JP2009301224A - Image processing apparatus and image processing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a high quality image in which edges are enhanced when enlarging an input image. <P>SOLUTION: A navigation device produces edge enhanced image data by enhancing edges included in each input image data using an edge enhancing filter. Then, threefold enlarged image data is produced by enlarging an edge enhanced image using triplication which is a scaling factor of integral multiple which is larger than a previously set enlargement requested size (for example, a size of 800×480) and is the minimum size (for example, 960×540). Then, smoothed image data is produced by smoothing a threefold enlarged image using a smoothing filter, and output image data is produced by reducing the smoothed image data until becoming to be an enlargement requested size (for example, the size of 800×480). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an image processing apparatus and an image processing method.

  2. Description of the Related Art Conventionally, various techniques have been proposed for adjusting defects that occur in an image as the image is enlarged. For example, in Patent Document 1, the image is enlarged to an integral multiple and then reduced by an arbitrary multiple while securing a prescribed image enlargement ratio, thereby reducing oblique line jaggy (jaggedness) that occurs during image enlargement. Technology is disclosed.

  Similarly, in Patent Document 2, after enlarging an image by an arbitrary multiple, it is reduced by an integer multiple (pixel averaging), thereby ensuring a prescribed image enlargement ratio and ensuring the oblique lines generated during image enlargement. A technique for reducing jaggy (jaggedness) is disclosed.

  Japanese Patent Application Laid-Open No. 2004-228561 discloses a technique that uses blurring that occurs when an image is enlarged for an image blurring process and realizes an efficient blurring process together with a smoothing process when an image is reduced.

  Further, in Patent Document 4, an enlargement / reduction process in which an edge of an enlarged image is emphasized by setting an enlargement / reduction ratio of the image based on the sharpness of the outline of the image to be enlarged or reduced is described. Techniques that enable it are disclosed.

JP-A-9-37072 JP-A-11-161780 JP 2006-11539 A JP 2006-74155 A

  However, the above-described conventional technique has problems as described below. That is, the techniques disclosed in Patent Documents 1 to 3 described above have a problem in that no consideration is given to enhancing the edge of an enlarged image.

  In addition, the technique disclosed in Patent Document 4 described above sets the enlargement / reduction ratio of the image based on the sharpness of the outline of the image to be enlarged or reduced, so that an enlarged image with an emphasized edge can be obtained. There has been a problem that it cannot be obtained at the enlargement rate requested by the user.

  Accordingly, the present invention has been made to solve the above-described problems of the prior art, and image processing capable of obtaining a high-quality image with enhanced edges when performing an input image enlargement process. An object is to provide an apparatus and an image processing method.

  In order to solve the above-described problems and achieve the object, the present invention preliminarily sets an edge enhancement processing unit that emphasizes an edge included in an input image, and an input image in which the edge is enhanced by the edge enhancement processing unit. An image enlargement processing unit that enlarges the image to a predetermined size larger than the enlargement request size, a smoothing processing unit that smoothes the input image enlarged by the image enlargement processing unit, and a smoothing performed by the smoothing processing unit An image reduction processing unit that reduces the input image to the enlargement request size.

  Further, the present invention provides an edge enhancement processing step for enhancing edges included in an input image, and an input image whose edges are enhanced by the edge enhancement processing step to a predetermined size larger than a preset enlargement request size. An image enlarging process step for enlarging, a smoothing process step for smoothing the input image enlarged by the image enlarging process step, and an image for reducing the input image smoothed by the smoothing process step to the enlargement request size A reduction processing step.

  According to the present invention, when performing an enlargement process of an input image, it is possible to obtain a high-quality image with emphasized edges.

  Embodiments of an image processing apparatus and an image processing method according to the present invention will be described below in detail with reference to the accompanying drawings. In the following, a navigation apparatus to which an image processing apparatus according to the present invention is applied will be described as a first embodiment, and then another embodiment included in the present invention will be described.

  In the following first embodiment, the outline and features of the navigation device according to the first embodiment, the configuration and processing of the navigation device will be described in order, and finally the effects of the first embodiment will be described.

[Outline and Features of Navigation Device (Example 1)]
First, the outline and features of the navigation device according to the first embodiment will be described with reference to FIG. FIG. 1 is a diagram for explaining the outline and features of the navigation device according to the first embodiment.

