REAL PLAYER
影音播放系統
什麼是real player
在網上收聽收看實時 Audio、Video 和
Flash 的最佳工具。用 RealPlayer 可欣賞
網上在線音頻和視頻資料。
帶有目標按紐，只需單擊滑鼠就可收聽新
聞和娛樂資訊；近乎CD一樣的音頻效果
全屏播放圖像功能（只適用於高帶寬連接
情況）。
基本功能介紹
可播放50種以上的檔案類型，包括：
Windows Media 、Quicktime 和 DVD
包括進階CD燒錄功能 - 可建立自定 MP3
CD
具有頂級音訊與視訊控制功能 - 圖形等化
器 、淡出淡入 、亮度與對比控制
使用工具列模式可最大化桌面空間
可存取全世界3，000多家廣播電台！
其他功能包括：內容頻道，自動升級功能，
SmartStream 技術消除了再次緩衝，尋
找媒介鏈結，支援 MP3 格式等。
RealVideo 10 Compression
• KEY FEATURES OF REALVIDEO 10
• THE REALVIDEO 10 COMPRESSION
ALGORITHM
• THE REALVIDEO 10 ENCODER
Bitrate
Very often used when speaking of
video or audio quality -- defines how
much physical space one second of
audio or video takes in bits (note:
not in bytes)
KEY FEATURES OF
REALVIDEO 10
Broad reach — Compatible with all
RealVideo 9 decoders
No RealOne™ Player update is needed to
play RealVideo 10 content
Same system, processor requirements for
playback as the previous generation
RealVideo 9
Also plays back in RealPlayer 10
Unparalleled quality — State-ofthe-art video at all bit rates
Same Quality at 30% lower bitrate than
RealVideo 9
Same Quality at 80% lower bitrate than MPEG-2
Same Quality at 75% lower bitrate than HDTV
Same Quality at 45% lower bitrate than MPEG-4
(ASP)
Same Quality at 30% lower bitrate than WMV 9
Same Quality at 15% lower bitrate than H.264
Cross Platform — Available for
playback in multiple environments
Microsoft Windows, Intel Processor (MMXTM, SSETM,
SSE2TM)
Linux, Intel Processor (MMXTM, SSETM, SSE2TM)
Mac OS, PowerPC Processor (AltiVecTM)
WinCE, ARM Processor (ARMv4, StrongARM, XScaleTM)
Symbian, ARM Processor (ARMv4, StrongARM, XScaleTM)
MIPS Processor (NEC vr5500)
Any Device — Extends Internet media across the spectrum
of devices from mobile to TV, PC, HDTV and beyond.
HDTV Ready — supports all HD
formats and resolutions including
720p and 1080i
Interlaced Support — The RealVideo
10 bitstream can carry 60 fields per
second interlaced content
THE REALVIDEO 10
COMPRESSION ALGORITHM
Highly accurate motion modeling
Proprietary spatial pixel prediction
methods
Multi-resolution residual analysis/synthesis
stage
Context adaptive entropy coding
Psycho-visually tuned segmentation and
filtering schemes
Rate-Distortion optimized encoding
algorithms
Two-Pass encoding
The RealVideo 10 Decoder
THE REALVIDEO 10 ENCODER
To accommodate these applications the
RealVideo 10 encoder supports the following
encoding modes:
Constant Bitrate
Variable Bitrate (with a possible maximum
constrained bitrate)
Quality-Based Encoding (with a possible
maximum constrained bitrate)
Real player usage
Education
Enterprise
Government
Service Providers
Resource Library
Education
•
Universities, colleges, local school
districts and other educators are
discovering easy-to-use content
creation, delivery and playback
products and services from Real to
communicate with employees, other
institutions and students.
Case Study
Thomas Telford School has developed
a well-respected online curriculum
employing digital media technology
from Real.
Watch Case Study
Enterprise
Financial services, health care, hightech and other enterprises are
improving communication, increasing
productivity and reducing costs with
Real's complete universal media
delivery system.
Case study
MasterCard International saves over
$10,000 per company meeting using
streaming media technology from
Real. Watch this streaming video
case study to find out how.
