WO2010093225A2 - Data compression / decompression device and method thereof - Google Patents

Abstract

The present invention provides a data compression / decompression device and a method thereof. For this purpose, the present invention: compresses data through encoding after hiding the information thereof, extracts hidden information from decoded data after decoding a compressed packet, and restores binary data. Furthermore, the present invention provides a structure for converting the data with hidden information into a binary code, a compression method for encoding and packing the binary data, and a restoration method for decoding the encoded data that comprises the steps of converting the decoded data into an m-array row information symbol and restoring a binary information bit row from the m-array information symbol row.

Description

Data Compression / Decompression Device and Method

TECHNICAL FIELD The present invention relates to apparatus and methods for processing data, and more particularly, to a codec apparatus and method for compressing or decompressing data using an information hiding technique.

In general, various compression techniques and decompression (hereinafter, referred to as "restore") techniques are applied or proposed in electronic equipment for processing data. The attempt to reduce the amount of data as described above is based on aspects for efficiently using the capacity of the recording medium for recording data, aspects for providing ease of delivery, and the like.

Typically, the methods of compressing data to the highest level require not only very complex data processing devices, but also often slow processing. On the other hand, low-level data compression methods are not only fast but also relatively complex in hardware.

Therefore, conventionally, a data compression technique has been selected and used to obtain a desired level of quality in consideration of hardware complexity and processing time. However, in the future, it is urgent to prepare a compression technique and a corresponding restoration technique that can achieve a high level of quality while reducing hardware complexity and processing time.

The present invention proposes a data compression device and method and a decompression device and method corresponding thereto which can reduce not only the processing time but also the complexity of hardware by using an arithmetic operation.

The present invention proposes a data compression apparatus and method and a corresponding decompression apparatus and method which can reduce not only processing time but also hardware complexity by using information hiding.

The present invention proposes a data compression apparatus and method for concealing information by a binary operation, and decrementing an information string having a binary number enhanced by the information concealment into a binary bit string, and a decompression apparatus and method corresponding thereto.

The present invention proposes an apparatus and method for compressing data by converting data consisting of binary bit strings into information strings of a desired decimal number, and a decompression apparatus and method corresponding thereto.

According to an embodiment of the present invention, the data compression apparatus determines a target hidden symbol to be hidden with respect to a target hidden symbol having a predetermined value among hidden symbols, and determines the target hidden symbol and the target hidden symbol. And an information hiding portion that replaces the value of the target hidden symbol with a symbol value corresponding to the combination of the hidden symbol.

In addition, the data compression method according to an embodiment of the present invention, the process of determining the target hidden symbol to be hidden for the target hidden symbol having a predetermined value among the hidden symbols from the hidden symbols, and the target hidden symbol And substituting the value of the target hidden symbol with a symbol value corresponding to the combination of the target hidden symbol.

In addition, the apparatus for restoring data according to an exemplary embodiment of the present invention includes an information restoring unit for restoring a hidden symbol and a hidden symbol from an information hidden symbol having a predetermined value among the information hidden symbols constituting the m information hidden symbol string. Here, the predetermined value is characterized in that the minimum value and the highest value that the information concealment symbol can have.

In addition, the data recovery method according to an embodiment of the present invention includes the step of recovering the hidden symbol and the hidden symbol from the information hidden symbol having a predetermined value among the information hidden symbols constituting the m information hidden symbol string; Here, the predetermined value is characterized in that the minimum value and the highest value that the information concealment symbol can have.

The present invention allows lossless compression with excellent compression performance while reducing hardware complexity and processing time. On the other hand various other effects will be disclosed directly or implicitly in the detailed description of the embodiments of the present invention to be described later.

1 is a diagram illustrating a system for lossless data compression and decompression according to an embodiment of the present invention;

2 is a view showing the configuration of a compression device according to a first embodiment of the present invention;

3 is a diagram illustrating a control flow for data compression in a compression device according to a first embodiment of the present invention;

4 is a diagram illustrating examples of separating a hidden information column and a hidden information column from an information string input for an embodiment of the present invention;

FIG. 5 is a diagram showing other examples of separating a hidden information column and a hidden information column from an information string input for an embodiment of the present invention; FIG.

6 to 10 show examples for concealing information according to a compression technique proposed by an embodiment of the present invention.

11 is a view showing the configuration of a compression device according to a second embodiment of the present invention;

12 and 13 illustrate examples of a binarization operation in a compression device according to a second embodiment of the present invention;

14 is a diagram showing a configuration of an encoding unit constituting a compression device according to a second embodiment of the present invention;

15 and 16 illustrate an example of converting a hexadecimal number from an hexadecimal converter in an encoder constituting a compression apparatus according to a second embodiment of the present invention;

17 is a diagram illustrating a control flow for data compression in a compression device according to a second embodiment of the present invention;

18 is a view showing the configuration of a restoration apparatus according to the first embodiment of the present invention;

19 is a diagram illustrating a control flow for data restoration in a restoration apparatus corresponding to a compression apparatus according to a first embodiment of the present invention;

20 to 26 show examples for restoring information according to a restoration technique proposed by an embodiment of the present invention;

27 and 28 illustrate examples of generating a binary information bit string by combining a hidden information string and at least one hidden information string according to an embodiment of the present invention;

29 is a view showing the configuration of a decompression device corresponding to a compression device according to a second embodiment of the present invention;

30 is a diagram showing the configuration of a decoding unit constituting a decompression device according to a second embodiment of the present invention;

31 and 32 illustrate an example of converting a hexadecimal number from a decimal converter in a decoder constituting a decompression device according to a second embodiment of the present invention;

33 and 34 are views showing an example of the m-evolution operation in the decompression device according to the second embodiment of the present invention;

35 is a view illustrating a control flow for data restoration in a restoration apparatus corresponding to a compression apparatus according to a second embodiment of the present invention.

If it is determined that the detailed description may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted. Terms to be described later are terms defined in consideration of functions in the present invention, and may be changed according to intentions or customs of users or operators. Therefore, the definition should be made based on the contents throughout the specification.

In the following embodiment of the present invention, a compression technique for compressing an information bit string to generate an information packet and a restoration technique for generating an information bit string by recovering the compressed information packet will be described in detail.

1 shows a system for lossless data compression and decompression according to an embodiment of the present invention.

Referring to FIG. 1, the data compression device 110 outputs a compressed information string Z by compressing an information string X to be compressed using an information hiding technique. The data recovery apparatus 120 extracts the hidden information from the compressed information string Z and restores the information string X before being compressed.

Hereinafter, terms to be used in describing the embodiments of the present invention are first defined as follows.

Information concealment: technology that hides information in addition to data such as images, audio, and video

Hidden symbols: symbols used to conceal other information

-Hidden symbol column (or hidden information column): a symbol string consisting of hidden symbols

-The target hidden symbol: a hidden symbol selected for concealing information among the hidden symbols constituting the hidden symbol string

-Hidden symbol: a symbol to be hidden to the hidden symbol

Hidden symbol string (or hidden information column): a symbol string composed of hidden symbols

A target hidden symbol: a selected hidden symbol among the hidden symbols constituting the hidden symbol string for concealing the target hidden symbol

Reduction: Binary data is generated by binarizing the ternary data or binary data is generated by binarizing the ternary data. At this time, the data subject to binarization can have any number except binary.

Meanwhile, terms that are not defined above but to be used in the detailed description to be described below should be interpreted based on the contents throughout the specification.

Hereinafter, various embodiments of a compression and decompression technique proposed by the present invention will be described in detail with reference to the accompanying drawings.

A. Compression Technology

In the following description, a target hidden symbol to be concealed for a target hidden symbol having a set value among hidden hidden symbols is determined from hidden symbols, and a symbol value corresponding to a combination of the target hidden symbol and the target hidden symbol. Hereinafter, various embodiments of a compression technique for substituting the value of the target hidden symbol will be described in detail.

A-1. First embodiment (compression technique)

2 shows a configuration of a compression device according to a first embodiment of the present invention.

Referring to FIG. 2, the bit separator 210 takes an information bit string X as an input, and the first hidden information string from the information bit string X.

And at least one concealed information column

or

Separate (n≥1).

Where the hidden information column

Is the first hidden information column of the at least one hidden information column

Means the first information column to hide the hidden information column

or

Denotes a column of hidden information to be hidden in the hidden information column.

remind

And above

or

In the subscript means the index of the information column, and the superscript means the decimal of the information column. The index of the corresponding information column denoted by the subscript corresponds to the number of times information concealment has been made. For example, the first hidden information column and the hidden information column before the information concealment is made.

Wow

The subscript in is zero. However, once information concealment has been made,

Wow

The subscript in is 1. Where the hidden information column

You can see that the superscript of also changes to n + 2. That is, each time information concealment is made, the number of values constituting the hidden information string increases by one.

And the first hidden secret information column

The number of bits and the hidden information string constituting

or

The number of bits constituting the can be arbitrarily set. Only the above concealed information column

or

The first hidden information column when determining the number of bits that constitute

Consider the number of bits with a value of 0 in. Also avoid hidden information columns or

The number of bits or symbols that make up the hidden information column

or

It must be larger than the number of bits constituting.

