JPH11168622A - Image processor, image processing method and storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image processor which is capable of conducting an interpolation processing to adequately enhanceable edge parts of an image. SOLUTION: This image processor has an interpolation coefficient generating means 12 that receives a set high resolution rate and generates an interpolation coefficient, in response to the received high resolution rate and a tilt information extract means 104 that extracts tilt information between pixels in a received low resolution image. A correction coefficient generated by the interpolation coefficient generating means 102 and the tilt information extracted by the tilt information extract means 104 are given to a correction means 106, which applies a prescribed arithmetic processing to the interpolation coefficient, based on the detected tilt information to correct the correction coefficient. In this correction, the interpolation coefficients applied to pixels of an edge first half are corrected to be larger and the interpolation coefficients applied to pixels of an edge latter half are corrected to be smaller.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing apparatus, an image processing method, and a storage medium for performing image processing such as enlargement processing on an input image.

[0002]

2. Description of the Related Art Some printers are provided with an image scaling function for enlarging input image information. The image scaling function can enlarge and output the input image information. . In a video camera, an electronic zoom function for electronically enlarging a captured subject image is provided, and the enlarged subject image can be recorded and displayed by the electronic zoom function.

In the above-described image scaling function, electronic zoom function, and the like, an interpolation coefficient for generating an interpolation pixel between adjacent pixels is calculated, and an interpolation process for generating an interpolation pixel using the interpolation coefficient is performed. ing. As this interpolation processing, a so-called linear interpolation processing is used, in which the interpolation coefficient is uniformly determined according to the distance between each adjacent pixel and the interpolation pixel inserted therebetween.

[0004]

However, in the above-described linear interpolation processing, the interpolation coefficient is determined uniformly according to the distance between each adjacent pixel and the interpolation pixel inserted therebetween. In some cases, the inclination of the edge portion becomes dull, and the edge portion of the image cannot be sufficiently enhanced and enlarged.

An object of the present invention is to provide an image processing apparatus, an image processing method, and a storage medium capable of performing an interpolation process capable of sufficiently enhancing an edge portion of an image.

[0006]

According to the first aspect of the present invention,
In an image processing apparatus capable of converting a low-resolution image into a high-resolution image corresponding to a set high-resolution rate by interpolation processing, the set high-resolution rate and a distance between pixels in the low-resolution image Interpolation coefficient generation means for generating an interpolation coefficient for calculating an interpolation pixel based on the above, inclination information detection means for detecting inclination information between pixels in the low-resolution image, and the inclination information detection means Interpolation coefficient correction means for correcting the interpolation coefficient generated by the interpolation coefficient generation means based on the inclination information,
An interpolation process is performed on the low-resolution image using the interpolation coefficient corrected by the interpolation coefficient correction unit, and an image obtained by the interpolation process is output as the high-resolution image.

According to a second aspect of the present invention, there is provided a storage means for storing an input image, and an image stored in the storage means is enlarged to a set magnification by address control of the storage means. An image processing apparatus that can generate an enlarged image by reading and performing an interpolation process on the read image; a tilt information detecting unit that detects tilt information between pixels in the input image; An enlargement ratio variable control unit that variably controls the value of the set enlargement ratio for each pixel of the image read from the storage unit according to the inclination information detected by the information detection unit. .

According to a third aspect of the present invention, there is provided a storage means for storing an input image, and an image stored in the storage means is enlarged to a set enlargement ratio by address control of the storage means. Reading, in an image processing apparatus capable of generating an enlarged image by performing an interpolation process on the read image, including an inclination information detecting means for detecting inclination information between pixels in the input image, An address value of the storage means used for the address control and an interpolation coefficient used for the interpolation processing are controlled in accordance with the inclination information detected by the inclination information detecting means.

[0009] According to a fourth aspect of the present invention, an object is imaged,
Imaging means for generating and outputting a video signal of the imaged subject; storage means for storing the video signal output from the imaging means; and a video signal output from the imaging means according to a set magnification. An interpolation coefficient generating means for generating an interpolation coefficient used for interpolation processing for enlarging the image data. The image processing apparatus further comprises: an inclination information detecting means for detecting inclination information between pixels in a video signal generated by the imaging means. The output timing of the video signal from the imaging unit, an address value for reading the video signal from the storage unit, and the interpolation coefficient generation unit, according to the tilt information detected by the tilt information detection unit. The correction of the generated interpolation coefficient is controlled.

According to a fifth aspect of the present invention, there is provided an image processing method for converting a low-resolution image into a high-resolution image corresponding to a set high-resolution rate by interpolation processing. Generating an interpolation coefficient for calculating an interpolation pixel based on a ratio and a distance between pixels in the low-resolution image; detecting inclination information between pixels in the low-resolution image; Correcting the interpolation coefficient based on the obtained inclination information, performing interpolation processing on the low resolution image using the corrected interpolation coefficient, and outputting an image obtained by the interpolation processing as the high resolution image. And a step of performing

According to a sixth aspect of the present invention, an input image is stored in a storage means, and an image stored in the storage means is read out by an address control of the storage means so as to be enlarged to a set magnification. In an image processing method for generating an enlarged image by performing an interpolation process on the read image, a step of detecting inclination information between pixels in the input image, Variably controlling the value of the set enlargement ratio for each pixel of the image read from the storage means.

According to a seventh aspect of the present invention, an input image is stored in a storage means, and an image stored in the storage means is read out by an address control of the storage means so as to be enlarged to a set magnification. In an image processing method for generating an enlarged image by performing an interpolation process on the read image, a step of detecting inclination information between pixels in the input image, An address value of the storage means used for the address control and an interpolation coefficient used for the interpolation processing are controlled.