  The navigation apparatus according to the first embodiment outlines that each of a plurality of frames of image data constituting video data received from a broadcasting station or the like is enlarged and output as video data to a disc play or a monitor.

  The navigation device according to the first embodiment is mainly characterized in that the input image data constituting the video data captured therein is emphasized and enlarged and then reduced to the required enlargement magnification.

  This main feature will be described in detail. As shown in FIG. 1, the navigation apparatus according to the first embodiment uses each of the input image data (for example, 320) constituting the video data captured inside using the edge enhancement filter. Edge-enhanced image data is generated by emphasizing the edges included in the size of × 180 (see (1) in FIG. 1).

  Next, the navigation device according to the first embodiment is an integral multiple that is larger than a preset enlargement request size (for example, 800 × 480) and has a minimum size (for example, 960 × 540). Three-times enlarged image data is generated by enlarging the edge-enhanced image using the magnification of three (see (2) in FIG. 1).

  Subsequently, the navigation device according to the first embodiment uses the smoothing filter to smooth the 3 times enlarged image to generate smoothed image data (see (3) in FIG. 1), and enlarges the smoothed image data. Output image data is generated by reducing the image size to a required size (for example, 800 × 480) (see (4) in FIG. 1).

  For this reason, the navigation device according to the first embodiment has the main characteristics described above, and thus can obtain a high-quality image in which edges are emphasized when the input image is enlarged. .

[Configuration of Navigation Device (Example 1)]
Next, the configuration of the navigation device according to the first embodiment will be described with reference to FIG. FIG. 2 is a block diagram illustrating the configuration of the navigation device according to the first embodiment.

  As shown in the figure, the navigation device 40 according to the first embodiment is connected to the display 20 and the speaker 30 via a bus 50. The display 20 outputs and displays video data received from the broadcast station 10, for example. For example, the speaker 30 outputs sound accompanying video data displayed on the display 20.

  As shown in FIG. 2, the navigation device 40 includes a decoder 10, a register 20, and an image processing unit 30.

  The decoder 10 receives video data broadcast from the broadcast station 10 and outputs it to the image processing unit 30. Note that the video data is configured by the YUV method (or Ycbcr method), and the luminance signal (Y), the difference between the luminance signal and the blue component (U or cb), and the difference between the luminance signal and the red component (V or cr). The following three pieces of information are included.

  The register 42 is a storage unit that stores data necessary for various types of processing by the image processing unit 43, and in particular, a filter coefficient 42a, an enlargement rate coefficient 43b, and a reduction rate used for processing in the image processing unit 43 described later. The coefficient 42c is stored.

  The image processing unit 43 is a processing unit that has a predetermined control program, a program that defines various processing procedures, and an internal memory for storing necessary data, and performs various processing using these, and in particular, an edge It has an enhancement processing unit 43a, an integer multiple enlargement processing unit 43b, a smoothing processing unit 43c, and an arbitrary magnification reduction processing unit 43d.

  The edge enhancement processing unit 43a uses an edge enhancement filter to enhance the edge included in each input image data (for example, 320 × 180 size) constituting the video data input from the decoder 41, thereby generating an edge enhanced image. The generated edge emphasis process is executed.

  Specifically, as shown in FIG. 3, the edge enhancement processing unit 43a reads the filter coefficient 42a from the register 42, sets weights (w1 to w9) for each component of the 3 × 3 tap filter, A sum Y of weights set for each component is calculated.

  Next, the edge enhancement processing unit 43a multiplies the pixel to be edge-processed and its surrounding pixels by the weight w, and calculates the sum X of the multiplication results.

  Subsequently, the edge enhancement processing unit 43a obtains an edge processing pixel by dividing the sum X by the sum Y. The edge enhancement processing unit 43a generates the edge enhanced image by executing the total X calculation process and the total X divided by the total Y for all the pixels of the input image data.

  Then, the edge enhancement processing unit 43a outputs the generated edge enhancement data to the integer multiple enlargement processing unit 43b.

  The integer multiple enlargement processing unit 43b enlarges each edge-enhanced image input from the edge enhancement processing unit 43a using an integer multiple that is larger than a preset enlargement request size and has a minimum size. As a result, an image enlargement process for generating enlarged image data is executed.

