WO2007049334A1 - Appareil d'integration/extraction de filigrane numerique - Google Patents

Appareil d'integration/extraction de filigrane numerique Download PDF

Info

Publication number
WO2007049334A1
WO2007049334A1 PCT/JP2005/019574 JP2005019574W WO2007049334A1 WO 2007049334 A1 WO2007049334 A1 WO 2007049334A1 JP 2005019574 W JP2005019574 W JP 2005019574W WO 2007049334 A1 WO2007049334 A1 WO 2007049334A1
Authority
WO
WIPO (PCT)
Prior art keywords
image
waveform
watermark
original image
embedded
Prior art date
Application number
PCT/JP2005/019574
Other languages
English (en)
Japanese (ja)
Inventor
Taizo Anan
Takafumi Edanami
Original Assignee
Fujitsu Limited
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Fujitsu Limited filed Critical Fujitsu Limited
Priority to PCT/JP2005/019574 priority Critical patent/WO2007049334A1/fr
Publication of WO2007049334A1 publication Critical patent/WO2007049334A1/fr

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N1/00—Scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission; Details thereof
    • H04N1/32—Circuits or arrangements for control or supervision between transmitter and receiver or between image input and image output device, e.g. between a still-image camera and its memory or between a still-image camera and a printer device
    • H04N1/32101—Display, printing, storage or transmission of additional information, e.g. ID code, date and time or title
    • H04N1/32144—Display, printing, storage or transmission of additional information, e.g. ID code, date and time or title embedded in the image data, i.e. enclosed or integrated in the image, e.g. watermark, super-imposed logo or stamp
    • H04N1/32149—Methods relating to embedding, encoding, decoding, detection or retrieval operations

