Contents. Media Files and Formats. The prehistory. Pre-Digital Formats
|
|
- Oswin Washington
- 6 years ago
- Views:
Transcription
1 Contents Media Files and Formats CSCU9B2 Prehistory: analogue Digital formats Compression Proprietary vs Free formats Image formats Audio formats Video formats CSCU9B2 1 CSCU9B2 2 The prehistory The prequel: analogue CSCU9B2 3 Pre-Digital Formats In the 1980s and before, most media was analogue Music was recorded on vinyl or magnetic tape Photos were taken onto light sensitive film and printed onto paper Nothing was turned into numbers storage was physically related to the sound or look of the media In that sense what was recorded was analogous to what was being stored CSCU9B2 4
2 Audio recording This was first invented in 1877 by Thomas Edison (on a cylinder) (analogue) Moved to disc from about Commercial recordings started in the 1900 s, and the disc overtook the cylinder about CSCU9B2 5 Audio analog recording techniques Early recordings were analogue. Precise shape of groove is a representation of the original signal. It is recorded by replicating the pressure wave into a pattern made in a groove on the substrate (wax/shellac/vinyl) And played back by placing a fine stylus in the groove, turning the signal into an analogue electrical signal, amplifying it, and then turning the analogue signal back into a pressure wave. CSCU9B2 6 Analogue Audio: tape Physical recordings are write-once/read often Tape recordings Made by encoding the pressure wave in the pattern of magnetisation on the magnetic particles on a tape allow write often/read often usage Useful for Portable recordings Erasable recordings Formats: Reel to reel Cassette European format and 8 track But still analogue What happened? Analog recording was the dominant technology for most of the 20 th century Subject to continuous improvement 45 rpm singles, 33 rpm LP s Better styli, better transducers, better amplifiers, better tape, better loudspeakers Stereo Became a mature and dominant technology And, indeed, a large industry Music recording, distribution, retailing, Note that copying an analogue recording results in a reduction in quality CSCU9B2 7 CSCU9B2 8
3 Analogue Images & Video Mechanical assistance Albrecht Dürer ( ) used a grid to aid his reproductions. CSCU9B2 9 CSCU9B2 10 Technological image creation History of Photography? See Wikipedia for details Daguerrotype from 1839 Lincoln, 1846 Many innovations on its way to a pervasive mass technology Moving images _horse_gallop_animated_2.gif (1878) CSCU9B2 11 CSCU9B2 12
4 Moving images Victorian toys: zoetrope Film Multiple photography Initially travelling showmen, Later full commercial industry Needed industrialization of process, accurate machining etc. Places to show films Editing film Whole industry: Modern ideas of entertainment Documentaries and newsreels Imagination and illusion» Envelopment and escapism CSCU9B2 13 CSCU9B2 14 Snapshot: mid-1960 s analogue image industry Large industries: film, cameras, developers, consumer movies (super-8, and the developers), cinema, studios, production, distribution, showing: even photocopying (literally!). Picture-based printed media: newspapers, magazines, posters etc. Altogether a major industry pre-existed before anyone had really thought about using digital technology in this area Hollywood, studios in many other countries as well. CSCU9B2 15 Digital Formats As computers became faster and storage cheaper, it became sensible to store media in digital format This involves turning the physical (analogue) media into a long list of numbers which represented its form The form the media takes can be thought of as its signal. We will look at two digital signals image and sound CSCU9B2 16
5 Advantages of Digital Error free transmission and duplication Indefinitely copying without loss of quality Storage is generally safe and backups are easy to make Will the stored data last forever? See last lecture Storage of large quantities in small spaces Becomes better and better Fast transmission and sharing, including error correction Ease of searching, sorting, organising and editing Now hugely popular Image storage CSCU9B2 17 CSCU9B2 18 Electromagnetic Spectrum (1: visible is very small part 2: not all colours are present in the rainbow!) Images The analogue signal we record from an image is light specifically spectral content CSCU9B2 19 Digital formats do not store wavelength data, they use colour theory The most common format is called RGB CSCU9B2 20
6 RGB Colour Format Additive colour mixing produces colours by mixing light Mix colours of all wavelengths evenly and you get white (simplification) The additive primary colours are red, green and blue any colour can be made with the right combination of amounts of these three colours (simplification) So, to encode a colour, you need to store three values the amount of red, green, and blue it has CSCU9B Bit Colour You probably know that in computing, a byte is made up of 8 bits Each bit (binary digit) can take one of two values 0 or 1 With 8 bits, you can represent 2 8 = 256 different values, in this case the integers from 0 to 255 Standard 24 bit RGB colour uses 3 bytes to represent a colour, one for each primary colour using additive mixing CSCU9B2 22 RGB Colours 24 bit colour gives 256 x 256 x m different colours The eye is thought to be able to see about 10m different colours, so this should be fine for human consumption Smaller colour models are also used, for example 8 bit, either using a palette or 3 bits for red, 3 for green and 2 for blue: RGB Mixing Each of the three RGB components takes a value from 0 (no light of this colour) to 255 (full power!) 0,0,0 is black 255,255,255 is white 255,0,0 is bright red See (right) that red + green = yellow so 255,255,0 = yellow CSCU9B2 23 CSCU9B2 24