[0013] The invention according to claim 8 captures an image of a subject,
Imaging means for generating and outputting a video signal of the imaged subject; storage means for storing the video signal output from the imaging means; and a video signal output from the imaging means according to a set magnification. In an image processing method used in an image processing apparatus having an interpolation coefficient generation means for generating an interpolation coefficient used for interpolation processing for enlarging an image, inclination information between pixels in a video signal generated by the imaging means is detected. And an output value of the video signal from the imaging unit, an address value for reading the video signal from the storage unit, and the interpolation coefficient generation unit in accordance with the tilt information detected by the tilt information detection unit. Controlling the correction of the interpolation coefficient generated by the above.

According to a ninth aspect of the present invention, there is provided a program for constructing, on an apparatus, an image processing system for converting a low-resolution image into a high-resolution image corresponding to a set high-resolution rate by interpolation processing. An interpolation coefficient generation module that generates an interpolation coefficient for calculating an interpolation pixel based on the set high resolution rate and the distance between pixels in the low resolution image, A tilt information detection module for detecting tilt information between pixels in the low resolution image, and an interpolation coefficient for correcting an interpolation coefficient generated by the interpolation coefficient generation module based on the tilt information detected by the tilt information detection module A correction module and an interpolation coefficient corrected by the interpolation coefficient correction module. Performed during processing, characterized in that it comprises an interpolation processing module for outputting an image obtained by the interpolation process as the image of the high resolution.

According to a tenth aspect of the present invention, an image stored in a storage unit is enlarged to a set enlargement ratio by controlling an address of the storage unit on an apparatus having a storage unit for storing an input image. And a storage medium storing a program for constructing an image processing system capable of generating an enlarged image by performing an interpolation process on the read image, wherein the program executes A tilt information detecting module for detecting tilt information between pixels, and a value of the set magnification ratio according to the tilt information detected by the tilt information detecting module, for each pixel of the image read from the storage unit. And a variable magnification control module for performing variable control.

According to an eleventh aspect of the present invention, an image stored in a storage unit is enlarged to a set magnification ratio by controlling an address of the storage unit on an apparatus having a storage unit for storing an input image. And a storage medium storing a program for constructing an image processing system capable of generating an enlarged image by performing an interpolation process on the read image, wherein the program executes A tilt information detecting module for detecting tilt information between pixels, an address value of the storage means used for the address control according to the tilt information detected by the tilt information detecting module, and an interpolation coefficient used for the interpolation process. And a control module for controlling

According to a twelfth aspect of the present invention, there is provided an image capturing means for capturing an image of a subject, generating and outputting a video signal of the captured subject, a storage means for storing a video signal output from the image capturing means, A program executable on an image processing apparatus having interpolation coefficient generation means for generating an interpolation coefficient used for interpolation processing for enlarging a video signal output from an imaging means according to a set enlargement ratio is stored. In the storage medium, the program may include: a tilt information detection module that detects tilt information between pixels in a video signal generated by the imaging unit; and the imaging unit according to the tilt information detected by the tilt information detection module. Output timing of the video signal from the memory, an address value for reading the video signal from the storage means, and generation of the interpolation coefficient Characterized in that it comprises a control module for controlling the correction of the interpolation coefficients generated by the step.

[0018]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) FIG. 1 is a block diagram showing a configuration of an image processing apparatus according to an embodiment of the present invention.

The image processing apparatus, as shown in FIG. 1, receives the set high-resolution rate, and generates an interpolation coefficient according to the input high-resolution rate.
Tilt information extracting means 10 for inputting a low resolution image and extracting tilt information between pixels in the input low resolution image
And 4. Here, the set high resolution ratio is a value selected from a predetermined range of the high resolution ratio set in advance, and the value of the interpolation coefficient generated according to the value of the high resolution ratio is Determined uniquely. That is, the number of interpolation pixels is uniquely determined according to the value of the high-resolution rate, and an interpolation coefficient corresponding to the distance between the pixels of the input image into which the determined number of interpolation pixels is inserted is generated. become.

The correction coefficient generated by the interpolation coefficient generation means 102 and the inclination information extracted by the inclination information extraction means 104 are input to the correction means 106. The correction means 106
Based on the tilt information detected by the tilt information detecting means 104, a predetermined calculation process is performed on the interpolation coefficient generated by the interpolation coefficient generating means 102 to correct the correction coefficient. From the inclination information, the center of the edge, the width of the inclination, the magnitude of the inclination, and the like are obtained. For the edge, the first half of the edge is formed with respect to the pixel at the center of the edge. The interpolation coefficient applied to the pixel to be corrected is corrected to have a larger value, and the interpolation coefficient applied to the pixel is corrected to be a smaller value for the latter half of the edge. In this correction, the correction is performed by adding or subtracting a predetermined value to or from the interpolation coefficient generated by the interpolation coefficient generation unit 102 based on the slope information, or by multiplying the generated interpolation coefficient by a predetermined value based on the slope information.

The correction coefficient corrected by the correction means 106 is input to the interpolation processing means 108 together with the low-resolution image.
The interpolation processing unit 108 performs an interpolation process on the low-resolution image using the correction coefficient corrected by the correction unit 106.
A high-resolution image corresponding to the high-resolution rate set by the interpolation processing is generated and output.

Next, the processing in this image processing apparatus is shown in FIG.
This will be specifically described with reference to FIG. FIG. 2 is a diagram for specifically explaining processing in the image processing apparatus of FIG.

For example, as shown in FIG.
Consider a case where the resolution of a low-resolution image including each pixel of B, C,..., I is increased three times in the horizontal and vertical directions. In this case, for a three times higher resolution ratio, a0
Each interpolated pixel of 1, a02, a10, a11, a12,... Is generated. For example, each of the interpolated pixels a01, a02, a10, and a11 has the following (1) to (4) in the conventional interpolation processing.
Generated based on the formula.