Definitions

  • the present invention relates to an electronic permeability technique that superimposes information on an image as a permeability.
  • the digital watermark technique provides a means for embedding information in an image.
  • the watermark is superimposed on the original image P (x, y) with a watermark (such as copyright information) W (x, y), and a watermarked image Q (x, y)
  • W copyright information
  • Q watermarked image
  • Digital watermarking technology includes watermark information embedding in the frequency space by FFT (Fast Fourier Transform), using wavelet transform, and pseudo-random number (PN) sequence to add permeability information by correlation calculation. There is a technology to extract the odor (Non-Patent Documents 1 to 8).
  • FFT Fast Fourier Transform
  • PN pseudo-random number
  • a digital watermark with printing resistance reads a paper document once printed by a high-precision image reader such as a scanner, and reads the watermark information from the read image data. In this case, since it is close contact reading by a scanner, there is no deformation at the time of reading.
  • Resistance is required when dealing with brightness fluctuations due to changes in color tone that occur during printing and reading, modulation due to dithering, and large distortion due to paper deformation (especially when printing on plain paper).
  • Digital watermarks that are resistant to shooting require greater strength than printing resistance when printed and read.
  • the main factor is that it does not read closely when reading, so it cannot be assumed that the resolution of the reading device has sufficient resolution for the image.
  • the printed image is large, it is not expected to obtain a clear read image due to the influence of the shooting distance, the resolution of the camera to be shot, and camera shake.
  • the printed image and the reading surface of the reading device are parallel. In other words, it can be easily analogized that there is a trapezoidal distortion in the scanned image.
  • Sarakuko also includes curvature distortion due to lens aberrations in the reading device, which is one of the factors that cannot be avoided, although there is a difference in the degree.
  • Non-Patent Document 1 “Digital Watermark Technology” Komatsu et al .: Image Electronics Society
  • Non-Patent Document 2 "Digital Watermarking and Content Protection” Ono: Ohm
  • Non-Patent Document 3 “Digital Watermarking Using Morphological Signal Processing” Okamoto et al .: Science A Vol. J84-A No. 8 pp. 1037-1044 2001/8
  • Non-patent document 4 “Wavelet image electronic permeability method that can embed bit data”
  • Non-Patent Document 6 “Examination of printing-resistant electronic permeability method” Ejima et al .: Theory of Science A Vol. J 82- A No.7 pp. 1156-1159 1999/7
  • Non-Patent Document 7 "Digital Watermarking Using Multi-resolution Analysis and PN Sequences" Onishi et al .: Science Review D-II Vol. J80-D-II No.11 pp. 3020-3028 1997/11
  • Non-Patent Document 8 “Improvement of Digital Watermarking Using Multi-resolution Analysis of Images” Kashiwazaki et al .: Theory of Science A Vol. J85-A No.l pp.103— 111 2002/1
  • An object of the present invention is to provide an electronic permeability embedded Z extraction device that can use a robust electronic permeability having both printing resistance and photographing resistance.
  • An electronic transparency embedding device includes an original image input means for inputting original image data, an information input means for inputting embedding information to be embedded as a transparency in the original image, and a waveform modulated using the embedding information. And watermark embedding means for generating a watermarked image in which the embedding information is embedded in the original image by superimposing the generated waveform on the original image.
  • the digital watermark extraction apparatus of the present invention includes: an image input unit that inputs a watermarked image; a distortion correction unit that corrects distortion of the watermarked image; and a watermarked image in which the distortion is corrected.
  • a non-linear filter By applying a non-linear filter to the watermarked image, it is obtained by arranging a minute amplitude extracting means for extracting a minute amplitude image signal, and the minute amplitude image signal and one of the waveforms constituting the watermark. It is characterized by comprising an embedded information extraction means for extracting information embedded as a force by calculating a correlation value with the signal waveform for information extraction.
  • FIG. 1 is a diagram showing an overall configuration of a watermark embedding apparatus according to an embodiment of the present invention.
  • FIG. 2 is a diagram illustrating a flow of permeability embedding according to the embodiment of the present invention.
  • FIG. 3 is a diagram showing an example of a two-dimensional signal waveform.
  • FIG. 4 is a diagram for explaining a method of embedding a two-dimensional signal waveform as a permeability.
  • FIG. 5 is a diagram showing a configuration of a permeability extracting device.
  • FIG. 6 is a diagram for explaining the flow of watermark extraction processing.
  • FIG. 7 shows a flowchart of adaptive permeability embedding processing according to an embodiment of the present invention.
  • FIG. 8 shows a flowchart of adaptive permeability embedding processing using FFT.
  • FIG. 9 shows a flowchart of adaptive permeability embedding processing using DCT.
  • FIG. 10 is a diagram showing an image of correction of geometric distortion at the time of shooting.
  • FIG. 11 is a flowchart of a first watermark extraction process.
  • FIG. 12 is a flowchart of second watermark extraction processing.
  • FIG. 1 is a diagram showing an overall configuration of a watermark embedding device according to an embodiment of the present invention.
  • the embedded information input from the information input unit 102 is superimposed on the original image as a transparent force.
  • the embedded information is converted into digitally embedded information 101 composed of binary numbers of 0 and 1. Further, the digitized embedding information 101 is converted into a signal waveform (watermark) by the embedding processing unit 105. If the embedded information is digital information at the beginning, a different wave is applied to each of 0 and 1. Shape is assigned. In this manner, the embedded data converted into the signal waveform is added to the image signal, and is output as a watermarked image 106.
  • FIG. 2 is a diagram illustrating the flow of permeability embedding according to the embodiment of the present invention.
  • FIG. 3 is a diagram illustrating an example of a two-dimensional signal waveform.
