1 The League for Innovation in the Community College CIT 2003 102E, Convention Center – Monday, October 20, 2003 9:15 AM – 10:15 AM Digital Media Formats: What Faculty and Students Need-To-Know (a work in progress) Nancy Mallory Professor, Visual and Performing Arts Dale Mallory Assistant Vice President, Educational Technology Services Brett Thompson Director, Network Systems and Applications Development Monroe Community College - Rochester, NY
Transcript
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The League for Innovation in the Community CollegeCIT 2003
102E, Convention Center – Monday, October 20, 2003 9:15 AM – 10:15 AM
Digital Media Formats: What Faculty and Students
Need-To-Know (a work in progress)
Nancy MalloryProfessor,
Visual and Performing Arts
Dale MalloryAssistant Vice President,
Educational Technology Services
Brett ThompsonDirector,
Network Systems and Applications Development
Monroe Community College - Rochester, NY
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OverviewOverview
IntroductionsIntroductions
Why – Digital Media FormatsWhy – Digital Media Formats
What – Digital Media FormatsWhat – Digital Media Formats
Wrap-upWrap-up
SummarySummary
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Who are WE?Who are WE?
Nancy Mallory Nancy Mallory (([email protected]@monroecc.edu))ProfessorProfessorVisual and Performing ArtsVisual and Performing Arts
Brett Thompson Brett Thompson (([email protected]@monroecc.edu) ) DirectorDirectorNetwork Systems and Applications DevelopmentNetwork Systems and Applications DevelopmentEducational Technology ServicesEducational Technology Services
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Who are YOU?Who are YOU?
How many?How many? Network ManagersNetwork Managers FacultyFaculty AdministratorsAdministrators Security StaffSecurity Staff Video Production StaffVideo Production Staff Other…Other…
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Why do I need to know this stuff?Why do I need to know this stuff?
File formats are more than just three letter File formats are more than just three letter words.words.
Students may be more computer savvy.Students may be more computer savvy.
Internet growthInternet growth Students sharing and swapping files across Students sharing and swapping files across
the planet.the planet.
Students are doing more “stuff” that Students are doing more “stuff” that utilizes larger file sizes on stand-alone utilizes larger file sizes on stand-alone PC’s. PC’s.
Media technology convergence.Media technology convergence.
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Why do I need to know this stuff?Why do I need to know this stuff?
Most students do not have the skill sets: Most students do not have the skill sets: layout and design; color theory; recording layout and design; color theory; recording techniques; audio and video editing; techniques; audio and video editing; computer knowledge; photography. computer knowledge; photography.
Most students do not have computer or Most students do not have computer or network theory.network theory.
Students are using computers without Students are using computers without fundamental knowledge.fundamental knowledge.
Students don’t understand the Students don’t understand the ramifications of their actions.ramifications of their actions.
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Examples...(or why I need to know)Examples...(or why I need to know)
CDA files – not easily read by editing CDA files – not easily read by editing software – AVID/Gold Wave – CDA files software – AVID/Gold Wave – CDA files are not really files but are tracks on are not really files but are tracks on conventional audio CD’s being conventional audio CD’s being represented as files by Windows.represented as files by Windows.Difficulties Burning CD’s and DVD’s – best Difficulties Burning CD’s and DVD’s – best practice is to stage to hard drive before practice is to stage to hard drive before burning (depends on media format and burning (depends on media format and target platform).target platform).Working with files – size matters (e.g. Working with files – size matters (e.g. trying to save large file to floppy).trying to save large file to floppy).
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Examples...(or why I need to know)Examples...(or why I need to know)
Knowing your media storage limitations Knowing your media storage limitations floppy, 100 Megabyte Zip, 250 Megabyte floppy, 100 Megabyte Zip, 250 Megabyte Zip, CD, DVD single layer, DVD dual layer, Zip, CD, DVD single layer, DVD dual layer, hard drive free space.hard drive free space.Know your image sizes and how to re-Know your image sizes and how to re-size.size.
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Examples...(or why I need to know)Examples...(or why I need to know)
Video editing software and its implications Video editing software and its implications (New AVID available for home users now (New AVID available for home users now wanting to send files and images to wanting to send files and images to friends/family).friends/family).