4 and 5 illustrate examples of separating the hidden information string and the hidden information string from the information string input for an embodiment of the present invention. 4 illustrates an example of sequentially separating the hidden information column and the hidden information column from the input information string, and FIG. 5 shows an example of separating the hidden information column and the hidden information column in parallel from the input information column. have.

First, referring to FIG. 4, the first hidden information string is separated by separating a predetermined number of bits from the most significant bit (MSB) of the input information string X.

Will output And the first hidden information column

First hidden information string by separating a predetermined number of bits from the MSB of the information column X except for

Will output Then the first hidden information column

And the first concealed information column

Second hidden information column by separating a predetermined number of bits from the MSB of the information column X except for

Outputs Meanwhile, additional hidden information columns may be output from the remaining information columns X as necessary.

Next, referring to FIG. 5, each bit selected from the most significant bit (MSB) of the input information string X is first hidden information column.

And the first hidden information column

And second hidden information columns

To sequentially. If a bit with a bit value of 1 is selected, the corresponding hidden information column

And the first hidden information column

And second hidden information columns

To the corresponding information column. And the next selected bit is the first hidden information string.

To be sequentially distributed again.

In FIG. 5, two hidden information columns are assumed, but the same applies to a case where more hidden information columns are to be separated. Also the first hidden information column

And the first hidden information column

And second hidden information columns

The total number of bits to distribute to can be determined in advance as needed. Only the first hidden information column in determining the total number of bits

It may be desirable to consider the number of bits and the distribution of bits having a value of 1 or the number of bits having a bit value of 0 and the like.

When the plurality of hidden information strings are generated, the bit separator 210 may not output the generated plurality of hidden information strings at the same time, but may sequentially output the plurality of hidden information strings in consideration of an information hiding operation.

The first switch S / W # 1 is the first hidden information string output from the bit separator 210.

Is transmitted to the information concealment unit 220 or the information symbol string from which the information concealment outputted from the information concealment unit 220 is performed.

Performs an operation for feeding back to the information concealment unit 220.

That is, the first switch S / W # 1 is the first hidden information string output from the bit separator 210.

The information symbol string in which the information concealment outputted from the information concealment unit 220 after being transmitted to the input of the information concealment unit 220 is performed.

Form a path for delivering to the input of the information concealment unit 220.

The second switch S / W # 2 is an information symbol string in which information hiding output from the information hiding unit 220 is performed.

The control unit performs an operation of transmitting the information to the input of the information hiding unit 220 or to the encoder 230. In this case, the information symbol string in which information concealment is transmitted to the encoder 230 is

Can be defined as Here, m is the order of the information symbol string to be finally obtained through the information concealment, it can be defined as n + 2. For example, if information concealment has been performed once (n = 1), m is 3.

Operation of the first switch (S / W # 1) and the second switch (S / W # 2) associated with the number of information concealment for information compression according to an embodiment of the present invention can be summarized as shown in Table 1 below. Can be.

Table 1

In Table 1, the off state of S / W # 1 is a state in which a path for inputting the output of the bit separator 210 to the information concealment unit 220 is formed, and the on state of S / W # 1 is information. The path for inputting the output of the concealment unit 220 to the information concealment unit 220 is formed. In Table 1, the off state of S / W # 2 is a state in which a path for inputting the output of the information hiding unit 220 to the encoder 230 is formed, and the on state of S / W # 2 is information. A path for transmitting the output of the concealment unit 220 to the S / W # 1 is formed.

However, the operation of the S / W # 1 and the S / W # 2 is not limited to the above-described and should not be interpreted. That is, even if the operations of the S / W # 1 and the S / W # 2 performs the opposite operation as described above, it is apparent to those skilled in the art that there is no difficulty in implementing the embodiment of the present invention.

On the other hand, the control of the S / W # 1 and the S / W # 2 may be made by a configuration for controlling the overall operation of the equipment having a switching controller or compression device provided separately.

The information concealment unit 220 is a column of hidden information

or

As the input, and as the hidden information column

or

As input.

The information concealment unit 220 is a hidden information string as one input.

or

Hidden information column that is another input to

or

Perform the operation to hide the.

6 to 10 show examples for concealing information according to a compression technique proposed by an embodiment of the present invention. That is, in FIG. 6, FIG. 7, and FIG. 9, the hidden information string of binary numbers.

Hidden information columns in binary

An example for concealing an is shown. In FIG. 8 and FIG.

Hidden information columns in binary

It shows an example to conceal the.

The information concealment shown in Figs. 6 to 10 is a hidden information string.

or

A bit value or a symbol value existing at a specific position of 0 is a corresponding hidden information column.

or

It is made when the bit value existing at a specific position of 0 is zero. And avoid hidden information columns

or

A bit value or a symbol value existing at a specific position of 0 is a corresponding hidden information column.

or

The information concealment is made even when the bit value existing at a specific position of X has an arbitrary value except for zero. But avoid hidden information columns

or

When the bit value or the symbol value existing at a specific position has any value except 0, the random value is kept as it is, so that information concealment is not made.

Referring first to FIG. 6, the values of the first, second bits, and fourth to eleventh bits in the hidden information string U are commonly 0. Therefore, the information symbol string L is generated by substituting the value of each of the first, second and fourth to eleventh bits with the value of the corresponding bit in the hidden information string V. FIG.

For example, since the value of the first bit of the hidden information string V corresponding to the first bit of the hidden information string U is 0, the value of the first bit of the information symbol string L is determined to be zero. However, since the value of the third bit of the hidden information string V corresponding to the fourth bit of the hidden information string U is 1, the value of the fourth bit of the information symbol string L is determined to be 1.

Meanwhile, the value of the third bit in the hidden information string U is 1. Therefore, the third bit value of the information symbol string L is determined as 1 regardless of the hidden information string V. FIG.

As described above, the bit value in the information symbol string L is determined to be 1 in two cases. Accordingly, in order to restore the information symbol string L, symbol identification information for distinguishing the two cases is required. As an example, when the bit value of the information symbol string L is determined to be 1 because of the hidden information bit having the value of 1, the symbol identification information M is set to 0, and the bit of the information symbol string L is due to the hidden information bit having the value of 1. If the value is determined as 1, the symbol identification information M is set to 1. Therefore, according to FIG. 6, the symbol identification information M is determined as '011'.

If the number of bits of the hidden information string U and the number of bits of the hidden information string V do not coincide with each other, flag information for identifying the specific bit is not required. For example, when the number of bits of the hidden information column U and the number of bits of the hidden information column V match, the flag information F is set to 0, and the number of bits of the hidden information column U and the number of bits of the hidden information column V do not match. The flag information F is set to '1'. In the case of FIG. 6, the flag information F will be set to one.

Therefore, the data finally generated through the information concealment is the length information of the symbol identification information M

And payloads including header information including flag information (F), symbol identification information (M), and information symbol string (L).

Referring to Figure 7, the hidden information column

MSB value and hidden information column

Read the MSB value of. Where the hidden information column

The MSB value of 0 is the hidden information column

Since the MSB value of 0 is 0, the information symbol column to be generated by information hiding

The MSB of is set to zero. This causes the hidden information column

The concealed information column in the MSB

It can be seen that the MSB of is concealed.

Then the hidden information column

Read the second bit value of. Where the hidden information column

Since the second value of is 1, the information symbol column to be generated by information hiding

The second symbol value of is set to 1.

And the hidden information column

Third bit value of the and said concealed information column

Read the second bit value of. Where the hidden information column

The third bit value of 0 is the hidden information column

Since the second bit value of is 0, the information symbol column to be generated by information hiding

The third symbol value of is set to 0. This causes the hidden information column

The concealed information column in the third bit of

We can see that the second bit of is hidden.

The hidden information column

The fourth through sixth bit values of are all zeros and corresponding hidden information columns

Since all the third to fifth bit values of 0 are also 0, information concealment is also performed for the corresponding bits.

But the said hidden information column

7th bit value of 0 or the hidden information column

Since the sixth bit value of is 1, the information symbol string to be generated by information hiding

The seventh symbol value of is set to 2.

Hidden information column as can be seen in the above example

Bit value of and corresponding hidden information column

If the bit values of are all zeros, the information symbol string to be generated by information hiding

The corresponding symbol value of is set to 0.

But avoid hidden information columns

Information symbol string to be generated by information hiding if the bit value of 1 is 1

The corresponding symbol value in is set to 1, and the hidden information column

If the bit value of is 1, the information symbol string to be generated by information hiding

The corresponding symbol value of is set to 2. The concealed information column

If the bit value of is 1, the corresponding hidden information column

It can be seen that the bit value of is hidden.

As such, the hidden information column

Hidden information columns with a bit value of 1

When the bit value of 1 is 1, different symbol values are set in order to allow restoration to be performed separately during data restoration.

Thus, the information symbol string generated by the above

The order of the symbols constituting the symbol is ternary.