  • FIG. 4 is a diagram for explaining a method of embedding a two-dimensional signal waveform as a watermark.
  • the embedded information 201 may be a text or a numerical value.
  • the embedded information 201 is converted into digital information 202.
  • text can be ASCII code.
  • Different waveforms as shown in the two-dimensional waveforms 203 and 204 are assigned to the symbols 1 and 0 of the digital information, respectively. Such waveforms may have different phases, different amplitude sizes, or different periods.
  • the digital information 202 is replaced by the two-dimensional waveforms 203 and 204.
  • the watermark component W (x, y) 205 is obtained.
  • the signal waveform of the watermark component 205 is superimposed on the original image 206 and output as a watermarked image 207.
  • the power waveform is embedded as the signal waveform in this way.
  • the signal waveform can have any tolerance strength by changing its period and amplitude size. Since the signal waveform W (x, y) is a noise component for a watermarked image, if the amplitude and period of the watermark component W (x, y) are large, the image quality of the watermarked image will be degraded (human eyes). Stand out). Therefore, the signal waveform W (x, y) must be a small amplitude signal.
  • the embedding method is the same as that for a one-dimensional signal (Fig. 4).
  • a method for embedding a two-dimensional signal waveform will be described with reference to FIG. That is, different two-dimensional waveforms 402 and 403 are prepared by changing the phase of the two-dimensional waveform 401.
  • the two-dimensional waveforms 402 and 403 in FIG. 4 are views of the two-dimensional signal waveform as viewed from above.
  • the two-dimensional waveform 402 is associated with bit 1 and the two-dimensional waveform 403 is associated with bit 0.
  • These are arranged like an arrangement 404 according to the information to be embedded, and the watermark 406 is generated by adjusting the amplitude of the two-dimensional signal.
  • the reason for adjusting the amplitude of the two-dimensional signal is to make the permeability inconspicuous.
  • This and the original image 405 are added to generate a watermarked image 407.
  • the watermark component can be reliably extracted by the non-linear filter, and printing resistance and photographing resistance can be obtained.
  • a two-dimensional modulation waveform as the waveform that is embedded as a permeability, it is possible to change the embedding strength more flexibly and still have robustness against resistance.
  • the two-dimensional modulation waveform in Fig. 3 is given by Note that Fig. 3 shows the state of the amplitude of the two-dimensional waveform, and the values on each coordinate axis are not particularly meaningful.
  • a block is a basic unit of embedded data, and is a two-dimensional waveform 402, 403 in FIG.
  • Level Permeability and embedding strength. The amplitude of the signal.
  • Fx, Fy is the permeability cycle period (usually 1) in the x and y directions.
  • the waveform period XI when the permeability bit is 0, the waveform period X (— 1 ).
  • the amplitude, period, and block size can be easily changed. Also, since it is a two-dimensional waveform, the watermark extraction Is very robust and distinctive.
  • FIG. 5 is a diagram showing the configuration of the permeable extractor.
  • the watermarked image 701 input to the watermark position image input unit 702 is corrected by the distortion correcting unit 703 for distortion during shooting and distortion during scanning.
  • a nonlinear error filter is applied to extract a minute amplitude signal.
  • the embedding extraction unit 705 calculates the correlation between the micro-amplitude signal and the 0 or 1 signal of the signal waveform used for embedding the permeability and the correlation value, and extracts 0 or 1 embedding information.
  • FIG. 6 is a diagram for explaining the flow of the watermark extraction process.
  • the non-linear error filter is a powerful filter that extracts noise components as well as image power. If the transparency is included as a minute signal waveform (ie noise), W (x, y) can be strongly separated from the watermarked image P (x, y) during watermark extraction. Figure 6 illustrates this concept.
  • noise a minute signal 503
  • the array 504 is an array of the signals of the two-dimensional waveforms 402 and 403 in FIG. It is possible to extract the embedded information 505 by performing a correlation operation between the minute signal 503 and the array 504.
  • the embodiment of the present invention has the advantage that the watermark component can be stably extracted by embedding the watermark component as noise that can be easily separated by a non-linear filter.
  • a low-pass filter can be considered instead of the nonlinear filter 502.
  • the nonlinear filter can more stably remove noise.
  • a watermark will be described by taking a two-dimensional waveform (PSK modulation waveform), a watermark extraction as an ⁇ error filter, and a trapezoidal geometric transformation as an example for generating a rectangle.
  • PSK modulation waveform a two-dimensional waveform
  • ⁇ error filter a watermark extraction as an ⁇ error filter
  • trapezoidal geometric transformation as an example for generating a rectangle.
  • the present invention can be realized by using a waveform, a filter, and a geometric transformation having the same properties as the above.
  • Embed watermark The transparency embedding method defines the watermark embedded image as an addition of the current image and watermark information
  • the watermark embedding pattern is:
  • Nx and Ny are the number of x and y data in the block, respectively.
  • Level watermark embedding strength
  • Fx, Fy is the watermark waveform period (usually 1) in the x and y directions.
  • the waveform period is X 1; when the permeability bit is 0, the waveform period X (-1),
  • Figure 3 shows the concrete watermark waveform of one block.
  • Watermark embedding using a two-dimensional PSK modulation waveform is performed as shown in FIG.
  • the digital signals 0 and 1 can be assigned to the two-dimensional waveform 402 and 403, respectively, and the two-dimensional PSK modulation waveform.
  • the amplitude of the array 404 it is possible to make the unevenness visually inconspicuous as shown by the watermark 406.
  • a watermark 406 is superimposed on the original image 405. As a result, a watermarked image 407 can be generated.
  • frequency analysis is performed by performing FFT and DCT (Discrete Cosine Transform). Where there is a lot of high frequency, the permeability is embedded, and where there is little high frequency, the permeability is It is also possible to perform the following processing without embedding the word.
  • FFT and DCT Discrete Cosine Transform