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Examples...(or why I need to know)Examples...(or why I need to know)
Different ISP’s have different file size Different ISP’s have different file size limitations or quotas:limitations or quotas: Inbound and/or outbound e-mail attachments Inbound and/or outbound e-mail attachments
usually limited to 5 megabytes or less. usually limited to 5 megabytes or less. Most e-mail systems also impose an overall Most e-mail systems also impose an overall
quota on the amount of mail they can hold quota on the amount of mail they can hold (e.g. free services such as Yahoo, MSN, etc, (e.g. free services such as Yahoo, MSN, etc, have very small quotas of 2-3 megabytes).have very small quotas of 2-3 megabytes).
Many e-mail systems also block file types Many e-mail systems also block file types which are most prone to carry trojans and which are most prone to carry trojans and viruses such as the following file types: exe, viruses such as the following file types: exe, pif, scr, bat, and vbs.pif, scr, bat, and vbs.
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Examples...(or why I need to know)Examples...(or why I need to know)
Senders/publishers need to plan for the Senders/publishers need to plan for the lowest common denominator in terms of lowest common denominator in terms of bandwidth speed for their viewers.bandwidth speed for their viewers.
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Examples…(or why I need to know)Examples…(or why I need to know)
Information on demand Information on demand Students on campus have faster connections Students on campus have faster connections
than at home.than at home. Students want high speed access to Students want high speed access to
information at home.information at home. Residence halls etc. what you can deliver on Residence halls etc. what you can deliver on
campus on a closed network is 10 times faster campus on a closed network is 10 times faster than at home because ISP connections are all than at home because ISP connections are all different.different.
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Examples…(or why I need to know)Examples…(or why I need to know) Bandwidth limiting is common on many ISP Bandwidth limiting is common on many ISP
and college campuses. This technology and college campuses. This technology prioritizes traffic based on the Internet service prioritizes traffic based on the Internet service being used and can significantly affect the being used and can significantly affect the speed of downloads. Some services such as speed of downloads. Some services such as Kazaa, Video Streaming, etc. may be severely Kazaa, Video Streaming, etc. may be severely limited to reserve bandwidth for business limited to reserve bandwidth for business critical and general web browsing activities.critical and general web browsing activities.
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What I need to Know: What I need to Know: Digital Media FormatsDigital Media Formats
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Digital Media FormatsDigital Media Formats
Digital Media File FormatsDigital Media File Formats A collection of file formats used commonly to A collection of file formats used commonly to
represent various real-world media types represent various real-world media types digitally.digitally.
So what’s a file?So what’s a file?
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Digital Media FormatsDigital Media Formats
FileFileA collection of related data stored together A collection of related data stored together on or in some type of storage media.on or in some type of storage media. ExamplesExamples
Text on paperText on paper
Electronic text stored on a computer’s diskElectronic text stored on a computer’s disk
Photographic elements stored in a digital camera.Photographic elements stored in a digital camera.
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Digital Media FormatsDigital Media Formats
File FormatsFile FormatsSpecifications that define the layout or Specifications that define the layout or format of data within a file such that data format of data within a file such that data can be successfully shared and can be successfully shared and interpreted among multiple platforms. On interpreted among multiple platforms. On computers these are sometimes computers these are sometimes represented by file name extensions.represented by file name extensions. ExamplesExamples
Resume, Business LetterResume, Business Letter
Microsoft Word Document (*.doc)Microsoft Word Document (*.doc)
Microsoft Excel Document (*.xls)Microsoft Excel Document (*.xls)
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Digital Media FormatsDigital Media Formats
Digital Media File FormatsDigital Media File FormatsFile formats designed to represent File formats designed to represent common digital media types, such as:common digital media types, such as: PhotographsPhotographs Computer Art, Business Drawings, CADComputer Art, Business Drawings, CAD VideoVideo Digital Music (e.g. MIDI)Digital Music (e.g. MIDI) AudioAudio AnimationsAnimations Hybrids or combinations of the above.Hybrids or combinations of the above.