7 Using a value of less than 255 for any component reduces its quantity in the mix RGB Mixing Hexadecimal A small technical complication: Computer scientists don t always use base 10 You ve met binary base 2 Now here is base 16: 0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F,10,11 Base 16 is known as hexadecimal, or hex for short Each hex digit encodes 4 binary digits CSCU9B2 25 CSCU9B2 26 Hex and Colours 8 bit hex numbers run from 0 to FF So FF=255, FE=254, etc. RGB values are often represented in hex as a number from 0 to FF So white is FFFFFF, pale turquoise is AFEEEE, etc. Grey scales have all three values the same, e.g. ABABAB Web browsers expect colours to be specified in hex, as do some graphics programs Web Colour Names When web browsers and computer monitors could not display all 16m colours, there were a set of web safe colours defined. These don t tend to get used any more There is now a list of browser defined colours, given names such as Red (FF0000) and SpringGreen (00FF7F) CSCU9B2 27 CSCU9B2 28
8 RGBA - Transparency Representing an Image The RGBA colour model has a fourth component, known as the alpha (a) channel The alpha channel dictates the level of transparency in the colour This gives a 32 bit model 8 bits for alpha, plus the 24 for RGB Only some graphics formats can cope with alpha data (more later on this) CSCU9B2 29 Image is considered as an M by N array of picture elements Pixels M N <R, G, B> CSCU9B2 30 Representing an image cont d Mostly, images are assumed to be rectangular in shape, so they have a width and a height Each pixel has a colour represented with RGB The image is stored in memory or a file Image Files If you want to keep an image for long, you need to store it in a file You will need to store the numbers in such a way that image viewing software will know how to turn them back into an image This means that you will choose a format for your image CSCU9B2 31 CSCU9B2 32
9 Image File Formats This is not a new issue! There are lots of image file format standards A file format defines a number of things about how to convert from image to numbers and back to image again What makes the biggest difference is the compression method used More on this later Raster Images Images stored as a set of pixel values are known as raster images. Old-fashioned term from the days of cathode ray tubes This is the most common way to represent an image, particularly for photographs and many other graphics. Later we will look at an alternative vector graphics There are also mixtures of raster and vector There are also 3D image formats, which we won t be looking at CSCU9B2 33 CSCU9B2 34 Raster Image File Format When storing an image in a file, there are generally two types of data to store: Information about the image Dimensions and resolution Size in bytes Colour palette Etc. Pixel data in some format File Size and Quality Three things that make a difference to image quality and file size: Colour depth (number of bits used to encode colour 24 is very good) Resolution number of pixels in image. Obviously, more pixels = higher resolution Compression more on this later CSCU9B2 35 CSCU9B2 36
10 .BMP files A very simple file format,.bmp stores the RGB (and sometimes alpha) channels explicitly Also known as a Device Independent Bitmap The header starts with BM to show it is a bitmap file Pixel data starts in the lower left corner of the image, row by row.bmp Example Here is an enlarged image of 4 pixels Following the header, the file would contain: FFFF00 00FF00 FF FF Note, the spaces are for you to read it more easily, they don t appear in the file CSCU9B2 37 CSCU9B2 38 The Trouble with BMP Images can get quite big Let s say we want to print at 300dpi (dots per inch) A 6 x8 image would be 300x6 x 300x8 = over 4 million pixels, in 24 bit RGB that is nearly 13MB Not huge by today s standards, but slow if you are downloading a lot and not ideal if you have small memory cards CSCU9B2 39 Compression Image compression stores fewer numbers to represent an image Image compression may be: Lossless meaning that the re-created image is a perfect reproduction of the uncompressed original Lossy meaning that some information is thrown away (which may or may not be visible to the human eye) CSCU9B2 40
11 Lossless Compression Need to be able to reproduce the source image exactly Sensible for images on buttons, icons, etc. which are small anyway and need to look perfect Dictionary Encoding Based on a dictionary of pixel patterns found in the image Each pattern gets a code The codes are stored in the file To reproduce the image, look up each code and display the pattern it refers to An enhancement is to use variable length codes where common patterns have short codes CSCU9B2 41 CSCU9B2 42 Lossy Compression Reducing the colour depth can make an image file size smaller, as can scaling an image to smaller dimensions, but these acts do not really count as compression, though both are lossy Lossy compression generally relies on what we know about the human eye, and how it is better at seeing some things than others Subsampling The human visual system is more sensitive to changes in brightness than colour By keeping brightness information and discarding colour information, we can store less data and leave an image looking nearly as good as the original CSCU9B2 43 CSCU9B2 44
12 Scalability Many lossy compression algorithms allow the user to choose the amount of compression applied More compression = more loss = poorer image quality = smaller file Here is a jpeg image, compressed progressively from right to left Common Image Formats It pays to use the right image format at the right time Image quality Photo or low-colour graphics Animation Transparency Storage and transmission limitations Patents and freedom CSCU9B2 45 CC Michael Gäbler / Wikimedia Commons CSCU9B2 46 GIF 8 bit colour only Lossless compression (given the above) Can handle transparency Can be animated Was once patented, but this was challenged and it is no longer protected Good for web graphics PNG Created as open source version of GIF Supports 8 bit and 24 bit colours Transparency and animation Lossless (better than GIF, given colour depth) Generally preferred to GIF CSCU9B2 47 CSCU9B2 48