Referring next to FIG. 8, the hidden information column

The first symbol value in is 0 or a hidden information column

Since the first bit value of is 1, the information symbol column to be generated by information hiding

The first symbol value of is set to 3. In this case, setting the corresponding symbol value to 3 means that the hidden information column

This is to use the lowest order value that is not used in.

Then the hidden information column

Read the second symbol value. Where the hidden information column

Since the second symbol value of is 1, the information symbol column to be generated by information hiding

The second symbol value of is set to 1.

And the hidden information column

Third symbol value of the and the hidden information column

Read the second bit value of. Where the hidden information column

Third symbol value of the and the hidden information column

Since the second bit values of are all zeros, the information symbol column to be generated by information hiding

The third symbol value of is set to 0. This causes the hidden information column

Said concealed information column in the third symbol of

We can see that the second bit of is hidden.

The hidden information column

The fourth through sixth symbol values of are all zeros and corresponding hidden information columns

Since all the third to fifth bit values of 0 are also 0, information concealment is also performed for the corresponding bits.

But the said hidden information column

Since the seventh symbol value of is 2, the information symbol column to be generated by information hiding

The seventh symbol value of is set to 2.

Hidden information column as can be seen in the above example

The symbol value of and the corresponding hidden information column

If the bit values of are all zeros, the information symbol string to be generated by information hiding

The corresponding symbol value of is set to 0.

But avoid hidden information columns

The information symbol column to be generated by information hiding when the symbol value of 1 is 1.

The corresponding symbol value of is set to 1, and the hidden information column

The information symbol column to be generated by information hiding if the symbol value of is 2

The corresponding symbol value in is set to 2, and the hidden information column

If the bit value of is 1, the information symbol string to be generated by information hiding

The corresponding symbol value of is set to 3. The concealed information column

If the bit value of is 1, the corresponding hidden information column

It can be seen that the bit value of is hidden.

As such, the hidden information column

And hidden information columns when the symbol values of are 1 and 2.

When the bit value of 1 is 1, different symbol values are set in order to allow restoration to be performed separately during data restoration.

Thus, the information symbol string generated by the above

The order of the symbols constituting the symbol is a hexadecimal number.

Meanwhile, in the example shown in FIG. 9 and FIG. 10, detailed description will be omitted as the information is concealed by the same method as described above with reference to FIGS. 7 and 8. In FIG. 9 and FIG. 10 only, the hidden information string used in FIGS. 7 and 8 is used.

And concealed information columns

Hidden information columns different from

And concealed information columns

There is only a difference that is used.

M-information symbol string output from the information concealment unit 220 as described above.

Is input to the encoder 230 through the second switch (S / W # 2).

The encoder 230 is a m-information symbol string input from the information concealment unit 220

Inputs the m-information symbol string

Is compressed by a predetermined coding scheme and output.

As an example, an entropy coding technique may be applied to the encoder 230. The entropy coding technique is a coding technique in which a short code is assigned to a symbol having a high frequency and a long code is assigned to a symbol having a low frequency. The entropy coding technique is also called a variable-length coding technique.

Meanwhile, the entropy coding scheme only considers the frequency of symbols. As the entropy coding scheme, any one of a Huffman coder and an arithmetic code coder may be used. The entropy coding technique requires optimal knowledge of the appearance frequency of each symbol in advance to enable optimal compression. In this case, when Huffman coding is used, only one codeword of integer length is allowed because one codeword is assigned to each symbol.

3 shows a control flow for data compression in the compression apparatus according to the first embodiment of the present invention.

Referring to FIG. 3, in operation 310, the compression apparatus receives a binary information bit string from an external source. Thereafter, the compression apparatus extracts the hidden information string from the input binary information bit string in step 312, and extracts the hidden information string from the remaining binary information bit string after extracting the hidden information string in step 314. . At this time, the count value n for counting the number of information concealment is set to 0.

In operation 316, the compression apparatus hides the extracted hidden information string from the extracted hidden information string to generate a m-information symbol string. In this case, m is a constant representing the essence of the generated information symbol string, and has a value of n, which is a hidden number count value, plus two. That is, each time information hiding is performed, the number of generated information symbol strings is increased by one.

In operation 318, the compression apparatus determines whether the base number of the generated information symbol string is a desired number. That is, since the information concealment has been performed so far, the compression apparatus will determine that the desired decimal number is 3 when the order of the information symbol string to be finally obtained is three. However, if it is desired to obtain an information symbol string having a higher order, the compression apparatus proceeds to step 320 and increases n by 1 and returns to step 314.

Upon returning to step 314, the compression apparatus extracts a new hidden information string from the remaining binary information bit strings excluding the previously hidden hidden information string and the hidden information string. In addition, the newly extracted concealment information is further concealed to the previously generated information symbol string, thereby generating an information symbol string having an increased one.

When the compression apparatus determines that the information symbol string of the desired decimal number is obtained in step 318, the compression apparatus proceeds to step 322 and performs encoding on the obtained information symbol string. In this case, encoding may be performed by an entropy compression technique. The entropy compression technique may use any of Huffman code or arithmetic code coder, as described above.

In operation 324, the compression apparatus generates an information packet through packing of the information symbol string compressed through encoding.

A-2. Second Embodiment (Compression Technology)

11 shows a configuration of a compression device according to a second embodiment of the present invention. Reference numerals 1110, 1120, and the first and second switches 1110, 1120, and the first and second switches of the components of the compression apparatus shown in FIG. In FIG. 11, the first and second encoders corresponding to the reference numerals 1140 and 1150 differ from only the input data, and perform the same operations as the encoder corresponding to the reference numeral 230 in FIG. 2.

Therefore, it should be noted that the detailed description of the configuration is omitted in the operation description according to the second embodiment of the present invention to be described later.

Referring to FIG. 11, a m-information information symbol string outputted by information hiding by the information hiding unit 1120 is output.

Is input to the binarization unit 730 through the second switch (S / W # 2).

The binarization unit 1130 is a binary information symbol string input from the information concealment unit 1120.

Binarization is performed, and two binary information symbol strings are output through the binarization. One of the two binary information symbol strings output from the binarization unit 1130 is a data information symbol string, and the other is an identification information symbol string.

The data information symbol string may be the input binary information symbol string.

Binary information symbol string for distinguishing each symbol of 0 or not. The identification information symbol string is a binary information symbol string having information for identifying a value of a corresponding symbol when a specific symbol is not 0 by the data information symbol string.

12 and 13 show examples of a binarization operation in the compression device according to the second embodiment of the present invention. That is, in Fig. 12, a ternary information symbol string

Column of data information symbols from binary

Information symbol columns in binary and binary

Shows an example of generating a symbol, and in FIG.

Column of data information symbols from binary

Information symbol columns in binary and binary

Shows an example of creating a.

In the binarization operations illustrated in FIGS. 12 and 13, when a symbol value existing at a specific position of an m-information symbol string is 0, a corresponding symbol value of a binary data information symbol string is set to 0. However, if a symbol value existing at a specific position of the m-th information string is not 0, the corresponding symbol value of the binary data information symbol string is set to 1.

The symbol value of the binary identification information symbol string corresponding to the symbol of the binary data information symbol string set to 1 is set to a previously promised value.

As an example, assuming that the information symbol string is a ternary number, if a symbol value existing at a specific position of the information symbol string is 1, the previously promised value to be set to the corresponding symbol value of the binary identification information symbol column is 0. . If the symbol value existing at the specific position of the information symbol string is 2, the previously promised value to be set to the corresponding symbol value of the binary identification information symbol string is 1.

However, assuming that the information symbol string is a hexadecimal number, if the symbol value existing at a specific position of the information symbol string is 1, the previously promised value to be set to the corresponding symbol value of the binary identification information symbol string is 0. If the symbol value existing at the specific position of the information symbol string is 2, the previously promised value to be set to the corresponding symbol value of the binary identification information symbol string is 10. If the symbol value existing at the specific position of the information symbol string is 3, the previously promised value to be set to the corresponding symbol value of the binary identification information symbol string is 11.

First, referring to FIG. 12, a ternary information symbol string

Read the first symbol value of. Where the information symbol string

Data Information Symbol column because the first symbol value in is 0

The first symbol value of is set to zero. In this case, an identity information symbol column

Is not generated.

Then the information symbol string

Read the second symbol value. Where the information symbol string

Since the second symbol value of is not 0, the data information symbol column

The second symbol value of is set to 1. In this case, the information symbol string

The identification information symbol column because the second symbol value of was 1

The first symbol value of is set to zero.

The information symbol string

Since the third to sixth symbol values of 0 are all zeros, the data information symbol string

The third through sixth symbol values of are all set to zero. In this case, the identification information symbol string

Is not generated.

Finally the information symbol column

Read the seventh symbol value. Where the information symbol string

The seventh symbol value of is not zero, so the data information symbol column

The seventh symbol value of is set to one. In this case, the information symbol string

Since the seventh symbol value of was 2, the identification symbol column

The second symbol value of is set to 1.

Thus, finally, the data information symbol column in binary

"0100001" is generated, and the binary identification information symbol string

The furnace generates "01".

Next, referring to FIG. 13, an information symbol string of a hexadecimal number is used.

Read the first symbol value of. Where the information symbol string

The data information symbol column is because the first symbol value of is not 0.

