KR100220581B1 - The vertex coding apparatus for object contour encoder - Google Patents

Abstract

In inter and intra frame mode encoding, the present invention relates to each point in a motion compensated contour that takes into account the temporal correlation between the current contour of the current frame and the previous contour of the previous frame and the angle in each corresponding line segment to be encoded currently. The present invention relates to a vertex encoding apparatus for object contour encoding that can effectively encode each vertex information of a residual contour remaining after motion compensation using distance difference information between vertices. To this end, the present invention uses a polygon approximation algorithm. Generates vertex information of each line segment for the current contour of the current frame, extracts a motion vector for the object through motion compensation using the current contour and the previous contour, and corresponds to the line segments having the respective vertex information. Movement compensation performed Calculate the relative distance information between the index information allocated to each point of the MC contour and the vertices corresponding to each point, and apply the inter mode encoding or the intra mode encoding using the calculated distance information. Selects and encodes one motion vector of the object, index information, and relative distance information between each vertex and each point on the MC contour in inter-mode encoding, and one motion vector of the object in intra-mode encoding. And encoding the relative distance information between the vertex encoded immediately before the current frame and the vertex to be encoded currently, so that the amount of transmission data (bit amount) generated when encoding the residual contour information of the object remaining after motion compensation appearing in the video signal. Can be significantly reduced.

Description

Vertex Coding Device for Object Contour Coding

1 is a block diagram of a vertex encoding apparatus for object contour encoding according to a preferred embodiment of the present invention.

2 is a diagram illustrating residual contours and motion compensated contours for vertex point encoding according to the present invention.

3 is a diagram illustrating an example of encoding relative position information between a vertex immediately encoded in a current frame and a vertex to be currently encoded in intra mode encoding according to the present invention.

* Explanation of symbols for main parts of the drawings

102: polygon approximation block 104: frame memory

106: motion compensation block 108: indexing block

110: optimal point selection block 112: relative distance calculation block

114: control block 116: switching circuit

118: location information coding block 120: buffer memory

122: vertex coding block 124: contour coding block

The present invention relates to an apparatus for encoding contour information in an object-based encoding system for compressing and encoding a video signal at a low data rate. More particularly, the present invention relates to vertex information existing on contours of inter and intra frames included in a digital video signal. The present invention relates to a vertex encoding apparatus for object contour encoding suitable for encoding a.

As is well known in the art, the transmission of discrete video signals can maintain better image quality than analog signals. When a video signal composed of a series of image "frames" is represented in digital form, a considerable amount of transmission data is generated, especially for high-definition television (HDTV). However, since the usable frequency range of the conventional transmission channel is limited, in order to transmit a large amount of digital data, it is necessary to compress the data to be transmitted and reduce its transmission amount.

Therefore, when transmitting a video signal, the transmitting system compresses and compresses the video signal by using the spatial and temporal correlation of the video signal to reduce the amount of data. To the decryption system.

Meanwhile, as various compression techniques mainly used for encoding an image signal, a hybrid encoding technique combining a stochastic encoding technique and a temporal and spatial compression technique is known to be effective.

Most of the hybrid coding schemes, which are one of the above coding techniques, use motion compensated DPCM (differential pulse code modulation), two-dimensional discrete cosine transform (DCT), quantization of DCT coefficients, VLC (variable modulation coding), and the like. Here, the motion compensation DPCM determines a motion of the object between the current frame and the previous frame, and predicts the current frame according to the motion of the object to generate a differential signal representing the difference between the current frame and the predicted value. This method is described, for example, in Staffan Ericsson's "Fixed and Adaptive Predictors for Hybrid Predictive / Transform Coding", IEEE Transactions on Communication, COM-33, NO.12 (Dec. 1985), or Ninomiy and Ohtsuka's "A motion Compensated Interframe Coding Scheme for Television Pictures ", IEEE Transaction on Communication, COM-30, NO.1 (January, 1982).

More specifically, the motion compensation DPCM predicts the current frame from the previous frame according to the motion of the object estimated between the current frame and the previous frame. Here, the estimated motion is a two-dimensional representation of the displacement between the previous frame and the current frame. It can be represented as a motion vector. Here, the pixel displacement of the object, as is well known, is input by comparing the block of the current frame with the blocks of the previous frame in units of blocks of a predetermined size (for example, 8 × 8 size) to determine an optimal matching block. Block-based motion estimation technique for estimating the inter-frame displacement vector (how much the block moved between frames) for the entire current frame, and the pixel value of the current frame in each pixel unit is estimated from the pixel values of the previous plane. It may be estimated through a compensating motion estimation technique.

Therefore, when transmitting a video signal, the transmitting side compresses and encodes the image signal in the buffer of the output side in order by taking into account the spatial and temporal correlation of the image signal in block units or pixel units through the above-described encoding technique. The image data will be transmitted to the decoding system at the receiving side via the transmission channel at a desired bit rate in response to the channel requirements.

