An Introduction to Windows Media Encoder 7.1

Tricia Gill
Microsoft Digital Media Division

May 16, 2001

Summary: This article introduces the new features available in Microsoft Windows Media Encoder 7.1. New features include the addition of the Microsoft Windows Media Audio 8 codec, the Microsoft Windows Media Video 8 codec, and four new profiles that make use of the version 8 codecs for real-time capture and streaming. (6 printed pages)

Download the Windows Media Encoder 7.1 SDK (WMEncoderSDK71.exe) at MSDN Online Downloads.

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Introduction

Microsoft® Windows Media™ Encoder 7.1 has been enhanced to include the latest audio and video compression technologies—the Microsoft Windows Media Audio 8 codec and Microsoft Windows Media Video 8 codec for real-time capture and streaming applications. These codecs, or compressor/decompressors, deliver incomparable audio and video quality at lower bit rates than were possible with previous codec versions.

Windows Media Encoder 7.1 still provides support for all the features that were available in Windows Media Encoder 7, including multiple input sources, on-the-fly source switching for live or on-demand events, and creating and modifying encoding profiles. In addition, the encoder includes four new profiles that were designed specifically for streaming to take advantage of the quality and efficiency of the Windows Media Audio 8 and Windows Media Video 8 codecs.

Windows Media Encoder 7.1 is as easy to use as earlier versions. In fact, the process of setting up an encoding session and encoding your content has not changed. The only change is that your encoded content will look and sound better than before.

This introduction to Windows Media Encoder 7.1 is arranged as follows:

  • Codecs. Describes the new codecs and their compression capabilities.
  • Profiles. Explains the four new encoding profiles that take advantage of Windows Media Audio 8 and Windows Media Video 8 codecs.
  • Things to Remember. Provides recommendations for when you should use Windows Media Encoder 7.1 versus Windows Media 8 Encoding Utility.
  • System Requirements. Lists the system requirements for using Windows Media Encoder 7.1.
  • For More Information. Provides links to additional resources and related articles.

Codecs

Compressor/decompressors, or codecs, are the hardware or software used to compress and decompress audio or video data. For example, Windows Media Audio and Windows Media Video are software codecs used to decrease the bit rate of digital media files so they can be delivered efficiently over a network. Windows Media Encoder 7.1 uses these codecs to compress the data for streaming, while Microsoft Windows Media™ Player decompresses the data for playback.

The Windows Media Audio 8 and Windows Media Video 8 codecs offer excellent compression quality and efficiency. The Windows Media Audio 8 codec delivers a .wma file of the same quality as an .mp3 file, but at nearly one-third the size. The codec is fully compatible with Windows Media Player 7, Windows Media Player 6.4, and all portable devices supporting Windows Media Audio. All of your existing profiles that specified Windows Media Audio 7 will now take advantage of the Windows Media Audio 8 codec, so you can start taking advantage of the improved quality right away. This conversion happens automatically—you don't need to edit any profiles because the Windows Media Audio 8 codec produces content that is bit-stream compatible with previous versions.

While the quality of encoded video depends on the content being encoded, Windows Media Video 8 can deliver near-VHS-quality at bit rates ranging from 250 kilobits per second (Kbps) to 450 Kbps, and near-DVD-quality at 500 Kbps to several megabits per second (Mbps). Windows Media Video 8 codec is appropriate for both streaming and downloading digital media files. It is also compatible with Windows Media Player 6.4 and Windows Media Player 7. Windows Media Video 8 codec can be used with all of your existing encoding profiles and is built into the four new profiles provided in Windows Media Encoder 7.1.

Profiles

A profile is a collection of settings applied to your content during the encoding process in order to achieve your intended result. The profile includes the audio and video codecs used during encoding, plus output video size, audio sampling rate, target bit rate, and other information.

Four new profiles are available in Windows Media Encoder 7.1 that take advantage of the Windows Media Audio 8 and Windows Media Video 8 codecs. These single-bit-rate profiles are intended for real-time capture and streaming of audio and video content; they also support connection speeds ranging from 56 Kbps over a dial-up modem to 500 Kbps over a cable modem or DSL line.

The new profiles are:

  • WM8 Video for DSL/Cable Delivery (250 Kbps, 320 x 240, 30 fps)
  • WM8 Video for DSL/Cable Delivery (500 Kbps, 320 x 240, 30 fps)
  • WM8 Video for LAN Delivery (100 Kbps, 240 x 180, 15 fps)
  • WM8 Video for Modem Delivery (56 Kbps, 160 x 120, 15 fps)

If these profiles do not suit your specific needs, or if you want a multiple-bit-rate profile that uses the version 8 codecs, you can create your own profiles using the Profile Manager feature in Windows Media Encoder. To launch Profile Manager from the main encoder window, point to the Tools menu and click Manage Profiles. Then select an existing profile and click Edit, or click New to walk through the Profile Manager wizard. This wizard allows you to select the Windows Media Audio and Windows Media Video 8 codecs.