13 JPEG JPEG Lossy uses sub sampling compression Good for photos, bad for icons and illustrations No transparency nor animation Bad for text To probe further: see i/image_file_formats CSCU9B2 49 Next. Audio Formats CSCU9B2 50 Audio Formats Audio signals are produced by sound Sound can be thought of as a wave that travels from what ever makes the sound (the source) to whatever hears it (the receptor). Analogue sound through air causes a pressure wave, which means that the pressure at the receptor is continuously changing If the receptor is an ear, this continuous change in pressure is perceived as sound Plotting the Wave If we plot the change in pressure at the receptor over time, we see the familiar sound wave: CSCU9B2 51 CSCU9B2 52 CC Fillbit / Wikimedia Commons
14 Continuous Vs Digital Something we ignored when we looked at image formats: Analogue signals are continuous (usually) there is no number inside their operating range that they cannot take In theory, this allows for infinite accuracy Digital computers are not able to represent infinite ranges Binary Limitations Remember we said that 8 bit bytes can represent numbers from 0 to 255? More bits allow more numbers: 16 bits allows a range from 0 to 65,535, for example (the rate CDs are coded at) The number of bits used in representing the sound as a number is known as the word length, or resolution. CSCU9B2 53 CSCU9B2 54 Quantization The process of converting a continuous signal into a series of discrete values is known as quantization The accuracy lost by this process is called the quantization error Sampling Rate Just as the range of values are continuous, so is the signal over time To digitise a signal, we must sample at some fixed interval the samples are a series of snap shots Anything that happens between the samples is not recorded The higher the sampling rate, the better the sound quality CSCU9B2 55 CC Wikimedia Commons CSCU9B2 56
15 Sampling Rate Sound is made up of waves The pitch (bass to treble) of a note is largely determined by the frequency of the wave The frequency of a wave is the number of times it cycles in one second (measured in Hertz, Hz) High frequency waves require high frequency sampling To capture information at a frequency f Hz, you need to sample at a rate of more than 2f Hz This is known as the Nyquist sampling theorem. CSCU9B2 57 Audio Frequencies The (young!) human ear can hear sounds from around 20Hz to 20,000Hz (Hz = Hertz = cycles per second) CD quality sampling is at 44,100Hz, so is over the Nyquist rate for the human ear Of course, sound contains higher frequencies, but it doesn t matter that they are lost They do show up as a problem known as aliasing and need to be removed CSCU9B2 58 Sound Quality So, two things affect the quality of digital sound: Word length (accuracy of the representation) Sampling rate Usually 44,100Hz, but can be more or less These two factors combine to produce the usual measure of digital audio quality bit rate Bit Rate Bit rate describes the number of bits per second used to encode digital audio Stated in kilobits per second (1000 bits) It is simply the number of bits of the word length multiplied by the sampling frequency (times 2 for stereo) So 44,100Hz x 16bits x 2 = 1,411,200 = 1,411 kbit/s CSCU9B2 59 CSCU9B2 60
16 Compression You could use fewer bits per second if you dropped the sampling frequency or word length, but that would make a small reduction in size and a large reduction in sound quality Compression techniques can reduce the bit rate further (sometimes 10:1) without much loss of quality Compression Compression algorithms reduce the bit rate of an audio file while trying not to reduce sound quality Many algorithms for compressing sound, and they have a special name: codecs Coder/decoders Generally, the codec used will be specified by the file extension, e.g file.mp3 CSCU9B2 61 CSCU9B2 62 Compression Codecs Just as with image compression, there are two types of codec with respect to loss: Lossy codecs reduce the sound quality Lossless ones keep the sound quality Other things to consider about a codec Will hardware devices play it? Is it patent free? Does it include digital rights management (DRM)? Lossless Compression First, a quick mention of.wav files Microsoft s non-compressed audio format Can store 16bit 44.1kHz Sound quality is perfect, file size is large FLAC Free Lossless Audio Codec Patent and royalty free Typical 50% file size reduction Not all devices can play FLAC files CSCU9B2 63 CSCU9B2 64
17 Lossless Compression ALAC - Apple Lossless Audio Codec Proprietary owned by apple Works on all idevices Shares the.m4a file extension with Apple s lossy format, AAC Around 50% compression rate Lossy Compression Perhaps the best known MP3 Bit rates from 8 to 320 kbit/s Sampling rate up to 48 khz Patented some issues with Firefox, for example DRM rarely used Widely supported by hardware and software CSCU9B2 65 CSCU9B2 66 Advanced Audio Coding (AAC) Designed to replace MP3 Better audio quality for same bit rates Chosen by Apple for itunes store format Includes DRM restrictions FairPlay Widely supported by software, smart phones, games consoles, etc. Codec of choice on YouTube Windows Media Audio Owned by Microsoft Lossy and Lossless versions + one for voice 48 khz, up to 768 kbit/s DRM support Not as widely supported as some other formats (need to convert it to AAC to play on idevices, for example) CSCU9B2 67 CSCU9B2 68
18 Vorbis Ogg Ogg is a freeware audio codec with no patents and no licence fees Can sample up to 200 khz Format used in HTML5 No DRM Well supported by hardware, phones, etc. Finally. Video Formats CSCU9B2 69 CSCU9B2 70 Video Codecs Digital video overview: Video is a series of images shown in order at a speed the creates the illusion of movement It also often has an audio track We have already looked at digital image and audio compression We will now have a quick look at video Movie is made up of a sequence of still images Each still image could be coded as for images But this would need a lot of space Some stills are coded this way Rest coded by differencing Deltas Key Frames CSCU9B2 71 CSCU9B2 72
