KR100919887B1 - Apparatus and method for controlling output of intra mode decoding, and intra mode decoding system using it - Google Patents

Abstract

The present invention relates to an intra mode decoding output control apparatus and a method thereof, and to an intra mode decoding system using the same. In outputting a prediction result of an intra mode decoder to an outside, the present invention relates to an intra prediction decoding region according to a characteristic of an intra prediction mode. In the prediction mode in which data redundancy exists in the prediction result (for example, in the DC prediction mode), the transmission efficiency is improved by excluding duplicate data and outputting the prediction result.

To this end, the present invention provides an intra mode decoding output control apparatus for controlling an output (prediction result) of an intra mode decoder, comprising: input means for receiving a prediction result from the intra mode decoder; And an output control means for outputting the prediction result input through the input means to each decoding unit region to the outside, and removing and outputting data redundancy based on the characteristics of the intra prediction.

Description

Intra-mode decoding output control apparatus and method, and the intra-mode decoding system using the same [APPARATUS AND METHOD FOR CONTROLLING OUTPUT OF INTRA MODE DECODING, AND INTRA MODE DECODING SYSTEM USING IT}

The present invention relates to an intra mode decoding output control apparatus and a method thereof, and to an intra mode decoding system using the same. More particularly, in outputting a prediction result of an intra mode decoder to the outside, a decoding unit according to the characteristics of the intra prediction mode. In the prediction mode in which data redundancy exists in the intra prediction result for the region (for example, in the DC prediction mode), the intra mode excludes duplicate data and outputs the prediction result, thereby increasing transmission efficiency. A decoding output control apparatus and its method, and an intra mode decoding system using the same.

The present invention is derived from a study conducted as part of the IT new growth engine core technology development project of the Ministry of Information and Communication and the Ministry of Information and Communication Research and Development. [Task Management Number: 2005-S-078-02, Title: Low-Power Graphic Processing SoC Platform] .

A video decoder that conforms to the H.264 Recommendations decodes the picture into two modes. That is, the I picture decodes all the macroblocks in the picture in the intra mode, that is, decodes using the result value of the adjacent macroblock in the same picture which has already been decoded, and the macroblock (inter mode macroblock) of the P picture is already A motion compensation method using the decoded past screen (that is, interpolated and decoded a predetermined area of the past screen) is decoded.

The basic intra mode decoding method obtains a prediction picture using adjacent pixels in a decoding unit region (for example, 16x16 pixels in I 16x16 mode, 4x4 pixels in I 4x4 mode, and 8x8 pixels in chromaticity signal). . Looking at the result predicted by this method, the prediction result of the luminance signal Y is 16x16 pixels, the prediction result of the chroma signal U is 8x8 pixels, and the prediction result of the chroma signal V is 8x8 pixels.

In view of the characteristics of the intra mode decoding result, (1) In the case of the I 16x16 mode, if the prediction mode is the DC mode (Intra_16x16_DC), the result value of 16x16 pixels is the same as the average value of the adjacent pixels. In addition, in the case of (2) I 4x4 mode, if the prediction mode of the corresponding block is the DC mode (Intra_4x4_DC), the result value of 4x4 pixels is the same as the average value of adjacent pixels. (3) As for the chromatic component, if the prediction mode is DC mode (Intra_Chroma_DC), the result values of all 4x4 pixels in 8x8 pixels are all the same.

Therefore, the conventional method of transmitting all of the prediction results (Y, U, V: 16x16, 8x8, 8x8) for each decoding unit region without considering the characteristics of the intra prediction modes described above is redundant. There is a problem in that the transmission efficiency is lowered due to the data transmission.

That is, the conventional method has the problem that the transmission efficiency is lowered due to the transmission of duplicate data by transmitting the same prediction result regardless of the characteristics of the result value according to the intra prediction mode.

The prior art as described above has a problem in that the transmission efficiency is reduced due to the output of duplicated data in outputting (transmitting) the prediction result of the intra mode decoder to the outside.

Therefore, the present invention outputs the prediction result of the intra mode decoder to the outside, in the case of the prediction mode in which data redundancy exists in the intra prediction result for the decoding unit region according to the characteristics of the intra prediction mode (for example, the DC prediction mode). In the case of the present invention, an object of the present invention is to provide an intra mode decoding output control apparatus and a method thereof, and an intra mode decoding system using the same, by which redundant data can be output by outputting prediction results.