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Digital Media FormatsDigital Media Formats
Digital Media File Formats FactsDigital Media File Formats Facts For each type of media there are many, For each type of media there are many,
sometimes hundreds, of file formats used in sometimes hundreds, of file formats used in the marketplace.the marketplace.
Of these, there are popular formats which are Of these, there are popular formats which are supported by numerous applications as well supported by numerous applications as well as obscure formats supported by industry as obscure formats supported by industry specific applications. specific applications.
Digital Media File Formats FactsDigital Media File Formats Facts When choosing or using a file format, a When choosing or using a file format, a
number of compromises need to be made number of compromises need to be made such as:such as:
Size of file vs. Quality of fileSize of file vs. Quality of file
Standards based vs. ProprietaryStandards based vs. Proprietary
Cross-platform vs. Sole-platformCross-platform vs. Sole-platform
Delivery method (progressive/streamed vs. all)Delivery method (progressive/streamed vs. all)
Application goals/features (format dictated by Application goals/features (format dictated by application goals)application goals)
Lossless vs. LossyLossless vs. Lossy
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Compromise: File Size vs. QualityCompromise: File Size vs. Quality
BitmapsBitmaps In general, the more quality you want in an In general, the more quality you want in an
image or audio file the larger the file will be.image or audio file the larger the file will be. Compression technologies improve this but Compression technologies improve this but
within a given compression technology, there within a given compression technology, there is usually a quality level for the compression is usually a quality level for the compression and the more you compress to make the file and the more you compress to make the file smaller, the more quality you lose.smaller, the more quality you lose.
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Compromise: File Size vs. QualityCompromise: File Size vs. Quality
Using the appropriate file type and Using the appropriate file type and technologytechnology However, some applications may lend However, some applications may lend
themselves to a particular technology that themselves to a particular technology that excels at providing high quality in a small excels at providing high quality in a small package for that specific type of presentation. package for that specific type of presentation. For example, graphical data that can be For example, graphical data that can be represented by vector objects such as lines, represented by vector objects such as lines, circles, squares, and text can be of much circles, squares, and text can be of much higher quality than bitmap objects as they can higher quality than bitmap objects as they can be presented at any size without loss of be presented at any size without loss of quality (e.g. doesn’t get blocky, or fuzzy).quality (e.g. doesn’t get blocky, or fuzzy).
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Compromise: File Size vs. QualityCompromise: File Size vs. Quality
Examples of CompromisesExamples of Compromises MP3 over WAV – Not exact duplication but MP3 over WAV – Not exact duplication but
sounds the same to most listenerssounds the same to most listeners MIDI for simple music vs. WAV or MP3. MIDI MIDI for simple music vs. WAV or MP3. MIDI
is MUCH smaller but will sound different on is MUCH smaller but will sound different on each target device – however, users will each target device – however, users will recognize the tune (“instruments will sound recognize the tune (“instruments will sound different”).different”).
Vector for Technical/Mechanical Drawings.Vector for Technical/Mechanical Drawings.
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Compromise: Standards vs. ProprietaryCompromise: Standards vs. Proprietary
The amount of data that can be transferred in The amount of data that can be transferred in a given time frame.a given time frame.
Bandwidth AnalogyBandwidth Analogy Low Bandwidth = Single lane dirt roadLow Bandwidth = Single lane dirt road Medium Bandwidth = Two lane paved roadMedium Bandwidth = Two lane paved road High Bandwidth = Multi-lane expressway.High Bandwidth = Multi-lane expressway.
K = Kilo = 1,000K = Kilo = 1,000 M = Mega = 1,000,000M = Mega = 1,000,000 G = Giga = 1,000,000,000G = Giga = 1,000,000,000 b = bitb = bit B = Byte (8 bits in a byte)B = Byte (8 bits in a byte) p = perp = per s = secondss = seconds KB = KiloBytesKB = KiloBytes MB = MegaBytesMB = MegaBytes Kbps = Kilobits per secondKbps = Kilobits per second KBPS = Kilobytes per secondKBPS = Kilobytes per second Mbps = Megabits per secondsMbps = Megabits per seconds MBPS = Megabytes per MBPS = Megabytes per
secondsseconds
Bytes vs. bits per second are Bytes vs. bits per second are frequently represented frequently represented vaguely. You need to vaguely. You need to investigate!investigate!