19 WMV Windows Media Video Owned by Microsoft Can support DRM Software support in Windows Media Player, RealPlayer and others Some hardware support e.g. Windows mobile devices File extension is.wmv H.264 / MPEG-4 AVC AVC = Advanced Video Coding One of the codec standards for Blu-ray Used by YouTube, Adobe Flash, itunes, and various HDTV Used on idevices too Patent protected arguments about use in HTML5 abound File extension is usually.mp4 or.avc CSCU9B2 73 CSCU9B2 74 Flash Video One of the most common online video format Plays in the Adobe Flash Player Supports a variety of codecs including H.264 Not supported by idevices File extensions are.flv,.f4v Also can be contained in.swf files CSCU9B2 75 Theora Free lossy compression format Same organisation that brought you.ogg audio Supported by HTML5 Patent free, open source No idevice support Many software packages will play it File extension is.ogg or.ogv CSCU9B2 76
20 Summary Images, audio and video all have in common: A wide choice of file format and compression methods, quality and file size Issues of quantization, resolution and sampling rate A choice of free or patented methods Limitations in which software and devices will recognise them CSCU9B2 77
Standard File Formats
Standard File Formats Introduction:... 2 Text: TXT and RTF... 4 Grapics: BMP, GIF, JPG and PNG... 5 Audio: WAV and MP3... 8 Video: AVI and MPG... 11 Page 1 Introduction You can store many different types
More informationElementary Computing CSC 100. M. Cheng, Computer Science
Elementary Computing CSC 100 1 Graphics & Media Scalable Outline & Bit- mapped Fonts Binary Number Representation & Text Pixels, Colors and Resolution Sound & Digital Audio Film & Digital Video Data Compression
More informationLecture #3: Digital Music and Sound
Lecture #3: Digital Music and Sound CS106E Spring 2018, Young In this lecture we take a look at how computers represent music and sound. One very important concept we ll come across when studying digital
More informationIntroduction to Computer Science (I1100) Data Storage
Data Storage 145 Data types Data comes in different forms Data Numbers Text Audio Images Video 146 Data inside the computer All data types are transformed into a uniform representation when they are stored
More information计算原理导论. Introduction to Computing Principles 智能与计算学部刘志磊
计算原理导论 Introduction to Computing Principles 天津大学 智能与计算学部刘志磊 Analog The world is basically analog What does that mean? "Signal" is a varying wave over time e.g. sound as a running example here How Does
More informationFundamental of Digital Media Design. Introduction to Audio
Fundamental of Digital Media Design Introduction to Audio by Noraniza Samat Faculty of Computer Systems & Software Engineering noraniza@ump.edu.my OER Fundamental of Digital Media Design by Noraniza Samat
More informationMultimedia applications
applications László Kálmán 1 Csaba Oravecz 1 Péter Szigetvári 2 1 Research Institute for Linguistics Hungarian Academy of Sciences 2 Department of English Linguistics Eötvös Loránd University Lecture 9.
More informationUNDERSTANDING MUSIC & VIDEO FORMATS
ComputerFixed.co.uk Page: 1 Email: info@computerfixed.co.uk UNDERSTANDING MUSIC & VIDEO FORMATS Are you confused with all the different music and video formats available? Do you know the difference between
More informationAdvanced High Graphics
VISUAL MEDIA FILE TYPES JPG/JPEG: (Joint photographic expert group) The JPEG is one of the most common raster file formats. It s a format often used by digital cameras as it was designed primarily for
More informationLecture 19 Media Formats
Revision IMS2603 Information Management in Organisations Lecture 19 Media Formats Last week s lectures looked at MARC as a specific instance of complex metadata representation and at Content Management
More informationExample 1: Denary = 1. Answer: Binary = (1 * 1) = 1. Example 2: Denary = 3. Answer: Binary = (1 * 1) + (2 * 1) = 3
1.1.1 Binary systems In mathematics and digital electronics, a binary number is a number expressed in the binary numeral system, or base-2 numeral system, which represents numeric values using two different
More information3.01C Multimedia Elements and Guidelines Explore multimedia systems, elements and presentations.
3.01C Multimedia Elements and Guidelines 3.01 Explore multimedia systems, elements and presentations. Multimedia Fair Use Guidelines Guidelines for using copyrighted multimedia elements include: Text Motion
More informationMEDIA RELATED FILE TYPES
MEDIA RELATED FILE TYPES Data Everything on your computer is a form of data or information and is ultimately reduced to a binary language of ones and zeros. If all data stayed as ones and zeros the information
More informationCS 074 The Digital World. Digital Audio
CS 074 The Digital World Digital Audio 1 Digital Audio Waves Hearing Analog Recording of Waves Pulse Code Modulation and Digital Recording CDs, Wave Files, MP3s Editing Wave Files with BinEd 2 Waves A
More informationImage Types Vector vs. Raster
Image Types Have you ever wondered when you should use a JPG instead of a PNG? Or maybe you are just trying to figure out which program opens an INDD? Unless you are a graphic designer by training (like
More informationDigital Media. Daniel Fuller ITEC 2110
Digital Media Daniel Fuller ITEC 2110 Daily Question: Which statement is True? 5 + 5 = 10 1 + 1 = 10 F + 1 = 10 Email answer to DFullerDailyQuestion@gmail.com Subject Line: ITEC2110-26 First, some mac
More informationMULTIMEDIA AND CODING
07 MULTIMEDIA AND CODING WHAT MEDIA TYPES WE KNOW? TEXTS IMAGES SOUNDS MUSIC VIDEO INTERACTIVE CONTENT Games Virtual reality EXAMPLES OF MULTIMEDIA MOVIE audio + video COMPUTER GAME audio + video + interactive
More informationCHAPTER 10: SOUND AND VIDEO EDITING
CHAPTER 10: SOUND AND VIDEO EDITING What should you know 1. Edit a sound clip to meet the requirements of its intended application and audience a. trim a sound clip to remove unwanted material b. join
More informationData Representation From 0s and 1s to images CPSC 101
Data Representation From 0s and 1s to images CPSC 101 Learning Goals After the Data Representation: Images unit, you will be able to: Recognize and translate between binary and decimal numbers Define bit,
More informationMultimedia Technology
Multimedia Application An (usually) interactive piece of software which communicates to the user using several media e.g Text, graphics (illustrations, photos), audio (music, sounds), animation and video.
