KR20070042489A - Decoding device and method for analyzing syntax to decode bit-stream - Google Patents

Abstract

Disclosed are a decoding apparatus and a syntax analysis method for bitstream decoding. A decoder according to an embodiment of the present invention includes an element information storage unit for storing information of a bitstream syntax element; The order of interpretation of the syntax elements included in the header region of the input bitstream is specified using a syntax rule table, and the control information and context information are generated using the syntax element table according to the order of the specified syntax elements. A syntax parser configured to interpret a subsequent bitstream syntax using the control signal and the context information stored in the storage; And a decoding processor to decode data included in the bitstream into moving image data using the control signal and the context information. Therefore, according to the present invention, it is possible to decode bitstreams encoded in various formats according to each standard by the same information recognition scheme.

MPEG, video, bitstream, decoding, syntax, semantic

Description

Decoding device and method for analyzing syntax to decode bit-stream}

1 is a diagram schematically showing a configuration of a general decoder.

2 is a diagram schematically illustrating a configuration of a general encoder.

3 is a diagram schematically showing a configuration of a decoder according to an embodiment of the present invention.

4 is a view schematically showing the configuration of a syntax analysis unit according to an embodiment of the present invention.

5 is a diagram illustrating a syntax interpretation process according to an embodiment of the present invention.

6 is a diagram schematically showing a configuration of an encoder according to an embodiment of the present invention.

The present invention relates to bitstream decoding, and more particularly, to a decoding apparatus and a syntax analysis method for bitstream decoding.

In general, a video is converted into a bitstream form by an encoder. In this case, the bitstream is stored according to an encoding type satisfying the constraint of the encoder.

MPEG requires the order of syntax (syntax, hereinafter referred to as 'syntax'), semantics (hereinafter, referred to as 'semantics') and syntax as constraints of the bitstream.

syntax indicates the structure, format, and length of the data, and in what order the data is represented. That is, syntax is to fit a grammar for encoding / decoding, and defines the order of each element included in the bitstream, the length of each element, and the data format.

Semantics means what each bit of data means. That is, semantics indicates what the meaning of each element in the bitstream is.

Therefore, various types of bitstreams may be generated according to encoding conditions of an encoder or an applied standard (or codec). In general, each standard (eg MPEG-1, MPEG-2, MPEG-4, MPEG-4 AVC, etc.) has a different bitstream syntax.

Accordingly, bitstreams encoded according to each standard or encoding condition may have different formats (ie, syntax and semantics), and a decoder corresponding to an encoder should be used to decode the bitstream.

As described above, the conventional bitstream decoder has a limitation of satisfying the constraints of the encoder, and this limitation causes a difficulty in implementing an integrated decoder corresponding to a plurality of standards.

Accordingly, the present invention is to solve the above-described problem, and is encoded in various formats (syntax, semantics) according to each standard (for example, MPEG-1, MPEG-2, MPEG-4, MPEG-4 AVC, etc.) The present invention provides a decoding apparatus capable of decoding a bitstream using the same information recognition scheme and a syntax analysis method for decoding a bitstream.

Another object of the present invention is to provide a decoding apparatus capable of easily interpreting bitstream syntax so that various types of bitstreams can be decoded in an integrated codec and / or a general codec, and a syntax analysis method for decoding a bitstream. .

It is still another object of the present invention to provide a decoding apparatus capable of commonly applying a syntax analysis method for decoding various types of bitstreams and a syntax analysis method for bitstream decoding.

It is still another object of the present invention to provide a decoding apparatus and bitstream decoding that allow components used for bitstream decoding to share element information (ie, information generated by syntax element interpretation) of parsed syntax. Is to provide a syntax interpretation method.

Still another object of the present invention is a decoding apparatus and syntax for bitstream decoding that can use element information (element information, that is, information generated by syntax element interpretation) of parsed syntax for subsequent bitstream syntax element interpretation. To provide an interpretation method.

Further, another object of the present invention is to internationally standardize the concept and structure of the integration of bitstream decoding, and other objects of the present invention will become clearer through the preferred embodiment described below.

According to an aspect of the present invention, a decoder is provided to achieve the above object.

A decoder according to an embodiment of the present invention includes an element information storage unit for storing information corresponding to a bitstream syntax element; The order of interpretation of the bitstream syntax elements included in the header region of the input bitstream is specified using syntax rule information, and the control signal and context information are generated using syntax element information according to the order of the specified syntax elements. A syntax analyzer for storing the element information storage unit; And a decoding processing unit which decodes data included in the bitstream into moving image data using the control signal and the context information.