  Specifically, as shown in FIG. 4, the integer multiple enlargement processing unit 43b reads an enlargement factor coefficient 43b (for example, three times) from the register 42, and edge-enhanced image data (for example, a size of 320 × 180). By copying each pixel of, enlargement is performed at an integer multiple that is larger than a preset enlargement request size (for example, 800 × 480) and has a minimum size (for example, 960 × 540). The enlarged image data (for example, 3 times enlarged image data) is generated.

  Then, the integer multiple enlargement processing unit 43b outputs the generated enlarged image data to the smoothing processing unit 43c.

  The smoothing processing unit 43c smoothes each enlarged image data input from the integer multiple enlargement processing unit 43b using a smoothing filter, and executes a smoothing process for generating smoothed image data.

  Specifically, the smoothing processing unit 43c reads the filter coefficient 42a from the register 42, and uses the 3 × 3 tap filter in the same way as the edge enhancement processing unit 43a to perform the enlargement input from the integer multiple enlargement processing unit 43b. The image data is smoothed to generate smoothed image data.

  Then, the smoothing processing unit 43c outputs each generated smoothed image data to the arbitrary magnification reduction processing unit 43d.

  The arbitrary magnification reduction processing unit 43d performs image reduction processing for reducing each smoothed image data input from the smoothing processing unit 43c until the enlargement request size is reached, and generating output image data, respectively.

  Specifically, as shown in FIG. 5, the arbitrary magnification reduction processing unit 43d reads the reduction rate coefficient 43c from the register 42 and thins out pixels from the smoothed image data input from the smoothing processing unit 43c. The output image data is generated by reducing the size until it reaches the enlargement request size (for example, 800 × 480) (for example, reducing the size to 0.833 times in the horizontal direction and 0.889 times in the vertical direction).

  Then, the arbitrary magnification reduction processing unit 43d outputs video data reconstructed from the generated output image data to the display 20.

[Navigation Device Processing (Example 1)]
Subsequently, processing of the navigation device according to the first embodiment will be described with reference to FIGS. 6 and 7. FIG. 6 is a diagram illustrating a process flow of the navigation device according to the first embodiment. FIG. 7 is a diagram illustrating an outline of processing of the navigation device according to the first embodiment.

  As shown in the figure, the edge enhancement processing unit 43a uses the edge enhancement filter to enhance edges included in each input image data (for example, 320 × 180 size) constituting the video data input from the decoder 41. Then, edge enhancement processing for generating edge-enhanced images is executed (see step S601, (1) in FIG. 7).

  Specifically, the edge enhancement processing unit 43a reads the filter coefficient 42a from the register 42, sets weights (w1 to w9) for each component of the 3 × 3 tap filter (see FIG. 3), and each component. The sum Y of weights set for each is calculated.

  Next, the edge enhancement processing unit 43a multiplies the pixel to be edge-processed and its surrounding pixels by the weight w, and calculates the sum X of the multiplication results.

  Subsequently, the edge enhancement processing unit 43a obtains an edge processing pixel by dividing the sum X by the sum Y. The edge enhancement processing unit 43a generates the edge enhanced image by executing the total X calculation process and the total X divided by the total Y for all the pixels of the input image data.

  Then, the edge enhancement processing unit 43a outputs the generated edge enhancement data to the integer multiple enlargement processing unit 43b.

  The integer multiple enlargement processing unit 43b enlarges each edge-enhanced image input from the edge enhancement processing unit 43a using an integer multiple that is larger than a preset enlargement request size and has a minimum size. Thus, an image enlargement process for generating enlarged image data is executed (see step S602, (2) in FIG. 7).

  Specifically, the integer multiple enlargement processing unit 43b reads the enlargement factor coefficient 43b (for example, 3 times) from the register 42, and copies each pixel of the edge enhanced image data (for example, the size of 320 × 180). (See FIG. 4), the image is enlarged at a magnification that is larger than a preset enlargement request size (for example, 800 × 480) and an integral multiple that is the minimum size (for example, 960 × 540). Enlarged image data (for example, 3 times enlarged image data) is generated.

  Then, the integer multiple enlargement processing unit 43b outputs the generated enlarged image data to the smoothing processing unit 43c.

  The smoothing processing unit 43c smoothes each enlarged image data input from the integer multiple enlargement processing unit 43b using a smoothing filter, and executes a smoothing process for generating each of the smoothed image data (step S603, (See (3) in FIG. 7).