The first symbol value of is set to 1. In this case, the information symbol string

The identification information symbol column because the first symbol value of was 3

The first symbol value of is set to 11.

Then the information symbol string

Read the second symbol value. Where the information symbol string

Since the second symbol value of is not 0, the data information symbol column

The second symbol value of is set to 1. In this case, the information symbol string

The identification information symbol column because the second symbol value of was 1

The second symbol value of is set to 0.

The information symbol string

Since the third to sixth symbol values of 0 are all zeros, the data information symbol string

The third through sixth symbol values of are all set to zero. In this case, the identification information symbol string

Is not generated.

Finally the information symbol column

Read the seventh symbol value. Where the information symbol string

The seventh symbol value of is not zero, so the data information symbol column

The seventh symbol value of is set to one. In this case, the information symbol string

Since the seventh symbol value of was 2, the identification symbol column

The second symbol value of is set to 10.

Accordingly, “1100001” is finally generated as a binary data information symbol string, and “11010” is generated as a binary identification information symbol string.

The data information symbol string generated by the binarization unit 1130 as described above.

Is transmitted to the first encoding unit 1140, and the identification information symbol sequence generated by the binarization unit 1130

Is transmitted to the second encoding unit 1150.

The first encoder 1140 is a data information symbol string input from the binarizer 1130.

Is input and the data information symbol string

Is compressed by a predetermined coding scheme and output.

In addition, the second encoder 1150 is an identification information symbol string input from the binarizer 1130.

As an input, and the identification information symbol string

Is compressed by a predetermined coding scheme and output.

14 illustrates a configuration of an encoding unit constituting a compression device according to a second embodiment of the present invention. The encoder shown in FIG. 14 is a data information symbol string

It is assumed that the first encoding unit 1140 having an input as. But identifying information symbol column

It is apparent that the configuration of FIG. 14 may be equally applied to the second encoding unit 1150 having the input.

Referring to Fig. 14, the decimal converter 1410 includes a data information symbol string.

Is inputted, and the input data information symbol string

Convert the decimal number of. That is, the input data information symbol string

Since hexadecimal is binary, the hexadecimal converter 1410 is a string of data information symbols having a ternary number or higher.

Outputs

15 and 16 illustrate an example of converting a hexadecimal number from an hexadecimal converter in an encoder constituting a compression device according to a second embodiment of the present invention. That is, in Figure 15 binary data information symbol string

Column of data information symbols in hexadecimal

16 shows an example of converting to a binary data information symbol string.

Data information symbol columns in octal

An example of converting to is shown.

First, referring to FIG. 15, a binary data information symbol string

The symbols constituting the sequential group are composed of two symbols. The symbol values corresponding to each group are converted into the symbol of the hexadecimal number.

I.e. binary data information symbol

The first and second symbols in the set are 10, so the hexadecimal column of data information symbols to be generated

Set the first symbol value of to 2.

And the data information symbol string of the binary number.

Since the bundle of the third and fourth symbols of, and the bundle of the fifth and sixth symbols is 00, the hexadecimal data information symbol string to be generated

Set the second and third symbol values of to 0.

The data information symbol string of the binary number

Since the bundle of the seventh and eighth symbols of is 01, the hexadecimal data information symbol string to be generated is

Set the fourth symbol value of to 1.

The data information symbol string of the binary number

The bundle of the ninth and tenth symbols of 11 is 11, and thus the hexadecimal data information symbol string to be generated is

Set the fifth symbol value of to 3.

As described above, the binary data information symbol string

A string of hexadecimal data information symbols of "20013012" as a result of the decimal conversion for. Can be generated.

Next, referring to FIG. 16, a binary data information symbol string

Combining the symbols constituting the sequence by three symbols. Then, symbol values corresponding to each group are converted into octal symbols.

I.e. binary data information symbol

Since the bundle of the first to third symbols of and the bundle of the tenth to tenth symbols of 100 are 100, the octal data information symbol column to be generated is

Set the first symbol value and the fourth symbol value of to 4.

And the data information symbol string of the binary number.

Since the bundle of the fourth to sixth symbols of and the bundle of the sixteenth to eighteenth symbols is 000, the data information symbol column of the octal number to be generated is

Set the second and sixth symbol values to 0.

The data information symbol string of the binary number

Since the bundle of the seventh through ninth symbols of and the bundle of the thirteenth through fifteenth symbols are 011, the data information symbol column of the octal number to be generated is

Set the third and fifth symbol values of to 3.

As described above, the binary data information symbol string

A string of octal data information symbols of "403430" as a result of the decimal conversion for.

Can be generated.

Data Information Symbol Column, Converted to Octal or Octal, as discussed above

Is input to the entropy encoder 1420. The entropy encoder 1420 is a data information symbol string converted to a hexadecimal number or an octal number.

Inputs the data information symbol string converted to the hexadecimal or octal number

Compressed data information symbol string by entropy coding

Outputs

Compressed data information symbol string output from the first encoder 1140

And a compressed identification information symbol string output from the second encoder 1150.

Is transmitted to the information packing unit 1160.

The information packet unit 1160 is a compressed data information symbol string input from the first encoding unit 1140.

And a compressed identification information symbol string input from the second encoder 1150.

Packing to generate an information packet Z.

17 illustrates a control flow for data compression in the compression apparatus according to the second embodiment of the present invention.

Referring to FIG. 17, in operation 1710, the compression apparatus receives a binary information bit string from an external source. Thereafter, the compression apparatus extracts the hidden information string from the input binary information bit string in step 1712, and extracts the hidden information string from the remaining binary information bit string after extracting the hidden information string in step 1714. . At this time, the count value n for counting the number of information concealment is set to 0.

In operation 1716, the compression apparatus hides the extracted hidden information sequence from the extracted hidden information sequence to generate a m-information symbol sequence. In this case, m is a constant representing the essence of the generated information symbol string, which corresponds to n, which is a hidden count count value, plus two. That is, each time information hiding is performed, the number of generated information symbol strings is increased by one.

In operation 1718, the compression apparatus determines whether the integer of the previously generated information symbol string is a desired number. That is, since the information concealment has been performed so far, the compression apparatus will determine that the desired decimal number is 3 when the order of the information symbol string to be finally obtained is three. However, if it is desired to obtain an information symbol string having more orders, the compression apparatus proceeds to step 1720 and increases n by one and returns to step 1714.

Upon returning to step 1714, the compression apparatus extracts a new hidden information string from the remaining binary information bit streams excluding the previously hidden hidden information string and the hidden information string. In addition, the newly extracted concealment information is further concealed to the previously generated information symbol string, thereby generating an information symbol string having an increased one.

When the compression apparatus determines that the desired information symbol string is obtained in step 1718, the compression apparatus proceeds to step 1722 to generate a binary data information symbol string and an identification information symbol string from the obtained information symbol string. In operation 1724, the compression apparatus encodes each of the binary data information symbol string and the identification information symbol string. In this case, encoding may be performed by an entropy compression technique. The entropy compression technique may use any of Huffman code or arithmetic code coder, as described above.

In operation 1726, the compression device generates an information packet through packing of the information symbol string compressed through encoding.

B. Restoration Technique

In the following description, various embodiments of a technique of recovering the hidden symbol and the hidden symbol from the information hiding symbol having a predetermined value among the information hiding symbols constituting the m information hidden symbol string will be described in detail. The predetermined value may be a minimum value and a maximum value that the information hiding symbol may have.

B-1. First Embodiment (Restore Technology)

18 shows a configuration of a restoration apparatus according to the first embodiment of the present invention.

Referring to FIG. 18, the decoding unit 1810 receives an information packet Z to be restored and inputs the information packet Z to be restored by a predetermined decoding technique.

Outputs

As an example, an entropy decoding technique corresponding to an entropy coding technique may be applied to the decoder 1810.

The first switch S / W # 1 is a m-information symbol string output from the decoder 1810.

Is transmitted to the information restoring unit 1820 or the information symbol string from which information concealed from the information restoring unit 1820 is extracted.

Performs an operation for feeding back to the information recovery unit 1820.

That is, the first switch (S / W # 1) is a m-information symbol string output from the decoder 1810

Is transmitted to the input of the information recovery unit 1820 and the information symbol string from which the hidden information output from the information recovery unit 1820 is extracted

To form a path for delivering the information to the input of the information recovery unit 1820.

At this time, the information symbol string in which information concealment transmitted from the decoder 1810 is performed.

N denotes the number of times information concealment has been made. M is an order of the information symbol string finally obtained through information concealment, and may be defined as n + 2. For example, if information concealment has been performed once (n = 1), m is 3.

The second switch S / W # 2 is an information symbol string from which the hidden information output from the information recovery unit 1820 is extracted.

To the input of the bit combiner 1830 or to the input of the information recovery unit 1820 through the first switch (S / W # 1).

Operation of the first switch (S / W # 1) and the second switch (S / W # 2) related to the number of information concealment for information recovery according to an embodiment of the present invention can be summarized as shown in Table 2 below. Can be.

