Installation guide

• High Eciency AAC v2 (also known as HE-AAC+, eAAC, and aacPlus v2)—A superset of
theAACcorecodecthatcombinesspectralbandreplication(SBR)andparametricstereo(PS)
techniquestoenhancecoding,especiallyforlow-bit-ratestereosignals.HE-AACv2supports
upto48audiochannelsandenables5.1and7.1surroundsound.
FormoreinformationaboutHE-AACimplementation,visitwww.adobe.com/products/hdvideo/
supported_technologies/heaacv2.html.
On2 VP6-S support
Feature in Flash Media Streaming Server and Flash Media Interactive Server; requires Flash Player
9,0,115,0 or later.
Flash Media Server 3.5 features streaming support for the new VP6-S codec prole available
inFlashPlayer9,0,115,0.VP6-Sfeaturesgreatersimplicityinencodinganddecodingof
high-resolution, full-screen video, which allows high-denition video to be streamed and
played back smoothly on mass-market computers with limited processor speeds. VP6-S is
recommendedforvideodeliveredatorabove500Kbpsathighresolutionswhentargeting
these slower machines.
For more information on this codec, visit www.on2.com.
Dynamic Streaming
New feature in Flash Media Streaming Server and Flash Media Interactive Server; requires Flash
Player 10 or later.
Dynamic Streaming is a new quality of service monitoring feature that allows you to detect any
changesinyourviewer’sbandwidthandswitchbetweenstreamsduringplayback—ensuringa
high-quality, uninterrupted stream. Dynamic Streaming uses standard H.264 and VP6 les, and
isActionScript-controlled,usingnewActionScriptmethodsavailableinFlashCS4andFlash
Player10.
For example, if a reduction in client bandwidth is detected, the server can switch to a
standard-denitionstreamatalowerbitrate.Ifnetworkconditionsimprove,theservercan
switch back to HD video. e transitions occur seamlessly in the client. Although network
conditions have changed, the video streaming to the client is uninterrupted.
For the optimal user experience, Dynamic Streaming requires the following:
• edierentversionsorpiecesofcontentmustbesynchronized:thevideotimelinesmustmatch.
• Audioorotherdataineachcontentstreamissynchronizedwiththevideodatainthatstream.
e server transitions between two pieces of recorded content in three possible ways, depending
on the type of content:
• Video-onlystreams—Transitionsoccuratthenearestkeyframeinthetargettimeline.
• Videowithaudiostreams—Transitionsoccurattheaudiosamplethatimmediatelyprecedes
the nearest keyframe in the timeline of the target stream. e audio timelines of the initial and
target streams must match, or an audio artifact results.
• Audio-onlystreams—Transitionsoccuratthenearestpossiblesample.
Implementingtransitionsbetweenlivevideocontentisslightlymorecomplicated.estreams
must have timestamps that are synchronized closely enough, within 3 to 5 milliseconds, so that
the server can select accurate transition points.
Stream transitions occur on the server, but the command to switch streams and the logic to
do so comes from the client application. e application developer includes ActionScript to
monitor download and playback statistics and to switch from the old stream to the new stream
when appropriate.
Adobe recommends that you use Dynamic Streaming for content that meets some or all of the
following criteria:
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