Large Scale Distribution of Popular Internet “User Generated Content” to
Mobile Devices
J.-M. Bouffard and F. Lefebvre
Presented at the 8th IASTED International Conferences on Wireless and Optical Communications (WOC 2008)
Session 4 – Wireless Components and NetworksTuesday, May 27th 2008
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Agenda
• Introduction– User Generated Content– Broadcast Delivery Vs. Unicast Over Mobile
Networks
• Service Architecture Overview• Trials and Results• Conclusion
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IntroductionInternet technologies that appeared in the wave of Web2.0 have put into place the mechanisms required for every user to become a content creator.
Source: GNUCITIZEN
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Introduction
• This tremendous amount of content is difficult to access in the mobile context.
• New generations of broadcasting networks such as DAB/DMB are currently generating a lot of interest:– High capacity down links– Capabilities to transport
digital data
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Introduction- Broadcast Vs. Unicast -
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Introduction- Goals -
• Produce a technical demonstration showing the combination of:– Mobile broadcast distribution– Participatory web infrastructure
• Rapidly develop a prototype using OSS building blocks whenever possible.
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Service Architecture Overview
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Service Architecture Overview
• 5 Steps:– Content Download.– Metadata extraction.– In-band metadata insertion.– Video and audio equalization.– Playout.
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Service Architecture Overview1. Content Download
• YouTube API– “standard feeds”
top_rated top_favoritesmost_viewed most_discussedmost_linked most_responded
recently_featured watch_on_mobile
Table 1. YouTube API standard feeds
• Youtube-dl
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Service Architecture Overview2. Metadata extraction
• Out-of-band information converted to In-band information.– Video metadata available as XML from the
YouTube API.– XML is parsed with “grep” and regular
expressions.
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Service Architecture Overview3. In-band metadata insertion
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Service Architecture Overview3. In-band metadata insertion
• Clip ranking, title and details.• Transparent channel identification logo
in the corner.• Transparent full screen channel
identification logo overlaid every 15 seconds.
• 10 seconds service identification interlude between clips.
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Service Architecture Overview3. In-band metadata insertion
Original Flash video
Text metatada
Event scripting
Resulting video
Bmovl
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Service Architecture Overview4. Audio / Video equalization
• Video resolution matching.– Mplayer encoder.
• Audio level matching.– Wavegain algorithm.
• Calculates the mean sound level of video.• Outputs a gain value to use on playout.
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Service Architecture Overview5. Playout
• Playout from the PC TV-out port can be inserted into a commercial DMB video encoder.
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Trials and Results
• Test service was transmitted locally with a low power amplifier in the Ottawa area.
• Service was updatedautomatically in real-timeas soon as newvideo were available.
• Commercial receivers weretested for compatibility.
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Trials and Results
Table 2. Tested DMB receivers
Table 3. Informal subjective quality results
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Conclusion
• The concept presented reverses the traditional broadcasting model by letting users produce the content.
• Some challenges need to be addressed:– How to regulate the content?– Can broadcast programming rely on
automated selection based on Internet popularity?
– How to reward content creators/authors?