CN1949821A - Method for recovering image with removal of noise in frequency image data and apparatus thereof - Google Patents
Method for recovering image with removal of noise in frequency image data and apparatus thereof Download PDFInfo
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Abstract
The invention relates to a method for recovering image with removal of noise in frequency image information and apparatus thereof. In this invention, freuency information of associated image expert group acting as image information on a freuency domain is lowpass filtered so as to effectively remove noise in the frequency image information. Thus, the apparatus for recovering image with removal of noise in the image information is used for recovering the frequency image information which is compressed when space image information on a space domain is transformed to information on a freuency domain. The apparatus of the invention comprises following parts: a lowpass filter unit for lowpass filtering the frequency image information in order to remove noise in the frequency image information; and an inverse transforming unit for transforming the lowpass filtered frequency image information to the space image information and recovering the information.
Description
Technical field
The present invention relates to remove in the frequency image information image restoration method and the device thereof of noise, particularly relate to and a kind of JPEG frequency information as the image information on the frequency domain is carried out low-pass filtering operation, make image restoration method and the device thereof of removing noise in the frequency image information that in the frequency image information, effectively to remove noise.
Along with the compelling development of digitized video technology, the current several different methods that can effectively compress and restore digital image information of developing.Particularly after taking photograph, pass through the compact display apparatus of installation, for example by small-sized liquid crystal indicator (liquid crystal display, LCD) etc. the mobile communication terminal that can directly appreciate the digital camera of the photograph of taking and be provided with digital camera is widely used, thereby need effectively the compressed digital image information more so that in finite storage space the more photograph of storage, and the algorithm (algorithm) that the photograph of compression is shown with the image quality that is close to master by compact display apparatus.
JPEG (joint photographic coding experts group-joint image expert group) mode also is one of them, and its use will be converted to frequency image information on the frequency domain and the technology of compressing by DCT (discrete cosine transform-discrete cosine transform) as the space image information of the data on the spatial domain.
But, when under the lower environmental condition of illumination, utilizing the digital camera of digital camera or mobile communication terminal to take photograph, shown in Fig. 5 a, will comprise more noise in the space image information of taking and obtaining by camera.And, after compressing by the JPEG mode and store, the space image information that will shoot again it is restored under the situation about playing, the camera of digital camera or mobile communication terminal will be carried out extraction (decimation) operation of the corresponding space image information being carried out reduced sampling (downsampling) for show image information in compact display apparatus.Along with carrying out above-mentioned extraction operation, the noise that comprises in the image information of space will be more outstanding shown in Fig. 5 b.
Summary of the invention
Technical problem to be solved by this invention is to provide image restoration method and the device thereof of removing noise in a kind of frequency image information, when restoring the image information that compresses by JPEG (joint photographic coding expertsgroup-joint image expert group) mode, remove the noise that comprises in the image information efficiently and effectively with making.
For achieving the above object, remove the image restoration device of noise in the image information of the present invention, it is used for the space image information on the spatial domain is converted to the information on the frequency domain and the frequency image information that compresses restores, the present invention is characterized in that, includes following several sections: the low pass filter portion that the said frequencies image information is carried out low-pass filtering operation in order to remove noise from the said frequencies image information; The inverse conversion portion that above-mentioned low pass filtered wave frequency image information is converted to above-mentioned space image information and restores.
And the present invention is characterized in that, also includes: the entropy lsb decoder of the said frequencies image information being carried out entropy decoding (entropy decoding) operation; The frequency image information of above-mentioned decoding is carried out the re-quantization portion that above-mentioned low pass filter portion was operated and exported to re-quantization (de-quantization).
And, the present invention is characterized in that: the said frequencies image information is the JPEG frequency information that compresses by JPEG (jointphotographic coding experts group-joint image expert group) mode, above-mentioned space image information is the JPEG spatial information that restores by the JEPG mode, above-mentioned inverse conversion portion carries out IDCT (inverse discrete cosinetransform-inverse discrete cosine transform) operation and restores above-mentioned JPEG spatial information above-mentioned low pass filtered wave frequency image information, and also includes above-mentioned JEPG spatial information is carried out the color conversion operation and generated the color converting of RGB (red green blue) space image information.