The syntax interpreter may generate the meaning and the corresponding value of the control signal and the context information by using control signal and context information (CSCI) information and may further store the element information storage.

The syntax rule information, the syntax element information, and the CSCI information may be implemented as a binary code.

The syntax analyzing unit reads an appropriate control signal and context information among the control signal and context information stored in the element information storage unit, and analyzes a current syntax element.

Hereinafter, exemplary embodiments of a decoding apparatus and a syntax analysis method for bitstream decoding according to the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention with reference to the accompanying drawings, the same or corresponding components will be given the same reference numerals and redundant description thereof will be omitted.

Common decoders and encoders

FIG. 1 is a diagram schematically showing a configuration of a general decoder, and FIG. 2 is a diagram schematically showing a configuration of a general encoder.

As shown in FIG. 1, the MPEG-4 decoder 100 generally includes a variable length decoding unit 110, an inverse scan unit 115, and an inverse DC / AC prediction unit. / AC Prediction (120), Inverse Quantization (125), Inverse Discrete Cosine Transform (Inverse Discrete Cosine, 130), and Video Restoration (VOP Reconstruction, 135). It is apparent that the configuration of the decoder 100 may be different according to the applied standard, and some components may be replaced with other components.

When the transmitted bitstream is parsed and parsed to extract image data except for a header, the variable length decoding unit 110 generates a quantized DCT coefficient using a Huffman table, and the inverse scan unit 115 performs an inverse scan. To generate data in the same order as the video. That is, the inverse scan unit 115 outputs a value in reverse of the order of scanning in various ways during encoding. After quantization is performed during encoding, a scan direction may be defined according to a distribution of values of frequency bands. Generally, zig-zag scan method is used, but there are several scan methods for each codec.

Syntax parsing may be performed integrally in the variable length decoding unit 110 or may be performed in any component that processes the bitstream prior to the variable length decoding unit 110. In this case, since syntax parsing is the same as that of the standard applied to the encoder and the decoding period, the syntax parsing is performed only by a predetermined standard corresponding to the standard.

The inverse DC / AC predictor 120 determines the direction of the reference block for prediction by using the magnitude of the DCT coefficient in the frequency band.

The inverse quantizer 125 inverse quantizes the inversely scanned data. In other words, the DC and AC coefficients are reduced by using a quantization parameter (QP) specified during encoding.

The inverse DCT unit 130 performs inverse discrete cosine transform to obtain a real video pixel value to generate a VOP (Video Object Plane). The video restoring unit 135 restores and outputs a video signal by using the VOP generated by the inverse DCT unit.

As shown in FIG. 2, the MPEG-4 encoder 200 generally includes a DCT unit 210, a quantizer 215, a DC / AC predictor 220, a scan unit 230, and a variable length encoder ( 235).

Each component included in the encoder 200 performs the inverse function of the components included in the decoder 100 to correspond to each other, which is obvious to those skilled in the art. In brief, the encoder 200 converts a video signal (ie, a digital image pixel value) into a frequency value through discrete cosine transform, quantization, and the like, and encodes the frequency value, and then, the frequency of information. Variable length encoding is performed to differentiate the bit length according to the number, and the bit length is output in the compressed bitstream state.

Decoder and syntax interpretation method according to the present invention

3 is a diagram schematically showing the configuration of a decoder according to an embodiment of the present invention, FIG. 4 is a diagram schematically showing the structure of a syntax analysis unit according to an embodiment of the present invention, and FIG. A diagram illustrating a syntax interpretation process according to an embodiment of the present invention.

As shown in FIG. 3, the decoder 300 according to the present invention further includes a Syntax analyzer 310 compared to a conventional decoder (hereinafter, referred to as a 'decoding processor'). The configuration of the decoder 300 shown is merely an example, and the configuration is sufficient to reconstruct the input bitstream into a video, and may be configured differently according to the applied standard. The conventional decoding processor 100 may further include components for syntax parsing, but there are many differences in the syntax processing between the two, which will be easily understood through the following description.

Syntax analysis unit 310 may be provided to precede the variable length decoding unit 110 as shown in FIG. This is interpreted by the Syntax analysis unit 310 when the variable length decoding unit 110 generates the semantic data by reading the data of the specific length region as the information included in the header region of the bitstream and performing Huffman decoding. This is because / generated element information is available.