A01 = A * (2/3) + B * (1/3) (1) a02 = A * (1/3) + B * (2/3) (2) a10 = A * (2 /) 3) + D * (1/3) (3) a11 = A * (4/9) + B * (2/9) + D * (2/9) + E * (1/9) (4) Numerical values in parentheses are interpolation coefficients, and the interpolation coefficients are the interpolation coefficient generation means 102 in the image processing apparatus.
Is the same as the interpolation coefficient generated by

Here, when each of the pixels A, B, and C such that the signal level of each of the pixels A, B, and C sequentially increases constitutes the edge portion of the image, the conventional interpolation processing and the image processing by the present image processing apparatus are performed. Compare with interpolation processing. In the conventional interpolation processing, as shown in FIG. 2B, the interpolation pixels a01, a02, b01, and b02 between the pixels A, B, and C have the levels of the pixels A, B, and
It is generated so as to ride on a straight line connecting C. On the other hand, in the interpolation processing by the image processing apparatus, the correction means 10
In step 6, the interpolation coefficient (same as the interpolation coefficient used in the conventional interpolation processing) is subjected to predetermined arithmetic processing based on the inclination information for each of the pixels A, B, and C to correct the correction coefficient. An interpolation process is performed on the low-resolution image using the correction coefficient corrected in 108. Accordingly, in the interpolation processing by the image processing apparatus, as shown in FIG. 2C, the center of the edge, the width of the inclination, the magnitude of the inclination, and the like are obtained from the inclination information for each of the pixels A, B, and C. With the pixel B being the center of the edge as a boundary, the interpolation coefficient applied to the pixel A is corrected to a larger value for the first half of the edge, and the interpolation coefficient applied to the pixel B is corrected for the second half of the edge. Correct to a smaller value. For example, the interpolation coefficient generated by the interpolation coefficient generation means 102 may have a predetermined value, for example, 1
/ 3 is added or subtracted based on the slope information to calculate an interpolation coefficient,
An interpolation pixel is obtained using the interpolation coefficient. The interpolation pixels a01, a02, b01, and b02 obtained in this manner are represented by the following equations (5) to (8).

A01 = A * (2/3 + ／) + B * (1 / 3-1 / 3) = A * (3/3) + B * (0/3) (5) a02 = A * (1) / 3 + 1/3) + B * (2 / 3-1 / 3) = A * (2/3) + B * (1/3) (6) b01 = B * (2 / 3-1 / 3) + C * (1/3 + 1/3) = B * (1/3) + C * (2/3) (7) b02 = B * (1 / 3-1 / 3) + C * (2/3 + 1/3) = B * (0/3) + C * (3/3) (8) The final numerical value in parentheses in each of the above equations is the corrected interpolation coefficient, and the interpolation processing is performed using the corrected interpolation coefficient. Is performed, each interpolated pixel a01, a02 approaches the value of the pixel A, and each interpolated pixel b01, b02 approaches the value of the pixel C, as compared with the conventional linear interpolation processing. Becomes steep. That is, it is possible to perform an interpolation process capable of sufficiently enhancing the edge portion of the image.

In this embodiment, the correction coefficient generating means 102, the inclination information extracting means 104, and the correcting means 1
06, it is possible to configure the interpolation processing means 108 by hardware, or to configure each of the means 102, 104, 106 and 108 by software. Each means 102, 1
When the components 04, 106, and 108 are configured by software, application programs for configuring the units 102, 104, 106, and 108 can be stored in a storage medium such as an HDD, and the application can be read and executed. A simple personal computer may be used.

Second Embodiment Next, a second embodiment of the present invention will be described with reference to FIGS. FIG. 3 is a block diagram showing the configuration of a second embodiment of the image processing apparatus according to the present invention, and FIG. 4 is a view for explaining the operation of the inclination detecting means 20 of the image processing apparatus shown in FIG.

As shown in FIG. 2, the image processing apparatus according to the present embodiment includes a memory 2 for storing an input signal which is an image signal, and a tilt detecting means 20 for detecting tilt information between pixels in the input signal. Have.

The inclination detecting means 20 includes a difference value detecting means 42
And edge information extracting means 44. The difference value detection means 42 calculates a difference value between pixels in the input signal, and detects an edge portion based on the calculated difference value. Specifically, when the difference value between the pixels is large, a portion including the pixel is determined to be an edge portion, and a portion including the pixel is detected as an edge portion. Note that if the difference value between the pixel and the pixel one line before is obtained as the difference value between the pixels, the edge portion can be detected with higher accuracy.

When an edge portion is detected, a difference value between pixels corresponding to the edge portion is converted to edge information extracting means 44.
Is input to The edge information extracting means 44 obtains information such as the magnitude of the inclination of the edge portion, the width of the edge portion, and the center position of the edge portion based on the input difference value, and controls the enlargement ratio set from each obtained information. To generate a gain adjustment signal. This gain adjustment signal is input to gain control means 22.

The gain control means 22 inputs an enlargement ratio setting signal indicating an enlargement ratio with respect to the input signal,
Based on the gain adjustment signal from 0, the level of the input magnification setting signal is variably controlled and output. That is, the value of the enlargement ratio is variably controlled based on the gain adjustment signal. For example,
At the center of the edge, the enlargement ratio setting signal is controlled so that the value of the enlargement ratio is smaller than the initial value according to the gain adjustment signal, and at the periphery of the edge, the value of the enlargement ratio is adjusted to the initial value according to the gain adjustment signal. The enlargement ratio setting signal is controlled so as to have a larger value.

