Media Center PC Design FundamentalsRequirements And RecommendationsFor Media Center PCs

Hardware PlatformsWindows eHome DivisionMicrosoft Corporation

Agenda

Platform Internals: Great functionality– TV Tuner (Video Capture)

– Compressor

– Decompressor

– Graphics Adapter

– Display Device

– Audio

– Video Quality

Human I/O: Great usability– Remote Control

– Remote Sensor (IR Transceiver)

– Front Panel Display

– Microsoft State Aggregation Service

– Front Panel Controls

The Complete Package: Great look and feel– Form Factor and Industrial Design

– Noise levels

Platform InternalsTV Tuner (Video Capture)

Requirement highlights– Analog Tuners– Implemented as WDM Streaming Capture Device

– Kernel Streaming or AVStream (recommended)

– Audio and video capture on same physical device– A/V noise suppression during channel changes

– Digital Tuners (DVB-T)– Implemented using Broadcast Driver Architecture (BDA)

– Analog/Digital solutions– The user will be prompted to choose analog or digital

during TV setup

Details available in the Windows DDK at Details available in the Windows DDK at http://www.microsoft.com/ddkhttp://www.microsoft.com/ddk

Platform InternalsTV Tuner (Video Capture)

Good analog TV tuner features– Accurate NTSC/PAL decoding

– Correct black levels: Conformance to ITU Rec 601 colorspace

– 3D Y/C separator: Video free of dot crawl, comb filter artifacts

– High signal to noise ratio on video and VBI signals

– Appropriate level of filtering to reduce analog noise without distorting the video’s appearance

– High quality raw VBI data– High sample rate: 1440 samples/second or higher

– Proper gain, waveform, and capture all of lines 1-23

– FM tuner– If implemented, connector must be separate from TV connector

Platform InternalsCompressor

Reduces A/V bandwidth by compressing to MPEG-2 Requirement highlights

– Hardware or software encoder

– Single Main Profile at Main Level MPEG-2 (MP@ML) atfull NTSC/PAL D1 resolution

– Encoder bitrate settings adjusted programmatically using interfaces IEncoderAPI and IVideoEncoderAPI

Good compressor features– Filters video to reduce noise, bit rate without removing detail

– No visible compression artifacts in “Best” mode (6 Mb/s)

– Image quality that compares favorably to standalone consumer electronics PVR devices

Details available in the DirectX SDKDetails available in the DirectX SDKhttp://msdn.microsoft.com/DirectXhttp://msdn.microsoft.com/DirectX

Platform InternalsDecompressor

Decodes MPEG-2 to produce output video frames Requirement highlights

– Compatible with the DirectX VA interfaces by supporting off-host processing of motion compensation and video de-interlacing

– DirectShow property page for audio configuration from inside Windows Media Center

Good decompressor features– Quick MPEG-2 decode (<16ms) to prevent frame drops/glitches– iDCT or VLD MPEG-2 decode acceleration via DirectX VA– Smooth fast forward/rewind and quickly resume to 1x playback– “Media Center Compatible” registry key

– [HKEY_CLASSES_ROOT\CLSID\{083863F1-70DE-11d0-BD4000A0C911CE86}\Instance\{Your Decoder CLSID here}\Capabilities] "{374ac4df-7c98-4257-b13d-36087dbee458}"=dword:00000001

Details available in the DirectX SDKDetails available in the DirectX SDKhttp://msdn.microsoft.com/DirectXhttp://msdn.microsoft.com/DirectX

Platform InternalsGraphics Accelerator

Requirement highlights (minimums)– 4x AGP or equivalent– Graphics Memory: 48 MB– DirectX VA compatible hardware acceleration

– Motion Compensation for MPEG-2 decode assist– Video de-interlacing: BOB

– DXVA_DeinterlaceTech_BOBLineReplicate or DXVA_DeinterlaceTech_BOBVerticalStretch return value from the DXVA_DeinterlaceCaps interface.

