Image Processing Reference
In-Depth Information
Video Phones
The new generation of mobile-phone devices is converging with the role of the handheld
personal digital assistant (PDA). These mobile phones are widely available and have cam-
eras and video playback built in. They also have address books and other PDA-like appli-
cations, although these may be less sophisticated than those found in a genuine PDA.
Some services were being developed for so-called 2.5G mobile phones, but now that the
genuine 3G phones are shipping, they will likely replace the 2.5G offerings.
H.264 on Mobile Devices
H.264 is designed to be useful for mobile devices and consumer playback of video. Rolling
this standard out for some applications must take account of the installed base of players,
and that will take some time. So it is likely that, initially, H.264 will be used primarily as a
mobile format.
The Ultimate Handheld Device
Taking the capabilities of a portable TV, DVD player, PDA, and mobile phone and inte-
grating them into a single device gets very close to the ultimate handheld portable media
device. Well it might, if the capabilities of a sub-notebook computer are included.
A fair use policy is now required for consumer digital video that allows us to trans-
fer our legitimately purchased DVD to a “memory card” or other local-storage medium.
These memory cards are useful gadgets to take on a long journey to occupy us as we
travel, but the content owners are not comfortable with us being able to make such
There are still issues with the form factor for a handheld device like this. To create a
viewing experience that is convenient for long journeys, we might end up with a device
that is a little bulkier than a phone should be. Maybe a hands-free kit addresses that issue
or possibly a Bluetooth headset. Usable keypads increase the size of these devices.
Currently, it is quite expensive to provide sufficient storage capacity without resorting to
an embedded hard disk. That tends to reduce the battery life, so we might look to the new
storage technologies that are being developed. Terabyte memory chips based on holo-
graphic techniques may yield the power-size-weight combination that is required. Newer
display technologies such as organic LED devices may offer brighter images with less
power consumed. Cameras are already reduced to a tiny charged cathode device ( CCD )
assembled on a chip, which is smaller than a cubic centimeter.
The key to this will be standardization. Common screen sizes, players, video codecs,
and connection protocols could enable an entire industry to be built around these devices.
Open standards facilitate this sort of thing, and there are high hopes that H.264 ( AVC ) and
the other parts of the MPEG-4 standard will play an important role here.
3GPP home page:
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