The magnification setting signal controlled by the gain control means 22 is input to the vertical interpolation coefficient generation means 8 and the horizontal direction interpolation coefficient generation means 10. The vertical interpolation coefficient generating means 8 generates a vertical XRE control signal and a vertical interpolation coefficient (vertical interpolation coefficient) according to the input enlargement ratio setting signal. The vertical XRE control signal is a control signal for stopping the operation of incrementing the vertical read address for the memory 2, and the control signal is input to the memory control signal generation means 4. In contrast, the vertical interpolation factor is
It is input to the vertical interpolation processing circuit 14. The horizontal direction interpolation coefficient generation means 10 generates a horizontal XRE control signal and a horizontal direction interpolation coefficient (horizontal interpolation coefficient) according to the input enlargement ratio setting signal. The horizontal XRE control signal is a control signal for stopping the increment operation of the horizontal read address for the memory 2, and the control signal is input to the memory control signal generation means 4. On the other hand, the horizontal interpolation coefficient is input to the horizontal interpolation processing circuit 16.

The memory control signal generation means 4 generates a write address and a read address for controlling writing and reading of an input signal to and from the memory 2. When reading the input signal from the memory 2, the read address in each direction is controlled based on the vertical XRE control signal and the horizontal XRE control signal input from the vertical interpolation coefficient generation means 8 and the horizontal direction interpolation coefficient generation means 10, respectively. That is, by stopping the increment operation of the read address in each direction based on the vertical XRE control signal and the horizontal XRE control signal, the memory 2 corresponding to the controlled enlargement ratio is controlled.
Is read out from the memory.

The signal read from the memory 2 is input to the vertical interpolation processing circuit 14. The vertical interpolation processing circuit 14
The delay unit 72 includes a delay unit 72 and an interpolation unit 74. The delay unit 72 delays the signal read from the memory 2 by one horizontal scanning period and outputs the delayed signal. The interpolation means 74 is a memory 2
, The signal (delay signal) output from the delay means 72 as the signal B, and the vertical interpolation coefficient from the vertical interpolation coefficient generation means 8 as the signal K, and the following (9) The arithmetic processing according to the expression is performed.
By this arithmetic processing, vertical interpolation processing using a vertical interpolation coefficient corresponding to the controlled enlargement ratio is performed, and a signal S after the interpolation processing is output.

S = (1−K) * A + K * B (9) The signal output from the vertical interpolation processing circuit 14 is input to the horizontal interpolation processing circuit 16. The horizontal interpolation processing circuit 16
It is composed of a delay means 82 for delaying the signal output from the vertical interpolation processing circuit 14 by one pixel and outputting the delayed signal, and an interpolation means 84. The interpolation means 84 is a signal from the vertical interpolation processing circuit 14 and a signal output from the delay means 82 (delayed signal).
The horizontal interpolation coefficient from the horizontal interpolation coefficient generation means 10 is taken in, and the same arithmetic processing as the arithmetic processing according to the above equation (9) is performed. By this calculation processing, horizontal interpolation processing using a horizontal interpolation coefficient corresponding to the controlled enlargement ratio is performed, and a signal after this interpolation processing, that is, a signal enlarged to the set enlargement ratio, is output.

Next, the operation of the inclination detecting means 20 in this embodiment will be described with reference to FIG.

For example, when an edge signal of the input signal shown in FIG.
In the difference value detection means 42, as shown in FIG.
A difference value from the pixel one pixel before is calculated, and it is determined from the difference value that the current input signal is a signal corresponding to an edge portion. The difference value corresponding to the edge portion is input to the edge information extracting means 44. In the edge information extracting means 44, as shown in FIG. 4 (c), based on the input difference value, the gain adjustment for controlling the value of the enlargement ratio to be smaller than the initial value at the center of the edge. A gain adjustment signal for controlling the signal so that the value of the enlargement factor becomes larger than the initial value in the peripheral portion of the edge is generated.

In the gain control means 22 to which the gain adjustment signal generated as described above is inputted, as shown in FIG. 4D, the value of the enlargement ratio becomes smaller than the initial value at the center of the edge. The enlargement ratio setting signal is controlled so that the value of the enlargement ratio becomes larger than the initial value in accordance with the gain adjustment signal in the peripheral portion of the edge.

As described above, at the center of the edge, the value of the enlargement ratio is controlled to be smaller than the initial value, and at the periphery of the edge, the value of the enlargement ratio is controlled to be larger than the initial value. Therefore, the edge portion of the enlarged image can be sufficiently emphasized.

In the present embodiment, each block such as the inclination detecting means 20 and the gain control means 22 is constituted by hardware, but each block may be constituted by software. In this case, the application program for configuring each block is HD
A personal computer or the like that can store the application in a storage medium such as D and read and execute the application may be used.

(Third Embodiment) Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 5 is a block diagram showing a configuration of an image processing apparatus according to a third embodiment of the present invention.

This embodiment shows an example in which the present invention is applied to a video camera having an electronic zoom function. Blocks having the same functions as those in the above-described second embodiment are denoted by the same reference numerals.
The description is omitted or simplified.

In the present embodiment, the inclination information between pixels in a picked-up video signal is detected, and the output timing of the video signal, the address value for reading the video signal from the memory, and the interpolation are determined according to the detected inclination information. Control of coefficient correction.

Specifically, as shown in FIG. 5, the video camera according to the present embodiment converts a video signal captured by the image sensor 32 into a digital video signal, with a TG 34 for controlling the driving of the image sensor 32. An AD 36 and a camera signal processing circuit 38 that performs predetermined processing (for example, luminance signal processing, color signal processing, and gamma correction) on the digital video signal from the AD 36.