TABLE 2

In Table 2, the off state of S / W # 1 is a state in which a path for inputting the output of the decoder 1810 to the information restoring unit 1820 is formed, and the on state of S / W # 1 is information restoration. A path for inputting the output of the unit 1820 to the information recovery unit 1820 is formed. In Table 2, the off state of S / W # 2 is a state in which a path for inputting the output of the information restoring unit 1820 to the bit combiner 1830 is formed, and the on state of S / W # 2 is A path for transmitting the output of the information recovery unit 1820 to the S / W # 1 is formed.

However, the operation of the S / W # 1 and the S / W # 2 is not limited to the above-described and should not be interpreted. That is, even if the operations of the S / W # 1 and the S / W # 2 performs the opposite operation as described above, it is apparent to those skilled in the art that there is no difficulty in implementing the embodiment of the present invention.

On the other hand, the control of the S / W # 1 and the S / W # 2 may be made by a configuration for controlling the overall operation of the equipment having a switching controller or compression device provided separately.

In addition, in Table 2, the input refers to a sequence of information symbols input to the information recovery unit 1820 through S / W # 1, and in Table 2, the output is input to the bit combiner 1830. Means a hidden information string and a hidden information string.

The information recovery unit 1820 is an information symbol string in which information concealment is performed

Is an input, and the information symbol string in which the input information concealment is performed

From PB to PEN

or

And concealed information columns

or

Restore The information restoration by the information restoration unit 1820 is an information symbol string in which information concealment is performed.

Is performed repeatedly until n goes to zero. In other words, the information restored by the information recovery unit 1820 is repeatedly performed until the true number of the hidden information string is binary. In this case, n decreases by one every time information restoration is performed.

The information recovery unit 1820 is an information symbol string in which information concealment is performed

One hidden input column from

And at least one hidden information column

or

Perform an operation to restore the.

20 to 26 show examples for restoring information according to a restoration technique proposed by an embodiment of the present invention. 20 to 22 show an example for restoring the hidden hidden information string U and the hidden information string V from the binary information symbol string L. FIG. 23 and 25, the hidden information string of the ternary number from the information symbol string of the ternary number is shown.

Hidden information columns in binary and binary

24 and 26 show a hidden hidden information string from a binary information symbol string.

Hidden information columns in binary and binary

An example for restoring

20 to 22, it may be assumed that information concealment is performed when the symbol value is 0 in the information symbol string L and when the symbol value is 1 and the symbol identification information M is 1. FIG.

23 to 26, the information concealment is an information symbol string in which the information concealment is performed.

It can be assumed that in the case where the symbol value is 0 and the symbol value corresponds to the highest order. That is, in FIG. 23 and FIG. 25, the information symbol string in which the information is concealed

In the case where the symbol value is 0 and the symbol value is 3, the information concealment is performed. In addition, in FIG. 24 and FIG. 26, an information symbol string in which information concealment is performed.

In the case where the symbol value is 0 and the symbol value is 2, information concealment is performed.

Since it is judged that information concealment has not been performed for symbols having other symbol values, the hidden information column is used as it is.

Restore the corresponding symbol value of. That is, in FIG. 23 and FIG. 25, the information symbol string in which the information is concealed

In the case where the symbol value is 1 and the symbol value is 2, information concealment is not achieved. In addition, in FIG. 24 and FIG. 26, an information symbol string in which information concealment is performed.

In the case where the symbol value is 1, the information concealment may not be performed.

First, referring to FIGS. 20 to 22, for the first, second, and fifth to ninth symbols having a symbol value of 0 in the information symbol string L, values of the corresponding hidden symbol and the hidden symbol are restored to zero. However, since the last symbol of the information symbol string L is 0 but the flag information F is 1, only the tenth symbol value of the hidden information string V is restored to zero. If the flag information F is 0, as shown in FIG. 21, the value of the corresponding hidden symbol and the hidden symbol are all restored to zero. As another example, as shown in FIG. 22, when the flag information F is 1, only the last symbol value of the hidden information string V is restored to 1 even if the value of the last symbol of the information symbol string L is 1.

Meanwhile, the third, fourth, and tenth symbols having the symbol value 1 in the information symbol string L are restored in consideration of the value of the symbol identification information M. FIG. For example, when the symbol value is 1 and the value of the symbol identification information M is 0 like the third symbol in the information symbol string L, only the corresponding hidden symbol (the third symbol in the hidden information column) is restored to 1. However, if the symbol value is 1 and the symbol identification information M has a value of 1, as in the fourth and tenth symbols in the information symbol column L, the corresponding hidden symbol (fourth and tenth symbols in the hidden information column) is zero. Restore the corresponding hidden symbols (third and ninth symbols in the hidden information column) to one.

Referring to FIG. 23, an information symbol string in which information concealment is performed

The symbol values are sequentially read from the highest symbol to the lowest symbol. If the read symbol value is 0, the hidden information column

Corresponding symbol values and hidden information columns in

Set the corresponding symbol value of to 0. If the read symbol value is 3, the hidden information column

Set the value of the corresponding symbol in to 0, and the hidden information column

Set the corresponding symbol value of to 1. However, if the read symbol value is 1, the hidden information column

Set only the corresponding symbol value of to 1, and if the read symbol value is 2, the hidden information column

Set only the relevant symbol value of to 2.

An information symbol string in which the information concealment is performed

Since the first symbol value in is 3, the hidden information column

Set the first symbol value of to 0 and conceal information column

Set the first symbol value of to 1.

An information symbol string in which the information concealment is performed

Since the second symbol value in is 1, the hidden information column

Set only the second symbol value to 1. An information symbol string in which the information concealment is performed

Since the third to sixth symbol values in all are zero, the hidden information column

Set the third to sixth symbol values of 0 to a hidden information column

Set the second to fifth symbol values of 0 to zero.

Finally, the information symbol string in which the information concealment is made

Since the seventh symbol value of is 2, the hidden information column

Set only the seventh symbol value of to 2.

Information symbol string in which information concealment is performed as can be seen in the above example

If the symbol value of is 0, the hidden information column

A column of hidden information corresponding to the symbol's value of 0

It can be seen that the symbol value of 0 is hidden. And information symbol string with information concealment

If the symbol value of is 3, the hidden information column

A column of hidden information corresponding to the symbol's value of 0

It can be seen that the symbol value of 1 is hidden. Hidden information column

Hidden information column when the symbol value of is 0

The symbol value of is concealed and the hidden information column

If the symbol value of is not 0, the information symbol column whose information is concealed

It can be seen that it remains intact.

Therefore, the hidden information column restored by the above-mentioned.

The order of the symbols constituting the symbol is ternary.

Next, referring to FIG. 24, an information symbol string in which information concealment is performed

The symbol values are sequentially read from the highest symbol to the lowest symbol. If the read symbol value is 0, the hidden information column

Corresponding symbol values and hidden information columns in

Set the corresponding symbol value of to 0. If the read symbol value is 2, the hidden information column

Set the value of the corresponding symbol in to 0, and the hidden information column

Set the corresponding symbol value of to 1. However, if the read symbol value is 1, the hidden information column

Set only the relevant symbol value of to 1.

An information symbol string in which the information concealment is performed

Since the first symbol value and the third through sixth symbol values of 0 are zero, the hidden information column

Set the first symbol value and the third to sixth symbol values of 0 to a hidden information column

Set the first symbol value of and the second through fifth symbol values to zero. And an information symbol string in which the information concealment is performed.

Since the second symbol value in is 1, the hidden information column

Set only the second symbol value to 1.

Finally, the information symbol string in which the information concealment is made Since the seventh symbol value of is 2, the hidden information column

Set the seventh symbol value of to 0 and conceal information column

Set the sixth symbol value of to 1.

Information symbol string in which information concealment is performed as can be seen in the above example

If the symbol value of is 0, the hidden information column

A column of hidden information corresponding to the symbol's value of 0

It can be seen that the symbol value of 0 is hidden. Hidden information column

Hidden information column when the symbol value of is 0

The symbol value of is concealed and the hidden information column

If the symbol value of is not 0, the information symbol column whose information is concealed

It can be seen that it remains intact.

Therefore, the hidden information column restored by the above-mentioned.

The order of the symbols constituting the symbol is binary.

Meanwhile, in the example illustrated in FIGS. 25 and 26, detailed information will be omitted as information restoration is performed in the same manner as described above with reference to FIGS. 23 and 24. Only in FIG. 25 and FIG. 26, the information symbol sequence in which information hiding used in FIGS. 23 and 24 is performed.

Information symbol strings with different information concealment than

There is only a difference that is used.

As described above, the binary hidden information string output from the information restoring unit 1820.

And at least one concealed information column

or

,

Is input to the bit coupling unit 1230 through the second switch (S / W # 2).

The bit combiner 1830 is a hidden information string

And at least one concealed information column

or

,

(n≥1) is input, and the hidden information string

And at least one concealed information column

or

,

(n≥1) is combined to output the information bit string X.

27 and 28 are hidden information columns according to an embodiment of the present invention.