And the present invention is characterized in that, also includes: the display part that is used to show above-mentioned rgb space information; In order to be suitable for above-mentioned display part above-mentioned rgb space information is extracted the output processing part that (decimation) operates and show.
And, for achieving the above object, remove the image restoration method of noise in the frequency image information of the present invention, the image restoration method that the frequency image information that will compress as being converted to the information on the frequency domain to the space image information on the spatial domain restores, the present invention is characterized in that, includes following several steps: the low-pass filtering step of the said frequencies image information being carried out low-pass filtering operation in order to remove the noise in the said frequencies image information; The inverse conversion step that above-mentioned low pass filtered wave frequency image information is converted to above-mentioned space image information and restores.
And the present invention is characterized in that, also includes: the entropy decoding step of the said frequencies image information being carried out entropy decoding (entropy decoding) operation; Image information to above-mentioned decoding is carried out the re-quantization step that above-mentioned low-pass filtering step was operated and moved to re-quantization (de-quantization).
And, the present invention is characterized in that: the said frequencies image information is the JPEG frequency information that compresses by JPEG (jointphotographic coding experts group-joint image expert group) mode, above-mentioned space image information is the JPEG spatial information that restores by the JEPG mode, in above-mentioned inverse conversion step, above-mentioned low pass filtered wave frequency image information is carried out IDCT (inverse discretecosine transform-inverse discrete cosine transform) operation and restored above-mentioned JPEG spatial information, and also include the color conversion step that above-mentioned JEPG spatial information execution color conversion operation is generated RGB (red green blue) space image information.
And the present invention is characterized in that, also includes: at the rgb space information of restoring by above-mentioned inverse conversion step, to carry out and extract the output treatment step that (decimation) operates and show in order to be suitable for showing.
Adopt the present invention, JPEG portion carried out low-pass filtering operation to the JPEG frequency information before carrying out extraction operation, comprise noise in the JPEG frequency information hardly thereby make.Thus, when carrying out extraction operation, need not rgb space information is carried out filtering operation in addition.
And, according to aforesaid the present invention, can remove the noise that comprises in the JPEG frequency information by software mode, making need not additional expenses and power consumption and the image information that compresses by the JPEG mode of real time restoration easily.
Description of drawings
Fig. 1 is a block diagram of removing the image restoration device of noise in the frequency image information of one embodiment of the invention;
Fig. 2 is the more detailed block diagram of the image part that illustrates among Fig. 1 of one embodiment of the invention;
Fig. 3 is the concept map of the JPEG frequency information of one embodiment of the invention;
Fig. 4 is a flow chart of removing the image restoration method of noise in the frequency image information of one embodiment of the invention;
Fig. 5 a to Fig. 5 d is used to illustrate that the noise of the image restoration device of one embodiment of the invention removes the picture view of effect.
Wherein, Reference numeral:
100: image restoration device 110: input part
120: display part 130: image part
131: camera 132:JPEG portion
133: Hofmann decoding portion 134: re-quantization portion
135: 136:IDCT portion of low pass filter portion
137: color converting 138: output processing part
140: storage part 150: control part
Embodiment
With reference to the accompanying drawings the preferred embodiment among the present invention is described in detail.
Fig. 1 is a block diagram of removing the image restoration device of noise in the frequency image information of one embodiment of the invention.
1 describe with reference to the accompanying drawings, include input part 110, display part 120, image part 130, storage part 140 and control part 150 in the image restoration device 100 of one embodiment of the invention.
Wherein, be provided with text button, numerical key and various function key in the above-mentioned input part 110, it is used to generate the key data corresponding with the key of user's input and output it to above-mentioned control part 150.