Of course, the syntax analyzer 310 may be inserted into the variable length decoding unit 110 or may be combined with the variable length decoding unit 110 in parallel. However, in order for the syntax analysis unit 310 coupled in parallel with the variable length decoding unit 110 to interpret / generate element information and store the element information in the element information storage unit 320, the bit received by the variable length decoding unit 110 is stored. The stream (or header area information) should be provided to the syntax analyzer 310.

The syntax analyzer 310 may be implemented by, for example, a finite state machine (FSM).

The syntax analyzer 310 may use the Syntax rule information extracted from the Universal Bit-stream, the prestored Syntax element table, and the Control signal / context information table. Element information corresponding to the syntax element (e.g., order of syntax elements, length of syntax elements, data type of syntax elements, syntax of each syntax element, use of each syntax element) Ranges of other components, etc.) are sequentially interpreted and stored in the element information storage 320. That is, the element information may include a SET output value, a CSCIT output value, and the like, which will be described below.

The variable length decoding unit 110 may use element information stored in the element information storage unit 320 to generate semantics data.

As another method, the syntax analyzing unit 310 may transmit the analyzed element information to the variable length decoding unit 110, and if necessary, entropy decode the corresponding element information and store it in the element information storage unit 320.

As such, the entity that stores the element information in the element information storage unit 320 may be a syntax analyzer 310 or a variable length decoding unit 110, which may be designated by design or implementation convenience. Of course, the element information storage subject may be the syntax analyzer 310 and the variable length decoding unit 110, and it is natural that the type of the element information stored in each may be different. This is the same below.

The universal bitstream in the present specification refers to a bitstream further including a syntax rule table in an arbitrary region in addition to the general bitstream generated by the conventional encoder 200. Syntax rule information is inserted or added to any area of the conventional bitstream to form an extended bitstream. More preferably, the rule information may be provided before the header information of the conventional bitstream.

It is apparent that the extended bitstream may further include at least one of a Syntax element table and a Control signal / context information table in addition to the Syntax rule table. However, when at least one of the syntax element table and the control signal / context information table is not included in the extended bitstream, they are provided in advance by the decoder 300 or the syntax analyzer 310. Should be.

In addition, the Syntax rule table, Syntax element table, Control signal / context information (Control signal / context information) table is shown and described in the form of a table for convenience, but it is obvious that each information may be listed and displayed sequentially. .

For example, the Syntax rule table, Syntax element table, Control signal / context information table may be any information displayed and / or described in binary code form. Therefore, the representation of the corresponding information can be simplified, the representation of the processing contents (Process-see Table 2) of the Syntax element table can be simplified, and the implementation and compilation can be simplified. In addition, a single syntax parsing function enables the parsing of various standard bitstream syntaxes.

The decoder 300 according to the present invention may receive the extension bitstream from the encoder and decode the video data included in the extension bitstream, but may receive only the bitstream from the encoder. In this case, the decoder 300 further adds at least one of Syntax rule information (and Syntax element table and Control signal / context information table) from the encoder in the form of separate data or electronic file. Will be received).

However, in the present specification, the encoder 1000 according to the present invention generates one extension bitstream by using the syntax rule information and the bitstream, and the decoder 300 uses the bit information by using the rule information included in the extension bitstream. The following description mainly focuses on decoding the compressed data included in the stream.

When the syntax analysis unit 310 is provided at the front of the variable length decoding unit 110 as shown in FIG. 3, the variable length decoding unit 110 uses the input bitstream to store element information stored in the element information storage unit 320. Semantics data can be generated. As described above, the variable length decoding unit 110 may entropy decode and store the element information received from the syntax analyzer 310 in the element information storage unit 320 when necessary.

4 schematically illustrates a configuration of the syntax analyzer 310.

As shown in FIG. 4, the syntax analysis unit 310 includes an analysis execution unit 410, and the analysis execution unit 410 includes a syntax element table 420 and a CS (control information) CI (context information) table. In operation 430, the syntax elements included in the header region of the bitstream are analyzed using the syntax rule table 440, and element information is extracted or generated and stored in the element information storage 320. As described above, the analysis performing unit 410 transmits the extracted or generated element information (for example, an interpreted value) to the variable length decoding unit 110, and the variable length decoding unit 110 receives the received element. Obviously, the information may be converted into semantic data and stored in the element information storage 320.

