2. Disclaimer
The following slides are meant only to
describe high-level interactions. Many
more variables exist in any video
discussion.
Sunday, May 17, 2009
3. Issue at Hand
• Video Performance
• Sometimes slow, choppy - Why?
• Bandwidth
• Video Encoding and Delivery
• Receiving Video
Sunday, May 17, 2009
4. Bandwidth
• Bit rate = data transfer rate and/or
the encoded quality of a video file
• Larger bit rates require more network
and storage use
• Resolution = video display size/quality
• Larger resolutions require more network
and storage use
Sunday, May 17, 2009
5. Video Encoding/Delivery
• Video Encoding
• Different formats, such as Windows
Media or Flash, require different
technologies for delivery
• Delivery from Server
• Streaming = delivers in small chunks
• Download = delivers all at once
Sunday, May 17, 2009
6. End Users
• Players
• Some are plug-ins only, others are plug-
ins calling local applications
• Browser
• Different browsers handle plug-ins and
delivery protocols differently
• Act differently depending on OS
Sunday, May 17, 2009
7. Use Cases
• Common
• Streaming Video - server to client
• Downloading Video - server to client
• Uncommon
• Streaming Video - server to terminal
server to client (terminal services)
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8. Delivery - Server/Client
Streaming Progressive Download
Streaming Server Download Server
vs.
Client Client
connection connection connection connection
begins ends begins ends
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9. Perfect Storm (Part I)
• All variables must match for good end user
experience
• Server technology, client technology,
bandwidth capacity, etc.
• Now, let’s add another layer - Terminal
Server, which acts like a streaming
technology (delivers in small chunks)
Sunday, May 17, 2009
10. Delivery - Terminal
Streaming Progressive Download
Streaming Server Download Server
Terminal Server vs. Terminal Server
Client Client
connection connection connection connection
begins ends begins ends
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11. Perfect Storm (Part II)
• All variables still must match for good end
user experience
• Server technology, client technology,
bandwidth capacity, etc.
• Terminal Server introduces conflicting
technologies for downloaded video, which is
main Charlotte.com delivery
• Download too heavy to transfer seamlessly
Sunday, May 17, 2009
12. Questions?
• Jason Silverstein
Interactive | General and Product Mgmt
jsilverstein@charlotte.com
Sunday, May 17, 2009
15. Video Encoding
• Windows Media
• Microsoft proprietary from client to
server to encoding to delivery
• Live and on-demand are high quality
• Streaming is most prevalent delivery
• Capable of Digital Rights Management
(“DRM”) and HD quality
Sunday, May 17, 2009
16. Video Encoding (con’t)
• Flash Technology
• Format created by Macromedia (now
Adobe), made famous by YouTube
• Encoding more efficient than Microsoft
but relies on third-party video (On2) and
audio (mp3)
• Usually delivered via download
• Lacks HD and DRM capabilities
Sunday, May 17, 2009
17. Video Encoding (con’t)
• QuickTime
• Apple proprietary application
• Uses proprietary and/or standards for
encoding content
• Capable of HD and DRM (both are
industry standards)
• Download is most common delivery
Sunday, May 17, 2009
18. Bit Rate & Resolution
• Part of encoding process
• Bit rate rises as quality increases; dial-up
video = 56 kbps, DSL = 300 kbps, e.g.
• Resolution measures pixels high and wide;
larger numbers create larger file sizes
• Bit Rate and Resolution both affect
playback, especially for downloads
Sunday, May 17, 2009
19. Client Technologies
• Windows Media Player
• Plays Windows Media primarily; can do
some other online formats
• Can play live or on-demand
• Plug-in calls in application from OS,
meaning longer start times
• Tightly integrated into OS through
delivery chain
Sunday, May 17, 2009
20. Client Technologies
(con’t)
• Flash
• Lightweight plug-in
• Plays Flash video only (on purpose)
• Can play live or on-demand
• Considered best “web” experience by
many
Sunday, May 17, 2009
21. Client Technologies
(con’t)
• QuickTime
• QuickTime primarily; other online
formats are possible
• Can play live or on-demand
• Plug-in calls in application from OS,
meaning longer start times
Sunday, May 17, 2009
22. Video Delivery
• Progressive Download (aka “PDL”)
• Using a web server to deliver video in an
on-demand capacity only
• Once request is made, entire file is
delivered at once
• No further requests or communication
with server
Sunday, May 17, 2009
23. Video Delivery (con’t)
• Streaming
• Uses a specialized server and software
to deliver video in small, streamed bits to
the client
• Connection between client and server is
constant through delivery
• Can be used for live or on-demand
Sunday, May 17, 2009