More informationCompression; Error detection & correction
Compression; Error detection & correction compression: squeeze out redundancy to use less memory or use less network bandwidth encode the same information in fewer bits some bits carry no information some
More informationCompression; Error detection & correction
Compression; Error detection & correction compression: squeeze out redundancy to use less memory or use less network bandwidth encode the same information in fewer bits some bits carry no information some
More informationGeneral Computing Concepts. Coding and Representation. General Computing Concepts. Computing Concepts: Review
Computing Concepts: Review Coding and Representation Computers represent all information in terms of numbers ASCII code: Decimal number 65 represents A RGB: (255,0,0) represents the intense red Computers
More informationCHAPTER 2 - DIGITAL DATA REPRESENTATION AND NUMBERING SYSTEMS
CHAPTER 2 - DIGITAL DATA REPRESENTATION AND NUMBERING SYSTEMS INTRODUCTION Digital computers use sequences of binary digits (bits) to represent numbers, letters, special symbols, music, pictures, and videos.
More informationData Representation. Reminders. Sound What is sound? Interpreting bits to give them meaning. Part 4: Media - Sound, Video, Compression
Data Representation Interpreting bits to give them meaning Part 4: Media -, Video, Compression Notes for CSC 100 - The Beauty and Joy of Computing The University of North Carolina at Greensboro Reminders
More information255, 255, 0 0, 255, 255 XHTML:
Colour Concepts How Colours are Displayed FIG-5.1 Have you looked closely at your television screen recently? It's in full colour, showing every colour and shade that your eye is capable of seeing. And
More informationBinary representation and data
Binary representation and data Loriano Storchi loriano@storchi.org http:://www.storchi.org/ Binary representation of numbers In a positional numbering system given the base this directly defines the number
More informationMultimedia Content. Web Architecture and Information Management [./] Spring 2009 INFO (CCN 42509) Contents. Erik Wilde, UC Berkeley School of
Contents Multimedia Content Contents Web Architecture and Information Management [./] Spring 2009 INFO 190-02 (CCN 42509) Erik Wilde, UC Berkeley School of Information [http://creativecommons.org/licenses/by/3.0/]
More information3 Data Storage 3.1. Foundations of Computer Science Cengage Learning
3 Data Storage 3.1 Foundations of Computer Science Cengage Learning Objectives After studying this chapter, the student should be able to: List five different data types used in a computer. Describe how
More informationDigital Audio. Amplitude Analogue signal
Digital Audio The sounds that we hear are air molecules vibrating in a wave pattern. These sound waves are measured by our ear drums and processed in our brain. As computers are digital machines, sound
More informationMicrocontroller Compatible Audio File Conversion
Microcontroller Compatible Audio File Conversion Created by Mike Barela Last updated on 2018-06-07 09:10:45 PM UTC Guide Contents Guide Contents Convert Sound Files in Audacity Audacity Download Audacity
More information1.6 Graphics Packages
1.6 Graphics Packages Graphics Graphics refers to any computer device or program that makes a computer capable of displaying and manipulating pictures. The term also refers to the images themselves. A
More informationComputing in the Modern World
Computing in the Modern World BCS-CMW-7: Data Representation Wayne Summers Marion County October 25, 2011 There are 10 kinds of people in the world: those who understand binary and those who don t. Pre-exercises
More informationAET 1380 Digital Audio Formats
AET 1380 Digital Audio Formats Consumer Digital Audio Formats CDs --44.1 khz, 16 bit Television 48 khz, 16bit DVD 96 khz, 24bit How many more measurements does a DVD take? Bit Rate? Sample rate? Is it
More informationBits, bytes, binary numbers, and the representation of information
Bits, bytes, binary numbers, and the representation of information computers represent, process, store, copy, and transmit everything as numbers hence "digital computer" the numbers can represent anything
More informationCDs & DVDs: Different Types of Disk Explained
CDs & DVDs: Different Types of Disk Explained C 200 / 1 Don t Waste Money Buying the Wrong Type Find Out Which Disks Your PC Can Use! Your PC almost certainly has at least one CD/DVD drive. In its most
More informationWhat is Data Storage?