The objects of the present invention are not limited to the above-mentioned objects, and other objects and advantages of the present invention which are not mentioned above can be understood by the following description, and will be more clearly understood by the embodiments of the present invention. Also, it will be readily appreciated that the objects and advantages of the present invention may be realized by the means and combinations thereof indicated in the claims.

In order to achieve the above object, the present invention is characterized in that in outputting (transmitting) the prediction result of the intra mode decoder, the redundant data is excluded from the output object in consideration of the characteristics of the mode used for intra prediction. .

That is, according to the present invention, in the prediction mode in which data redundancy exists in the intra prediction result for the decoding unit region according to the characteristics of the intra prediction mode, for example, in the DC prediction mode, all the prediction results are not output. It is characterized by outputting the data without redundancy.

More specifically, the present invention provides an intra mode decoding output control apparatus for controlling an output (prediction result) of an intra mode decoder, comprising: input means for receiving a prediction result from the intra mode decoder; And an output control means for outputting the prediction result input through the input means to each decoding unit region to the outside, and removing and outputting data redundancy based on the characteristics of the intra prediction.

On the other hand, the present invention, in the intra mode decoding output control method for controlling the output (prediction result) of the intra mode decoder, the prediction result using the macroblock type and prediction mode input from the intra mode decoder for each decoding unit region A determination step of determining whether data redundancy exists; A first output control step of outputting the prediction result to the outside by removing data redundancy with respect to a decoding unit region having data redundancy as a result of the determination; And a second output control step of outputting all of the prediction results to the outside for the decoding unit region having no data redundancy.

On the other hand, the present invention provides an intra mode decoding system comprising: intra mode decoding means for outputting a prediction result by performing intra mode decoding on a block basis; And an intra-mode decoding output control means for controlling an external output of the prediction result, but excluding duplicate data according to the intra prediction mode from the output target.

As described above, unlike the conventional method of transmitting all prediction results (Y, U, V: 16x16, 8x8, 8x8 pixels) in any mode regardless of the mode used for intra prediction, By excluding and transmitting duplicate data for a specific mode, there is an effect of increasing the transmission efficiency.

1 is a configuration diagram of an intra mode decoding output control apparatus and an intra mode decoding system using the same according to an embodiment of the present invention;

2 is a flowchart of an embodiment of an intra mode decoding output control method according to the present invention;

3 is an explanatory diagram illustrating a prediction method of 16x16 intra prediction mode in H.264 decoding;

4 is an explanatory diagram for explaining a 4x4 intra prediction mode prediction method in H.264 decoding;

5 is an explanatory diagram for an intra prediction method of chroma components in H.264 decoding.

* Explanation of symbols on the main parts of the drawings

10: intra mode decoding system 100: intra mode decoder

110: intra mode decoding output control device 111: input unit

112: output control unit

First, the specific content of the present invention as a whole, as follows.

In the intra prediction mode of the H.264 intra mode, in the case of a specific mode (for example, the DC mode), the prediction result value is a constant region (a 16x16 or 4x4 decoding unit region for a luminance signal, and an 8x8 decoding unit region for a chroma signal. For all 4x4 pixelblocks). Therefore, the present invention utilizes such a characteristic to control the output of one prediction result (the prediction result of one pixel) instead of transmitting all the data (the prediction result) of a certain region for a specific mode (DC mode). It is characterized by controlling the number of outputs of the decoder variably.

The above objects, features and advantages will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, whereby those skilled in the art may easily implement the technical idea of the present invention. There will be. In addition, in describing the present invention, when it is determined that the detailed description of the known technology related to the present invention may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted. Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a configuration diagram of an intra mode decoding output control apparatus and an intra mode decoding system using the same according to an embodiment of the present invention.

The intra mode decoding system 10 according to the present invention includes an intra mode decoder 100 and an intra mode decoding output control apparatus 110 as shown in FIG. 1.

In this case, the intra mode decoder 100 performs intra decoding on luminance (Y) and chroma (U, V) of image data on a block basis by using various conventional intra prediction techniques, and outputs a prediction result. In outputting the output (prediction result) of the intra mode decoder 100 to the outside, the mode decoding output control apparatus 110 performs a function of excluding duplicate data output using a macroblock type and a prediction mode.

