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One technical problem that arises from running GNUX on a wristwatch is the input. We are experimenting with an input pie menu system, proposed by Callahan, Hopkins, Weiser and Shneiderman, in 1988. They showed that a user can easily select 8 directions of the compass, but since this device has a clockface (at least that is it's concomitant cover usage), a 12 position pie menu makes the most sense, and that is what we are finding works quite well.

The display is typically a computer screen with 480 pixels down and 640 pixels across, measuring approximately 0.7 inches on the diagonal. Upon the display is the image of a clock face, superimposed on top of a video signal from the camera. Time is displayed as a transparent xclock or oclock (or both, one superimposed upon the other). Our modified oclock is available from http://wearcam.org/gclock/ and an exclusive or oclock is under development to reduce screen real estate use.

The device truly looks like an ordinary wristwatch (although one in which the hands are displayed electronically) because it is in fact a wristwatch, among other things. It is natural for such a wristwatch to have a circle displayed on the screen, (this is a feature of the original oclock), but unlike the oclock, to have numbers displayed around the periphery of the circle. In this way it is easier to tell time, and also the numbers may be assigned a secondary meaning (e.g. select ``0'' to stop recording, ``4'' to kill all processes and halt the processor, ``7'' to wake up the system from sleep mode, etc.).

Since humans are quite good at telling time, often the numbers are missing from many commercial wristwatches, and some wristwatches do not even have markings for each hour. Instead, we often rely on our heightened sense of visual acuity to discern the angle of the hands upon the clockface. Thus it is no surprise that the clock menu is usable without paying much attention to the face of the clock. The user just needs to stroke the face of the clock in the direction desired.

The entry of numbers on a touch sensitive clockface in the context of the current invention may be done as vectors (e.g. with no regard to location, only regard to direction). Thus a stroke from left to right is regarded as the number ``3'' regardless of where the stroke begins or ends. A downwards stroke (e.g. from top to bottom) is regarded as the number ``6'' regardless of where the stroke begins or ends, and so on.

Thus telephone numbers can be easily entered into the device, and similarly an alphabet can be constructed much like the alphabet of an automated DTMF answering system used for voicemail and the like in telephony.

Since there are 12 pushbuttons on a telephone, and there are also 12 hours on a clock face, there can be a one to one correspondence between the numbers of the clockface and those of the telephone. The hours 10:00 and 11:00 are used for the symbols ``$*$'' and ``\#'' of the telephone touchpad.

The data entered by way of the clock face menu is typically combined with the video recording made from the scene. The clock face menu is sufficient for entering a department store manager's name, which may be appended to the video file header, so that later a large database of recorded video may be navigated using these short text headers.

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