MeasuringMeasuring Network bandwidth is usually measured in bps (bits Network bandwidth is usually measured in bps (bits
per second) and not BPS (bytes per second).per second) and not BPS (bytes per second). File sizes are usually measured in Bytes and not bitsFile sizes are usually measured in Bytes and not bits Network protocols add overhead to data Network protocols add overhead to data
transmissions. Figure approximately 20%.transmissions. Figure approximately 20%. Shared networks such as Ethernet rarely deliver full Shared networks such as Ethernet rarely deliver full
bandwidth. Figure 40% of total available bandwidth bandwidth. Figure 40% of total available bandwidth for your estimates.for your estimates.
Modems achieve closer to their full rate, but often Modems achieve closer to their full rate, but often have more errors due to line noise. Figure 66% of have more errors due to line noise. Figure 66% of total bandwidth for your estimates. total bandwidth for your estimates.
Picture Size:450 KB
450 KiloBytes450,000 Bytes3,600,000 Bits
Picture Size:450 KB
450 KiloBytes450,000 Bytes3,600,000 Bits
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Graphic Resolutions - 4:3 Ratio RuleGraphic Resolutions - 4:3 Ratio Rule
2048 x 1536
1600 x 1200
1280 x 1024
1152 x 960
1024 x 768
800 x 600
640 x 480
400 x 300320 x 200
64 kpixel
120 kpixel
307 kpixel
480 kpixel
786 kpixel
1.1 Mpixel
1.3 Mpixel
1.9 Mpixel
3.15 Mpixel
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Bit DepthBit DepthNumber of Colors Formula:Number of Colors Formula:
1 bit = 21 bit = 211 = 2 shades (black or white) = 2 shades (black or white)
4 bit = 24 bit = 244 = 64 colors (or shades of gray) = 64 colors (or shades of gray)
8 bit = 28 bit = 288 = 256 colors (or shades of gray) = 256 colors (or shades of gray)
15 bit = 215 bit = 21515 = 32,768 colors = 32,768 colors
16 bit = 216 bit = 21616 = 65,536 colors = 65,536 colors
24 bit = 224 bit = 22424 = 16.8 million colors = 16.8 million colors
30 bit = 230 bit = 23030 = 1 billion colors = 1 billion colors
32 bit = 232 bit = 23232 = 4 billion colors = 4 billion colors
Determining Transfer TimeDetermining Transfer TimeDefinitionsDefinitions
K = Kilo = 2^10 = 1,024K = Kilo = 2^10 = 1,024 M = Mega = 2^20 = 1,048,576M = Mega = 2^20 = 1,048,576 G = Giga = 2^30 = 1,073,741,824G = Giga = 2^30 = 1,073,741,824 b = bitb = bit B = Byte (8 bits in a byte)B = Byte (8 bits in a byte) p = perp = per s = secondss = seconds Kbps = Kilobits per secondKbps = Kilobits per second KBPS = Kilobytes per secondKBPS = Kilobytes per second Mbps = Megabits per secondsMbps = Megabits per seconds MBPS = Megabytes per secondsMBPS = Megabytes per seconds
Bits vs. Bytes per second are Bits vs. Bytes per second are frequently represented vaguely. frequently represented vaguely. You need to investigate!You need to investigate!
MeasuringMeasuring Network bandwidth is usually Network bandwidth is usually
measured in bps (bits per second) measured in bps (bits per second) and not BPS (bytes per second).and not BPS (bytes per second).
File sizes are usually measured in File sizes are usually measured in BPS and not bps.BPS and not bps.
Network protocols add overhead Network protocols add overhead to data transmissions. Figure to data transmissions. Figure approximately 20%.approximately 20%.
Shared networks such as Ethernet Shared networks such as Ethernet rarely deliver full bandwidth. rarely deliver full bandwidth. Figure 40% of total available Figure 40% of total available bandwidth for your estimates.bandwidth for your estimates.
Modems achieve closer to their Modems achieve closer to their full rate, but often have more full rate, but often have more errors due to line noise. Figure errors due to line noise. Figure 66% of total bandwidth for your 66% of total bandwidth for your estimates. estimates.
