WO2000072301A1

WO2000072301A1 - Method for entering ideographic characters in portable devices

Info

Publication number: WO2000072301A1
Application number: PCT/US2000/012980
Authority: WO
Inventors: Jian-Cheng Huang; Lu Chang
Original assignee: Motorola, Inc.
Priority date: 1999-05-21
Filing date: 2000-05-11
Publication date: 2000-11-30
Also published as: AU4842200A

Abstract

A selective call device (1200) for inputting ideographic characters (300), includes a display (100) for displaying a plurality of soft keys (104, 106, 108) indicative of basic strokes, candidate components, and candidate characters and a processor (1206) for determining most likely candidate characters and candidate components in response to a selected one of a candidate component, or a stroke. The display (100) in response to the processor (1206) displays the most likely candidate components and candidate characters in response to a selected soft key.

Description

METHOD FOR ENTERING IDEOGRAPHIC CHARACTERS IN PORTABLE DEVICES

Field of the Invention

This invention relates in general to portable devices, and more particularly to a method for entering ideographic characters in a portable device.

Background of the Invention

Communication of textual messages between remotely located devices has proliferated greatly in the radio selective call industry. Portable devices, e.g., selective call devices, are widely used to communicate text messages to their users. With the introduction of two-way messaging devices, subscribers can answer or respond with textual messages, as an alternative to voice communications.

Entering and processing information representative of characters in certain languages have become a challenge due to the complexity of certain character sets. For example, ideographic character-based languages, e.g., Chinese characters, include several thousand characters to communicate effectively. This places a burden on the storage and processing capability of a portable device, and requires a large number of keystrokes to entering simple messages.

For example, Chinese text is a stroke based written language that is difficult to input or enter through a regular computing keyboard designed for western languages. A typical keyboard-based Chinese input method relies on some kind of coding scheme, e.g., mapping a key sequence to one or more Chinese characters. This task is difficult because it causes the users to remember numerous unnatural rules or "tricks" and to tolerate a cumbersome procedure for selecting a character from a large character set. Inputting or entering Chinese characters to a portable device is extremely difficult for users of portable devices because the appropriate keyboards are not available in a portable device environment.

Thus what is needed is method for entering or inputting ideographic characters in a portable device that is simple and not burdensome for the users of these devices.

Brief Description of the Drawings

FIG. 1 is a front view of a display illustrating an entry device for entering ideographic characters in accordance with a preferred embodiment of the present invention.

FIG. 2 is a flow diagram illustrating the process for entering ideographic character in accordance with the preferred embodiment of the present invention. FIGs. 3-5 is an example of an ideographic character, the components of the ideographic character, and the basic strokes in accordance with the preferred embodiment of the present invention.

FIGs. 6-10 is an example of the dynamic soft keys showing combinations of basic stroke set, dynamic component set, and dynamic character set in accordance with the preferred embodiment of the present invention.

FIG. 11 is a hierarchical and reverse hierarchical tree diagram showing a dynamic search technique in accordance with the preferred embodiment of the present invention. FIG. 12 is an electrical block diagram of a communication device according to the preferred embodiment of the present invention. Description of a Preferred Embodiment

Referring to FIG. 1, a front view of a display illustrating an entry device for entering ideographic characters in accordance with the preferred embodiment of the present invention is shown. The display 100 preferably comprises a dynamic soft keypad 102 and a display area 110 to facilitate the entry or input of the ideographic characters. It is understood by one skill in the art how to program a computer, a microprocessor, or a digital signal processor to display different graphic environment. Preferably, the dynamic graphic soft keypad 102 comprises, inter alia, three sets of soft keys 104, 106, and 108. Soft keys 104 comprise, e.g., six individual keys corresponding to six basic elements or strokes 104 that make-up the ideographic characters, e.g., the Chinese characters. Soft keys 106 comprise, e.g., six individual keys of the most likely or most common components of the ideographic characters. A component is repeatable or a common element of ideographic characters, e.g., a group or a subset of basic key strokes 104 with fewer key strokes than a completed ideographic character. Soft keys 108 comprise, e.g., six individual keys corresponding to six of the most likely or most common the ideographic characters that could be referred to as candidate characters.