  • the deterioration of the watermarked image can be reduced by appropriately changing the amplitude of the watermark waveform.
  • the amplitude of the permeability waveform signal is reduced when the luminance value of the original image is flat, and the amplitude of the permeability waveform signal is increased when the luminance value is not flat. Can be prevented. Even in the case of the extraction of the force and the permeability, the flatter the brightness value, the easier it is to extract the watermark, so there is no problem even if the transparency is weak.
  • the size of the block where the transparency is added only by the strength of the transparency is also a major factor that affects the quality of the watermarked image.
  • the area of the watermark signal waveform shown in FIG. 3 can be adjusted by the parameters Nx and Ny shown in Equation (2).
  • Nx and Ny shown in Equation (2).
  • the area is large, it is conspicuous to the human eye and the image quality of the watermarked image is greatly deteriorated, but the tolerance is enhanced in terms of watermark extraction.
  • the area is small, the image quality degradation is small, but the watermark extraction tolerance is degraded. Therefore, as described in (2), when the brightness value is flat, the area is reduced to prevent image quality degradation, and when the brightness value is not flat, the area is increased to increase the watermark extraction strength. Therefore, it is possible to maintain the watermark extraction strength while preventing image quality degradation.
  • FIG. 7 shows a flowchart of the adaptive permeability embedding process according to an embodiment of the present invention.
  • step S10 the embedding information is input from the information input unit 102 (step S11), and the embedding processing unit 105 converts the input information into a watermark signal waveform (step S12).
  • step S12 the embedding processing unit 105 calculates the variance of the image signal value for each block size that is the same as the initial block size of the watermark signal waveform for the input image (step S 13).
  • the dispersion value is compared with the default threshold value (Step S14) . If the dispersion value is larger than the threshold value, the permeability is embedded with the default setting (Step S16), and conversely, According to (4), the watermark signal strength is appropriately adjusted and embedded (step S15). Decide in advance how much strength to adjust. This value can be given empirically. It can also be proportional to the variance value. In addition to adaptive embedding using the above variance values, it is possible to use FFT or DCT.
  • Figure 8 shows a flowchart of the adaptive permeability embedding process using FFT.
  • the same steps as those in FIG. 7 are denoted by the same reference numerals and description thereof is omitted.
  • the FFT is performed on the input image to calculate the power spectrum. Two thresholds are set here.
  • Threshold 1 Set a certain frequency
  • Threshold 2 Sum of spectra above the frequency set in threshold 1
  • the sum of the spectrum above the frequency exceeding the threshold 1 is calculated, and if the sum exceeds the threshold 2, the signal waveform is not embedded, embedded with a reduced amplitude, or blocked. Embedding with a reduced size (step S13, step S14).
  • Figure 9 shows a flowchart of the adaptive permeability embedding process using DCT.
  • the same steps as those in FIG. 7 are denoted by the same reference numerals, and the description thereof is omitted.
  • the adaptive embedding process in DCT is basically the same as in FFT.
  • Preparation Decide which DCT coefficient to set as high frequency
  • Threshold Sum of absolute values of the above DCT coefficients
  • DCT is calculated with the size of the embedding block size, and the sum of the absolute values of the DCT coefficients set in preparation is obtained. If the sum is equal to or greater than the threshold, select one of the following: not embedding, reducing the amplitude, or reducing the block size (step S13, step S14, etc.).
  • FIG. 10 is a diagram showing an image of correction of geometric distortion at the time of photographing.
  • the captured image is generally captured as a substantially trapezoidal area rather than being obtained as an accurate rectangular image.
  • it is necessary to detect the positions of the four corners of the image and perform inverse transformation according to the image deformation to reconstruct an almost upright image.
  • This process can be modeled as a transformation that maps a trapezoidal area to a rectangular area as shown in the captured image below.
  • the distortion image is corrected by coordinate conversion as follows.
  • ycmp (yl-yO) / B * (A * (y-y0) * (y-yO) + (A * yO + l) * (y-yO)) + y0
  • yO and yl are the y-coordinates of the lower and upper sides of the trapezoid
  • LO and L1 are the lengths of the lower and upper sides.
  • the pixel values of the pixel of interest and its surrounding pixels are compared.
  • the output of the nonlinear filter is an image from which a minute amplitude waveform has been removed. This will be described with an equation.
  • the nonlinear filter used in the embodiment of the present invention is as follows.
  • N represents the number of coefficients ⁇ force ⁇ .
  • the value Z is the average value of the pixel values (ie, a low-pass filter).
  • the pixel of interest ⁇ is output as it is as the output value z of the filter.
  • the minute vibration is removed from the pixels that are causing minute vibrations. By not doing so, the minute amplitude waveform is removed.
  • the minute signal is embedded with transparency.
  • the error filter is expressed by the following equation.
  • FIG. 11 is a flowchart of the first watermark extraction process.
  • step S 20 a watermarked image Q is input from the watermarked image input unit 702.
  • the distortion correcting unit 703 corrects the distortion of the input image.
  • step S22 a nonlinear error filter is applied to the input image to obtain a minute waveform signal image E.
  • step S23 a correlation value between the minute signal waveform and 402 and 403 is calculated to determine whether the minute signal waveform is 402 or 403.
  • FIG. 12 is a flowchart of the second watermark extraction process.
  • FIG. 12 the same steps as those in FIG. 11 are denoted by the same reference numerals, and the description thereof is omitted. Further, the flowcharts of FIGS. 11 and 12 are equivalent to each other.
  • step S22 of FIG. 11 is different.
  • Obtain the waveform image (Step S22'—2).
  • a fine signal waveform image that is transparent and embedded with information is obtained, but in Fig. 11, a minute signal waveform image can be obtained at once. It is possible to use a non-linear error filter that is devised in the above.