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Network Bandwidth - Little LeagueNetwork Bandwidth - Little League
0
2,000,000
4,000,000
6,000,000
8,000,000
10,000,000
12,000,000
14,000,000
16,000,000
18,000,000
20,000,000
Bits per Second5
6K
Mo
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WA
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Technology
Little League Bandwidth
Send
Receive
Shared
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Network Bandwidth - Minor LeagueNetwork Bandwidth - Minor League
0
20,000,000
40,000,000
60,000,000
80,000,000
100,000,000
120,000,000
140,000,000
160,000,000
180,000,000
200,000,000
Bits per Second
Ethernet FD WAN T3 Fast Ethernet HD Fast Ethernet FD
Technology
Minor League Bandwidth
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Network Bandwidth - Major LeagueNetwork Bandwidth - Major League
0
1,000,000,000
2,000,000,000
3,000,000,000
4,000,000,000
5,000,000,000
6,000,000,000
Bits per SecondF
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Technology
Major League Bandwidth
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Download Time - Little LeagueDownload Time - Little League
56K ModemWAN Fractional
T1 WAN T1
0.000100.000
200.000300.000
400.000500.000
600.000
700.000
800.000
900.000
1000.000
1100.000
1200.000
1300.000
1400.000
1500.000
1600.000
Se
co
nd
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Technology
Little Leage Download Time
30 secs MPEG @ 360x240 - 30 FPS
1280x960x24 Image (1.8M)
640x480x24 Image (450K)
320x200x8 Image (31.3K)
160x120x8 Image (9.4K)
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Download Time - Minor LeagueDownload Time - Minor League
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FD0.000
10.000
20.000
30.000
40.000
50.000
60.000
Se
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Technology
Minor Leage Download Time
30 secs MPEG @ 360x240 - 30 FPS
1280x960x24 Image (1.8M)
640x480x24 Image (450K)
320x200x8 Image (31.3K)
160x120x8 Image (9.4K)
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Download Time - Major LeagueDownload Time - Major League
Fa
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0.000
0.100
0.200
0.300
0.400
0.500
0.600
0.700
0.800
0.900
1.000
Se
co
nd
s
Technology
Major Leage Download Time
30 secs MPEG @ 360x240 - 30 FPS
1280x960x24 Image (1.8M)
640x480x24 Image (450K)
320x200x8 Image (31.3K)
160x120x8 Image (9.4K)
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Cross Platform vs. Sole PlatformCross Platform vs. Sole Platform
Platform issues are important if you need Platform issues are important if you need to communicate/share data with users on to communicate/share data with users on different platforms and/or operating different platforms and/or operating systems (Macintosh vs. Windows vs. systems (Macintosh vs. Windows vs. Linux). Linux). Use standards based file formats such as Use standards based file formats such as JPG, PNG, MP3, MPG to be sure there JPG, PNG, MP3, MPG to be sure there are viewers/readers on target platforms.are viewers/readers on target platforms.Feel free to use proprietary file formats if Feel free to use proprietary file formats if you control the platform the viewers will be you control the platform the viewers will be using (controlled classroom environment).using (controlled classroom environment).
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Compromise: Progressive vs. StreamedCompromise: Progressive vs. Streamed
All: The entire content is downloaded before any of it All: The entire content is downloaded before any of it is displayed.is displayed.
Progressive/Interlaced: Primarily used for static Progressive/Interlaced: Primarily used for static images. The image is displayed as it is downloaded images. The image is displayed as it is downloaded but the initial quality is much lower than the final but the initial quality is much lower than the final quality once the entire file is transferred. This allows quality once the entire file is transferred. This allows the viewer to get an approximate idea of the image the viewer to get an approximate idea of the image and thus can decide if they want to wait before and thus can decide if they want to wait before proceeding. proceeding.
Streamed: Used most often in video, audio, or Streamed: Used most often in video, audio, or presentations that can be compressed and encoded presentations that can be compressed and encoded such that the data can be displayed as it is being such that the data can be displayed as it is being received. Highly dependant on the bandwidth level received. Highly dependant on the bandwidth level available to the viewer.available to the viewer.