A soft key in the set of a dynamic soft keypad 102 is variable and changes when another soft key in the dynamic soft keypad 102 is pressed. For example, the displayed or assigned functions on each of the key of the basic stroke set 104 does not change because the strokes remain the same for all ideographic characters. However, the functions on soft keys 106, 108 change with each entry or the pressing of soft keys 104, 106, and 108. The basic stroke set 104 are mapped or defined for example as: dot, horizontal stroke, vertical stroke, right-to-left stroke, left-to-right stroke, and cornered strokes. The displayed function of each of the soft key of the dynamic component set 106 is changed or updated in response to a user selecting or pressing one of the key of a basic key stroke 104 (a stroke). Similarly, the displayed function of each of the key of a dynamic character set 108 is changed or updated in response to a user pressing a key of the component set 106 or a stroke 104. When character component soft key 108 is pressed, all soft keys return to their default displayed values.

The displayed six components represents the most common elements or subsets of a candidate character. The number of components is about 800 and is dynamically selected and displayed in response to a user selection or an initial set up. The dynamic character set 108 comprises 6 characters that are dynamically selected from more than 6,000 ideographic characters. For example, using the dynamic soft keys, each soft key graphically displays the shape of a basic stroke 104 or a component 106, or a character 108, and responds to, e.g., a pen touch action, a mouse click, or a user's touch.

Referring to FIG. 2 in conjunction with FIG. 1, and FIGs. 3-10, a flow diagram is used to illustrate the preferred operation of the invention. The component keys 106 and the character keys 108 of FIG. 1 show the default values of the six most frequently occurring or used components 106 and characters 108, respectively. As discussed before, the displayed strokes 104 do not change. Referring to FIG. 2, the process starts at step 200 where the processor, controller, or digital signal processor ("DSP") determines the default values or the most frequent values of the components 106 and the characters 108 to be displayed along with the strokes 104. The default values as presented on the display 100 of FIG. 1. Refer to FIG. 3, the target ideographic character to be entered is the ideographic character 300. To enter or input the ideographic character 300, the user has to view the default values of soft keys to determine if the character is shown on the character keys 108, step 202. When ideographic character 300 is displayed on the character keys 108, the user presses or selects the soft key with the candidate character 300, step 204. This enters or inputs the candidate character 300. On the other hand, when the candidate character 300 is not presented on the character keys 108, step 202, the user then checks the component keys 106 to determined if a candidate component of the character 300 is displayed, step 204.

FIG. 4 shows four candidate components 402, 404, 406, and 408 that are part of the ideographic character 300 and FIG. 5 shows the sequence of strokes 502-524 that form the ideographic character 300 to be entered.

Referring back to FIG. 1, the default values of the soft keys are shown. The candidate character 300 is not shown as one of the default character on the character keys 108 and none of the candidate components 402-408 are shown as a default component on the component keys 106. Operationally, the user simply presses the appropriate soft key sequentially according to the operation flow shown in FIG. 2, until the target or candidate character is displayed on character keys 108. Referring to FIG. 1, the user selects the first stroke 111 (horizontal stroke) as shown in FIG. 1. FIG. 6 displays the next most common or candidate components 106 and candidate characters 108 after the horizontal stroke 111 is selected. A review of the display of FIG. 6, shows that soft key 112 (FIG. 4) is the candidate component 402 of the ideographic character 300. FIG. 4 illustrates all the candidate components 402-408 of the ideographic character 300.

Referring back to FIG. 2, at step 206, the candidate component or element 112 (Fig. 6) of the ideographic character 300 is displayed. The user therefore selects the candidate component 112, step 208. Subsequent to pressing the soft key 112 displaying the desired candidate component, the DSP uses a forward hierarchical /reverse hierarchical tree structure algorithm to calculate or determine the next set of most common characters 108 in response to the user pressing key 112, step 212. A description of the hierarchical /reverse hierarchical tree structure algorithm will be discussed in further details below in reference to FIG. 11. After step 212, the DSP uses the forward hierarchical /reverse hierarchical tree structure algorithm to calculate or determine the next set of most common or candidate components 106, step 214. After the candidate components and characters are determined, the DSP displays the components and characters as shown in FIG. 7. The updated soft keys 102 does not show the ideographic character 300 or any candidate components thereof, therefore the user selects the next stroke 114, step 210. FIG. 5 shows the set, list, or sequence of strokes 502 to 524 that makes up the ideographic character 300.