What is Data Storage? When we talk about storing data, we mean putting the data in a known place. We can later come back to that place and get our data back again. Writing data or saving data are other
More informationRepresenting Graphical Data
Representing Graphical Data Chapman & Chapman, chapters 3,4,5 Richardson 1 Graphics in IT82 What does computer graphics cover? IT82 Input, output, and representation of graphical data Creation of graphics
More informationG64PMM - Lecture 3.2. Analogue vs Digital. Analogue Media. Graphics & Still Image Representation
G64PMM - Lecture 3.2 Graphics & Still Image Representation Analogue vs Digital Analogue information Continuously variable signal Physical phenomena Sound/light/temperature/position/pressure Waveform Electromagnetic
More informationDigitization of Multimedia Elements
MULTI-MEDIA PRODUCTION Basic Multimedia Elements i. Text ii. Graphics iii. Sound iv. Video v. Animations Digitization of Multimedia Elements Analogue and digital signals Analogue signal: a continuous signal
More informationApplication of Huffman Coding in Lossless Video Compression
Application of Huffman Coding in Lossless Video Compression Mahessa Ramadhana - 13511077 Program Studi Teknik Informatika Sekolah Teknik Elektro dan Informatika Institut Teknologi Bandung, Jl. Ganesha
More informationUnit 2 Digital Information. Chapter 1 Study Guide
Unit 2 Digital Information Chapter 1 Study Guide 2.5 Wrap Up Other file formats Other file formats you may have encountered or heard of include:.doc,.docx,.pdf,.mp4,.mov The file extension you often see
More informationMultimedia on the Web
Multimedia on the Web Graphics in web pages Downloading software & media Digital photography JPEG & GIF Streaming media Macromedia Flash Graphics in web pages Graphics are very popular in web pages Graphics
More informationImage and video processing
Image and video processing Digital video Dr. Pengwei Hao Agenda Digital video Video compression Video formats and codecs MPEG Other codecs Web video - 2 - Digital Video Until the arrival of the Pentium
More informationCHAPTER 6 Audio compression in practice
CHAPTER 6 Audio compression in practice In earlier chapters we have seen that digital sound is simply an array of numbers, where each number is a measure of the air pressure at a particular time. This
More informationVarious text document, image and media file formats and how to select and convert between them.
Various text document, image and media file formats and how to select and convert between them. Plain text Rich Text Format.DOC.DOCX No fancy formatting but can be read by any computer. Use Notepad or
More information(Refer Slide Time 00:17) Welcome to the course on Digital Image Processing. (Refer Slide Time 00:22)
Digital Image Processing Prof. P. K. Biswas Department of Electronics and Electrical Communications Engineering Indian Institute of Technology, Kharagpur Module Number 01 Lecture Number 02 Application
More informationAudio for Everybody. OCPUG/PATACS 21 January Tom Gutnick. Copyright by Tom Gutnick. All rights reserved.
Audio for Everybody OCPUG/PATACS 21 January 2017 Copyright 2012-2017 by Tom Gutnick. All rights reserved. Tom Gutnick Session overview Digital audio properties and formats ADC hardware Audacity what it
More informationData Representation 1
1 Data Representation Outline Binary Numbers Adding Binary Numbers Negative Integers Other Operations with Binary Numbers Floating Point Numbers Character Representation Image Representation Sound Representation
More informationOptimizing Audio for Mobile Development. Ben Houge Berklee College of Music Music Technology Innovation Valencia, Spain
Optimizing Audio for Mobile Development Ben Houge Berklee College of Music Music Technology Innovation Valencia, Spain Optimizing Audio Different from movies or CD s Data size vs. CPU usage For every generation,
More informationProfessor Laurence S. Dooley. School of Computing and Communications Milton Keynes, UK
Professor Laurence S. Dooley School of Computing and Communications Milton Keynes, UK How many bits required? 2.4Mbytes 84Kbytes 9.8Kbytes 50Kbytes Data Information Data and information are NOT the same!
More informationLogo & Icon. Fit Together Logo (color) Transome Logo (black and white) Quick Reference Print Specifications
GRAPHIC USAGE GUIDE Logo & Icon The logo files on the Fit Together logos CD are separated first by color model, and then by file format. Each version is included in a small and large size marked by S or
More informationDigital Media. Lecture 2: SemesterOverview. Georgia Gwinnett College School of Science and Technology Dr. Mark Iken
Digital Media Lecture 2: SemesterOverview Georgia Gwinnett College School of Science and Technology Dr. Mark Iken Refer to Supplemental text: Counting like an alien Networking issues Sound and Sampling
More informationCompressed Audio Demystified by Hendrik Gideonse and Connor Smith. All Rights Reserved.
Compressed Audio Demystified Why Music Producers Need to Care About Compressed Audio Files Download Sales Up CD Sales Down High-Definition hasn t caught on yet Consumers don t seem to care about high fidelity
More informationDifferent File Types and their Use
Different File Types and their Use.DOC (Microsoft Word Document) Text Files A DOC file is a Word processing document created by Microsoft Word, a word processor included with all versions of Microsoft
More informationA Digital Audio Primer
Conversion of Sound Wave to Analog Signal A Digital Audio Primer Many people don t care about the technology behind their stereo system. As long as it sounds good and they can press a button and listen
More informationGRAPHIC FILE FORMATS / SOFTWARE SELECTION / SOFTWARE COMPATIBILITY
HIGHER COMPUTING COMPUTER SYSTEMS COMPUTER SOFTWARE GRAPHIC FILE FORMATS / SOFTWARE SELECTION / SOFTWARE COMPATIBILITY SUCCESS CRITERIA I can describe the standard file formats for graphics files: Jpeg
More informationParts are adapted from Windows 98 by Mark Twain Media, Inc. A Computer System has Hardware and Software
Parts are adapted from Windows 98 by Mark Twain Media, Inc. A Computer System has Hardware and Software All the parts--monitor, printer, hard drive, etc.-- cables, cabinets, and programs that make a computer
More informationLossy compression. CSCI 470: Web Science Keith Vertanen
Lossy compression CSCI 470: Web Science Keith Vertanen Digital audio Overview Sampling rate Quan5za5on MPEG audio layer 3 (MP3) JPEG s5ll images Color space conversion, downsampling Discrete Cosine Transform
More informationData Representation. Data is more than just numbers! Representations of Text ASCII. Interpreting bits to give them meaning.