Watch Case Study
Government
Federal, state and local government
agencies are training employees, and
communicating with constituents
with Real's scalable and secure
media delivery system.
Resource Library
To help professionals responsible for
streaming media initiatives make
informed decisions, we have
gathered together a library of
resources that includes case studies,
application demos, product literature,
online seminars and more.
Realvideo10
Quality
compare the bitrates required to
achieve the same level of fidelity
using RealVideo 10 and other
popular video formats.
STREAM串流概念介紹
將一連串的影像壓縮後，經過網際網路分
段傳送資料，在網路上即時傳輸影音以供
觀賞的一種技術與過程；串流傳輸可傳送
現場影音或預存於伺服器上的影片，當觀
看者在收看這些影音檔時，影音資料在送
達觀賞者的電腦後立即由特定播放軟體播
放 (如 Windows Media Player, Real
Player,或 QuickTime Player)。
◎串流格式之優缺點比較
優點
即時播放
影片資料不易被複製
不佔硬碟空間
收看者即時隨點隨看
缺點
傳輸品質不佳、畫面失真
為配合數據機或區域網連線的大小，必須壓
縮及放棄多餘的影像資料，造成顆粒狀或
模糊影像及間斷之聲音
Comparison
Fidelity(Peak Signal-to-Noise Ratio,
PSNR)
Bitrate
Encoder Speed
RealVideo 10 provides the same, or better, visual quality using 30%
lower bitrate. (Images from the “Foreman” clip, encoded at 352x288)
Low action
Moderate action
RealVideo 10
Scalability
The Helix™ platform (Producer,
Server and Client) features
RealNetworks’ SureStream™
technology.
Using the Helix Producer, multiple
target bitrates can be selected and
audio and video streams appropriate
for those target bitrates are encoded.
When streamed over a network, the
RealOne™ Player and Helix Universal
Server communicate the appropriate
audio and video streams to be
transmitted.
All of the typical means of scalability
(spatial, temporal and quality) are
utilized in our SureStream
technology.
When selecting multiple target
bitrates for the encoding of a piece of
content, each bitrate selection
represents an independently
decodable stream.
Each of these streams may be
encoded at different resolutions,
frame rates and image fidelities.
And because there are no
dependencies between streams, each
stream can be encoded at a frame
size, frame rate and quality level
optimized for that bitrate.
RealVideo 10 Error
Resiliency
Error resiliency is a major component
of our media delivery platform. Error
resiliency features implemented in
our platform include:
1.The ability to dynamically set FEC
packet insertion rates at nearly every
stage of the delivery network, from
Producer to Server, Server to Server,
Server to Proxies, Proxies to Clients,
etc.
2.Automatic retransmission requests
allow clients to resend data packets
that are lost.
3.The ability to enable error
resiliency modes in our RealVideo
family of codecs.
RealVideo 10 Decoder
Performance
Since RealVideo 10 is designed for
use on a wide variety of clients with
very different performance
capabilities, RealVideo 10 has built-in
CPU scalability in both the encoder
and decoder that allows the faster
processing of video if needed.
CPU USAGE
The encoder/decoder complexity is
asymmetric with the difference in
complexity between the encoder and
decoder near a factor of 3-5 times
under normal (default) encoder and
decoder operation.
1.CIF or QCIF for dial-up
connections – For playback of
typical content for dial-up speeds
(176 x 132), a 200 MHz Pentium II
(or better) is recommended.
CIF是352*288大小的影像
QCIF(176*144)
SIF 大小(240x160 )
2.Full Screen – For playback of 640
x 480 video at full 24 fps (for film) or
30 fps (for video), a 750 MHz
Pentium III (or better) is
recommended.
3.HDTV – For playback of HDresolution content (e.g. 720p), a 2.6
GHz Pentium 4 (or better) is
recommended.