Above-mentioned display part 120 is liquid crystal indicator display unit such as (LCD), and its Presentation Function control signal according to above-mentioned control part 150 shows various images or lteral data.Particularly, above-mentioned display part 120 is used to show the rgb space information of restoring by above-mentioned image part 130.
After the relevant light signal of 3 dimension shapes that above-mentioned image part 130 will be imported is converted to RGB (the red green blue) spatial information of pixel of the brightness that has on 2 dimensional planes and color value, above-mentioned rgb space information translation for to be compressed into the JPEG frequency information of frequency-domain information by JPEG (joint photographic coding experts group-joint image expert group) mode, is included camera 131, JPEG portion 132 and output processing part 138 in the above-mentioned image part 130.
Wherein, when the user pressed the keypad of above-mentioned input part 110 and start above-mentioned camera 131, the light signals of the image that the 3 dimension shapes that above-mentioned camera 131 enters the camera lens by above-mentioned camera 131 in the certain hour are relevant were converted to having the above-mentioned rgb space information of different redness, green and blue brightness and color value and exporting to above-mentioned JPEG portion 132 by each pixel on 2 dimensional planes.
Above-mentioned JPEG portion 132 compresses above-mentioned rgb space information by above-mentioned JPEG mode, it is stored in the above-mentioned storage part 140 after generating the JPEG frequency information corresponding with above-mentioned rgb space information.Wherein, above-mentioned JPEG frequency information refers to above-mentioned rgb space information is compressed the image information that generates by the JPEG mode, and it is to be information on the frequency domain and the frequency image information that compresses with the above-mentioned rgb space information translation on the spatial domain.
And, after above-mentioned JEPG portion 132 carries out low-pass filtering and removes noise according to user's selection and to the above-mentioned JPEG frequency information of storage in the above-mentioned storage part 140, the JPEG frequency information recovery of above-mentioned execution low-pass filtering is above-mentioned rgb space information, and it is presented in the above-mentioned display part 120 by above-mentioned output processing part 138.
Because the above-mentioned JPEG frequency information as the information on the frequency domain is carried out low-pass filtering operation, make with to the information and executing filtering operation on the spatial domain relatively the time its operand less, thereby can remove operation to carrying out noise more rapidly easily as the above-mentioned JPEG frequency information of image information.
And above-mentioned JPEG portion 132 can pass through the software mode time, therefore need not to use the hardware chip that needs additional expenses and power, and can remove noise easily from the JPEG frequency information.
Rgb space information and executing to above-mentioned recovery extracts (decimation) operation to above-mentioned output processing part 138 in order to be suitable for showing in the above-mentioned display part 120, will carry out the rgb space information of above-mentioned extraction operation subsequently and export to above-mentioned display part 120.
Above-mentioned display part 120 by compact display apparatus for example liquid crystal indicator (LCD) constitute, in above-mentioned liquid crystal indicator under the situation of show image information, use had the QCIF form of 172 * 220 size etc.For above-mentioned rgb space information is presented at above-mentioned liquid crystal indicator with above-mentioned QCIF (quarter common intermediateformat-1/4th CLV Common Intermediate Formats) form, need to carry out only extraction (decimation) operation of sampling (sampling) one part of pixel from above-mentioned rgb space information.
But, when together carrying out filtering operation, will cause operand to increase and processor etc. will be produced overload, simultaneously playing video in real time by above-mentioned filter and above-mentioned extraction operation.And, under the situation that realizes above-mentioned filter by hardware mode, will need additional expenses and power consumption.
Under the situation of above-mentioned image restoration device 100,, make to need not together to carry out the sharp image that filtering operation also can be play the intimate master of removing noise shown in Fig. 5 d with above-mentioned extraction operation owing to above-mentioned JPEG frequency information is carried out low-pass filtering operation.
Above-mentioned JPEG portion 132 carried out low-pass filtering operation to above-mentioned JPEG frequency information before carrying out above-mentioned extraction operation, comprise noise hardly thereby make in the above-mentioned rgb space information.