Landscapes

  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Signal Processing (AREA)
  • Editing Of Facsimile Originals (AREA)
  • Image Processing (AREA)

Abstract

La présente invention concerne des informations intégrées à intégrer sous forme de filigrane qui sont numérisées. Les formes d'onde ayant différentes phases sont respectivement associées à des '0' et des '1' représentatifs des informations intégrées numérisées. Les informations intégrées numérisées sont exprimées sous forme de séquence de deux sortes de formes d'onde ayant les différentes phases. En conséquence, les informations intégrées ont été converties en une forme d'onde à phase modulée. Cette forme d'onde est intégrée dans l'arrière-plan d'une image originale, produisant ainsi une image en filigrane. La forme d'onde peut être une forme d'onde à une ou deux dimensions. La forme d'onde en deux dimensions peut toutefois améliorer encore la tolérance d'impression et d'imagerie.
PCT/JP2005/019574 2005-10-25 2005-10-25 Appareil d'integration/extraction de filigrane numerique WO2007049334A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/JP2005/019574 WO2007049334A1 (fr) 2005-10-25 2005-10-25 Appareil d'integration/extraction de filigrane numerique

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP2005/019574 WO2007049334A1 (fr) 2005-10-25 2005-10-25 Appareil d'integration/extraction de filigrane numerique