And at least one concealed information column

or

,

Examples of combining (n≥1) to generate a binary information bit string are shown. 27, the hidden information column

And at least one concealed information column

or

,

(n≥1) is shown in the example of successive combinations, and in FIG. 28, the hidden information column

And at least one concealed information column

or

,

An example of combining (n≥1) in parallel is shown.

First, referring to FIG. 27, an input hidden information column

Is output as the predetermined number of bits from the most significant bit (MSB) of the information column X. And the hidden information column

Hidden Information Columns Consecutively Entered into

, And other hidden information columns

The hidden information column is entered

Output continuously.

On the other hand, if there is additionally input hidden information string can be output continuously to the last output hidden information string.

Referring next to FIG. 28, the hidden information column

And concealed information columns

Wow

Combine by symbol order. However, if the symbol value checked for join is 1, the hidden information column

Return to and perform the join from the next symbol.

Hidden information column

Since the first symbol value of is 0, the first bit value of the binary information bit string X is 0, and the hidden information column

Since the first symbol value of is 1, the second bit value of the binary information bit string X is 1.

After that, in principle, the hidden information column

The first symbol value of 0 must be set as the third bit value of the binary information bit string. But in front of the hidden information column

The hidden information column because the value of the first symbol in was 1

Hidden information column other than the first symbol value in

Set 0, the second symbol value of, to the third bit value of the binary information bit string X.

The fourth bit value and the second bit value of the binary information bit string X are set to 0 according to the basic combining principle. However, the hidden information column identified for setting the third bit value of the column of the binary information bit string X

Since the fifth symbol value of is 1, the column third bit value of the binary information bit string X is set to one. Then the hidden information column

Hidden information column other than the fourth symbol value

Set 1, the sixth symbol of, to the fourth bit of the column of the binary information bit string X. As well as the hidden information column

Since the sixth symbol value of was also 1, the hidden information column

Set 0, the seventh symbol value of, to the fifteenth bit value of the binary information bit string X.

In FIG. 28, two hidden information columns are assumed, but the same applies to a case where more hidden information columns are combined. Also the first hidden information column

And the first hidden information column

And second hidden information columns

The total number of bits of the binary information bit string to be generated by combining may be determined in advance as needed. Only the first hidden information column in determining the total number of bits

It may be desirable to consider the number of bits and the distribution of bits having a value of 1 or the number of bits having a bit value of 0 and the like.

19 shows a control flow for data restoration in a restoration apparatus corresponding to a compression apparatus according to the first embodiment of the present invention.

Referring to FIG. 19, in operation 1910, the decompression device decodes an m-information symbol string input from the outside. In this case, the decoding may be performed by a reconstruction technique corresponding to the entropy compression technique. The entropy compression technique may use any of Huffman code or arithmetic code coder, as described above.

The decompression device performs decompression of the m-decoded information symbol string previously decoded in step 1912. That is, the hidden hidden information string is extracted from the m-th information string. The decompression device may obtain an information symbol string having a decimal number that is reduced by one compared to the m information symbol string due to the extraction of the hidden information string. For example, if the true number of the information symbol string before information restoration is 4, the order of the information symbol string (or hidden information string) obtained after the information restoration is three.

The decompression device outputs the hidden information string extracted in step 1914, and determines whether the true number of the hidden information string obtained in step 1916, that is, the information symbol string after the hidden information string is extracted, is a desired number. That is, it is determined whether the binary number of the hidden information string obtained earlier is a binary number.

If the previously hidden information sequence has more orders, the recovery apparatus proceeds to step 1918 and decreases n by 1 and returns to step 1912.

Upon returning to step 1912, the decompression device performs an information restoration operation for extracting a new hidden information string from the previously concealed hidden information string. By extracting the new hidden information string, the number of obtained hidden information strings is reduced by one.

If the acquisition of the desired hidden information string of the real number is made by the above-described operation, the restoration apparatus obtains the hidden hidden information string of the binary number finally obtained in step 1920.

Extract

In operation 1922, the decompression device combines the extracted hidden information string with at least one hidden information string to generate a final binary information bit string.

B-2. Second Embodiment (Restore Technology)

29 is a block diagram of a decompression device corresponding to a compression device according to a second embodiment of the present invention. Reference numerals 2950 and 2960 and the first and second switches 2950, 2960, and the first and second switches of FIG. 29 perform the same operations as those of the first and second switches of FIG. 18. In FIG. 29, the first and second decoding units corresponding to the reference numerals 2920 and 2930 differ only in the input data, and perform the same operations as the decoding unit corresponding to the reference numeral 1810 in FIG. 18.

Therefore, it should be noted that the detailed description of the configuration is omitted in the operation description according to the second embodiment of the present invention to be described later.

Referring to FIG. 29, the information depacking unit 2910 receives an input information packet Z and depacks the input information packet Z to compress a data information symbol string.

And compressed identification symbol columns

Outputs The compressed data information symbol string

Is input to the first decoding unit 2920, and the compressed identification information symbol string

Is input to the second decoding unit 2930.

The first decoder 2920 is a compressed data information symbol string

Is input, and the compressed data information symbol string

The data information symbol string is recovered by decoding by a decoding technique corresponding to a predetermined coding scheme.

Outputs

The second decoding unit 2930 is a compressed identification information symbol string

Is input, and the compressed identification information symbol string

Reconstructs the identification information symbol string by a decoding scheme corresponding to a predetermined coding scheme.

Outputs

30 is a block diagram of a decoder constituting a decompression device according to a second embodiment of the present invention. The decoding unit shown in FIG. 30 is a compressed data information symbol string

It is assumed that the first decoding unit 2920 takes as an input. But compressed identity symbol columns

It is apparent that the configuration of FIG. 30 may be equally applied to the second decoding unit 2930 having the input as.

Referring to FIG. 30, the compressed data information symbol column

Is input to the entropy decoder 3010. The entropy decoder 3010 is a compressed data information symbol string

Is input, and the compressed data information symbol string

Is a column of data information symbols in hexadecimal or octal number by a decoding technique corresponding to the entropy coding technique.

Is restored. A quaternary or octal number of data information symbol string restored by the entropy decoder 3010

Is passed to the decimal converter 3020.

The hexadecimal converter 3020 is a data information symbol string of a hexadecimal number or an octal number.

Inputs the data information symbol string of the input hexadecimal or octal number

Column of data information symbols in binary

Convert to That is, the input data information symbol string

Since hexadecimal has a hexadecimal number or more, the hexadecimal converter 3020 includes a data information symbol string having a binary number.

Outputs

31 and 32 illustrate an example of converting a hexadecimal number from a hexadecimal converter in a decoder constituting a decompression device according to a second embodiment of the present invention. That is, in Fig. 31, the data information symbol string of the ternary number

Column of data information symbols in binary

In FIG. 32, an octal data information symbol string is shown.

Column of data information symbols in binary

An example of converting to is shown.

First, referring to FIG. 31, a data information symbol string of a hexadecimal number is used.

Select the hexadecimal symbols constituting the sequence sequentially, and convert each of the hexadecimal symbols sequentially selected to binary. In other words, one hexadecimal symbol is converted into a binary symbol consisting of two symbol sets.

More specifically, the data information symbol column of the hexadecimal number

Since the first symbol value in is 2, the data information symbol column in binary

Set the first and second symbols of to 10.

And the data information symbol string of the hexadecimal number.

Since the second and third symbol values of 0 are zero, the data information symbol column of the binary number

Set the third and fourth symbols and the fifth and sixth symbols of 00 to 00.

The data information symbol string of the hexadecimal number

Since the fourth symbol value of is 1, the binary data information symbol string

Set the seventh and eighth symbols of 01 to 01. In addition, the data information symbol string of the hexadecimal number

Since the fifth symbol value of is 3, the binary data information symbol string

Set the ninth and tenth symbols of to 11.

As described above, the quaternary data information symbol string

A string of binary data information symbols as the result of the hexadecimal conversion for "1000000111000110".

Can be generated.

Next, referring to FIG. 32, an octal data information symbol string

Select the octal symbols constituting the sequence sequentially, and convert each of the sequentially selected octal symbols to binary. In other words, one octal symbol is converted into a binary symbol consisting of three symbol sets.

More specifically, the data information symbol column in octal

Since the first and fourth symbol values in are 4, the data information symbol column in binary

Set the first through third symbols and the tenth through tenth symbols of to 100.

And the data information symbol string of the octal number.

Since the second and sixth symbol values of 0 are 0, the data information symbol column of the binary number

Set the fourth through sixth symbols and the sixteenth through eighteenth symbols of to 000.

The octal data information symbol string

Since the third and fifth symbol values of 3 are 3, the binary data information symbol column

Set the seventh through ninth symbols and the thirteenth through fifteenth symbols of 011.

As described above, the octal data information symbol string

A string of binary data information symbols as the result of the hexadecimal conversion for "100000011100011000".

Can be generated.

As described above, the binary data information symbol string decoded by the first decoding unit 2920.

And a binary identification information symbol string decoded by the second decoding unit 2930

Is input to the m evolution unit 2940.

Where the data information symbol string

Is a binary information symbol column

Binary information symbol string for distinguishing each symbol of 0 or not. And the identification information symbol string

Is the data information symbol column

When a specific symbol is not 0, the binary information symbol string has information for identifying the value of the symbol.

