KR20020054215A - The Apparatus and Method for Image Fusion using Multisensor Data - Google Patents

Abstract

PURPOSE: A device for synthesizing images using multi satellite images is provided to use saturation when synthesizing more than two satellite images to make new images, thereby maintaining maximum information and implementing high-density image synthesis. CONSTITUTION: A receiver(210) receives images of a Landsat TM satellite. A band selector/combiner(220) selects bands of the received satellite image, and combines the bands. An HIS(Hue Intensity Saturation) converter(230) performs an HIS conversion with band units combined by the band selector/combiner. A 3S component extractor(240) extracts 3S components of an HIS-converted image of the HIS converter. An image synthesizer(250) synthesizes the extracted 3S components with an image of a high-resolution satellite.

Description

Image Synthesis Device Using Multi-Satellite Image and Its Method {The Apparatus and Method for Image Fusion using Multisensor Data}

The present invention relates to an image synthesizing technique using multi-satellite images. More particularly, in synthesizing two or more satellite images to create a new image, an image synthesizing apparatus using a saturation element, a method thereof, and the method The present invention relates to a computer-readable recording medium having recorded thereon a program for realizing this.

Earth observation satellites can be broadly classified into satellites launched for scientific purposes, such as AVHRR and Landsat ™, and satellites for commercial purposes, such as SPOT, IRS and IKONOS. In addition, according to the wavelength band that the satellite uses to observe the earth, it can be classified into optical images such as LandsatTM, SPOT, IRS, IKONOS, and radar images such as RADARSAT, ERS-1, and Seasat.

These satellites generally have different spatial resolutions, observation periods, spectral resolutions, and wavelength bands, depending on the purpose of launching the satellite and what the primary object of the satellite is being observed. Each image has unique features.

Therefore, by synthesizing various types of images, different information that cannot be obtained from one image can be obtained together.

In general, the purpose of synthesizing images is to greatly increase the spatial resolution of the image to make it easier to analyze, to see certain features or phenomena that are not visible in one image, to improve the accuracy of image classification, It can be divided into detecting changes using multi-time images, and correcting information not displayed by cloud or shadow effects when the surface is taken by one sensor.

In addition, the synthesis of satellite images can be classified into the following two types according to the images used. A synthesis method in which an optical image such as Landsat TM and a radar image such as RADARSAT are synthesized to take advantage of the two data. It is a type that synthesizes panchromatic images with low spatial resolution but low spectral resolution such as IRS and SPOT and low spatial resolution like Landsat TM.

FIG. 1 is a flowchart illustrating a conventional method of synthesizing HIS (HIS: Huis Intensity Saturation) image.

The HIS synthesis method is the most commonly used synthesis method since it was first used by Hyden in 1982.

The HIS method was used in 1990 to synthesize multispectral images of the same satellite as SPOT panchromatic images, and in 1991 to synthesize SPOT panchromatic images and Landsat ™ images.

In 1993, aerial photographs and Landsat TM images were shown to be useful for terrain analysis when synthesized using the HIS synthesis method. In 1994, SPOT multispectral images and HIS synthesis methods were used. A numerical elevation model (DEM) was synthesized to create a color numerical elevation model.

In 1998, when Landsat TM images and SPOT panchromatic images were synthesized by HIS synthesis method, it was not possible to classify images using only one image. It has been shown to improve classification accuracy.

In the general HIS synthesis method, as shown in FIG. 1, a Landsat TM satellite image is input (110), and a black and white image such as panchromatic is input to the received image to perform HIS conversion (120). In step 140, image intensity is corrected by generating an intensity image having a corrected spectral resolution and performing HIS inverse transformation on the generated image (140).

Until now, a number of methods for synthesizing high-resolution panchromatic images and low-resolution multispectral images have been developed.However, in this study, HIS synthesis method, PCA (Principal Component Analysis) synthesis, which is widely used The method and wavelet synthesis method, which has been studied a lot recently, were selected.

In the HIS synthesis method, an intensity image, a hue image, and a saturation image are generated by applying an HIS transform to three low resolution images present in an RGB color model. Due to this conversion, the contrast image contains information related to the spatial resolution, and the hue image and saturation image contain information related to the spectral resolution, so that the contrast image of the high resolution black and white image is replaced with that of the low resolution.

Finally, RGB conversion is performed using the contrast image, the hue image, and the saturation image of the black and white image.

In the PCA synthesis method, a low resolution image to be synthesized is converted into a principal component image through PCA analysis.

At this time, since the first main component includes the spatial resolution of the low resolution image, the first main component is exchanged for a black and white image, and the inverse PCA transform is performed using the black and white images and the remaining main component images except the first main component.

In the wavelet synthesis method, when a wavelet transform is performed on an image, one approximation image and three detail images are obtained.

In this case, the schematic image includes information related to the spectral resolution of the image, and the precise image includes the sympathetic resolution according to the orientation. Therefore, in the wavelet synthesis method, after applying the wavelet transform, the low resolution image is replaced with the high resolution image, and then the inverse wavelet transform is performed using the low resolution image and the high resolution image.

However, in the method of maintaining the information of the two images as much as possible by combining the spatial information of the high resolution image and the spectral information of the low resolution image from two or more satellite images as described above, the ultra-high resolution satellite image (spatial resolution) 5m or less) has appeared since 1999, and in the conventional HIS transformation, when the ratio of the spatial resolution of two images exceeds 1:10, image blurring occurs on the result of the synthesized image. There is a problem that appears.

The present invention proposed to solve the above problems, in synthesizing two or more satellite images to create a new image, an image synthesizing apparatus using a saturation element and its method and to realize the method Its purpose is to provide a computer readable recording medium having recorded thereon a program.