You may need a very specific feature in You may need a very specific feature in your project that will limit your file formats your project that will limit your file formats to a few choices. to a few choices.
For example, you may want to allow the For example, you may want to allow the user to drag and drop an object into your user to drag and drop an object into your image. To do this you would not be able image. To do this you would not be able to use a simple GIF, JPG, or PNG. You to use a simple GIF, JPG, or PNG. You would need to use Flash, special HTML would need to use Flash, special HTML programming, or other higher end, programming, or other higher end, interactive applications and file formats. interactive applications and file formats.
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Digital Media FormatsDigital Media Formats
Compressed – LosslessCompressed – Lossless Refers to data compression techniques in which no Refers to data compression techniques in which no
data is lost. For most types of data, lossless data is lost. For most types of data, lossless compression techniques can reduce the space compression techniques can reduce the space needed by only about 50%. For greater compression, needed by only about 50%. For greater compression, one must use a one must use a lossy compressionlossy compression technique. Note, technique. Note, however, that only certain types of data -- graphics, however, that only certain types of data -- graphics, audio, and video -- can tolerate lossy compression. audio, and video -- can tolerate lossy compression. You must use a lossless compression technique You must use a lossless compression technique when compressing data and programs. when compressing data and programs.
Compressed LossyCompressed Lossy Refers to data compression techniques in Refers to data compression techniques in
which some amount of data is lost. Lossy which some amount of data is lost. Lossy compression technologies attempt to compression technologies attempt to eliminate redundant or unnecessary eliminate redundant or unnecessary information. Most video compression information. Most video compression technologies, such as MPEG, use a lossy technologies, such as MPEG, use a lossy technique. technique.
Streaming MediaStreaming Media Streaming media allows the user to watch or Streaming media allows the user to watch or
listen to a media file without downloading it. listen to a media file without downloading it. The file is simultaneously "streamed" to the The file is simultaneously "streamed" to the user as he or she is watching or listening to it. user as he or she is watching or listening to it. The user needs a player to view or listen to The user needs a player to view or listen to the files - files must be decompressed by a the files - files must be decompressed by a media player that is compatible with the media player that is compatible with the format of the file. format of the file.
Animations - A simulation of movement created Animations - A simulation of movement created by displaying a series of pictures, or frames. by displaying a series of pictures, or frames. Cartoons on television is one example of Cartoons on television is one example of animation. Animation on computers is one of the animation. Animation on computers is one of the chief ingredients of multimedia presentations. chief ingredients of multimedia presentations. Web Animations - World Wide Web - A system Web Animations - World Wide Web - A system of Internet servers that support specially of Internet servers that support specially formatted documents. The documents are formatted documents. The documents are formatted in a script called HTML (formatted in a script called HTML (HyperText HyperText Markup LanguageMarkup Language) that supports links to other ) that supports links to other documents, as well as graphics, audio, and documents, as well as graphics, audio, and video files. video files.
Digital Media FormatsDigital Media FormatsVector GraphicsVector Graphics
Digital pictures that you can easily scale up (such as those in Digital pictures that you can easily scale up (such as those in PostScript, CorelDraw, or CAD formats) are called vector PostScript, CorelDraw, or CAD formats) are called vector graphics. Vector graphics store images in the form of points, graphics. Vector graphics store images in the form of points, lines and shapes, and hence are scalable: they can be resized lines and shapes, and hence are scalable: they can be resized without the loss of image quality. without the loss of image quality.
Vector based files are a set of mathematical and geometric Vector based files are a set of mathematical and geometric descriptions of the objects therein. For example, a curved line, descriptions of the objects therein. For example, a curved line, will have and end and a beginning, a width, a color and a will have and end and a beginning, a width, a color and a description of the amount of curve. This means that the description of the amount of curve. This means that the resolution is not fixed until the file is sent to a printer where it will resolution is not fixed until the file is sent to a printer where it will print at the maximum resolution of the printer. 'Pictures' are far print at the maximum resolution of the printer. 'Pictures' are far too complicated to be described in this fashion. Therefore this too complicated to be described in this fashion. Therefore this type is best suited for 'illustrations' with discreet lines, objects type is best suited for 'illustrations' with discreet lines, objects and areas of color. Fonts fit into this category. Many programs and areas of color. Fonts fit into this category. Many programs combine these two types of information in one file to enable you combine these two types of information in one file to enable you to print 'pictures' with text and 'illustrations'.to print 'pictures' with text and 'illustrations'.