  Specifically, the smoothing processing unit 43c reads the filter coefficient 42a from the register 42, and uses the 3 × 3 tap filter in the same way as the edge enhancement processing unit 43a to perform the enlargement input from the integer multiple enlargement processing unit 43b. The image data is smoothed to generate smoothed image data.

  Then, the smoothing processing unit 43c outputs each generated smoothed image data to the arbitrary magnification reduction processing unit 43d.

  The arbitrary magnification reduction processing unit 43d performs image reduction processing for reducing the respective smoothed image data input from the smoothing processing unit 43c until the enlargement request size is reached, and generating output image data (step S604, FIG. 7 (4)).

  Specifically, as shown in FIG. 5, the arbitrary magnification reduction processing unit 43d reads the reduction rate coefficient 43c from the register 42 and thins out pixels from the smoothed image data input from the smoothing processing unit 43c. Output image data is generated by reducing the image size to the enlargement request size (for example, 800 × 480).

  Then, the arbitrary magnification reduction processing unit 43d outputs video data reconstructed from the generated output image data to the display 20 (step S605).

[Effects of Example 1]
As described above, according to the first embodiment, it is possible to obtain a high-quality image in which edges are emphasized when an input image is enlarged.

  Further, according to the first embodiment, the edge enhancement process for enhancing the edges included in the input image data is executed. Therefore, the edge information included in the enlarged image is maintained at a constant amount, and the entire image is blurred. Can be reduced.

  In addition, according to the first embodiment, since the pixel is enlarged without being processed by interpolation (resampling) by pixel copying of the edge-enhanced image, the edge information included in the pixel can be utilized as much as possible without being destroyed. In addition, the scale of the arithmetic circuit for performing numerical calculations can be reduced as compared with the case of performing the enlargement process with the real number magnification.

  Moreover, according to Example 1, since the enlarged image produced | generated by the enlargement process is smoothed, the jaggy generated in the enlarged image by the enlargement process can be reduced.

  Further, according to the first embodiment, the enlargement process is performed at an integer multiple that is larger than the enlargement request size (for example, 800 × 480) and the minimum size (for example, 960 × 540). The smoothed enlarged image can be reduced with high precision at a magnification close to 1.

  Further, according to the first embodiment, the enlarged image that has been smoothed can be accurately reduced at a magnification close to 1, so that the entire image can be tightened and blurring of the entire image generated by the smoothing processing can be achieved. Can be improved.

  Although the embodiments of the present invention have been described so far, the present invention may be implemented in various different forms other than the embodiments described above. Therefore, another embodiment included in the present invention will be described below.

(1) Device Configuration Each component of the navigation device 40 shown in FIG. 2 is functionally conceptual and does not necessarily need to be physically configured as shown. That is, the specific form of distribution / integration of the navigation device 40 is not limited to that shown in the figure. For example, all or a part of the edge enhancement processing unit 43a and the integral multiple enlargement processing unit 43b may be integrated. Depending on the load, usage conditions, etc., any unit can be functionally or physically distributed and integrated.

  Further, each processing function (for example, see FIG. 6 and the like) performed by the navigation device 40 is realized by a CPU and a program that is analyzed and executed by the CPU, or wired. It can be realized as hardware by logic.

(2) Image processing program In addition, in the various processes of the apparatus described in the first embodiment (for example, see FIG. 6 and the like), a program prepared in advance is executed by a computer system such as a personal computer or a workstation. Can be realized. In the following, an example of a computer that executes an image processing program having the same function as that of the first embodiment will be described with reference to FIG. FIG. 8 is a diagram illustrating a computer that executes an image processing program.

  As shown in the figure, a computer 60 as a navigation device is configured by connecting an input unit 61, an output unit 62, an HDD 63, a RAM 64 and a CPU 65 via a bus 70.

  Here, the input unit 61 receives input of various data from the user. The output unit 62 displays various information. The HDD 63 stores information necessary for executing various processes by the CPU 65. The RAM 64 temporarily stores various information. The CPU 65 executes various arithmetic processes.

  As shown in FIG. 8, the HDD 63 stores in advance an image processing program 63a that performs the same function as each processing unit of the apparatus shown in the first embodiment and image processing data 63b. Yes. Note that the image processing program 63a can be appropriately distributed and stored in a storage unit of another computer that is communicably connected via a network.