1 is a flowchart illustrating an exemplary HIS image synthesis method.

2A and 2B illustrate an embodiment of an apparatus and method for synthesizing images using 3S transform according to the present invention.

3A and 3B are exemplary views for comparing and explaining images before and after image synthesis according to the present invention.

* Explanation of symbols for the main parts of the drawings

210: receiver 220: band selector / combiner

230: HIS conversion unit 240: 3S component extraction unit

250: 3S converter 260: video synthesizer

An apparatus of the present invention for achieving the above object is an image synthesizing apparatus using a multi-satellite image, comprising: receiving means for receiving image data from a plurality of satellites; Band selection / combining means for selecting and combining the bands of the image data of the first satellite received by the receiving means; HIS conversion means for performing HIS conversion for each band selected and combined by the band selection / combining means; Component extracting means for extracting respective chroma components for each combination of bands converted by the HIS converting means; And image synthesizing means for synthesizing the image data of the second satellite with the chroma components extracted by the component extraction means.

In addition, the method of the present invention comprises the steps of: receiving an image of a satellite and configuring a band combination of the received image data; Performing a HIS conversion of the received image data and extracting each chroma component for each combination of the configured bands; And a third step of synthesizing image data received from another satellite to the extracted chroma component.

The present invention also provides a video synthesizing system having a processor, comprising: a first function of receiving a satellite image and configuring a band combination of the received image data; Performing a HIS conversion of the received image data and extracting respective chroma components for each combination of the configured bands; And a computer-readable recording medium having recorded thereon a program for realizing a third function of synthesizing image data received from another satellite in the extracted chroma components.

The above objects, features and advantages will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2A and 2B are exemplary diagrams illustrating an apparatus and method for synthesizing images using 3S transform according to the present invention.

First, as shown in FIG. 2A, the image synthesizing apparatus by 3S conversion according to the present invention includes a receiver 210 for receiving an image of a Landsat TM satellite and a band of the satellite image received by the receiver 210. Band selection / combining unit 220 for selecting and combining, HIS conversion unit 230 for performing HIS conversion in units of bands combined by the band selection / combining unit 220, and HIS in the HIS conversion unit 230 The 3S component extractor 240 extracts the 3S component of the converted image, and the image synthesizer 250 synthesizes the high resolution satellite image to the 3S component extracted by the 3S component extractor 240.

In addition, in the method of image synthesis by 3S transformation according to the present invention, as shown in FIG. 2B, a saturation component is synthesized with a high-resolution image by OIF (OIF). An image of a TM satellite is received (262), bands are combined by an OIF such as data mining (263), and HIS transformation is performed for each of the combined bands (264).

Thus, each saturation (S) component is extracted for each HIS-converted band (265), and a high-resolution satellite image is input (261) to generate a synthesized image (266).

Using the 3S component (277), the <mathematical formula> applied in generating a composite image (278) is as follows.

Where,

3A and 3B are exemplary views for comparing and explaining images before and after image synthesis according to the present invention. That is, FIG. 3A shows images captured by individual satellites, and FIG. 3B shows synthesized images.

In addition, the image shown at the top of Figure 3b is a 3S composite image according to the present invention, the image shown at the bottom is a conventional HIS composite image. As can be seen in Figures 3a and 3b, it can be seen that the image quality of the 3S composite image according to the present invention is the best.

As described above, the method of the present invention may be implemented in a program and stored in a recording medium (CD-ROM, RAM, ROM, floppy disk, hard disk, magneto-optical disk, etc.) in a computer-readable form.

The present invention described above is capable of various substitutions, modifications, and changes without departing from the spirit of the present invention for those skilled in the art to which the present invention pertains, and the above-described embodiments and accompanying It is not limited to the drawing.

As described above, the present invention improves the conventional HIS conversion method, maintains the information amount of Landsat TM as much as possible, efficiently synthesizes high-precision images, and prevents blurring even in image synthesis with high-quality satellite images. It can work.

Claims (6)

An image synthesizing apparatus using multi-satellite images, Receiving means for receiving image data from a plurality of satellites; Band selection / combining means for selecting and combining the bands of the image data of the first satellite received by the receiving means; HIS conversion means for performing HIS (HIS: Hue Intensity Saturation) conversion for each band selected and combined by the band selection / combination means; Component extracting means for extracting respective chroma components for each combination of bands converted by the HIS converting means; And Image synthesizing means for synthesizing the image data of the second satellite with the chroma components extracted by the component extracting means Image synthesizing apparatus comprising a. The method of claim 1, The component extraction means, And an OV (Optimum Index Factor) method for extracting each saturation component for each combination of bands of the image data. The method of claim 1, The second satellite, A satellite for providing a high resolution image, comprising: DD-5 and IRS-1C. An image synthesizing method applied to an image synthesizing apparatus using a multi-satellite image, Receiving a satellite image and constructing a band combination of the received image data; Performing a HIS conversion of the received image data and extracting each chroma component for each combination of the configured bands; And A third step of synthesizing image data received from another satellite to the extracted chroma components Image synthesis method comprising a. The method of claim 4, wherein The second step, And an OIF method for extracting respective chroma components for each combination of bands of the image data. In an image synthesis system with a processor, A first function of receiving an image of a satellite and configuring a band combination of the received image data; A second function of performing respective HIS transformation of the received image data to extract respective chroma components for each combination of the configured bands; And A third function of synthesizing image data received from another satellite to the extracted chroma components A computer-readable recording medium having recorded thereon a program for realizing this.