This chapter is from the book
This chapter is from the book
This chapter is from the book
Wireless Streaming Technologies
As discussed in more detail in Chapter 5, streaming over wireless networks is a challenge, both to achieve good reception between the transmitter and the receiver and to find the proper compression schema to support acceptable quality even when networks have limited bandwidths. Wireless networks, 2.5G and 3G, will support streaming video to mobile phones and hybrid voice-data devices. The emerging MPEG4 standard is promising to become the leading compression codec for the delivery of audio and video to portable voice-data devices. MPEG4 can handle new levels of interactivity. Best of all, it allows content creators to distribute the same piece of streaming video across all sorts of devices, running all sorts of operating systems. Video is the application that promises to ignite the wireless sector. All the hype surrounding 3G wireless service is based on the promise that high-speed data access and streaming applications will deliver a new wireless experience.
MPEG4 is expected to be the promising standard that will deliver video clips to mobile phones, PDAs, and other handheld devices, according to many analysts. This is true for both wireless devices and unconnected PDAs. Some of MPEG4's capabilities, such as the ability to create new content on a stored video image by transferring only a few bits to the device, are revolutionizing the way voice and data will be transmitted on the networks of the future.
Many companies that are developing streaming technologies today are planning ahead to support mobile devices. Their software is designed to play streaming files on cellular phones, handheld PCs, and PDAs. Most of these companies are developing their platforms with plans to use MPEG4 as a compression codec. Microsoft has used MPEG4 codecs since the release of Netshow version 2.0 (the predecessor of Windows Media technology). Windows Media uses an International Standards Organization (ISO)-compliant codec built into the Windows Media codec 7.0 and higher. This allows Windows Media Player to play back content encoded with MPEG4 codecs. RealSystem supports MPEG4 playback as well. Other companies such as PacketVideo have built their entire platforms on MPEG4 from start. The golden age of application development for handheld devices has just started. ActiveSky, Emblaze Research, Philips Digital Networks, RealNetworks, Toshiba, and others are developing systems to stream media to mobile devices. Some use proprietary algorithms that use Java applets to push content; some simply stream their content after it has been encoded with the MPEG4 codec (the traditional server-client relationship used in desktop streaming).
There is a strong relationship between the popularity of streaming media players and the characteristics of the mobile devices hosting them. Streaming media players are software applications residing on top of hardware and firmware equipment. Multimedia presentations require both audio and video functions that are not present in every mobile device. The success of any device relies on its ability to provide rich playback. A good example is the growing popularity of PocketPC devices. This operating system enables live or on-demand playback made possible by a built-in fast CPU, standard large memory bank, and a color display. These hardware functions are not yet present in Palm operating systems or in mobile phones. As a result, although Palm devices are more popular than PocketPC, they still cannot function as a display for multimedia content.
Palm, Inc., has been a pioneer in the field of mobile and wireless Internet solutions and a leading provider of handheld computers, but according to International Data Corporation (IDC) it is losing market share to PDAs running Microsoft's PocketPC and Windows CE operating systems. Based on the Palm OS(R) platform, Palm's handheld solutions allow people to carry and access their most critical information wherever they go. Palm handhelds address the needs of individuals, enterprises, and educational institutions through thousands of application solutions.
Palm is the most popular mobile operating system used by consumers worldwide (according to Palm sources, the operating system reaches over 75% of personal companion devices), but Palm Pilot has always been considered an organizer, not a small computer. In contrast, PocketPC has both the name and the functionality of a big computer, providing a computer-like experience for people on the move. Handspring (the company that introduced enhanced functionality into Palm devices) was the first to reveal a palm device with a color display and additional memory. Until Palm devices offer audio cards and extensive built-in memory, they will fall behind in the race with PocketPC.
When I had finished writing this book, I asked Palm representatives about any plans to release faster processors, a built-in audio card, and additional memory. The reply from Palm's official public relations firm was that Palm does not disclose its plans for future products and has not said anything specific about its future ability to display streaming content. Palm has over 70,000 developers, who are constantly working on new and innovative programs. I guess we will have to wait to see if Palm has plans to compete with PocketPC. Conflicting reports in early 2001 indicated that Palm was moving away from its identity as a handheld-computer maker and toward becoming a provider of backend enterprise systems for supporting all kinds of handhelds—including those of its rivals, PocketPC, Symbian, and Research In Motion. This was the message sent by Palm's acquisition of enterprise-focused Extended Systems, which sells middleware that connects enterprise applications with handheld devices, to make it simple for companies to manage their employees' handhelds just as they do their PCs.
One of the leading companies to introduce media playback on the Palm operating systems is ActiveSky. ActiveSky introduced an interactive media platform designed from the ground up for mobile Palm wireless users. It included authoring tools to encode media files, a server to host and stream content, and a player. The ActiveSky platform enabled additional functionality that displayed rich content through its player. Such content included interactive entertainment channels (furnished by ActiveSky's content partners), real-time data-driven applications (e.g., scores, stocks, and weather), games, multimedia messaging, and profile-based interactive advertising. Since its launch in Australia in 1999, ActiveSky has enjoyed strong sustained growth through its commitment to innovation and quality, intensive research and development, and diligent customer focus, and due to a highly talented team. ActiveSky software is available for an extensive client base across the mobile media industry throughout the world. Among the supported platforms are Windows CE, PocketPC 2002, Palm operating system, Handspring Visor Prism and Platinum, EPOC Psion, and cellular phones. In late 2001, ActiveSky changed its business model and start targeting Telco companies, offering them a server-player solution that would stream not only video or audio, but also rich animation combined with push data. Considering the slow development of 2.5G and 3G networks in North America, such an approach might not be so bad.
Microsoft and PacketVideo offer applications that have been tested and are used today on wireless networks. Other companies may close the gap in the months or years to come, but their products are not yet popular or widely available to the public. To understand how media are streamed to mobile devices, let us discuss the technologies developed by PacketVideo, RealNetworks, and Microsoft that enable content to stream over wireless networks in North America. These technologies can deliver live streaming media in real time (i.e., direct streaming, not downloadable files) to PocketPC devices and selected mobile phones.