After the selection of stroke key 114 (FIG. 7), the DSP uses the forward hierarchical /reverse hierarchical tree structure algorithm to calculate or determine the next set of most common characters 108 and components 106, in steps 212, 214 in response to the user selecting key 114. The soft key display 102 is shown in FIG. 8 does not show the ideographic character 300 or any candidate components 404, 406, 408. The user therefore again selects the soft key 116 corresponding to the next stroke of the ideographic character 300. After the pressing of soft key 116, the displayed soft keys are shown in FIG. 9, which again does not include the ideographic character 300 or any of the candidate components 404-408 thereof. The user therefore presses soft key 118 corresponding to the next stroke of the ideographic character 300 as shown in FIG. 5. Subsequent to the user pressing soft key 118, the display updates the soft keys 102 as illustrated in FIG. 10. From FIG. 10, character key 120 shows the target ideographic character 300. When the user enters or presses soft key 120, the desired ideographic character 300 is entered into the portable device.

Accordingly, any target character will eventually be shown in the character soft keys 108. On average, it requires 3-4 touches, presses, selections, or clicks to input or enter a character. In every step, the user's action is in response to the characters and the components that are shown on the updated soft keys 106, 108. The only requirement is that a user has some knowledge of the stroke sequence or element sequence of a character to be entered. This knowledge is a common or rudimentary skill of a normal Chinese; who has received a primary school education. No special training is therefore needed for using the proposed scheme. Referring to FIG. 11, a hierarchical 1100 and reverse hierarchical tree 1110 structure type search routines are shown for selecting ideographic characters and elements, parts, or components of the ideographic characters based on inputs. To facilitate an efficient search, two hierarchy tree structures are constructed for all the characters and their stroke sequences. These two hierarchy trees organize stroke sequences in opposite ways. A top-down or forward hierarchy tree 1100 starts with the first keystroke 104. With each subsequent stroke, the search branches or follows the hierarchical tree down the respective path, e.g., to nodes 10, 12, 14, 16 as is well known for hierarchical search routines. As long as the user continues to enter or input strokes, the search algorithm continues down the top down (or forward) tree 1100 with each subsequent stroke until it reaches the end. The bottom-up (backward) hierarchy tree 1110 starts with the last stroke and works backward on a path through nodes 10, 12, 14, and 16 to the first strokes. In such a data structure, a component spans a successive number of branches. Generally when both the top-down hierarchy tree 1100 and the bottom-up hierarchy tree 1110 converge, the list of updated characters and components are found or the desired ideographic character is found 1102. Specifically, the method of searching for a candidate character traverses the tree from top to bottom following the stroke sequence. When components are specified, search can be done more efficiently. Components can be located in the tree. All descendents of the components form the pool of candidate characters, from which top choices will be displayed. Since this pool of candidates can be fairly large, the bottom-up hierarchy tree is searched using the specified component generates a separate pool of candidate characters. Only those candidates common to both pools are used to generate the ranked list of candidate characters and components to be displayed. Thus, the candidate pool is reduced. When new strokes or components are presented, only the pool of candidates needs to be searched. Referring to FIG. 12, a selective call device 1200 according to the preferred embodiment of the present invention comprises an antenna 1202 that provides an RF carrier signal to a receiver 1204. The receiver 1204 generates a recovered signal suitable for processing by a digital signal processor ("DSP") 1206 in a manner well known to one of ordinary skill in the art. The DSP 1206 performs function such as encoding and decoding messages and controlling the operation of the selective call device 1200 well known to one of ordinary skill in the art. The DSP 1206 processes the received signal to decode the address and compares the decoded address with one or more predetermined addresses contained in a memory, for example, a code plug 1218. When the addresses are same or substantially similar, the user is alerted that a signal has been received either by an audio alert (e.g., a speaker or transducer) 1212 or a tactile alert (e.g., a vibrator) 1214. The received signal may also include optional message data directed to some selective call device 1200. Also, if the selective call device 1200 includes an optional voice output, recovered audio components of the received RF signal may be presented. For a message selective call device 1200, the recovered message is stored in a memory 1208 for subsequent presentation by an output device which for example is a display 100. The display 100 according to the present invention is described in reference to FIG. 1 and includes a plurality of soft keys 104, 106, 108; the function being assigned thereto depends on user entry. The output devices will automatically, or when manually selected with switches 1216, present the message, such as by displaying the message in the display area 110 of the display 100. A power switch 1210 performs battery saving function as is well known in the art. For an acknowledge-back selective call receiver 1200 (or two-way selective call device), a signal is transmitted either automatically or manually from the selective call device 1200 in response to the receipt of a selective call message (or signal). The user, in the case of a manual response, uses the switches 1216 or soft keys 104, 106, and 108 to select or compose a message to be sent to the originator. The message is then encoded by the DSP 1206 and passed to a transmitter 1120 for transmission by the antenna 1202. Although the preferred embodiment of the present invention describes a selective call device, it can be appreciated the other portable device, e.g., portable devices that include dictionaries, thesaurus, or any of the numerous devices that can accepts user entered text for storing, transmitting or processing, etc., are within the scope of the present invention. In this way, any target ideographic character will eventually be found and displayed on the character soft keys 108. On average, it requires 3-4 touches, presses, selections, or clicks to input or enter a desired ideographic character. In every step, a user's action is in response to the characters and the components that are shown on the updated soft keys 106, 108. The only requirement is that a user has some knowledge of the stroke sequence or element sequence of a character to be entered. This knowledge is a common or rudimentary skill of a normal Chinese; e.g., who received a primary school education. No special training is needed for using the proposed scheme.