More specifically, the coding system on the transmitting side removes spatial redundancy of the video signal using change coding such as discrete cosine transform (DCT), and further uses temporal coding of the video signal using differential coding through motion estimation and prediction. By eliminating redundant redundancy, the video signal can be efficiently compressed.

In general, the DPCM / DCT hybrid coding scheme as described above has a target bitrate of Mbps, and may be a CD-ROM, a computer, a home appliance (such as a digital VCR), a broadcast (HDTV), etc. It is mainly concerned with MPEG-1, 2 and H.261 coding algorithms related to high bit rate encoding, which mainly consider only the statistical characteristics of the block-by-block motion in the image, which has already been completed by the World Standards Organization.

On the other hand, in recent years, various devices such as home appliances can process and provide image information with vast data due to the recent improvement in PC performance and spread, the development of digital transmission technology, the realization of high-definition display devices, and the development of memory devices. In order to meet this demand, the transmission of audio-video data through existing low-speed transmission paths (eg, PSTN, LAN, mobile network, etc.) with a bit rate of Kbpa level and the limited capacity to meet these demands. There is a need for new coding techniques with high compression rates for storage to storage.

However, the existing video coding techniques described above are based on local block motion in the entire image regardless of the shape of the moving object and the global motion. Therefore, in the conventional video coding techniques, when the block-by-block motion compensation coding is applied, image quality degradation such as blocking, corner blurring, and spotting appears in the reproduced video that is finally reconstructed. In addition, the high compression rate of the image data is required in order to maintain the resolution for low-speed image transmission, but there is a problem in that it is impossible to implement the hybrid coding scheme based on the conventional DCT conversion.

Therefore, at present, there is a need for a standard of a coding scheme for additional compression realization with respect to a coding scheme based on a conventional DCT transformation. In accordance with the needs of the times, MPEG4, which focuses on subjective picture quality based on recent human visual characteristics, is required. The research on low bit rate video encoding technique for the standardization of the standard has been actively conducted everywhere.

In order to meet these needs, potential viable low-rate video coding techniques currently being studied are, for example, wave-based coding and model-based coding to improve existing coding techniques. Object-Based Coding, a kind of coding, Segmentation-Based Coding that splits and encodes an image into a plurality of subblocks, and Fractal Coding that uses image self-similarity Etc. Here, the present invention may be regarded as related to a video object-based encoding technique.

Moving object-based coding techniques related to the present invention include object-oriented analysis-synthesis coding techniques, which are described by Michael Hotter, "Object-Oriented Analysis-Synthesis Coding Based on Moving Two." -Dimensional Objects ", Signal Processing: Image Communication 2, pp. 409-428 (December, 1990).

On the other hand, according to the object-oriented analysis and synthesis coding technique described above, the input video signal is divided into arbitrary objects, and since the motion, contour, and pixel data of each object are completely different information on their data characteristics, the encoding method These are processed independently of each other, ie, through different coding channels. Therefore, information encoded through separate coding channels may be multiplexed through a multiplexer or the like and sent to a transmitter. Here, the present invention is substantially related to an apparatus for encoding the contour of an object.

In particular, in processing the contour of an object, the contour information is very important for analyzing and synthesizing the shape of the object. As a conventional coding technique for representing such contour information, for example, a chain coding method There is this. In this case, the chain encoding method is a technique of encoding contour information starting from an arbitrary point on the contour line and arranging the boundary lines as a permutation of direction vectors in a predetermined direction according to the connection state between the pixels. It is well known in the art. However, chain coding requires a substantial amount of bit allocation even if there is no loss of contour information.

In addition, several methods have been proposed for approximating contours such as polygonal approximation and B-spline approximation. Here, the main disadvantage of the polygon approximation is that the contour is rough, and the B-spline approximation can represent the contour more accurately, but the overall order of the image coding system is because it requires higher order polynomials to reduce the approximation error. Complicate the calculation.

One of the proposed methods to solve the problem of the roughness of the object in the polygon approximation as described above and the complexity of the calculation in the B-spline is the contour approximation technique using the discrete sine transform (DST). to be.

A device employing such a polygonal approximation of contours and a contour approximation technique using DST is disclosed in pending US patent application 08 / 423,604, filed under the name "contour approximation device for contouring objects". In such an apparatus, a number of vertex points are determined and the contour of the object is approximated by contour approximation that fits the contour into line segments. Then, N sample points are selected for each line segment, and an approximation error is calculated at each N sample points located on each line segment to obtain a set of approximation errors for each line segment. In this case, N sample points are arranged at equal intervals on each line segment, where each approximation error represents a distance between each of the N sample points and the contour. Then, a set of DST coefficients is generated by performing one-dimensional DST on each set of approximate errors.