The syntax element table 420 and the CS (control information) CI (context information) table 430 may be provided in the syntax analysis unit 310. For example, when the syntax analysis unit 310 is implemented as a combination of program codes, the syntax corresponding to the syntax information table 420 and the CS (control information) CI (context information) table 430 are included. Can be.

Alternatively, the syntax element table 420 and the CS (control information) CI (context information) table 430 may be referred to during the syntax analysis by the analysis execution unit 410 in a state of being stored in a separate storage unit.

Similarly, the Syntax rule table 440 included in the extended bitstream or received as separate data may be inserted into the Syntax interpreter 310 or stored in a separate storage to be referred to for operation of the Syntax interpreter 310. have.

Element information stored in the element information storage unit 320 may be referred to by each component operating for interpreting a subsequent bitstream syntax and / or for decoding a bitstream.

Element information stored in the element information storage unit 320 may include an element name and an actual value of an element analyzed using the syntax table 420, the CSCI table 430, and the syntax table 440.

Element information that may be provided by the Syntax element table 420, the CSCI table 430, and the Syntax rule table 440 in the syntax element interpretation may include, for example, the order of syntax elements, the length of syntax elements ( length), the data type (syntax type) of the syntax elements, the interrelationship of each syntax element, and the range of other components that use each syntax element.

Hereinafter, the syntax analysis method by the analysis execution unit 410 will be described in detail. For convenience of description, the syntax element table 420 is referred to as 'SET', the CS (control information) CI (context information) table 430 is referred to as 'CSCIT', and the syntax rule table 440 is referred to as 'RT'. It will be called.

The analysis performer 410 extracts the RT 440 from the received extended bitstream or receives the RT 440 as separate data.

The RT 440 may be configured as shown in Table 1 below.

Table 1. Configuration of RT

Index No. Input No. of branches Branch 1 Branch 2 RE - R0 - One TRUE → (S1, R1) R1 C1 2 C1 == FALSE → (NULL, RE) C1 == TRUE → (S2, R2) R2 - One TRUE → (S3, R3) R3 C1 2 C1 == FALSE → (S5, R4) C1 == TRUE → (S4, R5) R4 C1 2 C1 == FALSE → (NULL, RE) C1 == TRUE → (S6, R6) R5 - One TRUE → (S5, R4) R6 C4 2 C4 == FALSE → (S9, R9) C4 == TRUE → (S7, R7) R7 - One TRUE → (S8, R8) R8 - One TRUE → (S9, R9) R9 C1 2 C1 == FALSE → (NULL, RE) C1 == TRUE → (S10, R10) … … … … …

1) RE: syntax decoding error

The analysis performing unit 410 may recognize connection information between syntax elements of the input bitstream using RT.

As shown in Table 1, the RT 440 is an 'Index No. field' for identifying a connection relationship between each Syntax element, and an input value (ie, element information) for connection control between each Syntax element. 'Input field', which is any element information (control signal and contextual information) already stored in the storage 320, and a 'No. of branches' indicating the number of elements that can be connected to the current Syntax element. Field ', a' branch # field 'indicating a branch path corresponding to each branch condition.

The 'input field' exists only when there are multiple Syntax elements that can be connected, and branching can be controlled using this value. For example, 'index number' R2 has no branch because there is no branch, but 'index number' R3 has branch, so there is an input.

In the 'branch path field', there is a branch condition (for example, C4 == FALSE) for branching to the corresponding path, and when there is no branch condition, it is always recognized as 'TRUE', such as 'index number' R5. After the branch condition, the syntax element designation information (for example, index number in SET 420, such as 'S9') and the next connection information on RT 440 (for example, RT (440), such as 'R9' Index numbers) are denoted as pairs.

As described above, the decoder 300 according to the present invention changes only the corresponding information to the RT 440 even when a new standard is generated or a syntax structure of the existing standard is changed (for example, modified, added or deleted). For example, by modifying, adding or deleting, the interpretation of the syntax element of the input bitstream may be performed.

Also, the analysis performing unit 410 extracts or generates a SET output value using the syntax element designation information with reference to the SET 420 and stores it in the element information storage unit 320. As described above, the analysis performing unit 410 transmits the extracted or generated element information (for example, an interpreted value) to the variable length decoding unit 110, and the variable length decoding unit 110 receives the received element. Obviously, the information may be converted into semantic data and stored in the element information storage 320. The SET output value may be a control signal and context information.

