Analog Avenue Column @ www.chipcenter.com
The Arrival of Advanced DVD Players with MPEG-4
by Ken Lowe, VP business development and corporate communications, Sigma Designs, Inc.
This is the first of a three part series. The remaining two parts will take an in-depth look at the hardware and the software designers' perspectives for an advanced DVD player.
The first DVD player most of us purchased was a relatively simple appliance. In rough terms, it was the video equivalent of the audio CD player—insert a disc and play initiates. Over the past two years, many new features have slowly appeared, with each manufacturer attempting to out-merchandize the others. However, with the proliferation of downloadable and consumer-authored content, the next generation of DVD players is being conceived with a higher set of goals. These new players are quickly headed toward a generation of multi-function, higher definition, graphically driven audio/video appliances—in many ways similar to the evolution of today’s surround sound receiver.
Taking On An Expanded Role
When dealing with only pre-recorded content, primarily DVD videos purchased or rented over the counter, the basic concerns tend to be standards and compatibility—will all the DVDs automatically play without error? Occasionally, playing an audio CD presents a small challenge as well, but moving from a single format for audio and video to multiple types of audio, video and still images creates new requirements for the way content is decoded, displayed and played.
Downloaded content is one of the biggest trends in entertainment. The wave of MP3 usage—downloading, burning custom CDs and buying portable players—has created a new paradigm for a huge number of enthusiasts. Starting in the 2001 Christmas selling season, the majority of DVD players sold supported MP3 playback. This holiday season, several new features will emerge.
Windows Media Audio (WMA) provides access to a wide range of published content, and is set to become a pervasive format, based on a new generation of DVD decoder chips now available. There’s also still image viewing, driven by the age of digital cameras and Internet/e-mail exchanges and promoted by such formats as Kodak’s Picture CD. Both of these media types are set to become prolific. Add to this mix the recent introduction of MPEG-4 video content, either downloaded or user created from publicly available CODECs by Apple, DivXNetworks or Sigma Designs. MPEG-4 content is typically captured as an AVI file and stored on a CD in ISO 9660 format, using ISO MPEG-4 video in Simple or Advanced Simple profile and MP3 or Dolby Digital audio.
Navigating through all of the new media presents the latest challenge. The old, automatic plug-n-play approach works for fully standardized, pre-formatted media. However, custom heterogeneous CDs burned with the user’s selection of audio, video and still image files push the need for some form of graphical interface. Fortunately, the television provides a convenient display for the new generation of DVD browsers, which are under development. In the past, the limited user interface functions were handled by small, custom code modules running on very limited microcontrollers. The coming generation of DVD players will break that mold, using a higher powered CPU to execute an HTML coded user interface with vastly expanded graphical capabilities. This will enable consumers to view and play any range of mixed media content selections from their CD or DVD discs, conveniently selected and controlled via their TV.
The Emergence Of MPEG-4 Video
MPEG-4 is the latest-generation digital video compression standard, enabling content developers to create sophisticated programs containing audio, video, text, graphics and interactivity. The object-oriented environment of MPEG-4 provides for complex scene compression at low bit rates or correspondingly small file sizes, making it ideal for either lower cost or higher resolution storage. Based on these advantages, MPEG-4 is beginning to make its way into all forms of set-top appliances, including media gateways, video endpoints, digital cable, satellite, over-the-air systems and now DVD players. Furthermore, through new authoring tools and services, MPEG-4 will enable a new class of interactive video to be utilized for broadcast, on-demand or published media usage.
Utilizing MPEG-4’s compression efficiency for DVD or CD stored media, consumers will be able to enjoy high quality video content, stored in less than half the space currently required. Price-conscious consumers are starting to embrace this advantage and record full-length two-hour movies on low cost CDs. This segment may include downloaded content available through services such as DivXNetworks or user-created content such as the output from Panasonic’s new MPEG-4 Digital Palmcorder® MultiCam™ Camcorders. Likewise, due to the added compression efficiency, the DVD Forum may adopt MPEG-4 as the basis of its new red-laser high-definition DVD-Video (HD DVD-Video)—taking advantage of the increased compression rate to offer higher quality content. For streaming video over the Internet, MPEG-4 is the standard of choice, supported by a plethora of companies and a central element of specifications from the Internet Streaming Media Alliance. Finally, MPEG-4 has almost exclusively become the video compression method for adding video players to mobile phones and appliances.