The m-evolution unit 2940 is a binary data information symbol string input from the first decoding unit 2920 and the second decoding unit 2930.

Information symbol columns in binary and binary

M information symbol string through m-evolution using

Outputs

33 and 34 show an example of the m-evolution operation in the decompression device according to the second embodiment of the present invention. That is, in Fig. 33, a binary data information symbol string

Information symbol columns in binary and binary

Symbolic column of digits from

Shows an example of generating a data stream, and in FIG. 34, a binary data information symbol string is shown.

Information symbol columns in binary and binary

Symbolic information column from hexadecimal

Shows an example of creating a.

The m-evolution operation shown in FIGS. 33 and 34 is a binary data information symbol string.

If the symbol value existing at a specific position is 0, the corresponding symbol value of the m information string is set to 0. But the binary data information symbol string

If the symbol value existing at a specific position of 1 is 1, the identification information symbol string of binary corresponding to the symbol whose value is 1

Check the value of the symbol. And the identification information symbol string of the identified binary number.

Consider the symbol value of and set the corresponding symbol value of m information string.

Where the identification information symbol string of the binary number

Considering the symbol value of, the symbol value to be set to the corresponding symbol value of the information symbol string of the m number is a previously promised value.

For example, if m is 3, the identification symbol column of the binary number checked

If the symbol value of is 0, the information symbol column of the ternary number

Set the corresponding symbol value of to 1. However, the identification information symbol string of the identified binary number

Information symbol column in ternary if symbol value of 1 is 1

Set the corresponding symbol value of to 2.

In other words, when m is 2, the binary identification information symbol string

Information symbol column in ternary if the symbol value of is 0

Set the corresponding symbol value of to 1, and identify the symbolic column of binary

Column of information symbols in ternary if symbol value of 1 is 1

Corresponds to the prior commitment to set the corresponding symbol value to 2.

However, assuming that m is 4, the identification symbol column of the identified binary number

If the symbol value of is 0, the information symbol column in hexadecimal

Set the corresponding symbol value of to 1. However, the identification information symbol string of the identified binary number

If the symbol value of is 10, the information symbol column in hexadecimal

The corresponding symbol value of is set to 2, and the identification information symbol column of the checked binary number

If the symbol value of is 11, the information symbol column in hexadecimal

Set the corresponding symbol value of to 3.

In other words, when m is 4, a binary identification information symbol column

Information symbol column in hexadecimal if symbol value of is 0

Set the corresponding symbol value of to 1, and identify the symbolic column of binary

Information symbol column in hexadecimal if symbol value of is 10

Sets the corresponding symbol value of to 2, and identifies the symbolic column of binary

Information symbol column in hexadecimal if the symbol value of is 11

Corresponds to the prior appointment to set the corresponding symbol value to 3.

Referring first to FIG. 33, a data information symbol column

Read the first symbol value of. At this time, the data information symbol string

Information symbol column in ternary because the first symbol value in is 0

The first symbol value of is set to zero. In this case, an identity information symbol column

There is no symbol to use.

Then the data information symbol string

Read the second symbol value. At this time, the data information symbol string

The identity symbol column because the value of the second symbol in is not zero

Check the first symbol value of. Where the identification information symbol string

The reason for checking the value of the first symbol in is the data information symbol column

This is because the first symbol value of 1 has occurred. The identified identification information symbol string

Since the first symbol value of is 0, the information symbol column

The second symbol value of is set to 1.

The data information symbol string

Since the third to sixth symbol values of all are 0, the information symbol column

The third through sixth symbol values of are all set to zero. In this case, the identification information symbol string

There is no symbol to use.

Finally the data information symbol string

Read the seventh symbol value. At this time, the data information symbol string

The seventh symbol value in is not zero, so the identity symbol column

Check the value of the second symbol in. Where the identification information symbol string

Reason for checking the value of the second symbol in the Data Information Symbol column

This is because the second symbol case has a value of 1 from. The identified identification information symbol string

Since the first symbol value of is 1, the information symbol column

The seventh symbol value of is set to 2.

Thus, the final generated hexadecimal column of information symbols

The furnace generates “0100002”.

Referring next to FIG. 34, a data information symbol column

Read the first symbol value of. At this time, the data information symbol string

Identity symbol column because the first symbol value in the is not zero

Check the first symbol value of. Where the identification information symbol string

The reason for checking the value of the first symbol in is the data information symbol column

This is because the first symbol value of 1 has occurred. The identified identification information symbol string

Since the first symbol value of is 11, the information symbol column

The first symbol value of is set to 3.

The data information symbol string

Read the second symbol value. At this time, the data information symbol string

The identity symbol column because the value of the second symbol in is not zero

Check the value of the second symbol in. Where the identification information symbol string

Reason for checking the value of the second symbol in the Data Information Symbol column

This is because the second symbol case has a value of 1 from. The identified identification information symbol string

Since the second symbol value of is 0, the information symbol column

The second symbol value of is set to 1.

The data information symbol string

Since the third to sixth symbol values of all are 0, the information symbol column

The third through sixth symbol values of are all set to zero. In this case, the identification information symbol string

There is no symbol to use.

Finally the data information symbol string

Read the seventh symbol value. At this time, the data information symbol string

The seventh symbol value in is not zero, so the identity symbol column

Check the third symbol value of. Where the identification information symbol string

The reason for checking the value of the third symbol in the Data Information Symbol column

This is because the third occurrence of a symbol value from 1 occurs. The identified identification information symbol string

Since the third symbol value of is 10, the information symbol column

The seventh symbol value of is set to 2.

Thus, the final generated hexadecimal column of information symbols

The furnace produces “3100002”.

The information symbol string of the m-number generated by the m-evolution unit 2940 is transferred to the information recovery unit 2950 through the first switch S / W # 1. Since the operation by the subsequent configuration is the same as the operation in the restoration apparatus according to the first embodiment of the present invention, a detailed description thereof will be omitted.

35 illustrates a control flow for data restoration in a restoration apparatus corresponding to a compression apparatus according to a second embodiment of the present invention.

Referring to FIG. 35, in operation 3510, the decompression device depacks an information packet input from the outside and outputs a data information symbol string and an identification information symbol string. In operation 3512, the decompression device decodes each of the data information symbol string and the identification information symbol string to output a binary data information symbol string and an identification information symbol string. In this case, the decoding may be performed by a reconstruction technique corresponding to the entropy compression technique.

In operation 3514, the decompression device generates an m-number information symbol string using a binary data information symbol string and an identification information symbol string output through the decoding operation.

In operation 3516, the decompression device restores the m-information symbol string previously generated. That is, the hidden hidden information string is extracted from the m-th information string. The decompression device may obtain an information symbol string having a decimal number that is reduced by one compared to the m information symbol string due to the extraction of the hidden information string. For example, if the true number of the information symbol string before information restoration is 4, the order of the information symbol string (or hidden information string) obtained after the information restoration is three.

In step 3518, the decompression device extracts the hidden information string by restoring the information, and outputs the extracted hidden information string. In operation 3520, the decompression device determines whether the true number of the hidden information string, that is, the information symbol string after the hidden information string has been extracted, is a desired number. That is, it is determined whether the binary number of the hidden information string obtained earlier is a binary number.

If the previously obtained hidden information sequence has more orders, the recovery apparatus proceeds to step 3522 and decreases n by 1 and returns to step 3516.

When it is returned to step 3516, the restoration apparatus performs an information restoration operation for extracting a new hidden information sequence from the previously concealed hidden information sequence. By extracting the new hidden information string, the number of obtained hidden information strings is reduced by one.

If the acquisition of the desired hidden information string of the decimal number is obtained by the above-described operation, the restoration apparatus obtains the hidden hidden information string of the binary number finally obtained in step 3524.

Extract

In operation 3526, the decompression device combines the extracted hidden information string and the extracted at least one hidden information string to generate a final binary information bit string.

On the other hand, while the preferred embodiment of the present invention has been shown and described, the present invention is not limited to the specific embodiments described above, in the technical field to which the invention belongs without departing from the spirit of the invention claimed in the claims Various modifications can be made by those skilled in the art, and these modifications should not be individually understood from the technical spirit or the prospect of the present invention.

For example, in the first and second embodiments of the present invention, the compression apparatus is described as implemented by a plurality of configurations. However, this is for convenience of description, and the compression technique according to the first and second embodiments of the present invention may be implemented by one configuration capable of digital signal processing. That is, it may be implemented by a digital signal processor (DSP). However, even if the compression technique according to the embodiment of the present invention is implemented through one digital signal processing apparatus such as a DSP, specific operations for compression are the same.

In addition, it is possible to implement a decompression device corresponding to the compression device according to the first and second embodiments of the present invention by using a digital signal processing device such as a DSP.

In the compression apparatuses according to the first and second embodiments of the present invention, the first input information is limited to the case of binary numbers. However, even if the input information has more digits, it is obvious that the compression technique proposed in the first and second embodiments of the present invention can be equally applied.

