DEVICE INCORPORATING IMPROVED TEXT INPUT MECHANISM

• US 20070074131A1
• Filed: 11/16/2006
• Published: 03/29/2007
• Est. Priority Date: 05/18/2005
• Status: Active Grant

• Current Assignee: VL Collective IP, LLC (VideoLabs, Inc.)
• Original Assignee: Nokia Technologies Oy (Nokia Corporation)
• Inventors: Assadollahi, Ramin
• Granted Patent: US 9,606,634 B2
• Time in Patent Office: Days
• US Class Current: 715/816
• CPC Class Codes: G06F 3/0237 using prediction or retrieval techniques
• CPC Class Codes: G06F 40/242 Dictionaries
• CPC Class Codes: G06F 40/274 Converting codes to words; Guess-ahead of partial word inputs

Abstract

A device including a display screen for displaying m-words of data, a text entry device for entering data, a processor receiving data from the text entry device and causing it to be displayed on the display screen. Upon activation the processor initializes a precursor to a predefined value. The device further includes a non-volatile memory storing a dictionary containing a plurality of entries, each entry including an index, a candidate word, and a score. The processor selects a list of n-number of candidate words from the dictionary whose index matches the precursor, and causes m-number of candidate words from the list of candidate words to be displayed on the display screen. The processor causes the display to prompt the user to select one of the displayed candidate words or enter a desired word using the text entry device. Furthermore, a tech-mode for extending a word dictionary for word-based text input is provided.

Claims

1. A device, comprising:

a display screen for displaying m-words of data;

a data entry device for entering data;

a processor receiving data from the data entry device and causing it to be displayed on the display screen, wherein upon activation said processor initializes a precursor to a predefined value;

a non-volatile memory storing a dictionary containing a plurality of entries, each said entry including an index and a candidate word;

said processor selecting a list of n-number of candidate words from said dictionary whose index matches the precursor;

said processor causing m-number of candidate words from said list of candidate words to be displayed on said display screen;

said processor causing the display to prompt the user to select one of the displayed candidate words or enter data for identifying a desired word using said data entry device.

2. The device according to claim 1, wherein in response to the selection of a candidate word, said processor updates the precursor by appending the selected candidate word to the end of the precursor and deleting the leading word, selects a new list of candidate words whose index matches the precursor and causes the display to prompt the user to either select one of the displayed candidate words or enter data for identifying a desired word using said data entry device.

3. The device according to claim 1, wherein said dictionary containing a score associated with at least selected ones of the plurality of entries, said candidate words are displayed on the display screen in an order corresponding to their respective score.

4. The device according to claim 1, wherein said dictionary containing a score associated with at least selected ones of the plurality of entries;

and

wherein if m, the number of words capable of being displayed on the display screen is less than n, the number of candidate words retrieved, then said processor causes m-number of candidate words having the highest score from said list of candidate words to be displayed on said display screen.

5. The device according to claim 1, wherein:

said precursor comprises at least one word; and

if m, the number of words capable of being displayed on the display screen is greater than n, the number of candidate words retrieved, then said processor causes n-number of candidate words from said list of candidate words to be displayed on said display screen, and if said precursor is greater than or equal 2 then the processor deletes the leading word from the precursor, selects a supplemental list of candidate words from said dictionary whose index matches the precursor, and displays m-n number of said supplemental candidate words to be displayed on said display screen.

6. The device according to claim 5, wherein said dictionary containing a score associated with at least selected ones of the plurality of entries;

and

wherein said candidate words are displayed on the display screen in an order corresponding to their respective score.

7. The device according to claim 1, wherein said dictionary containing a score associated with at least selected ones of the plurality of entries, and said processor periodically updates the score of selected said candidate words stored in said non-volatile memory to reflect a frequency of usage.

8. The device according to claim 1, wherein if said processor is unable to find a match between at least one said index stored in said dictionary and said precursor, then said processor creates a new entry in said dictionary in which said precursor is the index and the candidate word is the word entered using said data entry device.

