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Plotting the Future of Mobile Digital Video Recorder: A Case Study on Archos and TI

By Guillaume Coffinier, Marketing Manager, Portable Audio and Infotainment
Texas Instruments

It has been nearly five years since the first portable media players hit the market. Coming into the new millennium, many companies turned their focus to begin developing Flash-based digital music players. Archos, however, was several steps ahead of this new market, and instead introduced in 2001 the world's first hard disk drive (HDD)-based Portable Video Recorder (PVR).
In hindsight, it is clear that the enhanced features of the original PVRs were essential to the expansion of the digital audio market. However, back in 2002, when the digital audio market was still gaining mass-market acceptance on its own and consumers had only begun to learn what an “MP3” was, designing a device that was dependent on an HDD and focused on video/imaging was a risky undertaking, considering it was larger and more expensive than audio Flash-based devices. However, Flash modules could contain only a small sampling of a user's available music, and never more than a few image files or brief video clips, if they even had the processing power capabilities to decode them. At 10 GB, the HDD on the first Archos Jukebox could contain thousands of songs and images, as well as complete movies. Early adopters quickly embraced Archos' insight, leading Archos to release a 20 GB device with 3.8” screen and a module to record TV in real time within months.
As the MP3 revolution progressed in the years that followed and TiVo was introduced worldwide, consumers began to understand the true meaning of "any content, anytime" and realize the possibilities that a multifunctional, mass-storage device could enable in both the home and portable markets. Because of its early foresight into the direction the portable market would take and its months (if not years) lead over its competition, Archos, with its fifth-generation of players, continues to drive the portable media player market into new territories. The company's tested recipe for success – proven technology, integration, flexibility, advanced functionality and connectivity – has culminated in the AV700, a Mobile Digital Video Recorder with 100 GB HD capacity and key gaming functionalities in addition to TiVo-like capabilities.

Flexible, Flexible, Flexible

Critical to the success of Archos' portable media players is its flexible underlying architecture. Even though performance is a key requirement, multimedia players need agility to adapt to shifting market demands. While the MP3 standard gave the portable audio market its initial technological boost, a variety of new codecs are emerging, improving playback quality while reducing bandwidth. As the bandwidth requirements for a given quality of video are decreasing, the processing horsepower required to decode this content is increasing. Software powerhouse Microsoft continues to drive digital audio and multimedia with its Windows Media Audio (WMA) and Windows Media® Video (WMV) codecs, while other companies are focusing specifically on the Portable Media Player (PMP) video codec market. Developed in parallel to these codecs are other enhanced services, which promise to further expand and propel the PMP market, such as digital rights management (DRM) which enables secure online distribution of content under new and innovative business models.
To accommodate all of the different codecs and other technology enablers in the growing and changing multimedia content market, Archos required a programmable TV centric platform optimized for video, photos and music mobile applications that would not only provide high-quality recording and playback, but also offer sufficient headroom to implement enhanced product-differentiating functionality. Additionally, to help Archos reach the market first, the platform needed to be power efficient, maximizing playback time, as well as having the right mix of peripherals and memory to simplify overall design, keeps device size down and lower system cost. Finally, Archos wanted silicon that was field-proven and could form the foundation for a robust multimedia platform, leading the company to base its core design around Texas Instruments' Digital Media processor family.
By creating a hardware platform based on TI’s programmable architecture, Archos PVRs are compatible with most multimedia standards. Users are not limited to a single content format, but can natively use almost any digital codec available. TI helped match Archos with the proper codec provider through its vast third party partners. Transparent playback eases the user’s worries about file formats and first having to transcode the file from an unsupported codec to a player-compatible codec. By implementing codecs in software rather than relying on a hard-wired silicon engine, Archos devices have been able to stay current longer than comparable devices. For example, users of the first PMP were able to download software upgrades, enabling them to add new functionality to their player that did not exist when they bought the device.
“Archos is a visionary company that knows the mobile multimedia market and what its customers want,” said Henry Crohas, Chief Executive Officer (CEO) from Archos. “Today, the market is on the edge of a completely new era, far beyond simple audio playback. By selecting a flexible platform, we have been able to harness technology to bring our ideas to reality.”

Modularity and Reuse

While many companies are still working on their first PMP design, Archos has been able to keep its competitive edge through five generations by continuing to reduce its time-to-market and engineering investment with each succeeding generation of devices. Archos actively manages a high level of intellectual property (IP) reuse. Instead of each generation being an entirely new design, Archos has been able to build upon its existing code base and designs. Key to achieving such a high level of reuse has been the choice of a programmable architecture backed by TI’s commitment to facilitating effective reuse in successive generations of Digital Media processors.
Many companies rely upon programming the majority of application code in C to ease portability, but C alone is not enough to ensure reuse across generations. From the very start, Archos worked with TI to carefully plan the architecture, partitioning code in such a way that the various tasks a player must perform are separated into independent segments. Utilizing a dual core ARM + DSP solution allowed Archos to implement a software framework that made the most efficient use of available processing power. The division of labor is done based on core performances for certain tasks, but also on what resources are available at a given time.
This has enabled Archos to quickly and efficiently implement new hardware features without extensive redesign. After all, device performance is improved not solely by increasing clock speeds. Through development of new technologies, such as the latest generation process lithography, additional functionality can be integrated onto devices, both in silicon and from a product or application perspective. Today's system-on-chip (SoC) architectures are optimized for multimedia codecs as a whole, providing efficient performance across the broad range of existing and in the works algorithms. As hardware functions, such as the video encoder, connectivity and memory card interfaces are integrated into the architecture, end product size decreases, while improving ever-important battery life.