– Software-controlled video positioning– If present, TV out circuitry capable of downscaling

a 1024 x 768, 32bpp desktop to NTSC-M/J, PAL, or SECAM

Platform InternalsGraphics Accelerator

Good graphics accelerator features– Analog and digital connectors– Advanced, DirectX VA compatible hardware acceleration and

video de-interlacing– iDCT or VLD– Windows Media Video 9 (WMV9)– High quality, pixel adaptive de-interlacing

– Support for De-Interlace BltEX– New YUV blending mode with lowered video bandwidth

requirements

– Sufficient video memory (128 MB) and bandwidth (10 GB/s) for HDTV decode

– TV out connector assignable to unique display controller– Correct S-Video black level: 0 IRE for RGB (16,16,16)

Platform InternalsGraphics Accelerator

Good graphics accelerator features (continued)– Support for EIA-861B timings for DTV displays and

59.94Hz for NTSC displays

– Screen resolution matched to native display resolution

– No visible artifacts on video scaled to desktop resolution

– Preserved video head and toe room for accurate color reproduction

– “Guaranteed video”: User always sees video– Detect how the user has plugged in video (i.e., VGA or

S-Video) and switch to it

– DDC/CI

– HDCPMeet/exceed high-end Consumer Electronics qualityMeet/exceed high-end Consumer Electronics quality

It’s more than “video just works”It’s more than “video just works”

Platform InternalsDisplay Device

Good display features– Compliance with “Designed for Windows” logo

– High native resolution– At least 1024x768 for 4:3 and 1280x720 for widescreen

aspect ratios

– High brightness, contrast ratio for noise free, pristine video

– No motion blur or trails on moving objects– LCD response time << 16 ms

The user should be able to watch for hoursThe user should be able to watch for hourswithout fatiguewithout fatigue

The user should be able to watch for hoursThe user should be able to watch for hourswithout fatiguewithout fatigue

Platform InternalsDisplay Device

Good display features (continued)– Capable of “natural” color, pre-calibrated for user– 6500K Color temperature

– White point (RGB 235) and black level (RGB 16)set for video

– Easy to adjust, accessible controls forbrightness and contrast

– Proper EDID formatting for Plug and Play support

– DDC/CI support

– DVI input

The user should be able to watch for hoursThe user should be able to watch for hourswithout fatiguewithout fatigue

Platform InternalsAudio

Good audio solution features– Multi-channel output (5.1 and more)– Analog – decode of WMA Pro and DVD audio formats

– S/PDIF – pass through of DVD audio formats

– High quality components laid out properly for clean, noise-free analog output

– “Guaranteed audio”: User always hears audio– Output both analog and digital audio simultaneously

– Or detect how audio is plugged in and switch

– Connectors appropriate to the environment– RCA versus 1/8” in the living room

Platform InternalsA/V Quality

Two key aspects– Stability and reliability: “It feels like a real TV”– Image fidelity: “It looks like a real TV”

Your own eyes are a great way to measure quality– Calibrate the display, no matter what size it is– View video on a large, high quality projection system– Compare video to a known good source

– A consumer electronics device that time-shifts TV– Another PC source

Microsoft is investing in tools to help you evaluate video quality– Windows XP Media Center Edition Partner Test Kit– WHQL DVD Test Annex 2.0 (3.0 coming soon)– Windows XP Media Center Edition 2004 Display Calibration wizard

Always sanity check the system.  If you’re not happy Always sanity check the system.  If you’re not happy with the TV quality, you won’t be the only onewith the TV quality, you won’t be the only one

Human I/OMedia Center Remote Control

Has Windows Media Center required buttons When designing, take in to account

– Consumer Electronics “feel”– Mouse movement is cumbersome and

non-intuitive in a distance interface

– Shape, size, color, weight, balance

– Button location and task-based grouping(transport, navigation, etc.)