9. The device according to claim 1, wherein the processor causes selected said candidate words from the selected list to be displayed whose initial character(s) match the character(s) entered using said data entry device.

10. The device according to claim 1, wherein said dictionary containing a score associated with at least selected ones of the plurality of entries;

and

wherein said processor causes the display screen to display only candidate words whose score exceeds a threshold value.

11. The device according to claim 1, wherein:

said precursor comprises at least one word; and

if n, the number of candidate words retrieved is a threshold number of words greater than m, the number of words capable of being displayed on the display screen, then said processor increases the size of the precursor by one word, and selects a list of candidate words from said dictionary whose index matches the precursor.

12. A method for inputting text to be displayed on a display screen capable of displaying m-words of data, comprising the steps:

initializing a precursor to a predefined value;

receiving text input data and causing it to be displayed on the display screen;

providing a dictionary containing a plurality of entries, each said entry including an index and a candidate word;

selecting, from the dictionary, a list of n-number of candidate words whose index matches the precursor;

causing m-number of candidate words from said list of candidate words to be displayed on said display screen; and

prompting the user to select one of the displayed candidate words or enter data for identifying a desired word.

13. The method according to claim 12, wherein said dictionary containing a score associated with at least selected ones of the plurality of entries;

and

wherein said candidate words are displayed on the display screen in an order corresponding to their respective score.

14. The method according to claim 12, comprising, in response to the selection of a candidate word, the steps:

updating the precursor by appending the selected candidate word to the end of the precursor and deleting the leading word;

selecting a new list of candidate words whose index matches the precursor; and

prompting the user to either select one of the displayed candidate words or enter data for identifying a desired word.

15. The method according to claim 12, further comprising updating periodically the score of selected said candidate words stored in said dictionary to reflect a frequency of usage.

16. The method according to claim 12, wherein if no match between at least one said index stored in said dictionary and said precursor is found, then a new entry in said dictionary in which said precursor is the index and the candidate word is the entered word is created.

17. The method according to claim 12, wherein selected said candidate words from the selected list whose initial character(s) match the character(s) entered using a text entry device are displayed.

18. Computer program stored on a computer-readable medium for causing a processor to perform the method according to claim 12 when the computer program is executed by the processor.

19. A text input method comprising the steps:

receiving a sequence of key codes, each key code being assigned to a plurality of letters from an alphabet;

determining a suggested sequence of letters from the alphabet corresponding to the sequence of key codes;

displaying the suggested letter sequence and prompting a user to correct a letter of the sequence;

re-determining the suggested sequence of letters corresponding to the sequence of key codes and including the corrected letter; and

repeating the displaying, prompting and determining steps until the user confirms that the displayed letter sequence corresponds to the intended word.

20. Method according to claim 19, wherein, as suggested sequence of letters, the most probable sequence of letters is determined based upon letter transition probabilities.

21. Method according to claim 19, wherein, from the letters assigned to the first key code, the most probable letter to start a word with is determined as first letter in the suggested sequence.

22. Method according to claim 20, wherein the letter transition probabilities include letter bi-grams and/or letter tri-grams.

23. Method according to claim 19, wherein, for each position in the sequence, the most probable letter under consideration of one or more previous letter(s) is determined.

24. Method according to claim 19, wherein the sequence of letters having the overall highest probability of accumulated letter transition probabilities for the entire sequence is determined.

25. Method according to claim 24, wherein the sequence of letters having the overall highest probability is constrained to include corrected letters at their respective positions in the sequence.

26. Method according to claim 19, wherein, when the user moves a cursor to a position in the suggested sequence of letters, a list of alternative letters corresponding to the key code of the selected position is displayed.

27. Method according to claim 26, wherein the user is prompted to select one of the alternative letters for correction of the suggested letter at the cursor position.

28. Method according to claim 26, wherein the list of alternative letters is displayed according to probabilities for the alternative letters at the cursor position, such that alternative letters are selectable with fewer keystrokes or clicks.