Data Representation Interpreting bits to give them meaning Part 2: Media Text, Web Pages,, /Music, Video Notes for CSC 100 - The Beauty and Joy of Computing The University of North Carolina at Greensboro
More informationChapter 5.5 Audio Programming
Chapter 5.5 Audio Programming Audio Programming Audio in games is more important than ever before 2 Programming Basic Audio Most gaming hardware has similar capabilities (on similar platforms) Mostly programming
More informationDigiPoints Volume 1. Student Workbook. Module 8 Digital Compression
Digital Compression Page 8.1 DigiPoints Volume 1 Module 8 Digital Compression Summary This module describes the techniques by which digital signals are compressed in order to make it possible to carry
More informationGraphics File Formats
1 Graphics File Formats Why have graphics file formats? What to look for when choosing a file format A sample tour of different file formats, including bitmap-based formats vector-based formats metafiles
More informationDigital Audio Basics
CSC 170 Introduction to Computers and Their Applications Lecture #2 Digital Audio Basics Digital Audio Basics Digital audio is music, speech, and other sounds represented in binary format for use in digital
More informationIMAGE COMPRESSION USING FOURIER TRANSFORMS
IMAGE COMPRESSION USING FOURIER TRANSFORMS Kevin Cherry May 2, 2008 Math 4325 Compression is a technique for storing files in less space than would normally be required. This in general, has two major
More informationVideo Compression Secrets - Smaller Files, Better Quality UPDATED (Oct 15)
Video Compression Secrets - Smaller Files, Better Quality UPDATED (Oct 15) by Stephen Haskin, October 19, 2015 The best codec to keep file sizes small is Windows Media (WMV). Microsoft has done an excellent
More informationFlying Start AS Computer Science. September 2015
Flying Start AS Computer Science September 2015 Name: To your first AS Computing lesson, you will need to bring: 1. A folder with dividers An A4 ring binder with labelled A4 dividers would be ideal. The
More informationObjectives. Connecting with Computer Science 2
Objectives Learn why numbering systems are important to understand Refresh your knowledge of powers of numbers Learn how numbering systems are used to count Understand the significance of positional value
More informationIntroducing working with sounds in Audacity
Introducing working with sounds in Audacity A lot of teaching programs makes it possible to add sound to your production. The student can either record her or his own voice and/or add different sound effects
More informationData encoding. Lauri Võsandi
Data encoding Lauri Võsandi Binary data Binary can represent Letters of alphabet, plain-text files Integers, floating-point numbers (of finite precision) Pixels, images, video Audio samples Could be stored
More information1. Introduction to Multimedia
Standard:11 1. Introduction to Multimedia Communication is an integral part of our life. We use various means of communication like radio, newspaper, television, theatre, movies, internet and others. These
More informationCpSc 101, Fall 2015 Lab7: Image File Creation
CpSc 101, Fall 2015 Lab7: Image File Creation Goals Construct a C language program that will produce images of the flags of Poland, Netherland, and Italy. Image files Images (e.g. digital photos) consist
More informationBMP file format. Contents. Pixel storage. The BMP file format, sometimes called bitmap. or DIB file format (for device-independent
1 of 7 BMP file format From Wikipedia, the free encyclopedia Windows Bitmap The BMP file format, sometimes called bitmap File extension:.bmp or.dib or DIB file format (for device-independent MIME type:
More informationGerald's Column by Gerald Fitton
Gerald's Column by Gerald Fitton I've had quite a lot of feedback this month about some recent and some long ago articles; I wasn't sure whether to do a PipeDream/Fireworkz article, a domain name or email
More informationComputer Graphics Fundamentals. Jon Macey
Computer Graphics Fundamentals Jon Macey jmacey@bournemouth.ac.uk http://nccastaff.bournemouth.ac.uk/jmacey/ 1 1 What is CG Fundamentals Looking at how Images (and Animations) are actually produced in
More informationWeb graphics. Introduction
Web graphics Introduction Role of Web Graphics Role of Web Graphics Although web designers could build a site without graphics, most users would not readily recognize a collection of bare pages as a cohesive
More information1/27/2013. Outline. Adding images to your site. Images and Objects INTRODUCTION TO WEB DEVELOPMENT AND HTML
Outline INTRODUCTION TO WEB DEVELOPMENT AND HTML Images and Objects: Adding images to your site Adding Objects with Using Images as Links Image Maps Exercise Lecture 05 - Spring 2013 Adding images
More informationIntroducing Audio Signal Processing & Audio Coding. Dr Michael Mason Senior Manager, CE Technology Dolby Australia Pty Ltd
Introducing Audio Signal Processing & Audio Coding Dr Michael Mason Senior Manager, CE Technology Dolby Australia Pty Ltd Overview Audio Signal Processing Applications @ Dolby Audio Signal Processing Basics
More informationPrentice Hall. Learning Microsoft PowerPoint , (Weixel et al.) Arkansas Multimedia Applications I - Curriculum Content Frameworks
Prentice Hall Learning Microsoft PowerPoint 2007 2008, (Weixel et al.) C O R R E L A T E D T O Arkansas Multimedia s I - Curriculum Content Frameworks Arkansas Multimedia s I - Curriculum Content Frameworks
More informationNUMBERS AND DATA REPRESENTATION. Introduction to Computer Engineering 2015 Spring by Euiseong Seo
NUMBERS AND DATA REPRESENTATION Introduction to Computer Engineering 2015 Spring by Euiseong Seo Chapter Goals Distinguish among categories of numbers Describe positional notation Convert numbers in other
More informationVideo. Add / edit video
Video Videos greatly support learning in an e-earning setting. It is a rather complex topic though, due to the variety of formats, codecs, containers and combination of operating systems and browsers.
