US 8,553,293 B2 · Image interpolation apparatus and a computer readable storage medium storing instructions of a computer program

Abstract

An image interpolation apparatus includes an extracting unit, temporal interpolation calculators, pattern matching units, and an output unit. The extracting unit extracts pixels around the missing pixels in order to form a basic frame and comparative frames. Each temporal interpolation calculator corresponds to each comparative frame, and calculates a temporal interpolated pixel for each comparative frame based on signal levels and variation of the signal levels. Each pattern matching unit corresponds to each comparative frame, inserts the temporal interpolated pixel of each comparative frame to the missing pixel, calculates difference of between each of the pixels in the basic frame and each of the corresponding pixels in the comparative frame, and sums up the differences for all pixels in absolute value to obtain sums for all comparative frames respectively. The output unit outputs the temporal interpolated pixel having a minimum sum among the sums as a final interpolated pixel.

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Claims25

Dependent claims

An image interpolation apparatus formed by connecting contact image sensors to interpolate a missing pixel, each of the contact image sensors being formed by arranging scan elements in a line, the missing pixel existing between the contact image sensors, comprising:

an extracting unit for extracting pixels around the missing pixels in order to form a basic frame and comparative frames, the basic frame being formed by at least three pixels including the missing pixel, the missing pixel being located at a head or tail of the pixels in the basic frame, each of the comparative frames including the same number of the pixels as the basic frame, wherein at least one pixel of the pixels in one comparative frame does not overlap the pixels in the other comparative frames;
temporal interpolation calculators, each temporal interpolation calculator corresponding to each of the comparative frames, and calculating a temporal interpolated pixel for each of the comparative frames based on signal levels and a variation of the signal levels in terms of a first pixel group and a second pixel group, the first pixel group including adjacent pixels of the missing pixel in the basic frame, the second pixel group including an edge pixel corresponding to the missing pixel and adjacent pixels of the edge pixel in the comparative frame;
pattern matching units, each pattern matching unit corresponding to each of the comparative frames, inserting the temporal interpolated pixel of each comparative frame to the missing pixel, calculating difference between each of the pixels in the basic frame and each of the corresponding pixels in the comparative frame, and summing up the differences for all pixels in absolute value to obtain sums for all comparative frames respectively;
and
an output unit outputting the temporal interpolated pixel having a minimum sum among the sums as a final interpolated pixel.

2 more elements

an extracting unit for extracting pixels around the missing pixels in order to form a basic frame and comparative frames, the basic frame being formed by at least three pixels including the missing pixel, the missing pixel being located at a head or tail of the pixels in the basic frame, each of the comparative frames including the same number of the pixels as the basic frame, wherein at least one pixel of the pixels in one comparative frame does not overlap the pixels in the other comparative frames;
temporal interpolation calculators, each temporal interpolation calculator corresponding to each of the comparative frames, and calculating a temporal interpolated pixel for each of the comparative frames based on signal levels and a variation of the signal levels in terms of a first pixel group and a second pixel group, the first pixel group including adjacent pixels of the missing pixel in the basic frame, the second pixel group including an edge pixel corresponding to the missing pixel and adjacent pixels of the edge pixel in the comparative frame;
pattern matching units, each pattern matching unit corresponding to each of the comparative frames, inserting the temporal interpolated pixel of each comparative frame to the missing pixel, calculating difference between each of the pixels in the basic frame and each of the corresponding pixels in the comparative frame, and summing up the differences for all pixels in absolute value to obtain sums for all comparative frames respectively;
a minimum detection unit for selecting a minimum sum among the sums outputted from the pattern matching units;
a linear interpolation unit for calculating a linear interpolated pixel according to a gradient of the pixels which exist in both sides of the missing pixel;
and
a switching unit outputting the temporal interpolated pixel from the minimum detection unit as a final interpolated pixel if the minimum sum from the minimum detection unit is smaller than a threshold, and outputting the linear interpolated pixel from the linear interpolation unit as the final interpolated pixel, if the minimum sum from the minimum detection unit is larger than the threshold.

4 more elements

an extracting unit for extracting pixels around the missing pixels in order to form a basic frame and comparative frames, the basic frame being formed by at least three pixels including the missing pixel, the missing pixel being located at a head or tail of the pixels in the basic frame, each of the comparative frames including the same number of the pixels as the basic frame, wherein at least one pixel of the pixels in one comparative frame does not overlap the pixels in the other comparative frames;
temporal interpolation calculators, each temporal interpolation calculator corresponding to each of the comparative frames, and calculating a temporal interpolated pixel for each of the comparative frames based on signal levels and a variation of the signal levels in terms of a first pixel group and a second pixel group, the first pixel group including adjacent pixels of the missing pixel in the basic frame, the second pixel group including an edge pixel corresponding to the missing pixel and adjacent pixels of the edge pixel in the comparative frame;
pattern matching units, each pattern matching unit corresponding to each of the comparative frames, inserting the temporal interpolated pixel of each comparative frame to the missing pixel, calculating difference of between each of the pixels in the basic frame and each of the corresponding pixels in the comparative frame, and summing up the differences for all pixels in absolute value to obtain sums for all comparative frames respectively;
a minimum detection unit for selecting a minimum sum among the sums outputted from the pattern matching units;
a linear interpolation unit for calculating a linear interpolated pixel according to a gradient of the pixels which exist in both sides of the missing pixel;
a level difference calculator calculating an average value of the pixels which exist in one side of the missing pixel and another average value of the pixels which exist in another side of the missing pixel, and calculating and outputting difference of the average values as a difference of signal levels;
and
a switching unit outputting the temporal interpolated pixel from the minimum detection unit as a final interpolated pixel if the difference of the signal levels is smaller than a threshold, and outputting the linear interpolated pixel from the linear interpolation unit as the final interpolated pixel, if the difference of the signal levels is larger than the threshold.