Above-mentioned storage part 140 is subjected to the control of above-mentioned control part 150, it stores operation program, the system program that needs in the control operation of above-mentioned control part 150, and includes the random-access memory (RAM) of the data that are used for a plurality of operation programs execution of interim storage generation.Particularly, in the above-mentioned storage part 140 storage as the JPEG frequency information of the image information that above-mentioned rgb space information is compressed by the JPEG mode and generate.
Above-mentioned control part 150 is used to control the molar behavior of above-mentioned image restoration device 100, particularly controls above-mentioned image part 130 according to user's key input operation and moves.
To constitute under the situation of above-mentioned image part 130 by DB 2020 chips (digital baseband 2020 chip-digital basebands 2020 chips), above-mentioned JPEG portion 132 can realize that above-mentioned output processing part 138 can pass through PDI_CON (the display module interface-display module interface) realization of XGAM module (graphicaccelerator module-image accelerating module) by the arm processor in above-mentioned DB 2020 chips.
Fig. 2 is the more detailed block diagram of the image part that illustrates among Fig. 1 of one embodiment of the invention.
2 describe with reference to the accompanying drawings, include in the JPEG portion 132 of the image restoration device 100 of one embodiment of the invention: Hofmann decoding portion (huffman decoding part) 133, re-quantization portion (de-quantizing part) 134, low pass filter portion 135, (inverse discretecosine transform part-inverse discrete cosine transform portion) 136 of IDCT portion and color converting (colorconversion part) 137.
Wherein, 133 pairs of JPEG frequency informations of above-mentioned Hofmann decoding portion are carried out the Hofmann decoding operation and are generated the JPEG frequency information of decoding.
Above-mentioned JPEG frequency information obtains compression by the huffman coding method, and above-mentioned Hofmann decoding portion 133 will utilize the huffman code tables (huffman code table) that comprises in the above-mentioned JPEG frequency information that above-mentioned JPEG frequency information is decoded.
Above-mentioned huffman coding method is obtain the frequency number of each information in the arrangement of each information after, utilize above-mentioned frequency number to obtain the length of above-mentioned code and utilize the length of respective code to obtain the method for Hoffman code, it is a kind of of entropy coding mode (entropy encoding).Wherein, above-mentioned entropy coding mode is a kind of of harmless (loseless) coded system, and it is the mode of the symbolic representation information of using suitable length according to the statistical generation frequency of information or continuous information.The relevant content of above-mentioned Hofmann decoding action belongs to technique known, so will save detailed description thereof at this.Except above-mentioned Huffman mode, also can use other entropy coding mode, for example can adopt arithmetic, decoding (arithmetic/decoding) mode.
The JPEG frequency information of 134 pairs of above-mentioned decodings of above-mentioned re-quantization portion is carried out the re-quantization operation and is generated the JPEG frequency information of re-quantization, and above-mentioned JPEG frequency information is to quantize and information compressed according to the parameter execution that presets before encoding by above-mentioned huffman coding method.That is, to rgb space information and executing DCT (discrete cosine transform-disperse conversion in advance) operation, and in the DCT coefficient that obtains, only choose coefficient in the scope of presetting, and abandon all the other coefficients to reduce amount of information.Therefore, above-mentioned re-quantization portion 134 will carry out the re-quantization operation to the JPEG frequency information of above-mentioned decoding, and above-mentioned all the other the DCT coefficients that abandon of interpolation (interpolation).
The JPEG frequency information of 135 pairs of above-mentioned re-quantizations of above-mentioned low pass filter portion is carried out low-pass filtering operation, and removes the noise that comprises in the JPEG frequency information of above-mentioned re-quantization.The noise that comprises in the above-mentioned JPEG frequency information mainly is distributed in the high frequency band zone and has pulse (impulse) characteristic, therefore can effectively remove noise by above-mentioned low-pass filtering operation.
