands of tiny mirrors which correspond to individual pixels. These mirrors can move back and forth when light is beamed onto the chip to direct the light from individual pixels either towards the projector lens or away from it. In order to define colours, DLP projectors have a colour wheel that consists of red, green and blue filters. This wheel spins between the light source and the DLP chip and alternates the colour of the light hitting the chip between red, green and blue. The mirrors tilt away from or into the lens path depending on how much of each color is required for each pixel at any given moment.18223-26178-106680427355The two technologies are therefore quite different, and so it is not surprising that LCD and DLP projectors differ in terms of their performance and their usefulness for different applications. ................
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