Digital File Formats for Graphics: http://www.2.mrc-lmb.cam.ac.uk/VA/newsite/formats.htmlDigital File Formats for Graphics: http://www.2.mrc-lmb.cam.ac.uk/VA/newsite/formats.html
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Digital Media FormatsDigital Media FormatsVector AnimatedVector Animated Animation - A simulation of movement created by Animation - A simulation of movement created by
displaying a series of pictures, or frames. Cartoons on displaying a series of pictures, or frames. Cartoons on television is one example of animation. Animation on television is one example of animation. Animation on computers is one of the chief ingredients of computers is one of the chief ingredients of multimedia presentations. There are many software multimedia presentations. There are many software applications that enable you to create animations that applications that enable you to create animations that you can display on a computer monitor. Note the you can display on a computer monitor. Note the difference between animation and video. Whereas difference between animation and video. Whereas video takes continuous motion and breaks it up into video takes continuous motion and breaks it up into discrete frames, animation starts with independent discrete frames, animation starts with independent pictures and puts them together to form the illusion of pictures and puts them together to form the illusion of continuous motion. continuous motion.
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Digital Media FormatsDigital Media Formats
BitmapsBitmaps Any picture you see on the Web (or hot off a scanner, Any picture you see on the Web (or hot off a scanner,
or on a page created with a desktop publishing or on a page created with a desktop publishing application) is called a bitmap. As its name suggests, application) is called a bitmap. As its name suggests, a bitmap is a map of dots—similar to what you see a bitmap is a map of dots—similar to what you see when you look at a newspaper photo under a strong when you look at a newspaper photo under a strong magnifying glass—that looks like a picture when magnifying glass—that looks like a picture when viewed from a distance. Bitmaps come in many file viewed from a distance. Bitmaps come in many file formats (GIF, JPEG, TIFF, BMP, PICT, and PCS, to formats (GIF, JPEG, TIFF, BMP, PICT, and PCS, to name a few) and can be read by paint programs and name a few) and can be read by paint programs and image editors such as Adobe Photoshop. If you zoom image editors such as Adobe Photoshop. If you zoom in or try to scale up a bitmap, it will look blocky.in or try to scale up a bitmap, it will look blocky.
HyperlinksHyperlinks Hyperlinks are easy-to-spot underlined words Hyperlinks are easy-to-spot underlined words
or phrases you click in World Wide Web or phrases you click in World Wide Web documents to jump to another screen or page. documents to jump to another screen or page. Hyperlinks contact HTML-coded references Hyperlinks contact HTML-coded references that point to other web pages, which your that point to other web pages, which your browser then jumps to. Hyperlinks are also browser then jumps to. Hyperlinks are also referred to as anchors.referred to as anchors.
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Digital Media FormatsDigital Media FormatsVector StaticVector Static A graphic with no animation or frames. Usually a GIF A graphic with no animation or frames. Usually a GIF
or JPEG file.or JPEG file. Static - Generally refers to elements of the Internet or Static - Generally refers to elements of the Internet or
computer programming that are fixed and not capable computer programming that are fixed and not capable of action or change. The opposite of static is of action or change. The opposite of static is dynamicdynamic. . A Web site that is static can only supply information A Web site that is static can only supply information that is written into the HTML and this information will that is written into the HTML and this information will not change unless the change is written into the not change unless the change is written into the source code. When a Web browser requests the source code. When a Web browser requests the specific static Web page, a server returns the page to specific static Web page, a server returns the page to the browser and the user only gets whatever the browser and the user only gets whatever information is contained in the HTML code. In contrast, information is contained in the HTML code. In contrast, a dynamic Web page contains content that a user can a dynamic Web page contains content that a user can interact with, such as information that is tied to a interact with, such as information that is tied to a database. The user can request that the information, database. The user can request that the information, such as ticket availability or airline flight data, be such as ticket availability or airline flight data, be retrieved from a database. retrieved from a database.
