With the advent of large-scale wireless communications networks, such as cellular and PCS networks, the distribution of multimedia content over these networks may increase. As used herein, the term “multimedia” content includes analog or digital audio, analog or digital image and/or analog or digital video content.
Mobile wireless communication terminals, such as cellular handsets, wireless RF-equipped personal data assistants (PDAs) and the like, used in a particular network or communication system may have a wide range of functions and/or features. Manufacturers and service providers may provide a wide range of product offerings to customers in order to cater to as broad a segment of the potential market as possible. Thus, for example, some wireless communication terminals used in a network may be capable of downloading and playing high-quality video content, while other wireless communication terminals in the same network may only be capable of downloading and/or playing medium-quality or low-quality video content.
In some cases, wireless communication terminals that may be capable of playing video content of a particular quality may nevertheless be capable of or suited for content having a particular format. For example, a wireless terminal may be configured to display a DVD-quality video stream having a particular aspect ratio, such as 16:9, while another wireless terminal on the same network may be configured to display DVD-quality video in a 4:3 aspect ratio. In particular, a number of standard video formats have been proposed for mobile terminals, including Quarter VGA (QVGA, 320×240 pixels), Common Intermediate Format (CIF, 360×288 pixels) and Quarter Common Intermediate Format (QCIF, 180×144 pixels). Moreover, some mobile terminals may have multiple display screens having different display capabilities. Thus, mobile terminals may be capable of displaying video in one or more of a number of different display formats.
Point-to-point communication of video signals may require an excessive amount of bandwidth, particularly on a wireless network. However, point-to-multipoint transmission (i.e. multicasting) of video content may be an efficient use of the limited bandwidth available to wireless networks. Thus, various protocols for multicasting and broadcasting of video data over wireless networks have been proposed. For example, MBMS (Mobile Broadcast/Multicast Service) and DVB-H (Digital Video Broadcast—Handheld) protocols have been proposed. DVB-H, in particular, is an extension of a digital video broadcast protocol that has been implemented on wired networks in Europe.
USPTO Backgrounds
USPTO Backgrounds