A digital video signal (luminance signal or chrominance signal) subjected to predetermined processing by the camera signal processing circuit 38
Is input to the memory 40 and the inclination detecting means 20.
The inclination detecting means 20 obtains a difference value between pixels of the input digital video signal, and generates a gain adjustment signal for controlling an enlargement ratio set based on the difference value. This gain adjustment signal is input to gain control means 22. The gain control means 22 variably controls the level of the input magnification setting signal based on the gain adjustment signal from the inclination detection means 20 and outputs it. That is, in the center of the edge, the enlargement ratio setting signal is controlled so that the value of the enlargement ratio becomes smaller than the initial value in accordance with the gain adjustment signal, and in the periphery of the edge, the value of the enlargement ratio is adjusted in accordance with the gain adjustment signal. The enlargement ratio setting signal is controlled so as to be larger than the initial value.

The magnification setting signal controlled by the gain control means 22 is input to the vertical interpolation coefficient generation means 8 and the horizontal direction interpolation coefficient generation means 10. The vertical interpolation coefficient generating means 8 generates a vertical XRE control signal and a vertical interpolation coefficient (vertical interpolation coefficient) according to the input enlargement ratio setting signal. The vertical XRE control signal is a control signal for stopping the operation of incrementing the vertical read address for the TG 34, and the control signal is input to the TG 34. On the other hand, the vertical interpolation coefficient is input to the vertical interpolation processing circuit 14. The TG 34 controls reading in the vertical direction based on the vertical XRE control signal input from the vertical interpolation coefficient generating means 8 when reading a video signal from the image sensor 32. That is, by stopping the reading operation in the vertical direction based on the vertical XRE control signal, the reading in the vertical direction from the image sensor 32 according to the controlled magnification is performed.

The horizontal direction interpolation coefficient generating means 10 generates a horizontal XRE control signal and a horizontal direction interpolation coefficient (horizontal interpolation coefficient) in accordance with the input enlargement ratio setting signal. The horizontal XRE control signal is a control signal for stopping the operation of incrementing the horizontal read address for the memory 40, and the control signal is input to the memory control signal generation means 4. On the other hand, the horizontal interpolation coefficient is input to the horizontal interpolation processing circuit 16.

The memory control signal generating means 4 includes a memory 40
A write address and a read address for controlling writing and reading of a digital video signal to and from the digital video signal are generated. At the time of reading the input signal from the memory 40, the read address in the horizontal direction is controlled based on the horizontal XRE control signal input from the horizontal interpolation coefficient generation means 10. That is, by stopping the increment operation of the read address in the horizontal direction based on the horizontal XRE control signal, the read operation in the horizontal direction from the memory 40 according to the controlled enlargement ratio is performed.

The signal read from the memory 40 is input to the vertical interpolation processing circuit 14. Vertical interpolation processing circuit 14
Performs vertical interpolation processing using the vertical interpolation coefficient from the vertical interpolation coefficient generation means 8, that is, the vertical interpolation coefficient corresponding to the controlled enlargement ratio, and outputs a signal after the interpolation processing. The signal output from the vertical interpolation processing circuit 14 is input to the horizontal interpolation processing circuit 16. Horizontal interpolation processing circuit 16
Performs horizontal interpolation using the horizontal interpolation coefficient from the horizontal interpolation coefficient generation means 10, that is, the horizontal interpolation coefficient corresponding to the controlled enlargement ratio, and enlarges the signal after this interpolation processing, that is, the set enlargement ratio. The output signal is output.

As described above, the inclination information between pixels in the captured video signal is detected, and the output timing of the vertical video signal from the image sensor 32 and the horizontal timing from the memory 40 are detected in accordance with the detected tilt information. Since the correction of the address value for reading the video signal and the interpolation coefficient in each of the horizontal and vertical directions is controlled, as in the second embodiment, the value of the enlargement ratio is larger than the initial value at the center of the edge. Control is performed so that the value becomes smaller, and in the peripheral portion of the edge, the value of the enlargement ratio is controlled so as to be larger than the initial value, so that the edge portion of the enlarged image can be sufficiently emphasized.

(Fourth Embodiment) Next, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 6 is a block diagram showing a configuration of an image processing apparatus according to a fourth embodiment of the present invention. Note that blocks having the same functions as those in the above-described second embodiment are denoted by the same reference numerals, and description thereof will be omitted or simplified.

This embodiment is different from the above-described second embodiment in that the vertical interpolation coefficient generating means 8 uses the inclination detecting means 2
A vertical XRE control signal and a vertical interpolation coefficient are generated in accordance with the gain adjustment signal from 0 and the input enlargement ratio setting signal.
The difference is that the horizontal XRE control signal and the horizontal interpolation coefficient are generated according to the gain adjustment signal from 0 and the input enlargement ratio setting signal.

Therefore, similar to the above-described second embodiment,
At the center of the edge, the value of the enlargement ratio is controlled to be smaller than the initial value. At the periphery of the edge, the value of the enlargement ratio is controlled to be larger than the initial value. Can be emphasized enough.

(Fifth Embodiment) Next, a fifth embodiment of the present invention will be described with reference to FIGS. FIG. 7 is a block diagram showing a configuration of a fifth embodiment of the image processing apparatus of the present invention, and FIG. 8 is a block diagram showing a configuration of a vertical interpolation coefficient generation unit and a horizontal interpolation coefficient generation unit of FIG. Note that blocks having the same functions as those in the above-described second embodiment are denoted by the same reference numerals, and description thereof will be omitted or simplified.

The present embodiment is configured to perform a linear interpolation process when enlarging an input signal, and to increase the gain of the intermediate frequency band component of the signal of the enlarged image obtained by the linear interpolation process. .

More specifically, as shown in FIG. 7, an input signal which is an image signal is stored in a memory 2, and writing and reading of the input signal to and from the memory 2 are performed by writing from the memory control signal generating means 4. It is controlled by the address and the read address.