Above-mentioned low pass filter portion 135 carries out low-pass filtering operation by the JPEG frequency information piece (block) with 8 * 8 (=64) size, as shown in Figure 3, above-mentioned JPEG frequency information is to carry out the DCT operation and the information of generation by the piece with 8 * 8 sizes, when above-mentioned JPEG frequency information being converted under the situation of rgb space information, will need again to carry out the IDCT operation by piece with 8 * 8 sizes.
3 describe with reference to the accompanying drawings, the DC piece refers to the piece of the DC DCT coefficient that includes 0 ordered coefficients of representing DC (direct current-direct current) composition in above-mentioned rgb space information; The AC piece refers to the piece that includes the AC DCT coefficient more than 1 ordered coefficients of representing AC (alternating current-interchange) composition in above-mentioned rgb space information.
Wherein, it includes the relevant DCT coefficient of radio-frequency component from above-mentioned DC piece piece far away more, and the AC piece that above-mentioned low pass filter portion 135 will only allow to be in the certain distance from above-mentioned DC piece passes through, and all the other AC pieces will be changed to 0.For example, only to allow from the distance of DC piece be under 1 the AC piece situation about passing through when above-mentioned low pass filter portion 135 is set at, and (0,0) DC piece, (0,1) AC piece and (1,0) AC piece in the above-mentioned JPEG frequency information will be passed through, and all the other AC pieces will be changed to 0.
The transfer function of the low pass filter portion 135 in one embodiment of the invention is as follows.
[mathematical expression]
Wherein, H () expression JPEG frequency information piece; K and l represent the coordinate of JPEG frequency information piece; D
0The distance that expression presets.
Be under the situation of too small value with above-mentioned distance setting, will becoming fuzzy (blurring) though can remove more noise picture, therefore, need be with above-mentioned distance setting for can keep the contrast (constrast) more than certain level and to remove noise.
But, except above-mentioned low-pass filtering method, also can adopt other low-pass filtering and implement the present invention.
Above-mentioned low pass filter portion 135 receives as the JPEG frequency information of frequency-domain information and carries out low-pass filtering operation, therefore, when carrying out the situation comparison of filtering operation, can reduce operand, thereby avoid producing overload and can carrying out filtering operation more rapidly in the processor etc. with the spatial domain entropy.
The JPEG frequency information of 136 pairs of above-mentioned low-pass filtering of above-mentioned IDCT portion is carried out the IDCT operation and is generated the JPEG spatial information, wherein, above-mentioned JPEG spatial information refer to the DCT coefficient of above-mentioned JPEG frequency information carry out the IDCT operation and the spatial domain obtained on image information.Above-mentioned JPEG spatial information is based on the image information of Y-Cb-Cr colour system, and wherein above-mentioned Y represents that brightness, above-mentioned Cb and Cr represent color.
Above-mentioned DCT/IDCT compresses the frequency image information that the space image information on the spatial domain converts to as the information on the frequency domain, and the said frequencies image information is restored a kind of for the conversion/inverse conversion of the space image information on the spatial domain again.Under the situation that the conversion operations of above-mentioned space image information by other kind compresses, can adopt other inverse conversion portion that carries out the inverse conversion operation accordingly with above-mentioned conversion operations to replace IDCT portion 136 among the present invention among the present invention.
The above-mentioned JPEG spatial informations of 137 pairs of above-mentioned color convertings are carried out the color conversion operation, and will generate the rgb space information of conduct and RGB colour system corresponding image information.Wherein, above-mentioned RGB colour system is and the different primary signal system of above-mentioned Y-Cb-Cr colour system that belongs to the color difference signal system.
Fig. 4 is a flow chart of removing the image restoration method of noise in the frequency image information of one embodiment of the invention.
4 describe with reference to the accompanying drawings, the JPEG frequency information of 133 pairs of inputs of Hofmann decoding portion of image restoration device 100 is carried out the Hofmann decoding operation, and the JPEG frequency information (step S100) that generation is decoded.
Subsequently, the JPEG frequency information of 134 pairs of above-mentioned decodings of re-quantization portion of image restoration device 100 is carried out the re-quantization operation, and generation is carried out the JPEG frequency information (step S110) of re-quantization.