In summary, a method for inputting ideographic characters comprising the steps of (a) displaying basic strokes, candidate components, and candidate characters, (b) determining the most likely candidate characters and candidate components in response to a selected one of a candidate component, or a stroke, (c) displaying the most likely candidate components and candidate characters in response to the selected candidate component or stroke. The step of displaying displays the strokes and the candidate characters on or as a plurality of soft keys. The method includes the step of selecting a candidate character, a candidate component, or a stroke in an order of preference beginning with the candidate character if displayed, or the candidate component if displayed or the stroke. The method of selecting comprises first selecting a candidate character, second selecting a candidate component when the candidate character is not present, and third selecting a stroke when the candidate character and the candidate component are not present. The step of selecting includes: pressing a soft key corresponding to a desired displayed candidate character; or pressing a soft key corresponding to a component when the desired candidate character is not displayed. The step of determining includes searching for the most likely candidate components and candidate characters using a top-down or forward hierarchy tree and a bottom-up or backward hierarchy tree search. It is appreciated that the functionality of a selective call device can be integrated into higher level devices, such as computers, portable data assistances, cellular telephones, etc. The above description is intended by way of example only, and is not intended to limit the present invention in any way, except as set forth in the following claims. What is claimed is:

Claims

CLAIMS 1. A method for inputting ideographic characters in a portable device, comprising the steps of:

(a) displaying strokes and candidate characters; (b) determining most likely candidate characters in response to a selected stroke;

(c) displaying the most likely candidate characters; and

(d) repeating steps (b) and (c) until a candidate character is selected.

2. The method according to claim 1 further comprising the steps of: displaying candidate components; and determining the most likely candidate components and candidate characters in response to a selected one of a candidate component or a stroke.

3. The method according to claim 1 further comprising a step of: first selecting a candidate character, and second selecting a stroke when the candidate character is not present.

4. The method according to claim 3 where in the step of selecting further comprising the step of: pressing a soft key corresponding to a desired candidate character; and pressing a soft key corresponding to a stroke when the desired candidate character is not displayed.

5. The method according to claim 1 wherein the step of determining further comprises the step of searching for most likely candidate components and candidate characters using a hierarchical tree algorithm.

6. The method according to claim 1 further comprises the step of selecting a stroke or a candidate character in an order of preference beginning with the candidate character if displayed or a stroke.

7. A selective call device for inputting ideographic characters, comprising: a display for displaying a plurality of soft keys indicative of basic strokes, candidate components, and candidate characters; a processor for determining most likely candidate characters and candidate components in response to a selected one of a candidate component, or a stroke; and wherein the display, in response to the processor, displays the most likely candidate components and candidate characters in response to a selected soft key.

8. The selective call device according to claim 7 wherein the display displays the candidate characters and the candidate components on a plurality of soft keys that are assignable in response to a selected soft key.

9. The selective call device according to claim 7 wherein the processor further comprises a hierarchical tree search routine for most likely candidate components and candidate characters in response to a selected soft key.

10. The selective call device according to claim 9 wherein the hierarchical tree search routine comprises a hierarchical tree top-down search method and a hierarchy tree bottom-up search method.