Hereinafter, the intra mode decoding output control apparatus 110 will be described in detail.

As illustrated in FIG. 1, the intra mode decoding output control apparatus 110 controls the output (prediction result) of the intra mode decoder 100. In detail, the input unit 111 and the output control unit 112 are used. ).

That is, the intra mode decoding output control apparatus 110 outputs an output of a module (intra mode decoder) that performs intra mode decoding (intra picture prediction coding method) in a video decoding system, particularly a decoding system conforming to the H.264 recommendation. To control.

The block region (decoding unit region) that is a decoding processing unit (in the YUV 4: 2: 0 format, luminance Y corresponds to [16x16 pixels], chromaticity U corresponds to [8x8 pixels], and chromaticity V corresponds to [8x8 pixels]) is intra. In the decoding of the decoding unit region, the pattern of the prediction result value is different depending on the mode. Depending on the type of the intra mode, the prediction result values may all be the same for a certain area.

The intra mode decoding output control apparatus 110 outputs the prediction result without overlapping by using the properties (characteristics) of the intra mode prediction result as described above. That is, the intra mode decoded output control apparatus 110 has a certain area (a mode in which the prediction result is the same for all areas, i.e., a DC mode) for a certain area (16x16 or 4x4 decoding unit area for chroma signal, chromaticity). For a signal, only one value is output without transmitting all prediction result values of 4x4 pixel blocks in an 8x8 decoding unit region. By doing so, the prediction result of the intra mode decoder 100 is efficiently transmitted to the module (image reconstruction block) using the prediction result of the intra mode decoder 100.

Hereinafter, each component of the intra mode decoding output control apparatus 110 will be described in detail.

First, the input unit 111 receives a macroblock type MB_TYPE, a prediction mode, and a prediction result from the intra mode decoder 100. The input information will be described below.

The "macroblock type (MB_TYPE)" indicates the encoding mode of the macroblock. In the intra mode decoder 100, the macroblocks of "16x16 intra prediction mode (I 16x16_mode)" and "4x4 intra prediction mode (I 4x4_mode)" Target only.

The intra mode decoder 100 processes and outputs a Y 16x16 result when the macroblock type MB_TYPE is "16x16 intra prediction mode (I 16x16_mode)" in relation to the processing of the luminance signal Y, and outputs the macroblock type ( If MB_TYPE) is "4x4 intra prediction mode (I 4x4_mode)", Y 4x4 results are output in order for all 4x4 blocks (16 pieces) in the macroblock. On the other hand, in relation to chroma signal processing, U or V 4x4 results are output in order for all 4x4 blocks (4 U and 4 V) in the macroblock.

Next, the "prediction mode" of the information input to the input unit 111 will be described.

The intra mode decoder 100 which is processing the luminance signal is in the case of the "16x16 intra prediction mode" in the case of I 16x16_mode (refer to the four prediction modes in FIG. 3) or "4x4 intra prediction mode" in the "16x16 intra prediction mode" mode. Output I4x4_mode (see 9 modes in FIG. 4). In addition, when the intra mode decoder 100 performs intra prediction on the chroma signal, I_chroma_mode (see four modes of FIG. 5) is output. It is assumed that the signal output from the intra mode decoder 100 is transmitted to an image reconstruction block (not shown).

2 is a flowchart illustrating an intra mode decoding output control method according to an exemplary embodiment of the present invention, and illustrates an output control method performed by the output control unit 112 of the intra mode decoding output control apparatus 110.

First, for each decoding unit region (block region which is a decoding processing unit) (16x16 pixels, 4x4 pixels, etc.), it is checked whether the macroblock type MB_TYPE is a 16x16 intra prediction mode (I 16x16 mode) while the input is a luminance signal ( 200).

As a result of the confirmation of "200", if the luminance is 16x16 intra mode (prediction mode), the 16x16 DC prediction mode (Intra_16x16_DC) is checked again. And outputs all the predicted 16x16 prediction results (202), and outputs only the prediction value for any one pixel of the 16x16 input when the 16x16 DC prediction mode (exactly, the luminance 16x16 intra DC prediction mode) is output (203). .