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JPG vs. GIF vs. PNGJPG vs. GIF vs. PNGFollowing are the most commonly used graphics file formats Following are the most commonly used graphics file formats for putting graphics on the World Wide Web and how each for putting graphics on the World Wide Web and how each differs from the others. differs from the others.
JPEG/JPGJPEG/JPGShort for Short for JJoint oint PPhotographic hotographic EExperts Groupxperts Group, the original , the original name of the committee that wrote the standard. JPG is one name of the committee that wrote the standard. JPG is one of the image file formats supported on the Web. JPG is a of the image file formats supported on the Web. JPG is a lossy compressionlossy compression technique that is designed to compress technique that is designed to compress color and grayscale continuous-tone images. The color and grayscale continuous-tone images. The information that is discarded in the compression is information that is discarded in the compression is information that the human eye cannot detect. JPG images information that the human eye cannot detect. JPG images support 16 million colors and are best suited for support 16 million colors and are best suited for photographs and complex graphics. The user typically has photographs and complex graphics. The user typically has to compromise on either the quality of the image or the size to compromise on either the quality of the image or the size of the file. JPG does not work well on line drawings, lettering of the file. JPG does not work well on line drawings, lettering or simple graphics because there is not a lot of the image or simple graphics because there is not a lot of the image that can be thrown out in the lossy process, so the image that can be thrown out in the lossy process, so the image loses clarity and sharpness. loses clarity and sharpness.
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JPG vs. GIF vs. PNGJPG vs. GIF vs. PNGGIFGIFShort for Short for GGraphics raphics IInterchange nterchange FFormatormat, another of the , another of the graphics formats supported by the Web. Unlike JPG, the graphics formats supported by the Web. Unlike JPG, the GIF format is a GIF format is a lossless compressionlossless compression technique and it technique and it supports only 256 colors. GIF is better than JPG for supports only 256 colors. GIF is better than JPG for images with only a few distinct colors, such as line images with only a few distinct colors, such as line drawings, black and white images and small text that is drawings, black and white images and small text that is only a few only a few pixelspixels high. With an animation editor, GIF high. With an animation editor, GIF images can be put together for animated images. GIF images can be put together for animated images. GIF also supports also supports transparencytransparency, where the background color , where the background color can be set to transparent in order to let the color on the can be set to transparent in order to let the color on the underlying Web page to show through. The compression underlying Web page to show through. The compression algorithm used in the GIF format is owned by Unisys, algorithm used in the GIF format is owned by Unisys, and companies that use the algorithm are supposed to and companies that use the algorithm are supposed to license the use from Unisys.license the use from Unisys.**
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JPG vs. GIF vs. PNGJPG vs. GIF vs. PNGPNGPNGShort for Short for PPortable ortable NNetwork etwork GGraphicsraphics, the third graphics , the third graphics standard supported by the Web (though not supported by all standard supported by the Web (though not supported by all browsersbrowsers). PNG was developed as a patent-free answer to ). PNG was developed as a patent-free answer to the GIF format but is also an improvement on the GIF the GIF format but is also an improvement on the GIF technique. An image in a lossless PNG file can be 5%-25% technique. An image in a lossless PNG file can be 5%-25% more compressed than a GIF file of the same image. PNG more compressed than a GIF file of the same image. PNG builds on the idea of transparency in GIF images and allows builds on the idea of transparency in GIF images and allows the control of the degree of transparency, known as the control of the degree of transparency, known as opacityopacity. . Saving, restoring and re-saving a PNG image will not degrade Saving, restoring and re-saving a PNG image will not degrade its quality. PNG does not support animation like GIF does. its quality. PNG does not support animation like GIF does.
**Unisys announced in 1995 that it would require people to pay Unisys announced in 1995 that it would require people to pay licensing fees in order to use GIF. This does not mean that licensing fees in order to use GIF. This does not mean that anyone who creates or uses a GIF image has to pay for it. anyone who creates or uses a GIF image has to pay for it. Authors writing programs that output GIF images are subject Authors writing programs that output GIF images are subject to licensing fees. to licensing fees.
