JPH05174490A - Method for recording digital data in information recording medium and method for deciding copy of digital data - Google Patents

Abstract

PURPOSE:To decide whether data is a copy or not by recording previously the data value of a specific address reduced or increased on an original recording medium and comparing it with the data value of the specific address recorded on the testing recording medium. CONSTITUTION:The digital value of a specific picture element is increased or decreased when the source data is recorded on the information recording medium of a CD-ROM, etc. For example, when this processing is performed every other 8 picture elements in the direction of x, y of a two-dimensional picture regarding the left of top of the picture as an original point, the processing is performed to the data corresponding to the picture element of the position of a coordinate value of 8m+p, 8n+q. Respective data values of R, G, B are made to 1/2 to the original data selected in such a manner. Then, when whether the data of a certain recording medium is a copy or not is tested, the digital value is analyzed and the data is decided as a copy when only the data on the specific position is different from the value to indicate essentially to the source data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording medium in which sounds and images are stored as digital data, a digital data recording method for an information recording medium capable of copy judgment, and an information recording medium in which data is recorded by the method. The present invention relates to a method for determining whether or not data has been copied from.

[0002]

2. Description of the Related Art In recent years, when recording audio data or image data, a method has been adopted in which original data (analog data) is converted into digital data and recorded on a recording medium such as an optical disk or a CD-ROM. ing. This has the advantage that digital data can be reproduced with higher quality than analog data, and that an extremely large amount of data can be recorded on a recording medium of the same size as a record. Because there is. On the other hand, another feature of digital data is that it is possible to copy data to another recording medium without substantially deteriorating the information of the original data.

[0003]

However, since the digital data can be easily copied as described above, there is a possibility that the digital data produced by the producer such as a CD-ROM may be copied as it is. Moreover, even if the data is copied without permission of the creator, it is actually impossible to judge whether or not the data is copied. Therefore, it is an object of the present invention to provide a digital data recording method and a digital data copy determination method for an information recording medium capable of determining whether or not certain digital data is a copy of original data.

[0004]

The present invention has been made to solve the above-mentioned problems, and the invention according to claim 1 records digital data for representing a sound or an image on an information recording medium. In this case, the method is a digital data recording method for an information recording medium, characterized in that data is recorded by reducing or increasing a data value of a preset specific address.

According to the second aspect of the present invention, when recording digital data for representing a sound, an image or the like on the information recording medium, the data value is recorded by reducing or increasing the data value of the address at the preset interval. A digital data recording method for an information recording medium, characterized in that:

According to a third aspect of the invention, the data of the original information recording medium on which digital data for representing a sound or an image is recorded is compared with the data of the information recording medium to be tested to determine whether or not it is a copy. In the method, when recording digital data on the original information recording medium, data is recorded by subtracting or increasing the data value of a specific address set in advance, and the specific address recorded on the original recording medium is recorded. Digital data characterized by determining whether or not the data of the information recording medium to be tested is a copy by comparing the data value with the data value read from the address corresponding to the specific address of the information recording medium to be tested. Is a copy determination method.

According to the fourth aspect of the invention, the data of the original information recording medium on which the digital data for representing the sound or the image is recorded is compared with the data of the information recording medium to be tested to determine whether or not to copy. A method of determining, when recording digital data on an original information recording medium, data is recorded by reducing or increasing a data value of a preset specific address, and the data value is recorded on the original recording medium. The address recorded by reducing or increasing,
Copy determination of digital data characterized by determining whether or not the data of the information recording medium to be tested is a copy by comparing the data read from the information recording medium to be tested with an address whose data value has increased or decreased. Is the way.

[0008]

According to the present invention, when the original data is created, the digital data value of the preset specific address is reduced or increased so as to be deteriorated and recorded on the recording medium. In terms of image data, the number of pixels on the monitor is usually 640 x 480.
Since the amount of data is about a dot, even if the data of several dots is recorded in a deteriorated state, it is almost invisible to the human eye and the image quality is not affected. However, when the digital data of this original recording medium is copied, the data of the specific address will be copied in a deteriorated state. That is, it is possible to determine whether or not the data has been copied by checking the presence or absence of deterioration.

[0009]

Embodiments of the present invention will be described with reference to the drawings.
FIGS. 2A to 2C show a case where an image is divided into a plurality of pixels and R, G, and B digital data is set for each pixel. The gradation of each pixel is 8 bits, that is, 256 of 0 to 255.
It is represented by gradation. FIG. 2A shows source data, which is used to scan an image of a manuscript film or the like with R, G,
It is created by decomposing it into data of the three primary colors of B and performing A / D conversion. This source data is stored in a database and supplied to various media as needed. For example, a printed matter is created based on this data, or used as high-definition still image data.

In the present invention, these source data are recorded on a CD.
-When recording on an information recording medium such as a ROM, the digital value of a specific pixel is reduced or increased before recording. In this embodiment, as an example, R, G, and
It is assumed that the B value is recorded after reducing the data value by half at predetermined intervals. For example, as shown in FIG. 3, in the x and y directions of a two-dimensional image, when this processing is performed every 8 pixels with the upper left corner of the image as the origin, coordinate values (8m + p, 8n
The data corresponding to the pixel at the position represented by + q) is processed. However, m = 0, 1, 2, 3, ---, n = 0,
2, 3 and p and q represent a certain value (constant value) of 0 to 7 in this case.

