Virtual Keyboard Systems with Automatic Correction

Abstract

There is disclosed an enhanced text entry system which uses word-level analysis to correct inaccuracies automatically in user keystroke entries on reduced-size or virtual keyboards. A method and system are defined which determine one or more alternate textual interpretations of each sequence of inputs detected within a designated auto-correcting region. The actual interaction locations for the keystrokes may occur outside the boundaries of the specific keyboard key regions associated with the actual characters of the word interpretations proposed or offered for selection, where the distance from each interaction location to each corresponding intended character may in general increase with the expected frequency of the intended word in the language or in a particular context. Likewise, in a virtual keyboard system, the keys actuated may differ from the keys actually associated with the letters of the word interpretations. Each such sequence corresponds to a complete word, and the user can easily select the intended word from among the generated interpretations. Additionally, when the system cannot identify a sufficient number of likely word interpretation candidates of the same length as the input sequence, candidates are identified whose initial letters correspond to a likely interpretation of the input sequence.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] The present application is a continuation of copending U.S. patent application Ser. No. 10 / 775,483, filed Feb. 9, 2004; which is a continuation-in-part application of U.S. Pat. No. 6,801,190; and claims priority to U.S. Ser. No. 11 / 019,517, filed on Dec. 20, 2004, U.S. Ser. No. 10 / 621,864, filed on Jul. 16, 2003, and to U.S. Provisional Patent Application Ser. No. 60 / 532,131, filed on Dec. 22, 2003 each of which is incorporated herein in its entirety by this reference thereto.TECHNICAL FIELD OF THE INVENTION [0002] The invention relates to systems that auto-correct sloppy text input due to errors or imprecision in interacting with an input device. More specifically, the invention provides automatic correction for keyboards such as those implemented on a virtual keyboard, gesture-based keyboard, and the like, using word-level analysis to resolve inaccuracies, i.e. sloppy text entry. BACKGROUND OF THE INVENTION [0003] For many years, port...

AI Technical Summary

Benefits of technology

[0017] The invention provides an enhanced text entry system that uses word-level disambiguation to correct inaccuracies in user keystroke entries automatically, especially with regard to virtual keyboards.

[0025] a selection component for identifying one or a plurality of candidate objects according to their evaluated ranking, presenting the identified objects to the user, and enabling the user to select one of the presented objects for output to the output device.

[0027] Preferably, (a) each of the plurality of objects in memory is further associated with one or a plurality of predefined groupings of objects; and (b) the word evaluation component, for each generated input sequence, limits the number of objects for which a matching metric is calculated by identifying one or a plurality of candidate groupings of the objects in memory, and for one or a plurality of objects associated with each of the one or a plurality of identified candidate groupings of objects, calculates a matching metric based on the calculated distance values and the frequency of use associated with each candidate object, and ranks the evaluated candidate objects based on the calculated matching metric values. This reduces the calculation required because, conversely, one or more groupings of objects are identified as containing no candidate objects for a given input sequence of interactions such that a matching metric need not be calculated for any object in the groupings so identified.

[0056] a selection component for identifying one or a plurality of candidate objects according to their evaluated ranking, presenting the identified objects to a user, and enabling the user to select one of the presented objects for output to the output device.

[0117] A further embodiment of the invention provides text entry system having: a user input device comprising a virtual keyboard including an auto-correcting region comprising a plurality of keys, each corresponding to a character of an alphabet and each at a known coordinate location, wherein each time a user activates one or a plurality of adjacent keys in the auto-correcting region within a predetermined threshold period of time to generate a key activation event, a determined location corresponding to the key activation event is appended to a current input sequence of the determined locations of the key activation events; a memory containing a plurality of objects, wherein each object is a string of one or a plurality of characters forming a word or a part of a word, wherein each object is further associated with a frequency of use; an output devices and a processor coupled to the user input device, memory, and output device, said processor comprising: a distance value calculation component which, for each generated key activation event location in the input sequence of key activation events, calculates a set of distance values between the key activation event location and the known coordinate locations corresponding to one or a plurality of keys within the auto-correcting region; a word evaluation component which, for each generated input sequence, identifies one or a plurality of candidate objects in memory, and for each of the one or a plurality of identified candidate objects, evaluates each identified candidate object by calculating a matching metric based on the calculated distance values and the frequency of use associated with the object, and ranks the evaluated candidate objects based on the calculated matching metric values; and a selection component for identifying one or a plurality of candidate objects according to their evaluated ranking, presenting the identified objects to the user, and enabling the user to select one of the presented objects for output to the output device.

Problems solved by technology

For many years, portable computers have been getting smaller and smaller.

The principal size-limiting component in the effort to produce a smaller portable computer has been the keyboard.

Miniature keyboards have been used on portable computers, but the miniature keyboard keys have been found to be too small to be easily or quickly manipulated with sufficient accuracy by a user.

Incorporating a full-size keyboard in a portable computer also hinders true portable use of the computer.

A user cannot easily use a portable computer while standing or moving.

Unfortunately, in addition to the fact that printing or writing with a pen is in general slower than typing, the accuracy and speed of the handwriting recognition software has to date been less than satisfactory.

As the size of the keyboard is reduced the user encounters greater difficulty selecting the character of interest.

However, these mechanical keyboards tend to be significantly smaller than the standard sized keyboards associated with typewriters, desktop computers, and even laptop computers.

This increases the likelihood that the user depresses an unintended key, and the likelihood of keystroke errors tends to increase the faster the user attempts to type.

Here again, the small overall size of such keyboards results in a small area being associated with each key so that it becomes quite difficult for the average user to type quickly with sufficient accuracy.

This makes it still difficult to type quickly with sufficient accuracy.

While this approach has merit for such keyboards with a limited number of keys, it is not applicable to reduced size keyboards with a full complement of keys.

Unfortunately, a major obstacle in integrating such virtual keyboards into various data receptive devices is fact that it is very difficult to type accurately when there are no physical keys on which to touch-type.

For all of the preceding systems, the fundamental problem is that the specific activations that result from a users attempts to activate the keys of a keyboard do not always precisely conform to the intentions of the user.

And with a virtual keyboard, the lack of tactile feedback allows the user's fingers to drift away from the desired key registrations.

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