SET 420 may be configured as shown in Table 2 below.

Table 2. Configuration of SET

Index No. Name of Syntax Element Input Output Process S1 Vo_sequence_start_code 32 bit string C1 Read ibs if ibs == 0x000001B1, C1 = TRUE else C1 = FALSE S2 Profile_level_indication 8-bit integer C2 Read ibs C2 = ibs S3 User_data_start_code 32-bit string C1 Read ibs If ibs == 0x000001B2, C1 = TRUE Else C1 = FALSE

S4 User_data 8bit string C3 Char a1, a2; While (TRUE) {Read ibs; If (ibs == 0x00) {A1 = ibs; Read ibs; if (ibs == 0x00) {A2 = ibs; Read ibs; If (ibs == 0x00 ibs == 0x01) {Unread ibs; Unread a2; Unread a1; Break; } Else {concatenate (C3, A1); concatenate (C3, A2); concatenate (C3, ibs); }} Else {concatenate (C3, A1); concatenate (C3, ibs); }} Else concatenate (C3, ibs); } S5 Vo_start_code 32-bit string C1 Read ibs If ibs == 0x000001B5, C1 = TRUE Else C1 = FALSE S6 Is_VO_identifier 1-bit flag C4 Read ibs C4 = ibs S7 VO_verid 4-bit C5 Read ibs C5 = ibs S8 VO_priority 3-bit C6 Read ibs C6 = ibs S9 VO_type 4-bit C1 Read ibs If (ibs == '001' C1 = TRUE Else C1 = FALSE S10 Video_signal_type 1-bit C7 Read ibs C7 = ibs … … … … …

1) ibs: input bit string

2) vbs: variable bit string

3) In describing the process of SET, there may be repetitive operations (such as S6, S7, S8, S10)

As shown in Table 2, SET 420 is composed of the index, name, input data, output data and processing contents for each Syntax element.

The index is a delimiter used as the syntax element specification information in the RT 440, and the input data indicates the length of the corresponding data as data of the bitstream. The output data functions as control signals and context information, and is generated or extracted by processing contents designated by indexes of respective syntax elements. For reference, in the general case, the variable length decoding unit 110 needs to convert the semantic data into a designated process. This is the case when the variable data table exists. However, if a variable length table is not needed, the original syntax value itself is processed by a specified processing procedure. In Table 2, some symbols (e.g., C1) for identifying the output (CSCI) data corresponding to each Syntax element are shown to be partially redundant, but only to ensure that each symbol matches the index of the CSCIT 430. It is obvious that a symbol (e.g., C1) corresponding to each of the entire Syntax elements can be specified to be inconsistent, as long as it can generate the corresponding CSCIT output.

For example, the name of the Syntax element having index 'S1' is 'Vo_sequence_start_code', and the input data is a 32-bit string in the bitstream, and a SET output value corresponding to any processing content is generated or extracted.

When the analysis performing unit 410 generates or extracts the SET output value using the SET 420, an iterative operation is performed on any syntax element (for example, indexes S2, S6, S7, S8, S10, etc.). You may.

The CSCIT 430 generates detailed information (ie, CSCIT output value) of the SET output value generated or extracted by the analysis performing unit 410 using the SET 420 and stored in the element information storage unit 320. The generated CSCIT output value is stored in the element information storage unit 320. Here, the output value of the CSCIT may include the meaning of the CSCI and a corresponding actual value.

The CSCIT 430 may be configured as shown in Table 3 below.

Table 3. Composition of CSCIT

Index No. Control signal / context information Description Global / local C1 DECODE_OK Bool 1 bit flag Syntax FU C2 PROFILE_LEVEL_INDICATION 8-bit integer All C3 USER_DATA 8-bit integer * All C4 IS_VO_IDENTIFIER 1-bit flag Syntax FU C5 VO_VER_ID 4-bit flag All C6 VO_PRIORITY 3-bit All C7 VIDEO_SIGNAL_TYPE 1-BIT Syntax FU … … … …

1) *: sequence or array

2) Global / local: if a CSCI is used only in Syntax parsing Functional Unit (FU), it is local.

As shown in Table 3, the CSCIT 430 includes an index identified by an identifier of a SET output value (for example, C1), a name of the SET output value, characteristics of the SET output value, and a range in which the SET output value is used (i.e., decryption). Some processes (for example, Syntax parsing process, etc.) of the entire process or the entire decryption process for.