For example, when the input information is a ternary number, the first and second embodiments of the present invention may be applied in the same manner as the operation of compressing the data once compressed through additional information concealment.

If only the first number of information bits is binary or more, the hidden information bit value may have a value other than 0 and 1, so that the order of increase by one information concealment may vary. For example, when ternary information is input, the order of the information symbol string obtained by the first information concealment will be a decimal number.

Generalizing this, assuming that the number of input information bits is n, the order of increment by one information concealment is n-1. Therefore, the order of the bit string outputted by the first information concealment by inputting the n-decimal number is n + (n-1).

In addition, in the embodiment of the present invention, it is assumed that the hidden information bit is concealed for a bit having a hidden information bit value of zero. This case is more effective when the number of bits having a value of 0 in the bit values constituting the hidden information bit string is relatively large compared to the number of bits having a value of 1.

However, according to another embodiment of the present invention, when the number of bits having a value of 1 in the bit value constituting the hidden information bit string is relatively large compared to the number of bits having a value of 0, the bit having the hidden information bit value is 1 It may be more efficient to conceal the concealed information bits for. In this case only, the number of bits of the hidden information bits should be determined in consideration of the number of bits having a value of 1 constituting the hidden information string. That is, the operation according to another embodiment of the present invention proposed above is the same as the operation according to the embodiment of the present invention, but has only a difference in the used bit value.

Claims (28)

1. In the apparatus for compressing data, a target hidden symbol to be concealed for a target hidden symbol having a predetermined value among the hidden hidden symbols is determined from the hidden symbols, and corresponds to a combination of the target hidden symbol and the target hidden symbol. And an information concealment unit which substitutes a value of the target hidden symbol with a symbol value.
2. The data compression apparatus of claim 1, wherein a symbol value corresponding to a combination of the target hidden symbol and the target hidden symbol has a decimal value higher than the base number of the hidden symbols and the hidden hidden symbol.
3. 3. The method of claim 2, wherein the true number of the hidden symbols is m, the true number of the hidden symbols is binary, and the predetermined value is 0, corresponding to a combination of the target hidden symbol and the target hidden symbol. Data compression device characterized in that the symbol value is 0 or m.
4. 5. The method of claim 3, wherein the information hiding unit determines that a symbol value corresponding to a combination of the target hidden symbol and the target hidden symbol is 0 when the value of the target hidden symbol is 0, and determines the value of the target hidden symbol. Is 1, the symbol value corresponding to the combination of the target hidden symbol and the target hidden symbol is determined as m.
5. The method of claim 1, wherein a symbol value corresponding to the combination of the target hidden symbol and the target hidden symbol is a value of the target hidden symbol, and the information hiding unit corresponds to a combination of the target hidden symbol and the target hidden symbol. And a flag value for identifying whether the information for identifying a symbol value and the number of hidden symbols match the number of hidden symbols.
6. The data compression according to any one of claims 1 to 5, further comprising a separator for separating a hidden symbol string composed of the hidden symbols and a hidden symbol string composed of the hidden symbols from an information string to be compressed. Device.
7. The data compression apparatus according to any one of claims 1 to 5, further comprising an entropy encoder for encoding the information concealment symbol string generated by the information concealment unit.
8. The binarization unit according to any one of claims 1 to 4, wherein the binarization unit converts the information concealment symbol sequence generated by the information concealment unit into a binary data information symbol sequence and a binary identification information symbol sequence, and the binary data information. An hexadecimal converter for converting a symbol string and the binary identification information symbol string into a hexadecimal or octal data information symbol string and an identification information symbol string, and an entropy encoder for encoding each of the hexadecimal or octal data information symbol string and the identification information symbol string. Data compression device further comprising.
9. In the data compression method, Determining a target hidden symbol to be hidden for the target hidden symbol having a predetermined value among the hidden symbols from the hidden symbols, Combination of the target hidden symbol and the target hidden symbol And substituting the value of the target hidden symbol with a symbol value corresponding to.
10. The data compression method of claim 9, wherein a symbol value corresponding to a combination of the target hidden symbol and the target hidden symbol has a decimal value higher than the base number of the hidden symbols and the hidden hidden symbol.
11. 11. The method of claim 10, wherein if the true number of the hidden symbols is m, the true number of the hidden symbols is binary, and the predetermined value is 0, the combination of the target hidden symbol and the target hidden symbol corresponds to a combination thereof. Method of compressing data, characterized in that the symbol value is 0 or m.
12. The method of claim 11, wherein the substituting includes determining a symbol value corresponding to a combination of the target hidden symbol and the target hidden symbol as 0 when the value of the target hidden symbol is 0, and determining the value of the target hidden symbol. And when the value is 1, determining a symbol value corresponding to a combination of the target hidden symbol and the target hidden symbol as m.
13. 10. The method of claim 9, wherein information for identifying a symbol value corresponding to a combination of the target hidden symbol and the target hidden symbol and a flag value for identifying whether the number of the hidden symbols and the number of the hidden symbols match. The method may further include generating a data, wherein a symbol value corresponding to the combination of the target hidden symbol and the target hidden symbol is a value of the target hidden symbol.
14. The data compression method according to any one of claims 9 to 13, further comprising: separating a hidden symbol string composed of the hidden symbols and a hidden symbol string composed of the hidden symbols from an information string to be compressed. Way.
15. The data compression method according to any one of claims 9 to 13, further comprising entropy encoding the information concealment symbol sequence generated during the substitution.
16. The method of claim 9, further comprising converting the information concealment symbol sequence generated by the substituting process into a binary data information symbol sequence and a binary identification information symbol sequence, and the binary data information symbol. Converting a column and the binary identification information symbol string into a hexadecimal or octal data information symbol string and an identification information symbol string, and entropy encoding each of the hexadecimal or octal data information symbol string and the identification information symbol string. Data compression method.
17. An apparatus for restoring a data, comprising: an information restoration unit for restoring a hidden symbol and a hidden symbol from an information hidden symbol having a predetermined value among information hidden symbols constituting a m-coded information hidden symbol string, wherein the predetermined value is And a minimum value and a maximum value of the information concealment symbol.
18. The method of claim 17, wherein the information reconstruction unit restores the hidden symbol and the hidden symbol to 0 when the predetermined value is 0 which is the minimum value that the information hidden symbol can have, and the predetermined value is the information. And m, which is the maximum value that a hidden symbol can have, restoring the hidden symbol to zero and restoring the hidden symbol to one.
19. The method of claim 17, wherein the information reconstruction unit restores the information hiding symbol having the highest value to the hidden symbol only by the information for identifying the information hiding symbol having the highest value into the hidden symbol and the hidden symbol. Determine whether to recover the last information hidden symbol constituting the information hidden symbol string only as a hidden symbol by a flag value identifying whether the number of hidden symbols to be recovered from the information hidden symbol string matches the number of hidden symbols. A data recovery device for determining whether to recover a hidden symbol or a hidden symbol.
20. The method according to any one of claims 17 to 19, wherein the information reconstruction unit reconstructs the information concealment symbol, which is not a predetermined value, among the information concealment symbols constituting the m-coded information concealment symbol sequence only as the hidden symbol. A data recovery device characterized by the above-mentioned.
21. The data restoration apparatus according to any one of claims 17 to 19, further comprising a combiner configured to combine the hidden symbol string and the hidden symbol string restored by the information recovery unit, and output the combined symbol string as one information string.
22. 20. The data recovery apparatus of claim 17, further comprising a decoder configured to decode the compressed data by a decoding technique corresponding to an entropy coding technique, and to output the m information hidden symbol string.
23. A method for restoring a data, the method comprising: restoring a hidden symbol and a hidden symbol from an information hidden symbol having a predetermined value among the information hidden symbols constituting the m information hidden symbol string, wherein the predetermined value is A method for restoring data, characterized in that the minimum and maximum values an information concealment symbol can have.
24. The method of claim 23, wherein the restoring comprises: restoring the hidden symbol and the hidden symbol to zero when the predetermined value is 0, which is the minimum value of the information hidden symbol, and the predetermined value. Restoring the hidden symbol to 0 and restoring the hidden symbol to 1 when m is the maximum value of the information concealment symbol.
25. The method of claim 23, wherein the reconstructing comprises: restoring the information hiding symbol having the highest value to the hidden symbol only by the information for identifying the information hiding symbol having the highest value. And deciding whether to reconstruct the last information hidden symbol constituting the information hidden symbol string by a flag value identifying whether the number of hidden symbols to be restored and the number of hidden symbols match from the information hidden symbol string. A method for restoring data comprising determining whether to restore only to a hidden symbol or a hidden symbol.
26. The method of claim 23, wherein the reconstructing comprises: restoring only the hidden information symbol, which is not a predetermined value, among the information hiding symbols constituting the m-th information hidden symbol string. Data restoration method further comprising the process.
27. 26. The method of any one of claims 23 to 25, further comprising combining the hidden symbol string restored by the restoring process with the hidden symbol string and outputting them as one information string.
28. 26. The method of any one of claims 23 to 25, further comprising decoding the compressed data by a decoding technique corresponding to an entropy coding technique and outputting the m-information hidden symbol string.

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