Choice of compression standards on mobile phones gets wider with VC-1 hardware IP

The IP features the addition of a VC-1 standard compatible decode function to Renesas’ current VPU4 (Video Processing Unit 4) hardware IP enabling encoding and decoding for the MPEG-4 and H.264/MPEG-4 AVC (referred to below as ‘H.264’) video compression standards.
Multimedia content has become well established in the mobile phone field, and video content is in widespread use. Up to now, mobile phone content has centred on MPEG-4 content used in video telephony and the like, while H.264 standard content used by the recently introduced Mobile TV services such as one segment reception, DMB or DVB-H is also becoming increasingly used. Renesas developed the VPU4 enabling MPEG-4 and H.264 encoding and decoding by means of a single hardware IP, and responded to market needs by incorporating this hardware IP in SH-Mobile Series application processors for mobile phone use.
Mobile phone data communication speeds are increasing, together with display data volumes. At the same time, LCD panels with higher pixel counts and resolutions are being used in mobile phones, enabling still larger amounts of data to be displayed.
As a result, mobile phones equipped with a full browsing function have recently been released that allow users to view not only content created for mobile phones but also Web site content created for PCs. However, most content for PCs is created based on the VC-1 standard, and a built-in VC-1 compatible decode function is essential in order to view such content on a mobile phone. With the abundance of VC-1 content, a growing market demand for a built-in VC-1 support function can be expected in the mobile phone field.
Against this background, Renesas has developed an IP with an added VC-1 decode function for its current VPU4 hardware IP.
The added VC-1 support function is a VC-1 standard Simple Profile decode function, enabling 30fps processing for a 720 horizontal pixel x 480 vertical line screen at an IP operating frequency of 66MHz. This enables VC-1 compressed content on a web site to be decoded and played back as smoothly as a normal TV picture.
In adding the VC-1 decode function, processing common to the MPEG-4 and H.264 compression standards shares the same circuitry. Moreover, the VC-1 decoding function shares existing internal memory, minimising the increase in circuit scale.
In addition, special circuit operation techniques have been employed. The clock supply is halted to circuit blocks whose operation is not required for particular content, helping to reduce power consumption. Minimising the increase in circuit scale and supplying a clock only to circuits whose operation is necessary have made it possible to achieve low-power operation.
With three compression standards - MPEG-4, H.264, and VC-1 - supported by this new IP, use of an LSI incorporating this IP allows the development of applications supporting various kinds of content.