For example, when TI introduced new SoC versions of its Digital Media processors with integrated acceleration engines and peripherals, engineers at Archos were able to modify code on a modular basis, only changing code where the updated functions were to be used. In this way, the impact of code changes on the system was kept local, simplifying development and verification. A critical component of this successful migration to higher performance and more integrated devices was the consistent integrated development environment (IDE), TI's Code Composer Studio. The tool chain, testing and verification stays the same as engineers migrate to next-generation silicon, easing porting of code, improving code reusability and reducing overall time-to-market.

Another Archos reuse strategy is to leverage not only their own IP, but off-the-shelf IP for common functionality. This shrinks time-to-market and enables Archos to stay focused on its own value-adding innovations. An added benefit is that third-party software is often carried over to new TI Digital Media processors before silicon is even available for sampling. In many cases, porting such code was as simple as installing an updated library, enabling an early start on application development for Archos.

Moving Forward

With the higher performance available in today's Digital Media processors from TI, Archos has been able to jump forward with enhanced functionality as well, including audio and video encoding and increasingly intuitive and interactive user interfaces, to name a few. For example, with its modular and programmable architecture, Archos was able to be one of the first to market a portable digital video recorder (DVR) device, enabling today's jukebox users to quickly and simply record video from their televisions, without having to go through an unwieldy personal computer.
But market leaders cannot afford to stop innovating. Archos' current industry-shifting move is the PMA400, which offers full portable media player functionality with key PDA applications and WiFi, eliminating the need for users to carry two devices. With the PMA400, Archos continues to reinvent its product lines to drive and expand the portable media player market by penetrating the PDA market.
One of the more important market drivers on the horizon for PMAs is simplified connectivity. Flexible, programmable architectures, coupled with expansive HDDs, have solved content storage and codec compatibility issues. What remains is seamless connectivity of devices to acquire content without effort from users. As USB, WiFi and Bluetooth technology continues to shrink and be integrated with products, backed by robust drivers and a more ubiquitous infrastructure, Archos will be able to create the next-generation of portable media players that download, manage and play digital content in a manner that is as easy to use as it is to listen to and watch.
Archos also envisions leveraging extensive third-party support, allowing the company to increase device functionality without consuming scarce development resources. For example, TI's Digital Media processor supports Mophun, an interface for embedded gaming. Through Mophun, Archos Jukeboxes are able to support a wide range of games without direct significant investment from the company, continually increasing the value of their products over time. TI sees strong growth and market acceptance for future digital audio players that integrate PMP and gaming functionality. Archos’ Gmini 400 series is driving that market as the first devices targeted directly at that segment.
Archos is clearly a key innovator and market leader. With a sharp focus on the needs of consumers, an effective and comprehensive IP reuse strategy, and a modular and programmable platform that enables it to implement and adapt new standards and functionality quickly and easily, it is easy to see why the world turns to Archos for the future of portable multimedia.

Caption: Archos – Then and Now
Figure: to-scale pictures of the 2001 Jukebox MultiMedia player and the 2005 PMA400

Product Jukebox Multimedia PMA400

Storage Capacity

10 GB Hard Drive 30 GB Hard Drive
Video Formats Supported MPEG4 playing (CIF format, 30 f/s, MP3 soundtrack AVI file format) MPEG4 SP with MP3 or ADPCM stereo sound, DVD quality up to 704x480 @ 30 f/s (MTSC), 720x576 @ 25 f/s (PAL), AVI file format
Audio Formats Supported MP3 (30 to 320 kbps - CBR and VBR) Decoding MP3 VBR (30 to 160 kbps) Real-time encoding Stereo MP3 decoding, WMA, WAV, as well as Voice recording with built-in microphone
Imaging Formats Supported BMP, JPEG JPEG, PNG, GIF, BMP
Interfaces USB 1.1 - Optional Interfaces: USB 2.0, FireWire or PC Card High-speed USB 2.0, compatible USB 1.1, PC & Mac USB Host port compatible, Mass Storage Device, Built-in WiFi
Personal Information Management (PIM) Functionalities N/A Qtopia™ software to manage your address book, agenda, calendar, calculator; PDF viewer
Games N/A Qtopia™ embedded games and Mophun™ game engine to play downloadable games
Attachements (separate devices that attach to the player and enable additional functionality) MP3 Recorder, Photo Module, Camera Module, Video Recorder N/A
Dimensions 115 x 83 x 34 mm. (4.5" x 3.2" x 1.3") Approx. 125 x 78 x 20 mm (4.9" x 3.1" x 0.8")
Weight 12.3 oz. 9.9 oz