5 more elements

A method for interpolating a missing pixel of an image obtained from connected contact image sensors, each of the contact image sensors being formed by arranging scan elements in a line, the missing pixel existing between the contact image sensors, comprising:

extracting pixels around the missing pixels in order to form a basic frame and comparative frames, the basic frame being formed by at least three pixels including the missing pixel, the missing pixel being located at a head or tail of the pixels in the basic frame, each of the comparative frames including the same number of the pixels as the basic frame, wherein at least one pixel of the pixels in one comparative frame does not overlap the pixels in the other comparative frames;
calculating a temporal interpolated pixel for each of the comparative frames based on signal levels and a variation of the signal levels in terms of a first pixel group and a second pixel group, the first pixel group including adjacent pixels of the missing pixel in the basic frame, the second pixel group including an edge pixel corresponding to the missing pixel and adjacent pixels of the edge pixel in the comparative frame;
inserting the temporal interpolated pixel of each comparative frame to the missing pixel, calculating a difference between each of the pixels in the basic frame and each of the corresponding pixels in the comparative frame, and summing up the differences for all pixels in absolute value to obtain sums for all comparative frames respectively;
and
outputting the temporal interpolated pixel having a minimum sum among the sums as a final interpolated pixel.

2 more elements

Dependencies are inferred from the claim text.

Description9,551 words

Summary2,151 words

#This application is based upon and claims the benefit of priority from the Japanese Patent Application No. 2010-043701, filed on Mar. 1, 2010, and the Japanese Patent Application No. 2009-115531, filed on May 12, 2009, the entire contents of which are incorporated herein by reference.

#1. Field

#The present invention relates to an image interpolation apparatus and A computer readable storage medium storing instructions of a computer program.

Brief description of the drawings27 figures

#FIG. 1 is a figure showing an interpolation of a frame scanned by a contact image sensor;

#FIG. 2 is a figure explaining fundamental operation of the pattern matching;

#FIG. 3 is a figure explaining operation of the interpolation;

Detailed description6,929 words

#The embodiments will be explained with reference to the accompanying drawings.

#FIG. 1 is a figure showing an interpolation of a frame scanned by a contact image sensor. In the embodiments, a pattern matching is performed with respect to each line in a horizontal direction (main scanning direction). The missing pixel is interpolated based on the pixels in the line including the missing pixel. Similarly, the other missing pixel in other line is interpolated based on the pixels in the other line. This interpolation is repeated along a vertical direction (sub-scanning direction).

#(Fundamental Operation)

Facts

Application

12/769,985Filed 29 Apr 2010

Priority

JP P2009-11553112 May 2009

Published

US 2010/0290092 A118 Nov 2010

Granted

8 Oct 2013

Term ends

23 May 2032

Estimated · how

20 years from earliest known nonprovisional domestic filing plus recorded patent term adjustment, including 755 days of adjustment. Maintenance-fee lapses, terminal disclaimers and statutory extensions have not been checked. The continuity chain may be incomplete; this is not an enforceability determination.

Classification4 codes

H04N 1/401
Picture signal circuits: compensating positionally unequal response of the pick-up or reproducing head
G06T 3/4007
Scaling of whole images or parts thereof, e.g. expanding or contracting: based on interpolation, e.g. bilinear interpolation
H04N
Pictorial communication
G06T
Image data processing or generation, in general

Timeline

12 May 2009Priority claimedJP P2009-115531
29 Apr 2010Application filedUS 12/769,985
14 Jun 2010Assigned to Toshiba Design & Manufacturing Service Corporationassignment of assignor's interest
18 Nov 2010PublishedUS 2010/0290092 A1
8 Oct 2013GrantedUS 8,553,293 B2
12 Oct 2026TodayWithin its term
23 May 2032Term endsEstimated, includes 755 days of adjustment

Image interpolation apparatus and a computer readable storage medium storing instructions of a computer program

Life of this patent

Image interpolation apparatus and a computer readable storage medium storing instructions of a computer program

Life of this patent

Life of this patent

Abstract

Drawings

Drawings

Claims25

Description9,551 words

Drawings

Classification4 codes

Life of this patent

Description9,551 words