Hereinafter, referring to FIG. 5, the syntax analyzing unit 310 briefly describes a syntax analysis process of a header region of a bitstream. The circled figure indicated by a blank in FIG. 5 means a 'Null' value (see RT 440).

First, when the bitstream is input, the syntax analyzing unit 310 starts the operation from the index number 'R0' by the RT (440-Table 1).

Since the syntax analysis unit 310 does not need an input value to perform the index number 'R0' of the RT 440, the syntax is interpreted as satisfying the 'True' condition, and the index number 'S1' of the SET (420-Table 2) is interpreted. Proceed. That is, as shown in Table 2, the index number 'R0' of the RT (440) is set when the branch condition is 'TRUE-> (S1, R1)', and satisfies the 'True' condition, SET (420-) After performing the index number 'S1' of Table 2), it is designated to perform the index number 'R1' of the RT 440.

The syntax analyzing unit 310 reads out the syntax element 'V0_sequence_start_code' consisting of a 32-bit string in the header area of the bitstream to perform the index number 'S1' of the SET 420. Since a method for reading each syntax element in the header region of the bitstream is apparent to those skilled in the art, a description thereof will be omitted. Subsequently, the syntax analyzing unit 310 determines whether the read value is 'True' or 'False' when the read value is based on the processing content (that is, if ibs == 0x000001B1), and stores the determined information as a SET output value. Stored in the unit 320. As described above, the storage of the element information corresponding to the element information storage unit 320 may be performed by the variable length decoding unit 110.

In addition, the syntax analysis unit 310 reads the CSCIT output value (ie, meaning and corresponding value of CSCI) corresponding to the determined SET output value (ie, C1) using the CSCIT 430 to read the element information storage unit. Save to 320.

After the execution of the index number 'S1' of the SET 420 is completed, the syntax analyzer 310 proceeds to perform the index number 'R1' of the RT 440.

Since the syntax analysis unit 310 requires the input value 'C1' to perform the index number 'R1' of the RT 440, the control stored in the element information storage unit 320 by performing the previous index number 'R0'. The signal and the context information are read and used as input values.

As described above, the syntax analysis unit 310 according to the present invention may use the information extracted or generated through the previous syntax analysis of the syntax element. Similarly, it is apparent that the element information stored in the element information storage 320 (ie, information derived from the SET output value and the CSCIT output value) may be used by other components in the decoding process of the bitstream.

The syntax analyzing unit 310 performs the index number 'S2' of the SET 420 when the CSCI information read from the element information storage unit 320 is 'True' to perform the index number 'R1' of the RT 440. (And the CSCIT 430 generates the CSCIT output value according to the processing result of the index number 'S2' of the SET 420), and then proceeds to the index number 'R2' of the RT (440). However, if the read CSCI information is 'False', it proceeds to 'NULL' and processes it as a Syntax decoding error (index number 'RE').

By repeating such a process, the syntax analysis process of the header region of the bitstream shown in FIG. 5 may be completed. The element information extracted or generated in the syntax analysis process may be stored in the element information storage unit 320 and used in the subsequent process of analyzing or decoding the syntax element.

The above-described syntax analysis process is shown as a table below.

Table 4. Syntax Analysis Flow

Control flow Branch Control SET CSCIT Description One R0 2 S1 C1 Vo_sequence_start_code 3 R1 C1 4 S2 C2 Profile_level_indication 5 R2 6 S3 C1 User_data_start_code 7 R3 C1 8 S4 C3 User_data 9 R5 10 S5 Vo_start_code 11 R4 12 S6 Is_VO_identifier 13 R6 14 S9 VO_type … … … … …

The flow of Table 4 is interpreted in zigzag order from the upper left. That is, the analysis execution unit 410 will proceed to analyze the syntax elements in the order of R0, S1, C1, C1 is used as an input value of R1, and then proceeds to analyze the syntax elements in the order of S2, C2 and the like.

Encoder according to the present invention

6 is a diagram schematically illustrating a configuration of an encoder according to an embodiment of the present invention.

As shown in FIG. 6, the encoder 600 according to the present invention further includes an RT information generator 610 as compared to a conventional encoder 200 (hereinafter, referred to as an “encoding processor”). The configuration of the encoder 600 shown is merely shown as an example, and the configuration may be sufficient to encode an input video into a bitstream, and may be configured differently according to the applied standard.