As a result of the check of "200", if the luminance is not the 16x16 mode, it is checked whether the input is the luminance signal and the macroblock type (MB_TYPE) is the 4x4 intra prediction mode (I 4x4 mode) (210). In the same manner as in the DC prediction mode is checked (211). As a result of the check 210, if it is not the 4x4 DC prediction mode (Intra_4x4_DC), all 4x4 inputs (4x4 prediction results input through the input unit 111 for the corresponding decoding unit region) are output (212), and the 4x4 DC prediction mode (Intra_4x4_DC) is output. (Exactly, it may be referred to as a 'luminance 4x4 intra DC prediction mode'), only a prediction value for one pixel of the 4x4 input is output (213).

If the results of the checks "200" and "210" do not correspond to both cases, the input signal is for a chroma signal, so whether the prediction mode for the chroma signal is the DC prediction mode (I_chroma_mode == Intra_chroma_DC) is checked ( 220). As a result of confirmation of "220", if the prediction mode for the chromaticity signal is not the DC mode (Intra_chroma_DC), the 4x4 input (4x4 prediction result input through the input unit 111 for the corresponding decoding unit region) is output in full (221). In the DC prediction mode Intra_chroma_DC (exactly referred to as the chroma intra DC prediction mode), only a prediction value for any one pixel of the 4 × 4 input is output (222). This is because, in the DC prediction mode, the output of the chroma signal is controlled in units of 4x4 pixels because the prediction result is the same for every 4x4 pixels.

In other words, after checking whether the luminance 16x16 intra prediction 200, the luminance 4x4 intra prediction 210, the chroma intra prediction 210, and then again whether the prediction mode is the DC prediction mode (201, 211, 220) In the DC prediction mode, only the prediction result for one pixel is output without outputting all of the inputs. This is because the prediction result is the same in all regions of the decoding unit region because the average value is taken as a prediction value in the DC prediction mode. However, the chromaticity signal has a characteristic that the prediction result is the same for every 4x4 pixel in the decoding unit region.

FIG. 3 is an explanatory diagram illustrating a prediction method of a 16x16 intra prediction mode in H.264 decoding, and shows names and prediction methods of corresponding prediction modes for each prediction mode.

The 16x16 intra prediction mode (I 16x16_mode) has four modes as shown in FIG. 3, wherein 'mode 0' is the vertical prediction mode (Intra_16x16_Vertical prediction mode) and 'mode 1' is the horizontal prediction mode (Intra_16x16_Horizontal prediction mode). ), 'Mode 2' represents a DC mode (Intra_16x16_DC prediction mode), and 'mode 3' represents a plane prediction mode (Intra_16x16_Plane prediction mode).

FIG. 4 is an explanatory diagram illustrating a prediction method of a 4x4 intra prediction mode in H.264 decoding, and shows names and prediction methods of the prediction mode for each prediction mode.

In the 4x4 intra prediction mode I 16x16_mode for luminance Y, there are nine modes as shown in FIG. 4, wherein 'mode 0' is the vertical prediction mode (Intra_4x4_Vertical prediction mode) and 'mode 1' is the horizontal mode. Intra_4x4_Horizontal prediction mode, 'Mode 2' is the Intra_4x4_DC prediction mode, 'Mode 3' is the Intra_4x4_Diagonal_Down_ Left prediction mode, and 'Mode 4' is the Infra_4x4_Diagonal mode _Down_Right prediction mode, 'Mode 5' is Intra_4x4_Vertical _Right prediction mode, 'Mode 6' is Intra_4x4_Horizontal_Down prediction mode, 'Mode 7' is Intra_4x4_Vertical_Left prediction mode , 'Mode 8' represents an Intra_4x4_Horizontal_Up prediction mode.

FIG. 5 is an explanatory diagram of an intra prediction method of chroma components in H.264 decoding, and shows a name to a prediction method of a prediction mode for each prediction mode.

As shown in FIG. 5, the intra chroma prediction mode (I_chroma_mode) includes four modes, in which 'mode 0' is an DC mode (Intra_Chroma_DC prediction mode), 'mode 1' is a horizontal mode (Intra_Chroma_Horizontal prediction mode), 'Mode 2' represents a vertical mode (Intra_Chroma_Vertical prediction mode), and 'mode 3' represents a plain mode (Intra_Chroma_Plane prediction mode).