When reading the input signal from the memory 2, the memory control signal generating means 4 converts the vertical XRE control signal and the horizontal XRE control signal input from the vertical interpolation coefficient generating means 8 and the horizontal direction interpolation coefficient generating means 10, respectively. The read address in each direction is controlled on the basis of this. That is, the increment operation of the read address in each direction is stopped based on the vertical XRE control signal and the horizontal XRE control signal, and the signal is read from the memory 2 according to the controlled enlargement ratio.

The vertical interpolation coefficient generating means 8 generates a vertical XRE control signal and a vertical interpolation coefficient according to the input enlargement ratio setting signal. Specifically, as shown in FIG. 8, the vertical interpolation coefficient generating means 8 includes an adder 50 for inputting an enlargement ratio setting signal, a latch circuit 54 for holding an output from the adder 50, And a latch circuit 56 for holding the carry output of. The adder 50 adds the input enlargement ratio setting signal and the signal held by the latch circuit 54 for a predetermined period (for example, a period corresponding to a counting period of a predetermined value 256) for each horizontal scan. To stop the adding operation, return the added value to "0" again, and start the next adding operation. The added value at the time when a predetermined period has elapsed is output as a vertical interpolation coefficient via the latch circuit 54. The carry output signal 52 is output from the adder 50, and the carry output signal 52 is output as a vertical XRE control signal via a latch circuit 56. The vertical XRE control signal is supplied to the memory control signal generation means 4.
The vertical interpolation coefficients are input to the vertical interpolation processing circuit 14, respectively.

The horizontal direction interpolation coefficient generating means 10 generates a horizontal XRE control signal and a horizontal interpolation coefficient according to the input enlargement ratio setting signal. Horizontal interpolation coefficient generating means 1
0 has the same configuration as that of the vertical interpolation coefficient generation means 8 and also generates the horizontal XRE control signal and the horizontal interpolation coefficient in the same manner. The horizontal XRE control signal is sent to the memory control signal generating means 4 and the horizontal interpolation coefficient is sent to the horizontal interpolation processing circuit 16.
Respectively.

The signal read from the memory 2 is input to the vertical interpolation processing circuit 14. The vertical interpolation processing circuit 14
It is composed of a delay means 72 and an interpolation means 74, performs an arithmetic processing according to the above equation (9), and performs vertical interpolation processing according to the enlargement ratio by this arithmetic processing. The signal after this interpolation processing is input to the horizontal interpolation processing circuit 16. The horizontal interpolation processing circuit 16 includes a delay unit 82 and an interpolation unit 84, and performs the same arithmetic processing as the arithmetic processing according to the above equation (9). By this arithmetic processing, horizontal interpolation processing according to the enlargement ratio is performed, and the signal after the interpolation processing, that is, the signal enlarged to the set enlargement ratio, is input to the enhancer circuit 18.

The enhancer circuit 18 includes a BPF (Band Pass Filter) 92 and an adder 94. B
The PF 92 extracts and outputs a signal having an intermediate frequency band component in the input signal. The adder 94 has a BP
The signal from F92 and the signal from horizontal interpolation processing circuit 16 are added and output.

As described above, since the signal from the horizontal interpolation processing circuit 16 is a signal enlarged by the linear interpolation processing, the edge portion is dull and poor in resolution. By increasing the gain of the intermediate frequency band component by the enhancer circuit 18, a signal whose edge portion is emphasized can be obtained. Therefore, the edge portion of the enlarged image can be emphasized.

[0065]

As described above, according to the image processing apparatus of the first aspect, it is possible to calculate the interpolation pixel based on the set high resolution ratio and the distance between the pixels in the low resolution image. Interpolation coefficient generation means for generating an interpolation coefficient;
Tilt information detecting means for detecting tilt information between pixels in the low-resolution image; and interpolation coefficient correcting means for correcting an interpolation coefficient generated by the interpolation coefficient generating means based on the tilt information detected by the tilt information detecting means. The low-resolution image is interpolated using the interpolation coefficients corrected by the interpolation coefficient correction unit, and the image obtained by the interpolation processing is output as a high-resolution image. At this time, it is possible to perform an interpolation process capable of sufficiently enhancing the edge portion of the image.

According to the image processing apparatus of the present invention, the tilt information detecting means for detecting tilt information between pixels in the input image and the tilt information set in accordance with the tilt information detected by the tilt information detecting means. Since there is an enlargement ratio variable control unit that variably controls the value of the enlargement ratio for each pixel of the image read from the storage unit, when performing the enlargement process, the interpolation process that can sufficiently emphasize the edge portion of the image is performed. It can be carried out.

According to the third aspect of the present invention, there is provided an image processing apparatus having tilt information detecting means for detecting tilt information between pixels in an input image, and performing address control in accordance with the tilt information detected by the tilt information detecting means. Since the address value of the storage means used for the interpolation and the interpolation coefficient used for the interpolation processing are controlled, it is possible to perform the interpolation processing capable of sufficiently enhancing the edge portion of the image when performing the enlargement processing.

According to a fourth aspect of the present invention, there is provided an image processing apparatus having tilt information detecting means for detecting tilt information between pixels in a video signal generated by an imaging means, wherein the tilt information detected by the tilt information detecting means is provided. According to the control of the output timing of the video signal from the imaging means, the address value for reading the video signal from the storage means and the correction of the interpolation coefficient generated by the interpolation coefficient generation means, when performing the enlargement process In addition, it is possible to perform an interpolation process capable of sufficiently enhancing the edge portion of the image.

According to the image processing method of the fifth aspect, a step of generating an interpolation coefficient for calculating an interpolation pixel based on the set high resolution ratio and the distance between pixels in the low resolution image, A step of detecting inclination information between pixels in the low-resolution image, a step of correcting an interpolation coefficient based on the detected inclination information, and performing an interpolation process on the low-resolution image using the corrected interpolation coefficient. Outputting the image obtained by the interpolation process as a high-resolution image. Therefore, when performing the high-resolution process, it is possible to perform the interpolation process capable of sufficiently enhancing the edge portion of the image.

