Upcoming Full-HD Trend: - Video processing engine is key to HD video editing and processing
Upcoming Full-HD Trend:
Video processing engine is key to HD video editing and processing
In the consumer electronics field, quality of video images is progressing rapidly (Figure 1 and Figure 2). For example, digital television sets from major manufacturers include products that exceed 40 inches in screen size and most of them increasingly boast full-HD (i.e., 1920 x 1080 resolution) support. Regarding digital video camcorders, recent models are AVCHD-compatible and allow the users to record high-definition video images to an 8cm DVD media or SD memory card. In the next generation DVD arena, HD DVD and Blu-ray Disc are fiercely competing with one another to become the de-fact standard technology while the prices are expected to go down quickly. After all, it is the consumers that will be able to enjoy videos in high-quality, full-HD format.
On the other hand, video usage on the Internet is quickly gaining momentum. The representative example is "YouTube." Video sharing sites such as YouTube have video images that are captured with camcorders or camera phones and often edited or processed (Figure 3). "60 to 70 percent of the video images posted on to YouTube are edited or processed," says a representative of a major video editing software. The quality of the video images uploaded on video sharing sites is thus far as good as QVGA or equivalent. Meanwhile, as the source before processing or editing, videos from full HD compatible equipment are expected for use in the near future. We are certainly heading towards the direction where individual consumers edit and process their full-HD videos on their PCs.
However, we still have a number of issues to comfortably perform editing of such full HD video. One of such issues is that PCs are not powerful enough to edit full-HD video images. For example, "using a desktop PC powered by Core2Duo from Intel, it takes 5 hours, or 100 times of decoding time, to re-encode a 3-minute or so full-HD video in MPEG-4AVC/H.264 codec after editing it," says Mr. Akira Takashima, who is engaged in video editing at HitHops Division of Space Communications Corporation, Tokyo. It is obviously far from a comfortable editing environment.
To solve the issue, we have some alternatives at present. The first alternative is to improve the performance of PC's main processors. Intel Corporation has commercialized "Core2 Quad," a multi-core processor in order to raise the performance. The performance of Core2 Quad is 1.5 times as high as that of Core2 Duo.
The second is to integrate decoder/encoder logic on the GPU for the 3D graphics processing. NVIDIA Corp., a major GPU manufacturer, offers some GPU products that include decoder/encoder logic for MPEG-2 or other codec algorithms. The third is to use a dedicated chip (video processing engine) with decoder/encoder for video processing.
Each alternative has pros and cons. The first and second alternatives tend to cause a problem when the PC runs multiple application programs including video processing. For example, the processor may not utilize 100 percent of its processing capacity for the video processing, causing dropping frames during video playback. Oppositely, other applications may slow down for the sake of video processing. Moreover, the total power consumption of Core2 Quad and the GPU is quite high, up to one hundred and tens of watts; therefore, "it is difficult to consider a pair of high-performance CPU and GPU for a laptop or notebook PC," says a major video editing software developer.
Regarding the third alternative, fabless manufacturers such as Broadcom Corp. develop and offer dedicated codec devices. Also, Toshiba Semiconductor Company is developing a chip called "SpursEngine" that combines SPE (Synergistic Processor Element) used for the Cell Broadband Engine and hardware codec logic for MPEG-4AVC/H.264 and MPEG-2 (Figure 3). The former offers very low power consumption in only some hundreds mW, which is an advantage, but it is difficult to support more than one codec algorithms or a new algorithmic specification. The latter case allows to support more than one codec or new specifications easily because it uses general-purpose ALUs although the power consumption is in the range of 10-watt order.
No matter which method aforementioned becomes the mainstream, it is certain that video processing engines are increasingly necessary and important in the future. As GPUs for 3D processing engine have spread as standard devices for the PC, it is likely for video processing engines to become new standard devices for the PC in the future.
(Nobuyuki Miyazaki, TechnoAssociates)