29. Method according to claim 28, wherein alternative letters having a higher probability are arranged in display closer to the suggested letter at the cursor position and alternative letters having a lower probability are arranged farther to the suggested letter.

30. Method according to claim 19, wherein the intended word is added to a word dictionary containing a plurality of entries used for dictionary based text input.

41. Computer program stored on a computer-readable medium for causing a processor to perform the method according to claim 19 when the computer program is executed by the processor.

31. A device, comprising:

a display screen for displaying data;

a data entry device for entering data;

a processor receiving data from the data entry device and causing it to be displayed on the display screen;

said processor configured to receive a sequence of key codes, each key code being assigned to a plurality of letters from the alphabet;

said processor configured to determine a suggested sequence of letters corresponding to the sequence of key codes;

said processor configured to cause the display screen to display the suggested letter sequence and to prompt a user to correct a letter of the sequence;

said processor configured to re-determine the suggested sequence of letters based on the corrected letter; and

said processor configured to repeat the displaying, prompting and determination until the user inputs a confirmation signal that the displayed letter sequence corresponds to an intended word.

32. Device according to claim 31, wherein the processor is configured to determine the most probable sequence of letters which meets the conditions of the sequence of key codes and the corrected letters.

33. Device according to claim 31, comprising a statistical letter model representing probabilities for the transition of letters of an alphabet, wherein the processor is configured to select, at each position in the letter string, the most probable letter corresponding to the respective key code and using the letter transition probabilities for determining the suggested sequence of letters.

34. Device according to claim 31, wherein the processor is configured to perform the Viterbi-algorithm for determining the suggested sequence of letters.

35. Device according to claim 31, wherein the data entry device is configured to accept cursor movement control input from the user, and the processor is configured to cause the display screen to position a cursor in the sequence of suggested words in response to the cursor movement control input.

36. Device according to claim 35, wherein the processor is configured to enter a teach mode for adding a new word to the dictionary upon receiving the cursor movement control input.

37. Device according to claim 35, wherein the processor is configured to cause the display screen to display a list of alternative letters assigned to the key code of the suggested letter corresponding to the cursor position.

38. Device according to claim 31, wherein the data entry device is configured to accept letter correction input from the user, the letter correction input indicating one of the other letters assigned to the key code of the corrected letter.

39. Device according to claim 38, wherein the data entry device is configured as a pointing device for indicating a selected letter from a displayed list of alternative letters for a corrected letter.

40. Device according to claim 31, comprising a nonvolatile memory storing a word dictionary containing a plurality of entries, each word entry corresponding to a sequence of letters, said processor configured to add the identified intended word to the dictionary.

42. Portable device, comprising:

a display screen;

a data entry device for entering data;

a processor receiving data from the data entry device, adding it to a text buffer and causing it to be displayed on the display screen,

said processor configured to allow editing of the text in the text buffer based on data received from the data entry device,

wherein the data entry device has a dedicated ‘

WordBack’

key, and

the processor is configured, upon receiving a signal from the data entry device indicating that the ‘

WordBack’

key is activated, to delete the previously received word from the text input buffer and to cause the display screen to display the updated text buffer.

43. Portable device, comprising:

a display screen;

a data entry device for entering data;

a processor receiving data from the data entry device, adding it to a text buffer and causing it to be displayed on the display screen,

said processor configured to allow editing of the text in the text buffer based on data received from the data entry device,

wherein the data entry device has a dedicated ‘

Up'"'"'n'"'"'Blank’

key, and

the processor is configured, upon receiving a signal from the data entry device indicating that the ‘

Up'"'"'n'"'"'Blank’

key is activated, to capitalise the initial letter of the preceding word in the text input buffer and to cause the display screen to display the updated text buffer.

44. Portable device according to claim 43, further comprising predictive text input means for predicting a word following a preceding text input.

45. Portable device according to claim 43, further comprising a word dictionary and means for extending the dictionary by adding a new word.