According to the image processing method of the sixth aspect, a step of detecting inclination information between pixels in the input image, and the step of storing the value of the set enlargement ratio according to the detected inclination information. A step of variably controlling each pixel of the image read from the means, it is possible to perform an interpolation process capable of sufficiently enhancing an edge portion of the image when performing the enlargement process.

According to the image processing method of the present invention, the step of detecting the inclination information between the pixels in the input image, the step of interpolating the address value of the storage means used for address control according to the detected inclination information and the interpolation. Since the interpolation coefficient used in the processing is controlled, it is possible to perform the interpolation processing capable of sufficiently enhancing the edge portion of the image when performing the enlargement processing.

According to the image processing method of the eighth aspect, the step of detecting the inclination information between the pixels in the video signal generated by the imaging means, and the step of detecting the image in accordance with the inclination information detected by the inclination information detection means The output timing of the video signal from the means, the step of controlling the address value for reading the video signal from the storage means and the correction of the interpolation coefficient generated by the interpolation coefficient generation means, when performing the enlargement processing, An interpolation process capable of sufficiently enhancing the edge portion of the image can be performed.

According to the storage medium of the ninth aspect, the program generates the interpolation coefficient for calculating the interpolation pixel based on the set high resolution rate and the distance between the pixels in the low resolution image. A coefficient generation module, a tilt information detection module that detects tilt information between pixels in a low-resolution image, and an interpolation that corrects an interpolation coefficient generated by the interpolation coefficient generation module based on the tilt information detected by the tilt information detection module Includes a coefficient correction module, and an interpolation processing module that performs an interpolation process on a low-resolution image using the interpolation coefficient corrected by the interpolation coefficient correction module, and outputs an image obtained by the interpolation process as a high-resolution image. Therefore, when performing the enlargement process, it is possible to perform the interpolation process that can sufficiently emphasize the edge portion of the image. .

According to the storage medium of the tenth aspect, the program is set according to the tilt information detecting module for detecting tilt information between pixels in the input image, and the tilt information detected by the tilt information detecting module. And an enlargement ratio variable control module for variably controlling the value of the enlargement ratio for each pixel of the image read from the storage means. It can be performed.

According to the storage medium of the eleventh aspect, the program is configured such that an inclination information detection module for detecting inclination information between pixels in an input image, and address control in accordance with the inclination information detected by the inclination information detection module. And a control module for controlling the address value of the storage means used for interpolation and the interpolation coefficient used for the interpolation processing.
When performing the enlargement process, it is possible to perform an interpolation process capable of sufficiently enhancing the edge portion of the image.

According to the storage medium of the twelfth aspect, the program includes a tilt information detecting module for detecting tilt information between pixels in a video signal generated by the imaging means, and a tilt information detected by the tilt information detecting module. According to the output timing of the video signal from the imaging means,
A control module for controlling the correction of the interpolation coefficient generated by the address value and the interpolation coefficient generation means for reading the video signal from the storage means, so that the edge portion of the image is sufficiently An interpolation process that can be emphasized can be performed.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of an embodiment of an image processing apparatus according to the present invention.

FIG. 2 is a diagram for specifically explaining processing in the image processing apparatus of FIG. 1;

FIG. 3 is a block diagram illustrating a configuration of an image processing apparatus according to a second embodiment of the present invention.

FIG. 4 is a diagram for explaining the operation of the inclination detecting means 20 of the image processing apparatus of FIG. 3;

FIG. 5 is a block diagram illustrating a configuration of an image processing apparatus according to a third embodiment of the present invention.

FIG. 6 is a block diagram illustrating a configuration of an image processing apparatus according to a fourth embodiment of the present invention.

FIG. 7 is a block diagram illustrating a configuration of an image processing apparatus according to a fifth embodiment of the present invention.

8 is a block diagram showing a configuration of a vertical interpolation coefficient generation unit and a horizontal interpolation coefficient generation unit of FIG.

[Explanation of symbols]

 2, 40 memory 4 memory control signal generation means 8 vertical interpolation coefficient generation means 10 horizontal interpolation coefficient generation means 14 vertical interpolation processing circuit 16 horizontal interpolation processing circuit 18 enhancer circuit 20 inclination detection means 22 gain control means 32 image sensor 34 TG 38 camera Signal processing circuit 102 Interpolation coefficient generation means 104 Slope information extraction means 106 Correction means 108 Interpolation processing means

Claims (12)