Subsequently, the JPEG frequency information of 135 pairs of above-mentioned re-quantizations of low pass filter portion of image restoration device 100 is carried out low-pass filtering operation, and generation is removed the JPEG frequency information (step S120) of noise.
Subsequently, the JPEG frequency information of 136 pairs of above-mentioned low-pass filtering of IDCT portion of image restoration device 100 is carried out the IDCT operation, and will generate JPEG spatial information (step S130).
Subsequently, 137 pairs of above-mentioned JPEG spatial informations of the color converting of image restoration device 100 are carried out the color conversion operation, and will generate rgb space information (step S140).
Subsequently, the above-mentioned rgb space information and executing of 138 pairs of the output processing part of image restoration device 100 extract (decimation) operation, and the rgb space information that will carry out above-mentioned extraction operation is presented at the display part 120 (step S150) and the end operation of image restoration device 100.
More than be illustrated at the preferred embodiment among the present invention, but the present invention is defined in aforesaid embodiment, in the category that does not exceed basic fundamental thought of the present invention, the operator of relevant industries can carry out various deformation and application to it, and claim scope of the present invention will be limited by the content of putting down in writing in the appending claims.
The effect of invention:
According to aforesaid the present invention, under the situation that the image information that compresses by JPEG (joint photographic codingexperts group-joint image expert group) mode is restored, JPEG frequency information as the image information on the frequency domain is carried out low-pass filtering operation, make and to remove the noise that comprises in the image information of space efficiently and effectively.
Compared with the prior art the time, carry out extraction (decimation) operation of sampling (sampling) one part of pixel from RGB (red green blue) spatial information in the prior art for display space image information in liquid crystal indicator.At this moment, shown in Fig. 5 b, carry out that noise will be more outstanding in the rgb space information of extraction operation, make the time to have very poor quality with master rgb space information comparison shown in Fig. 5 a.Therefore, for the quality of the rgb space information that prevents above-mentioned demonstration because noise factor excessively reduces, together carry out filtering operation and remove the noise that comprises in the above-mentioned rgb space information with above-mentioned extraction operation in the prior art.As the filter use of carrying out above-mentioned filtering operation average filter (mean filter), median filter (median filer), composite filter (complex filter) etc. are arranged, illustrate the rgb space information of together carrying out filtering operation with above-mentioned extraction operation among Fig. 5 c.
Compare with above-mentioned prior art, in the present invention, JPEG portion carried out low-pass filtering operation to the JPEG frequency information before carrying out extraction operation, comprise noise in the JPEG frequency information hardly thereby make.Thus, when carrying out extraction operation, need not rgb space information is carried out filtering operation in addition, make the sharp image of removing noise and intimate master that to play shown in Fig. 5 d.
And, according to aforesaid the present invention, can remove the noise that comprises in the JPEG frequency information by software mode, making need not additional expenses and power consumption and the image information that compresses by the JPEG mode of real time restoration easily.
Certainly; the present invention also can have other various embodiments; under the situation that does not deviate from spirit of the present invention and essence thereof; being familiar with those of ordinary skill in the art ought can make various corresponding changes and distortion according to the present invention, but these corresponding changes and distortion all should belong to the protection range of the appended claim of the present invention.
Claims (8)
1. remove the image restoration device of noise in the image information, it is used for the space image information on the spatial domain is converted to the information on the frequency domain and the frequency image information that compresses restores, and it is characterized in that, includes following several sections:
The said frequencies image information is carried out the low pass filter portion of low-pass filtering operation in order from the said frequencies image information, to remove noise;
The inverse conversion portion that above-mentioned low pass filtered wave frequency image information is converted to above-mentioned space image information and restores.
2. remove the image restoration device of noise in the image information according to claim 1, it is characterized in that, also include:
The said frequencies image information is carried out the entropy lsb decoder of entropy decode operation;
The frequency image information of above-mentioned decoding is carried out the re-quantization operation and exported to the re-quantization portion of above-mentioned low pass filter portion.
