Method for storing and comparing computer generated lines

• US 7,663,614 B2
• Filed: 10/05/2004
• Issued: 02/16/2010
• Est. Priority Date: 10/05/2004
• Status: Active Grant

• Current Assignee: Jclads Corporation
• Original Assignee: Jeff Maynard
• Inventors: Pham, Nghia Van
• Primary Examiner(s): DHARIA, PRABODH M
• Application Number:
  US10/957,581
• Publication Number:
  US 20060071906A1
• Time in Patent Office: 1,960 Days
• Field of Search: 345/166, 345/173, 345/158, 345/163, 345/156, 345/179, 345/443, 345/204, 345/87, 345/694, 345/72, 345/88, 345/630, 345/589, 345/903, 345/467, 345/468, 351/246, 715/763, 710/72, 700/98, 358/463, 358/3.23, 702/150
• US Class Current: 345/204
• CPC Class Codes: G06F 2218/12 Classification; Matching
• CPC Class Codes: G06F 40/194 Calculation of difference between files
• CPC Class Codes: G06V 30/1423 the instrument generating sequences of position coordinates corresponding to handwriting preprocessing or recognising digital ink G06V30/32
• CPC Class Codes: G06V 40/394 Matching; Classification

Abstract

A method is provided for creating a quadrant array by using two consecutive points in an array of x, y coordinate values generated by movements of a computer mouse or a digitizer tablet. The quadrant array is then saved in computer storage for later verification with a sample quadrant array by using a comparison function.

Claims

1. A method for creating an array of quadrants using a computer, the computer

comprising a processor, a memory, and either a computer mouse or a digitizer tablet, the method comprising:

capturing a series of x, y coordinate values generated by either a computer mouse or a digitizer tablet and using consecutive points to create an quadrant array that can be stored in computer storage according to the following pseudo code;

for i = 0 to N −

1  

 

xVal = x[ i + 1 ] −

x[ i ]  

 

yVal = y[ i + 1 ] −

y[ i ]  

 

QARRAY[ i ] = QUAD_1  

 

if xVal >

0 &

&

yVal >

0  

 

 

 

then QARRAY[ i ] = QUAD_1  

 

if xVal <

0 &

&

yVal >

0  

 

 

 

then QARRAY[ i ] = QUAD_2  

 

if xVal <

0 &

&

yVal <

0  

 

 

 

then QARRAY[ i ] = QUAD_3  

 

if xVal >

0 &

&

yVal <

0  

 

 

 

then QARRAY[ i ] = QUAD_4

where

x[i] and y[i] over the range i=0 to i=N−

1 is the discrete representation of a line,

QARRAY[i] over the range i=0 to i=N−

2 is the quadrant array,

QUAD_—

1, QUAD_—

2, QUAD_—

3, and QUAD_—

4 are integers, and

xVal and yVal are integers, and

N is the number of points.

2. A method for comparing two quadrant arrays comprising:

calculating the difference between the quadrant array sizes according to the following relationships;

diff=LC2*errorThreshold

LC1>

=LC2−

diff &

&

LC1<

=LC2+diff

where

errorThreshold is a decimal number from 0 to 1 inclusive,

LC1 represents the smallest quadrant array size,

LC2 represents the largest quadrant array size, and

diff is the error difference calculated by taking LC2 multiply that by errorThreshold.

3. A method for comparing two quadrant arrays comprising:

calculating the number of matched quadrant elements of two quadrant arrays according to the following pseudo code;

PQM = 0 QM = 0 for k = 0 to k <

30  

 

for i = 0 to i <

LC1 −

k  

 

 

 

if L1 [ i ] == L2[ i + k ]  

 

 

 

 

 

increment PQM  

 

 

 

if i <

LC1 −

k  

 

 

 

 

 

break  

 

if PQM >

QM  

 

 

 

then QM = PQM  

 

QM = 0  

 

If k == 30  

 

 

 

break

where

L1[i] and L2[i] are quadrant arrays,

PQM is the previous number of quadrant matches,

QM is the number of quadrant matches,

LC1 is the smallest number of points,

k ranges from 0 to 30 inclusive, and

i ranges from 0 to i<

LC1−

k.

4. A method for comparing a first continuous line to a second continuous line, comprising the steps of:

forming a first quadrant array from first data of said first continuous line;

forming a second quadrant array from second data of said second continuous line;

said first-quadrant array being formed from said first data at a first time and a second time;

said second quadrant array being formed from said second data at a third time and a fourth time, and

determining whether the first line and the second line are similar based upon a number of matched quadrant elements front the first quadrant array first data of said first continuous line and the second quadrant array from the second data of said second continuous line.

5. A method for comparing a first continuous line to a second continuous line as in claim 4, wherein the method includes the step of determining whether said first continuous line and said second continuous line are similar based upon a comparison of said first quadrant array and said second quadrant array.

6. A method for comparing a first continuous line to a second continuous line as in claim 4, wherein the method includes the step of adjusting a sampling interval to determine said first time and said second time.

7. A method for comparing a first continuous line to a second continuous line as in claim 4, wherein the method includes the step of determining quadrant array elements, from consecutive time intervals.

8. A method for comparing a first continuous line to a second continuous line as in claim 4, wherein the method includes the step of determining a largest array size from said first quadrant array and said second quadrant array.

9. A method for comparing a first continuous line to a second continuous line as in claim 8, wherein the method includes the step of determining a smallest array size from said first quadrant array and said second quadrant array.

10. A method for comparing a first continuous line to a second continuous line as in claim 9, wherein the method includes the step of determining if said largest array size and said small array size is within a predetermined range to determine a quadrant match.

11. A method for comparing a first continuous line to a second continuous line as in claim 10, wherein the method includes the step of determining the number of quadrant matches.