[Claims] 1. An image processing apparatus capable of converting a low-resolution image into a high-resolution image corresponding to a set high-resolution rate by interpolation processing, wherein the set high-resolution rate and the low-resolution image are An interpolation coefficient generation unit for generating an interpolation coefficient for calculating an interpolation pixel based on the distance between pixels, a tilt information detection unit for detecting tilt information between pixels in the low-resolution image, and the tilt information detection. Interpolation coefficient correction means for correcting the interpolation coefficient generated by the interpolation coefficient generation means based on the inclination information detected by the means, and the low resolution of the low resolution using the interpolation coefficient corrected by the interpolation coefficient correction means An image processing apparatus which performs an interpolation process on an image and outputs an image obtained by the interpolation process as the high-resolution image. 2. An image processing apparatus, comprising: storage means for storing an input image; reading out an image stored in the storage means by an address control of the storage means so as to be enlarged to a set enlargement ratio; An image processing apparatus capable of generating an enlarged image by performing an interpolation process on the input image, a tilt information detecting unit that detects tilt information between pixels in the input image, and a tilt information detected by the tilt information detecting unit. An image processing apparatus comprising: an enlargement ratio variable control unit that variably controls the value of the set enlargement ratio for each pixel of the image read from the storage unit in accordance with the tilt information. 3. An image processing apparatus comprising: a storage unit for storing an input image; reading an image stored in the storage unit by an address control of the storage unit so that the image is enlarged to a set enlargement ratio; An image processing apparatus capable of generating an enlarged image by performing an interpolation process on the input image, including tilt information detecting means for detecting tilt information between pixels in the input image, wherein the tilt information detecting means An image processing apparatus for controlling an address value of the storage means used for the address control and an interpolation coefficient used for the interpolation processing according to the detected inclination information. 4. An image pickup means for picking up an image of a subject, generating and outputting a video signal of the picked up subject, a storage means for storing a video signal output from the image pickup means, and an image output from the image pickup means. Interpolating coefficient generating means for generating an interpolating coefficient used for an interpolating process for enlarging the video signal in accordance with the set enlarging ratio, wherein an interpolating coefficient between the pixels in the video signal generated by the imaging means A tilt information detecting unit for detecting tilt information, an output timing of the video signal from the imaging unit according to the tilt information detected by the tilt information detecting unit, and reading of the video signal from the storage unit. An image processing apparatus for controlling the correction of the address value of (i) and the interpolation coefficient generated by the interpolation coefficient generation means. 5. An image processing method for converting a low-resolution image into a high-resolution image corresponding to a set high-resolution ratio by interpolation processing, wherein the set high-resolution ratio and the low-resolution A step of generating an interpolation coefficient for calculating an interpolation pixel based on a distance between pixels in the image, a step of detecting inclination information between pixels in the low-resolution image, and the step of detecting the inclination information based on the detected inclination information. Correcting the interpolation coefficient, and performing an interpolation process on the low resolution image using the corrected interpolation coefficient, and outputting an image obtained by the interpolation process as the high resolution image. An image processing method characterized by the following. 6. An input image is stored in a storage means, and an image stored in the storage means is read out by an address control of the storage means so as to be enlarged to a set enlargement ratio, and the read image is read out. Detecting an inclination information between pixels in the input image, wherein the enlargement ratio is set according to the detected inclination information in an image processing method for generating an enlarged image by performing interpolation processing on the image. Variably controlling the value of each pixel of the image read from the storage means. 7. An input image is stored in a storage unit, and an image stored in the storage unit is read by an address control of the storage unit so as to be enlarged to a set enlargement ratio, and the read image is read. An image processing method for generating an enlarged image by performing an interpolation process on the input image, wherein the step of detecting tilt information between pixels in the input image is used for the address control according to the detected tilt information. An image processing method comprising controlling an address value of the storage means and an interpolation coefficient used for the interpolation processing. 8. An imaging means for imaging a subject, generating and outputting a video signal of the imaged subject, a storage means for storing a video signal output from the imaging means, and an image output from the imaging means. An interpolation coefficient generation unit for generating an interpolation coefficient used for interpolation processing for enlarging a video signal according to a set enlargement ratio, wherein the image signal is generated by the imaging unit. Detecting tilt information between pixels in the video signal; reading out the video signal from the storage means in accordance with the tilt information detected by the tilt information detecting means; Controlling the correction of the address value and the interpolation coefficient generated by the interpolation coefficient generation means. Method. 9. A storage medium storing a program for constructing, on an apparatus, an image processing system for converting a low-resolution image into a high-resolution image corresponding to a set high-resolution rate by interpolation processing. , The program
An interpolation coefficient generation module that generates an interpolation coefficient for calculating an interpolation pixel based on the set high-resolution rate and a distance between pixels in the low-resolution image; and an inclination between pixels in the low-resolution image. An inclination information detection module for detecting information, an interpolation coefficient correction module for correcting an interpolation coefficient generated by the interpolation coefficient generation module based on the inclination information detected by the inclination information detection module, and a correction by the interpolation coefficient correction module A interpolation module for performing interpolation processing on a low-resolution image using the interpolation coefficient thus obtained, and outputting an image obtained by the interpolation processing as the high-resolution image. 10. An apparatus having a storage unit for storing an input image, by reading an image stored in the storage unit by an address control of the storage unit so as to enlarge the image stored in the storage unit to a set magnification ratio. In a storage medium storing a program for constructing an image processing system capable of generating an enlarged image by performing an interpolation process on the input image, the program stores inclination information between pixels in the input image. A tilt information detection module to be detected, and a magnification ratio variable for variably controlling the value of the set magnification ratio for each pixel of the image read from the storage means according to the tilt information detected by the tilt information detection module. A storage medium characterized by including a control module. 11. An apparatus having storage means for storing an input image, by reading an image stored in said storage means by means of address control of said storage means so as to enlarge the image to a set enlargement ratio. In a storage medium storing a program for constructing an image processing system capable of generating an enlarged image by performing an interpolation process on the input image, the program stores inclination information between pixels in the input image. A tilt information detecting module to be detected, and a control module controlling an address value of the storage means used for the address control and an interpolation coefficient used for the interpolation process according to the tilt information detected by the tilt information detecting module. A storage medium comprising: 12. An image capturing means for capturing an image of a subject, generating and outputting a video signal of the captured subject, a storage means for storing a video signal output from the image capturing means, and an image output from the image capturing means. A storage medium storing a program executable on an image processing apparatus having an interpolation coefficient generation unit for generating an interpolation coefficient used for interpolation processing for enlarging a video signal according to a set enlargement ratio, A tilt information detection module for detecting tilt information between pixels in the video signal generated by the imaging unit, and a video signal of the video signal from the imaging unit according to the tilt information detected by the tilt information detection module. An output timing, an address value for reading out the video signal from the storage means, and an address value generated by the interpolation coefficient generation means. A control module for controlling the correction of the interpolation coefficient.