Publications (1)

Publication Number Publication Date
WO2007049334A1 true WO2007049334A1 (fr) 2007-05-03

Family

ID=37967458

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2005/019574 WO2007049334A1 (fr) 2005-10-25 2005-10-25 Appareil d'integration/extraction de filigrane numerique

Country Status (1)

Country Link
WO (1) WO2007049334A1 (fr)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002354228A (ja) * 2001-05-29 2002-12-06 Mitsubishi Electric Corp 秘匿情報伝送装置、秘匿情報伝送方法、秘匿情報解読装置、電子透かし埋め込み装置および電子透かし抽出装置
JP2003101761A (ja) * 2001-09-26 2003-04-04 Canon Inc 画像処理装置及び画像処理方法
JP2003169206A (ja) * 2001-12-04 2003-06-13 Hitachi Ltd 設備情報遠隔配信方法および装置
JP2003169205A (ja) * 2001-11-30 2003-06-13 Toshiba Corp 電子透かし埋め込み方法及び装置並びに電子透かし検出方法及び装置
JP2003174556A (ja) * 2001-09-26 2003-06-20 Canon Inc 画像処理装置及び画像処理方法
JP2003338923A (ja) * 2002-05-21 2003-11-28 Canon Inc 画像印刷システム

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002354228A (ja) * 2001-05-29 2002-12-06 Mitsubishi Electric Corp 秘匿情報伝送装置、秘匿情報伝送方法、秘匿情報解読装置、電子透かし埋め込み装置および電子透かし抽出装置
JP2003101761A (ja) * 2001-09-26 2003-04-04 Canon Inc 画像処理装置及び画像処理方法
JP2003174556A (ja) * 2001-09-26 2003-06-20 Canon Inc 画像処理装置及び画像処理方法
JP2003169205A (ja) * 2001-11-30 2003-06-13 Toshiba Corp 電子透かし埋め込み方法及び装置並びに電子透かし検出方法及び装置
JP2003169206A (ja) * 2001-12-04 2003-06-13 Hitachi Ltd 設備情報遠隔配信方法および装置
JP2003338923A (ja) * 2002-05-21 2003-11-28 Canon Inc 画像印刷システム

Similar Documents

Publication Publication Date Title
Kutter et al. Fair benchmark for image watermarking systems
US6101602A (en) Digital watermarking by adding random, smooth patterns
US7065237B2 (en) Image processing apparatus and method
Hosam Attacking image watermarking and steganography-a survey
JP2002247344A (ja) 画像処理方法及び装置
Kutter et al. Fair evaluation methods for image watermarking systems
US6831990B2 (en) System and method for image tamper detection via thumbnail hiding
KR100864997B1 (ko) 이미지 처리 방법 및 디바이스
AU2002211634A1 (en) Halftone watermarking and related applications
Khalifa et al. A robust non-blind algorithm for watermarking color images using multi-resolution wavelet decomposition
Riad et al. Robust fourier watermarking for id images on smart card plastic supports
Vaishnavi et al. Image tamper detection based on edge image and chaotic arnold map
JP6937010B2 (ja) 電子透かし装置および方法
JP2018207247A (ja) 電子透かし装置および方法
WO2007049334A1 (fr) Appareil d'integration/extraction de filigrane numerique
Chandrasekaran et al. Applying reversible data hiding for medical images in hybrid domain using haar and modified histogram
Mirza et al. A new hybrid domain based print-scan resilient image watermarking technique
Mettripun et al. Method of rearranging watermarked pixels for printed and scanned watermarked documents
CN112767227B (zh) 一种可抗屏幕拍摄的图像水印方法
Genov Digital watermarking of bitmap images
JP2019004313A (ja) 電子透かし装置および方法
Ahmad et al. Watermark extraction under print-cam process using wave atoms based blind digital watermarking
Chun et al. A robust printed image watermarking based on iterative halftoning method
Pramoun et al. Improved image watermarking using pixel averaging and unbiased retrieval
Chang et al. Combined watermarking and fingerprinting technologies for digital image copyright protection

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application
NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 05799282

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: JP