All of these segments will benefit from future content that employs the rich, object-based interactive capabilities of MPEG-4. The best way to visualize this is to imagine an Internet website in video form. Instead of a fixed graphic background with various objects that are linked to more information, you have live video content in which selected sets of objects are links. These links could lead to more information, close-ups or video vignettes that provide more information about the scene, the actors, the clothing, etc.
The emergence of a trend toward “MPEG-4 Ready” devices is generating increasing demand for fast and easy methods of encoding and producing MPEG-4 compatible files. In support of this trend, Apple, Sigma Designs and others have developed MPEG-4 CODECs to ensure that users can develop content libraries in a manner fully compatible with the MPEG-4 video specifications.
Improving The Visual Experience
All of the aforementioned new media formats will play adequately at DVD resolution on standard analog TV outputs. However, if adequacy were the goal, the technology revolution would have stopped at the VHS generation.
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Figure 1.
Typical output from a standard DVD player (720x480i resolution). The scan lines are obvious when viewed as a large image or up close.
Simply put, progressive scan offers a superior viewing experience for video or graphics content. Already, nearly all new DVD players support progressive DVD output, and by this time next year, should be commensurately offering high definition support as well. Supporting high definition video outputs will also require DVI/HDCP output—the new standard that will appear on nearly all new HDTV sets by the end of year since analog outputs are only supported up to DVD resolution.
Still images, such as those captured as JPEG files using digital cameras or other appliances, typically offer pixel resolutions far above DVD. Even an older 1M pixel digital camera produces an image that exceeds 1280x720 resolution. Displaying electronic photos on high definition TV is the best way to achieve great visual quality in a way that can be enjoyed by a group. Likewise, as interactive content begins to proliferate, the ability to scale the resultant images and video materials will be tightly linked to the quality of the experience.
Most of the DVD decoder chips announced in the last six months support some of the new audio formats, JPEG files and many provide progressive outputs. The most recent example is the EM8500 from Sigma Designs, which supports all the new formats along with several enhanced video quality features. Just announced in June of this year, the EM8500 is a single chip DVD decoder targeted for premium DVD players. As such, it includes support for DVD-Video, Superbit™ DVD, SVCD, VCD, Kodak Picture CD and CD media formats along with playback of DivX™ Video, MP3, WMA and MPEG-4 AVI files on CD. Any of these new video formats can be scaled to resolutions up to 1920x1080i and can be output using progressive or interlaced scan, component or composite output, and analog or DVI outputs. An embedded RISC processor powers a robust on-screen browser, which enables user-selected playback of the any media format stored on disc.
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Figure 2.
1080i output from Sigma Designs' EM8500 (1920x1080i resolution). Scan line structure is now unnoticeable even on large displays and the upscaling is very high quality.
As the role of DVD players continues to expand, advanced formats like MPEG-4 are able to magnify the capabilities of DVD players. This provides consumers with exceptional video quality and increased storage capacity. With these advanced formats and trends developing in the marketplace, the entertainment industry is poised to drive forward to meet consumer demand for technological advancements and deliver multi-function, next generation consumer products to market.
Author’s Bio
Ken Lowe is currently the vice president of business development and corporate communications for Sigma Designs, Inc. His role in this position includes developing strategic partner relationships, directing public and investor relations, directing trade show and special promotions and managing market research.
Lowe has more than 20 years of industry experience in a wide variety of marketing and business management roles primarily focused on multimedia technologies. Lowe joined Sigma in May 2000 as vice president of marketing and was promoted to vice president of business development in January 2001. Immediately prior to joining the Company, Lowe served as the director of multimedia marketing for Cadence Design Systems. Before this, he was vice president of marketing for Chrontel Inc., a consumer semiconductor company focused on TV encoder products. Prior to Chrontel, Lowe was the director of marketing for the multimedia division of Sierra Semiconductor, where he directed the launch of a new line of graphics/video controllers. Prior to this, Lowe was the director and principal analyst of Dataquest’s Microcomponents Service, where he led the market research and analysis for microprocessors, graphics/video controllers and core logic devices. Before joining Dataquest, Lowe founded his own technology company, Performix and also held marketing management positions at WYSE Technology, Personal CAD Systems and Gould-Biomation, as well as an engineering position at Watkins-Johnson.
Lowe holds a BSEE degree from California Polytechnic State University at San Luis Obispo, Calif. |