When creating custom profiles, remember that the version 8 codecs and Windows Media Encoder 7.1 are best used for real-time capture and streaming of audio and video content. If you intend to convert existing video files (for example, .avi files) to Microsoft Windows Media™ Format, and you want the best quality possible, you should use the Microsoft Windows Media™ 8 Encoding Utility instead. Windows Media 8 Encoding Utility supports two-pass and true variable rate encoding for content that will be downloaded and played locally.

For more information about the Windows Media Encoding Utility, see the Windows Media page of the Microsoft.com Web site. For more information about creating custom profiles with Profile Manager, see Windows Media Encoder Help.

Things to Remember

Windows Media Encoder 7.1 is the best real-time capture tool for audio and video content that you want to stream live or save to a file for on-demand delivery. But additional Windows Media tools are available to meet your encoding needs.

Here are some things to remember when encoding with Windows Media 7.1:

  • Windows Media Encoder 7.1 encodes content at a constant bit rate. This type of encoded content is ideal for streaming. If you are converting high-quality, file-based content and want to preserve the variable bit rate of that content, you should use the Windows Media 8 Encoding Utility. The encoding utility has several modes that let you encode your content in one or two passes, depending on your desired results. However, this type of encoded content is not suitable for streaming because network data rates are constant and cannot accommodate large bit-rate fluctuations.
  • The Windows Media Video 8 codec produces better quality video than the Windows Media Video 7 codec, but its compression computations place higher performance demands on your CPU. If your computer does not have enough power to accommodate encoding with the Windows Media Video 8 codec, you might need to reduce variables such as image size or frame rate, or consider changing your profile to one that uses the Windows Media Video 7 codec.
  • When you use Windows Media Player 7 to play content encoded with the Windows Media Video 8 codec, the Player will automatically download the latest codec. To avoid the automatic download, use Windows Media Player 7.1 or encode your content with the Windows Media Video 7 codec, which is compatible with Windows Media Player 7.
  • The Windows Media Encoder Software Development Kit (SDK) has also been updated with the new codecs. If you are an application developer and want to build custom encoding applications using the version 7.1 SDK, you can download it from the Windows Media page of the Microsoft.com Web site.

System Requirements

The following table provides minimum and recommended configurations for various encoding scenarios: converting files to Windows Media Format, encoding audio-only content, and encoding audio and video content by using the Windows Media 7 and Windows Media 8 codecs.

Encoding task Minimum configuration Recommended configuration
Convert existing .wav, .avi, .mpg, and .mp3 files to Windows Media Format
  • 200 MHz processor, such as an Intel Pentium, with MMX
  • Microsoft® Windows® 98 Second Edition
  • 32 MB of RAM
  • 500 MHz processor or higher, such as a Pentium III
  • Windows 2000
  • 128 MB of RAM or more
Real-time capture and broadcast of audio files
  • 200 MHz processor, such as a Pentium, with MMX
  • Windows 98 Second Edition
  • 32 MB of RAM
  • Supported audio capture device
  • 300 MHz processor or higher, such as a Pentium II or Advanced Micro Devices (AMD) processor
  • Windows 2000
  • 128 MB of RAM or more
  • Supported audio capture device
Real-time capture and broadcast of audio and video files for dial-up modem and mid-bandwidth audiences using the Windows Media 7 codec Single stream and multiple-bit-rate content for 28.8 Kbps and 56 Kbps modems:
  • 300 MHz processor, such as a Pentium II or AMD
  • Windows 98 Second Edition
  • 32 MB of RAM
  • Supported audio and video capture devices
Single stream and multiple-bit-rate content for 100 Kbps through 500 Kbps:
  • 450 MHz processor or higher, such as a Pentium III
  • Windows 2000
  • 256 MB of RAM
  • Supported audio and video capture devices
Real-time capture and broadcast of audio and video files for dial-up modem and mid-bandwidth audiences using the Windows Media 8 codec Single stream content for 28.8 Kbps and 56Kbps modems:
  • 700 MHz processor, such as a Pentium III
  • Windows 98 Second Edition
  • 32 MB of RAM
  • Supported audio and video capture devices
Single stream and multiple-bit-rate content for 100 Kbps through 500 Kbps:
  • 700 MHz dual processor or higher, such as a Pentium III, or a 1.5 GHz, such as a Pentium IV
  • Windows 2000
  • 256 MB of RAM
  • Supported audio and video capture devices
Real-time capture and broadcast of audio and video for high bandwidth (Use recommended configuration) Single stream and multiple-bit-rate content for 500 Kbps through 2 Mbps or more:
  • 700 MHz dual processor or higher, such as a Pentium III
  • Windows 2000
  • 256 MB of RAM or more
  • Supported audio and video capture devices

For More Information

To learn more about Windows Media Encoder 7.1, see Windows Media Encoder Help. Windows Media Encoder 7.1 can be downloaded from the Windows Media page of the Microsoft.com Web site.

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