Intoduction to STB by 08eMGGL

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									Introduction to STB
                       Agenda
What is & why STBs
STB Building blocks
STB Software
– STB RTOS
– Middleware for STB

STB Features & applications
– EPG
– DVR
– CA
                 What is STB ?


STB - Set Top Box
It’s the box that sits on the top of your television
set
                     Why STB ?

Some facts
–   Analog TV sets still
–   Past 20 years has seen the ‘digital boom’
–   TV sets around 10 yrs ago not cable ready
–   STBs not necessarily for digital Tx.
–   STBs has potential to completely replace VCRs
             Why STB (cont…)
Why Digital ?
–   Channel expansion through compression
–   On demand services possible
–   Picture Quality
–   Security and conditional access
–   Data transmission too
–   Flexible Transmission rates (SD vs HD)
                    Why STBs

Expand capabilities of normal Analog TV
Interface the digitized transmission to the still
analog TVs
Easier implementation of CA and customer
management
On demand, PPV and interactive services
                Types of STBs

Analog STBs
– Extended Tuner
– Simple Conditional Access
– Low Cost
               Types of STBs (Cont)

Digital STBs
–   Mpeg2 video
–   Graphics + Video
–   Robust Encryption
–   Interactivity
–   Dual Tuners
–   PVR
–   PIP
–   SD vs HD STBs
                                                                                     PCM            L
            Cable TV Tuner
                                 Video QAM Demod                Descrambler          Audio
                                                     MPEG2 TS                        Engine
Cable I/F
                                                                                            SPDIF
            Cable Modem Tuner    Cable Modem
                                                                Transport
                                                                 Demux            NTSC
                                          MPEG2 TS
                          Mpeg Encoder
                                                                                   PAL
                                                                                  Encoder
                                                                  Video
                                                                 decoder
              Video Decoder
                                                                                       Flash
                                                                Graphics Engine
                                                                 & Compositor
               Memory                          CPU
              Subsystem                                          Bridge               Ethernet


                             USB
                                           Super I/O                  HDD
                        RS 232
               STB H/W (Cont)
Tuner
Demodulator
MPEG Transport Decoder
MPEG Video Decoder
MPEG/Dolby Digital Audio Decoder
Graphic and Video Scalars
CPU , Memory subsystem
Interfaces
MPEG Video and Audio Encoder
       STB Tuners/ Demodulators

Tuner tunes to incoming RF.
QAM demodulation for cable networks
QPSK demodulation for satellite networks
QPSK for cable return channel
             STB Front End



Satellite
                    QPSK    To Demux
            Tuner
                    Demod
          MPEG Transport Decoder

Extraction of PSI information
–   Construct Program Association Table (PAT)
–   Program Map Table (PMT)
–   Conditional Access Table (CAT)
–   Other Tables
Separation of video and audio data
Descrambler for CA
Extraction for other private data
         MPEG Video Decoder

           Video    Graphics         NTSC/PAL
     D    decoder   processor         Encoder
     E
     M
TS   U
           Audio
     X
          decoder
                           CPU




                                 System bus

          Audio
          DAC
                   Graphics

Needed for Displaying User Interfaces
Efficient graphic engine in use of memory and
bandwidth
              CPU subsystem

Runs the STB Applications
MIPS, PPC, ARM
Power consumption
RTOS Availability, S/W development and
debugging tools
           Memory Subsystem

EEPROM – board configuration
FLASH – STB image
Main memory – SDRAM / DDR
               Interfaces

Smart Card
Ethernet
Firewire
USB
Serial Ports
IDE
   MPEG Video and Audio Encoder

Analog PVR realizations
          Video Encoder / Decoder

Encoder
– Converts Pixel info to Analog Composite output
– Support closed caption in the VBI
– Composite, S- Video outputs
Decoder
– Converts PAL/NTSC analog to digital formats
– VBI decoding of CC, teletext
– S-Video and Composite inputs
                 STB Chipsets

LSI Logic
– AViA960x (SPARC based)
Conexant
– CX24155 (ARM based)
ST
– STi551x
Broadcom
– BCM7110, BCM7115 (MIPS based)
Generic STB Software

          End User App


           Middleware



 Porting Interface
                          OS
  H/W Interface
      H/w                BSP
             Hardware Interface

Isolates the functional levels from device and
board configuration
Provides register access for all Endian-ess
                  Porting Interface
APIs for basic chip features at a functional level
Provides a consistent programming interface to
middleware
– Functionalities for Transport/Graphics/MPEG/Audio
  functionalities/FPDM/PVR
Isolates chip level changes from end-user application
development
Facilitates Operating system migration across product
lines
          OS Choices

VxWorks
Linux
Win CE
Nucleus
                        OS

Footprint
Tools
Field upgradability
Processor independence
Support for multitasking etc
Cost , Open source
                  Middleware

Isolates the applications from the OS
Abstract definitions for Threads, Synchronisation
services and memory management
PowerTV, Liberate, Open TV, MHP etc
           STB Applications

EPG
DVR
PIP management
Purchase management
                 References

Workshop on Video Streaming & Digital Cable
Network
Open Cable Architecture – Michael Adams

								
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