-Multimedia Basics- Digital Video Integrating Technology into the Curriculum © Jim Lockard 2004

Multimedia Three “technologies“ Three “technologies“  Graphics (images)  Audio  Video

Multimedia Why use: Why use:  Graphics?  Audio?  Video?

Multimedia Applications Applications  Student projects  PowerPoint, CBT, et al  Web  Personal pages  Course support  Course systems  Blackboard

Multimedia File Size How much does it matter? How much does it matter? Impact of delivery method Impact of delivery method  “Local” files  No concern if on hard drive Quickest load timeQuickest load time  Other storage varies CD, Zip, flash drive, networkCD, Zip, flash drive, network  Non-local files  Moving among computers  Download time from web

Graphics Files Size depends on Size depends on  Image size (pixels)  Color depth (1-16M colors)  File format used (jpg, etc) “full screen” x “full color” “full screen” x “full color”  640*480*(24/8) = 921,600 bytes (nominal) 921,600 bytes (nominal)

Graphics Size Example Impact of file type for 640x480 image Impact of file type for 640x480 image Calculated = 921,600 bytes Calculated = 921,600 bytes BMP = 901K BMP = 901K GIF = 219K GIF = 219K  256 color max JPG = 67K JPG = 67K Which format is “best?” Which format is “best?”

Digital Audio Quality Standard = CD Quality Standard = CD CD = 44,100kHz, 16-bit, stereo CD = 44,100kHz, 16-bit, stereo  1 min = ca. 10MB!  172kb/sec FM Radio = 22,050kHz, 8-bit, mono FM Radio = 22,050kHz, 8-bit, mono  1 min = ca. 1.25MB  22kb/sec Telephone = kHz, 8-bit, mono Telephone = kHz, 8-bit, mono  1 min = ca. 625K

File Size & Download Time (Optimum Conditions) Typical song would take nearly 250 sec to download with T1 before playback can begin. 250 sec 250 sec

Digital Video What is it? What is it?  Analog video — digitized  Most common  Original digital video  Newer technology  Catching on very rapidly

Digital Video Benefits Inexpensive computer hardware to create Inexpensive computer hardware to create Non-linear editing w/software Non-linear editing w/software Just another (large) file = transmission potential (sort of) Just another (large) file = transmission potential (sort of)  FTP   web pages More flexible (hyper) use More flexible (hyper) use

To Create Digital Video Hardware Hardware  Analog Digitizing Gear  $50 - $1000+  Digital camcorder + IEEE 1394  Firewire™ or iLink™  Mavica & other digital ‘still’ cameras  PC / web cameras (“golf balls”)

To Create Digital Video Software Software  Comes with hardware & XP  Capture first, then edit  Not always same software  Varies a lot (learning curve)  Match to need, time & skill

Digital Video Issues  Image quality (e.g., jagged lines)  Limited resizing (pixels, jerky)  Differing formats / architectures  Proprietary compression schemes  Broadway AVI, M-JPEG  Storage requirements / download time

Digital Video Files Video = “frames” Video = “frames”  How many / sec? Cf individual graphic image file size Cf individual graphic image file size Video = ++MB Video = ++MB

Digital Video Image Size Size (on screen) Size (on screen)  Pixel dimensions Common Sizes Common Sizes  160 x 120 (1/16)  320 x 240 (1/4)  640 x 480 (‘full’ screen)  720 x 480 (“DVD” wide screen) What the viewer really sees? What the viewer really sees?  Depends on screen resolution

Digital Video Formats QuickTime (mov) QuickTime (mov)  Compatibility issues Video for Windows (avi) Video for Windows (avi)  No further development MPEG (mpg, mpeg, mp#) MPEG (mpg, mpeg, mp#)  MPG1 = general use, Video CD  MPG2 = DVD Streaming Streaming  Real vs MS vs QT  Initial or convert

DV File Size Factors  Image pixel dimensions (size)  FPS – how to choose, if possible?  File format (more later)  AVI to streaming (per software)  Compression scheme (codec)  Within AVI & QT, streaming  Audio sampling (quality)

Impact of File Size 1 min video could take minutes to download

Digital Media How to avoid “downloading”? How to avoid “downloading”?  Can’t truly – files not local  Can avoid complete download Streaming Media Streaming Media  Playback begins quickly  Download to buffer  FIFO  Competing Formats

Original vs Real (low action) 22 sec. AVI (IR32) 1.04MB 5 fps Real (28K) 56K Real (56K) 93K MPEG1 Larger size 3.17MB

Original vs Real (average) 40 sec AVI (Cinepak) 24.6MB Real K Real 56K 176K Real LAN 778K MPEG1 6.18MB

Much detail at  Click on Web Media www3.niu.edu/facdev/media/present ations.htm www3.niu.edu/facdev/media/present ations.htm www3.niu.edu/facdev/media/present ations.htm www3.niu.edu/facdev/media/present ations.htm

Obtaining Video Clip media Clip media Lots on the web Lots on the web But … But …  Much by subscription  Much protected or needs special software, e.g. QuickTime  Some can’t be readily gotten, e.g. streaming Usually need to Right-click to try Usually need to Right-click to try

Creating Digital Video Demo Pinnacle Studio 8 Pinnacle Studio 8  Hardware + Software Microsoft MovieMaker Microsoft MovieMaker  Software only  Windows XP only