In summary, since the "DC prediction mode" is predicted by the average of the reference samples among the various prediction modes shown in FIGS. 3 to 5, the prediction result values are the same for all regions of 4x4 pixels or 16x16 pixels. By using this characteristic, the present invention outputs only the predicted value of one pixel for the region predicted in the DC mode.

Meanwhile, in the case of an encoder such as an H.264 encoder, an intra mode decoding process also exists, and the present invention is applied to the corresponding intra mode decoding module in this case.

On the other hand, the method of the present invention as described above can be written in a computer program. And the code and code segments constituting the program can be easily inferred by a computer programmer in the art. In addition, the written program is stored in a computer-readable recording medium (information storage medium), and read and executed by a computer to implement the method of the present invention. The recording medium may include any type of computer readable recording medium.

The present invention described above is capable of various substitutions, modifications, and changes without departing from the technical spirit of the present invention for those skilled in the art to which the present invention pertains. It is not limited by the drawings.

Claims (14)

delete delete In the intra mode decoding output control apparatus which controls the output (prediction result) of an intra mode decoder, Input means for receiving a prediction result from the intra mode decoder; And For each decoding unit region, the corresponding prediction result inputted through the input means is output to the outside, and the macroblock type and the prediction mode are checked to determine the pixel unit of the decoding unit region predicted in the luminance intra DC prediction mode. And an output control means for outputting a prediction result and outputting all prediction results of the decoding unit region for a luminance intra prediction mode other than the luminance intra DC prediction mode. The method of claim 3, wherein The luminance intra DC prediction mode, Intra mode decoding output control apparatus characterized in that the luminance 16x16 intra DC prediction mode (Intra_16x16_DC) or the luminance 4x4 intra DC prediction mode (Intra_4x4_DC). In the intra mode decoding output control apparatus which controls the output (prediction result) of an intra mode decoder, Input means for receiving a prediction result, a macroblock type, and a prediction mode from the intra mode decoder; And For each decoding unit region, the corresponding prediction result input through the input means is output to the outside, and the input macroblock type and the prediction mode are checked, and every 4x4 pixel for the decoding unit region predicted in the chroma intra DC prediction mode. And an output control means for outputting a prediction result of one pixel and outputting all prediction results of the corresponding decoding unit region for the chroma intra prediction mode other than the chroma intra DC prediction mode. delete delete delete In the intra mode decoding output control method for controlling the output (prediction result) of the intra mode decoder, A determination step of determining a decoding unit region in which the prediction mode is a DC prediction mode as a decoding unit region having data redundancy, using a macroblock type and a prediction mode input from the intra mode decoder for each decoding unit region; If the DC prediction mode is the chroma intra DC prediction mode (Intra_chroma_DC), a first output control step of externally outputting a prediction result of one pixel every 4x4 pixels of the corresponding decoding unit region; And A second output control step of outputting all the prediction results to the outside for the decoding unit region having no data redundancy as a result of the determination; Intra mode decoding output control method comprising a. delete delete delete In the intra mode decoding system, Outputs a prediction result from the intra mode decoding means, an input means for receiving a macroblock type and a prediction mode, and a corresponding prediction result input through the input means for each decoding unit region, wherein the input macroblock type and The prediction mode is checked, and a prediction result of one pixel is output for the decoding unit region predicted in the luminance intra DC prediction mode, and the prediction result of the corresponding decoding unit region for the luminance intra prediction mode other than the luminance intra DC prediction mode. Intra-mode decoding means including output control means for outputting all of them; And Intro mode decoding output control means for controlling the external output of the prediction result, but to exclude the duplicated data in the output target according to the intra prediction mode Intra mode decoding system, including. In the intra mode decoding system, Outputs a prediction result from the intra mode decoding means, an input means for receiving a macroblock type and a prediction mode, and a corresponding prediction result input through the input means for each decoding unit region, wherein the input macroblock type and The prediction mode is checked, and a prediction result of one pixel is output every 4x4 pixels for the decoding unit region predicted in the chroma intra DC prediction mode, and the decoding unit region for the chroma intra prediction mode other than the chroma intra DC prediction mode. Intra-mode decoding means including output control means for outputting all prediction results of? And Intra-mode decoding output control means for controlling the external output of the prediction result, but to exclude the duplicated data in the output target according to the intra prediction mode Intra mode decoding system comprising a.