– Button number and texture

– Characteristics of the user (i.e., age and gender)

– Windows Media Center recommended and optional buttons

Human I/ORemote Sensor

Includes– IR receiver

– IR emitter– For control of set-top boxes

– Other devices in future

– IR learning circuit– Enables user to add commands for

hardware not yet in the IR database

Capable of bringing machine out of standby Windows Media Center requires implementations based on

one of two designs– Building your own? Contact Microsoft for specifications

– For finished goods – Philips, Mitsumi, SMK

IR Receiver

USB Connection

Connections for IR Emitters

Human I/OFront Panel Display

Beyond “PC status” (power and hard drive)– Can be problematic (constantly flashing HD light?)

Media status is most meaningful to users– TV recording status, channel number, song title,

chapter, and so on

Display can be simple indicator lights, or scale to pixel-addressable displays– Consider a design that can fit in an open drive bay

– great add-on opportunity for traditional form factors

Human I/OMicrosoft State Aggregation Service (MSAS)

Gathers state information from Windows Media Center and provides a stream of state information– Driver-level interface for hardware and/or software– Up to driver/software to interpret this stream into actions

Manages state through “sessions”– A session is created for each media activity and closed when

another activity is started Messages consist of a tag and a value

– Tag describes a state (MSPROPTAG_Mute)– Values modify the tag

– Most are a boolean indication that the state is in effect (MSPROPTAG_Mute = true)

– Some can indicate a state has been turned off (MSPROPTAG_Mute = false)

– Other are integer numeric<volume value> or <channel number>

Human I/OMicrosoft State Aggregation Service (MSAS)

There is no memory in MSAS– States usually become invalid when superseded

by another state– Example: A message setting MSPROPTAG_Pause = true

indicates that the last transport state (such as MSPROPTAG_Play) is now false

– It is up to the driver to maintain this exclusivity– Message setting previous state to false will not be sent

– Multiple messages of the same type and value could be sent consecutively– This behavior is normal and should not cause

problems with a well written driver

Human I/OFront Panel Controls

Provides additional input options on appropriateform factors (i.e., Living Room PC)– Enables the MCPC to appear and behave more like

Consumer Electronics device

– Examples: Transport controls (play, rewind), Navigation (down, left, enter), Volume

Recommendations– Implement driver using Human Interface Device (HID)

– Driver converts input in to the right message

– WM_ INPUT, APPCOMMAND, KEYDOWN, KEYPRESS, KEYUP

– Implement as HID USB device to simplify development

– We don’t recommend doing a user mode solution

– Build to meet the same HID usages as the remote control– Separate buttons (combining increases driver complexity)

– “Play” & “Pause”; “Fast Forward” & “Next”; “Stop” & “Eject”

Commands documented in MSDN whitepaper “Using the Remote Control Device with Windows”

The Complete PackageThe MCPC Look and feel

Fitting into the environment is key– MCPCs are entering “new“ rooms in the home– Consumer Electronics – Great in the Living Room

– All-in-one – Sleek, space saving, flexible

– Small form factors – Versatile in many environments

– Usage scenarios driving form factor changes

– Noise awareness and tolerance varies by room

But Media Center PCs don’t have to be new form factors…

The Complete PackageForm Factor and Industrial Design

Consumers should say “Wow” when they see a Media Center PC, even before they see the software…– Not that it can’t look like a PC, just not like every other PC

Recommendations For all MC PC form factors– Make them unique

– Color, case materials, even color of LEDs

– Integrate essential components– TV tuner, IR transceiver

– Incorporate Windows Media Center specific features– Front panel display, front controls, front inputs

– Minimize or hide traditional “PC” features– Floppy, that BIG power button

– Make them quiet…

Assume MCPCsAssume MCPCswill be displayed prominentlywill be displayed prominently

The Complete PackageNoise Level

Expectations are higher as Media Center PCs enter new rooms and new scenarios

Recommendations– Most obvious: Choose quiet components…

– Fanless components– Fluid bearing drives– Quiet fans for case, CPU, and power supply

– Manage heat differently– Larger fans that turn more slowly– Passive cooling with heat sinks and heat pipes– Case designed for good air flow

– Reduce un-necessary noise– No fan while in standby– Control fan spin-up at system resume– No case rattles– Rubber mount hard drives

Consider the devices MCPCs areConsider the devices MCPCs arecompared against when setting goalscompared against when setting goals