3. remove the image restoration device of noise in the image information according to claim 2, it is characterized in that,
The said frequencies image information is the JPEG frequency information that compresses by the JPEG mode, and above-mentioned space image information is the JPEG spatial information that restores by the JEPG mode,
Above-mentioned inverse conversion portion carries out the inverse discrete cosine transform operation and restores above-mentioned JPEG spatial information above-mentioned low pass filtered wave frequency image information,
And also include above-mentioned JEPG spatial information is carried out the color conversion operation and generated the color converting of rgb space image information.
4. remove the image restoration device of noise in the image information according to claim 3, it is characterized in that, also include:
Be used to show the display part of above-mentioned rgb space information;
The output processing part of above-mentioned rgb space information being carried out extraction operation and showing in order to be suitable for above-mentioned display part.
5. the image restoration method of removing noise in the frequency image information, the image restoration method that the frequency image information that will compress as being converted to the information on the frequency domain to the space image information on the spatial domain restores, it is characterized in that, include following several steps:
The said frequencies image information is carried out the low-pass filtering step of low-pass filtering operation in order to remove the noise in the said frequencies image information;
The inverse conversion step that above-mentioned low pass filtered wave frequency image information is converted to above-mentioned space image information and restores.
6. remove the image restoration method of noise in the frequency image information according to claim 5, it is characterized in that, also include:
The said frequencies image information is carried out the entropy decoding step of entropy decode operation;
Image information to above-mentioned decoding is carried out the re-quantization step that above-mentioned low-pass filtering step was operated and moved to re-quantization.
7. remove the image restoration method of noise in the frequency image information according to claim 6, it is characterized in that,
The said frequencies image information is the JPEG frequency information that compresses by the JPEG mode, and above-mentioned space image information is the JPEG spatial information that restores by the JEPG mode,
In above-mentioned inverse conversion step, above-mentioned low pass filtered wave frequency image information is carried out the inverse discrete cosine transform operation and restored above-mentioned JPEG spatial information,
And also include above-mentioned JEPG spatial information is carried out the color conversion operation and generated the color conversion step of rgb space image information.
8. remove the image restoration method of noise in the frequency image information according to claim 7, it is characterized in that, also include: at the rgb space information of restoring, the output treatment step of to carry out extraction operation and showing in order to be suitable for showing by above-mentioned inverse conversion step.
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| KR1020050094759A KR100695003B1 (en) | 2005-10-10 | 2005-10-10 | Method for recovering image with removal of noise in frequency image data and apparatus thereof |
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| CN111127328A (en) * | 2018-10-31 | 2020-05-08 | Tcl集团股份有限公司 | Image blurring method, terminal, storage medium and processor |
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| KR100821939B1 (en) | 2006-12-22 | 2008-04-15 | 연세대학교 산학협력단 | Apparatus and method for image noise reduction |
| KR101962372B1 (en) * | 2013-04-16 | 2019-03-26 | 에스케이하이닉스 주식회사 | Method and apparatus for removing noise in image |
| EP3497925B1 (en) | 2016-08-09 | 2022-11-23 | Contrast, Inc. | Real-time hdr video for vehicle control |
| EP3837635A4 (en) * | 2018-08-14 | 2022-04-27 | Contrast, Inc. | Image compression |
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| US5737450A (en) | 1995-05-15 | 1998-04-07 | Polaroid Corporation | Method and apparatus for fast two-dimensional cosine transform filtering |
| JPH11503594A (en) * | 1996-02-05 | 1999-03-26 | フィリップス エレクトロニクス ネムローゼ フェンノートシャップ | Image data noise filter processing |
| KR20040105274A (en) * | 2003-06-04 | 2004-12-16 | 삼성전자주식회사 | Method for blocking artifact reduction included ended image based on bdct |
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| CN111127328A (en) * | 2018-10-31 | 2020-05-08 | Tcl集团股份有限公司 | Image blurring method, terminal, storage medium and processor |
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