As shown in FIG. 5, the RT information generating unit 610 may be coupled to be dependent on the variable length encoding unit 230, inserted into the variable length encoding unit 230, or provided at a rear end of the variable length encoding unit 230. It may be. In general, the generation of the RT 440 may be performed continuously and continuously in the encoding process. Of course, the location of the RT information generator 610 may vary depending on the design and implementation method. For example, the RT information generator 610 may be implemented as a finite state machine (FSM).

Since the form in which the RT information generating unit 610 generates the RT 440 information may be easily understood through the contents of the decoder 300 described above in detail, a description thereof will be omitted. In addition, since the components necessary for the RT information generation unit 610 to generate the RT information will also be apparent to those skilled in the art, description thereof will be omitted.

The RT information generator 610 may generate an extended bitstream into which the generated RT information is inserted or request that the variable length encoder 230 generate an extended bitstream. In addition, the RT information generated by the RT information generator 610 may be transmitted to the decoder 300 in the form of independent data or file by the RT information generator 610 or the variable length encoder 230. have. In addition, as described above, the RT information generator 610 may further provide at least one of the SET 420 and the CSCIT 430 to the decoder 300 in addition to the RT 440.

In this specification, the variable length encoder 230 refers to an arbitrary component (for example, an encoder) that performs encoding in order to generate a bitstream in the encoder 600, but is not limited thereto. In addition, this does not limit the scope of the present invention.

As described above, the decoding apparatus and the syntax interpretation method for bitstream decoding according to the present invention facilitate the interpretation of syntax elements within one standard (or codec) or between other standards (or codec). That is, it is not a problem to change the order of syntax elements, insert new syntax elements, or delete existing syntax elements in a bitstream generated according to a specific standard.

In addition, according to the related art, when the syntax element is manipulated, the decoder cannot decode the corresponding bitstream normally. For example, if the bitstream information is ABC and the bitstream is changed to ACB to configure and transmit the bitstream, the decoder cannot recognize the bitstream and thus normal decoding is not possible. The same applies to the case where a new stream is inserted into an ABFC, or a B is deleted to form a bitstream with AC.

However, using the decoding apparatus and the syntax parsing method for bitstream decoding according to the present invention, since the RT 440 is provided as data included in the extended bitstream or as independent data, the decoder can perform a smooth decoding operation.

Although the decoding apparatus and the syntax parsing method for bitstream decoding according to the present invention have been described based on MPEG-4, the MPEG-1, MPEG-2, MPEG-4 AVC and other video encoding / decoding standards are not described. Of course, the same can be applied without limitation.

As described above, the decoding apparatus and the syntax parsing method for bitstream decoding according to the present invention may be implemented in various formats (for example, MPEG-1, MPEG-2, MPEG-4, MPEG-4 AVC). syntax, semantics) can be decoded using the same information recognition method.

In addition, the present invention has the effect that it is easy to interpret the bitstream syntax to be able to decode the various forms of the bitstream in the integrated codec and / or general codecs.

In addition, the present invention has the effect that can be commonly applied to the syntax analysis method for decoding various types of bitstream.

In addition, the present invention also has the effect of allowing the components used for bitstream decoding to share element information (ie, information generated by syntax element interpretation) of the parsed syntax.

The present invention also has the effect that the element information of the parsed syntax (element information, i.e., information generated by parsing syntax element) can be used for interpretation of subsequent bitstream syntax elements.

Although the above has been described with reference to a preferred embodiment of the present invention, those skilled in the art to which the present invention pertains without departing from the spirit and scope of the invention as set forth in the claims below It will be appreciated that modifications and variations can be made.

Claims (4)

An element information storage unit for storing information corresponding to a bitstream syntax element; The order of interpretation of the bitstream syntax elements included in the header region of the input bitstream is specified using syntax rule information, and the control signal and context information are generated using syntax element information according to the order of the specified syntax elements. A syntax analyzer for storing the element information storage unit; And And a decoding processor to decode data included in the bitstream into moving image data using the control signal and the context information. The method of claim 1, And the syntax analyzing unit generates the meanings and corresponding values of the control signals and the context information by using control signal and context information (CSCI) information and further stores them in the element information storage unit. The method of claim 2, And the syntax rule information, the syntax element information, and the CSCI information are implemented in binary code. The method of claim 1, And the syntax analyzing unit reads an appropriate control signal and context information among the control signal and context information stored in the element information storage unit, and performs interpretation of a current syntax element.

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