  Then, the CPU 65 reads out the image processing program 63a from the HDD 63 and develops it in the RAM 64, whereby the image processing program 63a functions as an image processing process 64a as shown in FIG. Then, the image processing process 64a reads the image processing data 63b and the like from the HDD 63, expands them in an area allocated to itself in the RAM 64, and executes various processes based on the expanded data and the like. The image processing process 64a is performed in the image processing unit 43 (edge enhancement processing unit 43a, integer multiple enlargement processing unit 43b, smoothing processing unit 43c, and arbitrary magnification reduction processing unit 43d) of the navigation device 40 shown in FIG. Each corresponds to the process to be executed.

  The above-described image processing program 63a is not necessarily stored in the HDD 63 from the beginning. For example, a flexible disk (FD), a CD-ROM, a DVD disk, a magneto-optical disk, an IC inserted into the computer 60, for example. Each program is stored in a “portable physical medium” such as a card, or “another computer (or server)” connected to the computer 60 via a public line, the Internet, a LAN, a WAN, or the like. The computer 60 may read out and execute each program from these.

(3) Image processing method The following image processing method is implement | achieved by the navigation apparatus 40 demonstrated in said Example 1. FIG.

  That is, an edge emphasis processing step for emphasizing an edge included in the input image (see, for example, step S601 in FIG. 6), and an input image in which the edge is emphasized by the edge enhancement processing step An image enlargement processing step that enlarges until an image that matches a large predetermined size (see, for example, step S602), and an input image that has been enlarged by the image enlargement processing step until an image that matches the predetermined size is smoothed. A smoothing processing step (for example, see step S603), an image reduction processing step for reducing the input image smoothed by the smoothing processing step until the image matches the enlargement request size (for example, see step S604), An image processing method including the above is realized.

  As described above, according to the image processing apparatus and the image processing method of the present invention, the image data of a plurality of frames constituting video data received from a broadcasting station or the like is enlarged and processed as video data on a disc play or a monitor. This is useful for output, and is particularly suitable for obtaining a high-quality image with emphasized edges when an input image is enlarged.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure for demonstrating the outline | summary and characteristic of the navigation apparatus which concern on Example 1. FIG. 1 is a block diagram illustrating a configuration of a navigation device according to Embodiment 1. FIG. It is a figure for demonstrating the edge emphasis process which concerns on Example 1. FIG. FIG. 6 is a diagram for explaining image enlargement processing according to the first embodiment. FIG. 6 is a diagram for explaining image reduction processing according to the first embodiment. It is a figure which shows the flow of a process of the navigation apparatus which concerns on Example 1. FIG. It is a figure which shows the outline | summary of the process of the navigation apparatus which concerns on Example 1. FIG. It is a figure which shows the computer which executes an image processing program.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Broadcasting station 20 Display 30 Speaker 40 Navigation apparatus 41 Decoder 42 Register 42a Filter coefficient 42b Expansion rate coefficient 42c Reduction rate coefficient 50 Bus 60 Computer (navigation apparatus)
61 Input Unit 62 Output Unit 63 HDD (Hard Disk Drive)
63a Image processing program 63b Image processing data 64 RAM (Random Access Memory)
64a Image processing process 65 CPU (Central Processing Unit)
70 bus

Claims (3)

An edge enhancement processing unit for enhancing edges contained in the input image;
An image enlargement processing unit for enlarging the input image whose edges are enhanced by the edge enhancement processing unit to a predetermined size larger than a preset enlargement request size;
A smoothing processor that smoothes the input image enlarged by the image enlargement processor;
An image reduction processing unit that reduces the input image smoothed by the smoothing processing unit to the enlargement request size;
An image processing apparatus comprising:   The image enlargement processing unit enlarges the input image whose edges are emphasized by the edge enhancement processing unit using a magnification that is an integral multiple that is larger than the enlargement request size and has a minimum size. The image processing apparatus according to claim 1. An edge enhancement processing step for enhancing edges contained in the input image;
An image enlargement process step of enlarging the input image with the edge enhanced by the edge enhancement process step to a predetermined size larger than a preset enlargement request size;
A smoothing processing step for smoothing the input image enlarged by the image enlargement processing step;
An image reduction processing step for reducing the input image smoothed by the smoothing processing step to the enlargement request size;
An image processing method comprising:

Images