TABLE 1:
RealVideo 10 CPU performance, with zero-wait
memory
Simulation using ADS 1.2 developer tools, with zero-wait memory
Bitrate
Image
Size
Frame
Rate
Contes
t Type
ARM92 XScale
5
30
Kbps
QCIF
15fps
Low
Action
10.8M
Hz
10.7M
Hz
48Kps
QCIF
15fps
Modera 25.4M
te
Hz
Action
25.6M
Hz
250Kp
s
SIF
25fps
High
Action
171.7
MHz
172.9
MHz
200Kp
s
CIF
30fps
Modera 174.9
te
MHz
Action
179.4
MHz
600Kp
s
CIF
30fps
Modera 253.3
te
MHz
Action
257.0
MHz
TABLE 2:
RealVideo 10 decoder CPU usage on XScale™
Machine = ARM XScale, PXA255, iPAQ H5550, 400 MHz
Bitrate
Image
Size
Frame
Rate
Content
Type
CPU
Usage
30 Kbps
QCIF
15 fps
Low
Action
22.9
MHz
48 Kbps
QCIF
15 fps
Moderat
e Action
39.2
MHz
250
Kbps
SIF
25 fps
High
Action
231.3
MHz
200
Kbps
CIF
30 fps
Moderat
e Action
260.4
MHz
600
Kbps
CIF
30 fps
Moderat
e Action
350.2
MHz
TABLE 3:
RealVideo 10 CPU usage on a 1.4 GHz,
Pentium™ 4
Machine = Pentium 4, 1.4 GHz
Bitrate
Image Size
Frame Rate
Content
Type
CPU Usage
48 Kbps
CIF
30 fps
Low Action
81.9 MHz
100 Kbps
CIF
30 fps
Moderate
Action
150.3 MHz
300 Kbps
QVGA
30 fps
Mixed Action 158.3 MHz
800 Kbps
CIF
30 fps
Moderate
Action
260.0 MHz
1.5 Mbps
CIF
30 fps
Moderate
Action
307.9 MHz
MEMORY USAGE
The memory usage of the RealVideo
10 decoder is dependent on the
image size of the video being
decoded. Table 4 presents the
effective memory usage for several
popular resolutions.
TABLE 4: RealVideo 10 memory usage
Image
Size
Code
Size
RAM2
All RAM3
QCIF
172 KB
147 KB
257 KB
CIF
172 KB
315 KB
868 KB
未來展望
Real Player加入Google Bar
RealNetworks宣佈他們將在他們的旗艦產品Real
Player 10，加入Google Bar。在功能上，加入
了搜尋Digital Media的功能，用戶就更加方便。
在合作意義上，當然就RealNetworks這幾年都好
像被微軟力壓，加入Google Bar就是利用Google
這大紅大紫的名稱，希望以Real Player 10重新
上路。
我們可以預期在未來，REAL Player也會
加入MSN的搜尋元素。若可以將MSN的
Search Engine，結合MSN Messenger
的Alert功能，那就更好。比如說，我喜歡
Jon Bon Jovi的話，我可在Windows
Media Player內搜尋他們的歌，以後當在
Media Guide上有這歌手的新歌 / MTV時，
便透過MSN Messenger Alert
RealNetworks的新消息
另外，他們宣佈了一款新的Final Cut
Plugin，名為Real(TM) 10 Export Plugin for Mac OS X，讓Final Cut的用戶可
以直接輸出RealAudio 10或RealVideo
10格式的媒體。
Reference
http://www.realnetworks.com/indust
ries/index.html
http://docs.real.com/docs/rn/rv10/R
V10_Tech_Overview.pdf
RealNetworks RealVedio10 Technical
Overview Version 1.0 Copyright c
2003 RealNetworks, Inc. All rights
reserved.
補充資料
http://toget.pchome.com.tw/intro/networ
k_multimedia/11454.html
http://myurl.com.tw/b9md
http://myurl.com.tw/poci
http://www.azuremedia.net/tech/history/b
rowser/000271.html
http://www.microsoft.com/taiwan/product
s/windows/windowsmedia/tw/compare/
http://www.fg.tp.edu.tw/~betty/vcd.htm
補充資料
http://service.real.com/help/library/e
ncoders.html
https://player.helixcommunity.org/
http://enews.csie.nctu.edu.tw/life/tip
s/tip0006.htm