The R, G, and B data values are reduced to 1/2 with respect to the data at the constant intervals thus selected. For example, if the data value of the source data is (R, G,
If the data of (B) = (100, 120, 130), it is (R, G, B) = (50, 60, 65)
And In this way, data is sampled at regular intervals, and the digital value at the sampled pixel position is reduced to 1/2 for recording. The data processed in this way will be partially degraded compared to the original data, but by setting the sampling interval and the amount of change in the data to an appropriate value, the reproduced image will be compared to that of the source data. It is possible to make it almost invisible. For example, depending on the image quality, R, G, B
Each data value of is changed at a different rate (change amount), or among the R, G, and B data, it is changed only for one or two kinds of data with less image deterioration. You can also do it. In this way, the position where the data is changed and the degree to which each of the R, G, and B data values is changed may be appropriately set, and can be arbitrarily set for each image. In this specification, the data created in the state in which the data at the predetermined position is changed is referred to as original data.

Next, the operation of testing whether or not the data recorded on a certain information recording medium is a copy of the data created as described above will be described.
When the original data such as CD-ROM is copied,
The data at the predetermined position is also copied with deterioration with respect to the source data. Conventionally, it has been human only to judge whether or not the data to be tested is a copy of the original data by looking at the image displayed on the screen of the reproducing apparatus.

In the present invention, the digital value of the digital data to be tested is analyzed and attention is paid to the data value at the set predetermined position. If the data to be tested is a copy, only the data at a specific position becomes data that is significantly different (deteriorated) from the original value for the source data. By checking whether such deterioration appears at the specific position specified when the original data was created, it is possible to determine whether the data was created by copying the original data to the copy.

In this case, if the position of the deteriorated data matches the original data even at one place, it is highly likely that the test data is copied, but it is also considered that only a part of the data is accidentally deteriorated. For this reason, it is desirable that the set constant interval, that is, (8 m +
p, 8n + q), the data corresponding to the pixel having the coordinate value represented by p, 8n + q) is checked for deterioration, and if deterioration appears periodically at the same intervals as the original data, the test target data is a copy of the original data. Can be determined.

Alternatively, the test data is compared with the source data, and the address where the test data is deteriorated with respect to the source data is specified. The address specified in this way is
It is possible to check whether the original data matches the address whose data value is deteriorated, and if the same address is deteriorated, it is possible to determine that the data to be tested is a copy of the original data.

Even if the data value is changed in whole or in part with respect to the original data by performing some image processing at the time of copying the data (in this case, the above-mentioned specific sampling point is used). The data value of will also change), and the pattern that deterioration appears at a specific position in the entire data does not change, so compare the data pattern of the test target with the data pattern of the original data recorded by the above method. By doing so, it is possible to easily determine whether or not it is a copy.

When the present invention is applied to sound data, the digital data (voltage value in this embodiment) at the set sampling position is also changed at a predetermined rate. When the data recorded in this way is copied, when the waveform of the data reproduced by the data is examined with an oscilloscope or the like, deterioration of the discontinuity point of the waveform at the set position as shown in FIG. 4 is observed. Will appear. Therefore, it can be easily determined that the data has been copied.

In this embodiment, the R, G, B image data and sound data have been described as an example. However, the present invention is not limited to this, and all other digital data can be subjected to the processing of the present invention to make a test. Whether or not the target data is a copy can be easily determined. Further, the position where the deterioration process is performed is not limited to this embodiment, and the data can be processed at any position.

[0019]

According to the present invention, it is possible to easily determine whether or not the digital data to be tested is created by copying by checking the data value of the specific address.

[Brief description of drawings]

FIG. 1 is a block diagram for explaining data processing of the present invention.

FIG. 2 is an explanatory diagram of digital image data.

FIG. 3 is an explanatory diagram of a processing position (address) of image data in this embodiment.

FIG. 4 is an explanatory diagram of processing for sound data according to the present invention.

FIG. 5 is a flowchart showing the operation of the present invention.

FIG. 6 is a flowchart showing the operation of the present invention.

Claims (4)

[Claims] 1. When recording digital data representing a sound, an image or the like on an information recording medium, the data value is recorded by reducing or increasing a data value of a preset specific address. A method for recording digital data on a medium. 2. When recording digital data representing a sound, an image or the like on an information recording medium, the data is recorded by reducing or increasing a data value of an address at a preset interval. A method for recording digital data on a recording medium. 3. A method for comparing data of an original information recording medium on which digital data for representing a sound or an image is recorded with data of an information recording medium to be tested to determine whether or not a copy is made. When the digital data is recorded on the information recording medium, the data value of the preset specific address is reduced or increased to record the data, and the data value of the specific address recorded on the original recording medium is tested. A method for determining copy of digital data, comprising determining whether or not the data of the information recording medium to be tested is a copy by comparing data values read from corresponding addresses of the information recording medium. 4. A method for comparing data of an original information recording medium on which digital data for representing a sound or an image is recorded with data of an information recording medium to be tested to determine whether or not it is a copy. When the digital data is recorded on the information recording medium, the data value is recorded by reducing or increasing the data value of the preset specific address, and the address is recorded by reducing or increasing the data value on the original recording medium. Copying of digital data characterized by determining whether the data of the information recording medium to be tested is a copy or not by comparing the data read from the information recording medium to be tested with an address whose data value increases or decreases. Judgment method.