More informationAmazing Audacity: Session 1
Online 2012 Amazing Audacity: Session 1 Katie Wardrobe Midnight Music The Audacity Screen...3 Import audio (a song or SFX)...3 Before we start... 3 File formats... 3 What s the different between WAV and
More informationThe Gullibility of Human Senses
The Gullibility of Human Senses Three simple tricks for producing LBSC 690: Week 9 Multimedia Jimmy Lin College of Information Studies University of Maryland Monday, April 2, 2007 Images Video Audio But
More informationIntroducing Audio Signal Processing & Audio Coding. Dr Michael Mason Snr Staff Eng., Team Lead (Applied Research) Dolby Australia Pty Ltd
Introducing Audio Signal Processing & Audio Coding Dr Michael Mason Snr Staff Eng., Team Lead (Applied Research) Dolby Australia Pty Ltd Introducing Audio Signal Processing & Audio Coding 2013 Dolby Laboratories,
More informationPart 1 of 4. MARCH
Presented by Brought to You by Part 1 of 4 MARCH 2004 www.securitysales.com A1 Part1of 4 Essentials of DIGITAL VIDEO COMPRESSION By Bob Wimmer Video Security Consultants cctvbob@aol.com AT A GLANCE Compression
More informationRevision Guide. Creative Imedia R081
Revision Guide Creative Imedia R081 Creative R081 revision Guide Overview of the unit You must be able to describe the process of creating pre-production documents and the role they play in the development
More information21st-Century Image and Data Exchange Standards
Course IN22-1 21st-Century Image and Data Exchange Standards Peter Sheerin Dec 3, 2003 02:00 PM 03:30 PM 1 2 Why do Formats Matter? Image quality Interoperability Capabilities/features Alpha channel/transparency
More informationWhat Do I Really Need to Know about itunes? COPYRIGHTED MATERIAL
1 What Do I Really Need to Know about itunes? COPYRIGHTED MATERIAL 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Managing a library of music and other media content can be a challenging task, and itunes is a powerful
More informationGCSE Computing. Revision Pack TWO. Data Representation Questions. Name: /113. Attempt One % Attempt Two % Attempt Three %
GCSE Computing Revision Pack TWO Data Representation Questions Name: /113 Attempt One % Attempt Two % Attempt Three % Areas of Strength Areas for Development 1. Explain how ASCII is used to represent text
More informationWelcome. Web Authoring: HTML - Advanced Topics & Photo Optimisation (Level 3) Richard Hey & Barny Baggs
Welcome Web Authoring: HTML - Advanced Topics & Photo Optimisation (Level 3) Richard Hey & Barny Baggs Health and Safety Course Information General Information Objectives To understand the need for photo
More informationImportant Encoder Settings for Your Live Stream
Important Encoder Settings for Your Live Stream Being able to stream live video over the Internet is a complex technical endeavor. It requires a good understanding of a number of working parts. That s
More informationPrinciples of Audio Coding
Principles of Audio Coding Topics today Introduction VOCODERS Psychoacoustics Equal-Loudness Curve Frequency Masking Temporal Masking (CSIT 410) 2 Introduction Speech compression algorithm focuses on exploiting
More informationHow Analog and Digital Recording and CDs Work Adapted from by Marshall Brain
How Analog and Digital Recording and CDs Work Adapted from www.howstuffworks.com by Marshall Brain In the Beginning: Etching Tin Thomas Edison is credited with creating the first device for recording and
More informationFrequently Asked Questions about Text and Graphics
1 Frequently Asked Questions about Text and Graphics 1. What is a font? A font is a set of printable or displayable text characters that are in a specific style and size. The type design for a set of fonts
More informationAdobe Graphics Software
Adobe Graphics Software Untitled-1.indd 1 20.11.2015 13:05:28 Untitled-1.indd 2 20.11.2015 13:05:28 3 Recent versions have brought in functionality for working with 3D designs, though the program still
More informationHTML/XML. XHTML Authoring
HTML/XML XHTML Authoring Adding Images The most commonly used graphics file formats found on the Web are GIF, JPEG and PNG. JPEG (Joint Photographic Experts Group) format is primarily used for realistic,
More informationImage creation with PHP
Image creation with PHP By Kore Nordmann PHP Unconference Hamburg 25.04.08 About me Kore Nordmann Studying computer science at the University Dortmund Working for ez systems on ez components Maintainer
More informationInteractive Multimedia. Multimedia and the World Wide Web
Interactive Multimedia Multimedia and the World Wide Web Multimedia and WWW What is Multimedia? why is it important? Who needs to know about Multimedia? Interactive Multimedia hypermedia, hypertext media
More informationSkill Area 214: Use a Multimedia Software. Software Application (SWA)
Skill Area 214: Use a Multimedia Application (SWA) Skill Area 214: Use a Multimedia 214.4 Produce Audio Files What is digital audio? Audio is another meaning for sound. Digital audio refers to a digital
More informationRepetition 1st lecture
Repetition 1st lecture Human Senses in Relation to Technical Parameters Multimedia - what is it? Human senses (overview) Historical remarks Color models RGB Y, Cr, Cb Data rates Text, Graphic Picture,
More information