Although the above-described apparatus can solve the problem of rough outlines and the complexity of calculation by using contour approximation using DST, there is a problem in that the amount of data to be transmitted increases because DST coefficients must be transmitted every frame. Therefore, in order to implement a low data rate, it is necessary to suppress an increase in data generated when performing contour approximation using DST as described above, and as a way of suppressing occurrence data of encoded contour information of an object as described above, The application of a motion estimation technique using a difference signal (error signal) generated by subtraction between the object contour data of a frame and the object contour data of a previous frame is actively referred to or considered, in which the present invention affects the reproduction quality. It is related to the coding method of vertex points on the contour, which can obtain more efficient compression rate without satisfactory.

Accordingly, in the present invention, in the inter and intra frame mode encoding, each point on a motion-compensated contour in consideration of the temporal constellation of the current contour of the current frame and the previous contour of the previous frame and each corresponding line segment to be encoded currently It is an object of the present invention to provide a vertex encoding apparatus for object contour encoding that can effectively encode respective vertex information of a residual contour remaining after motion compensation using distance difference information between respective vertices.

In order to achieve the above object, the present invention provides a device for encoding contours of an object appearing in a digital video signal having a plurality of frames including a current frame and a previous frame using motion compensation, wherein the contours are line segmented. A polygonal approximation block for performing contour approximation of an object using a contour approximation technique to generate vertex information for each line segment in the current contour of the current frame; Based on previous contour information of the previous frame, one motion vector for an object is extracted through matching between the current contour and a plurality of candidate contours in the search range in the predetermined motion search range, and the extracted one. A motion compensation block for generating at least one contour segment, at least one remaining contour, and at least one MC contour without motion compensation, which are motion compensated by motion compensation between the current contour and the previous contour using the motion vector of the motion vector; An indexing block for assigning a series of index information having an integer value for each pixel point of the generated at least one MC contour; Each point of the searched point is generated by generating starting point index information and ending point index information on each MC contour, and searching each point on the MC contour that is closest to each vertex information on each line segment corresponding to each remaining contour. An optimal point selection block for successively generating respective index information corresponding to each vertex information to be encoded assigned to the fields; A relative distance calculation block for calculating a distance value between each vertex to be encoded and each selected point on the MC contour corresponding thereto; A control block which compares each of the calculated distance values and a predetermined threshold value, and adaptively selects inter mode encoding or intra mode encoding for each vertex on the residual contour according to the comparison result; A position information generation block for encoding relative position information between the vertex information on the remaining contour from each point on the MC contour based on the calculated distance values; A switching circuit for switching on / off the output of each index information provided from the optimum point selection block based on a switching control signal from the control block; A buffer memory provided from the polygon approximation block and storing vertex information encoded immediately before vertex information to be currently encoded on the remaining contour in the current frame; A vertex encoding block that encodes relative position information between the previous vertex and the vertex to be currently encoded provided through the control block according to control from the control block during the intra mode encoding; And encoding one motion vector of the object, each index information corresponding to each vertex information, and relative position information between the vertex information from each point in the inter mode encoding, and the intra mode. The present invention provides a vertex encoding apparatus for object contour encoding including a motion vector for the object and contour encoding means for encoding relative position information between the previous vertex and the current vertex.

The above and other objects and various advantages of the present invention will become more apparent from the preferred embodiments of the present invention described below with reference to the accompanying drawings by those skilled in the art.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

First, in the vertex encoding apparatus according to the present invention, the technical gist of the present invention is to use the inter-mode encoding or the distance difference between the vertex on the residual contour to be encoded and the closest point on the MC contour obtained through motion estimation compensation. Adaptively performing intra-mode coding, i.e., the distance from the nearest point on the MC contour obtained through motion estimation compensation to the vertex (vertex for the remaining contour obtained using the polygon approximation algorithm) to be encoded currently is greater than or equal to the preset threshold. In this case, the intra mode encoding is performed, and on the contrary, the inter mode encoding is performed if it is less than the predetermined threshold.

1 shows a block diagram of a vertex encoding apparatus for object contour encoding according to a preferred embodiment of the present invention suitable for realizing the above technical gist. As shown in the figure, the improved vertex encoding apparatus of the present invention includes a polygon approximation block 102, a frame memory 104, a motion compensation block 106, an indexing block 108, and an optimal point selection block 110. ), The relative distance calculation block 112, the control block 114, the switching circuit 116, the position information coding block 118, the buffer memory 120, the vertex coding block 122, and the contour coding block 124. Include.

In FIG. 1, the polygon approximation block 102 uses a conventional approximation algorithm that outlines a line segment by inputting the boundary or contour data of an object in the current frame provided from the line L10 as input and uses the current frame on the line L11. Generates a plurality of vertex information indicating the position of the vertex points with respect to the contour of. Here, the current contour data includes boundary information, which includes position data of each pixel located along the boundary of the object in the frame. Then, a plurality of vertex information represented on the outline of the object in the current frame on the detected line L11 are provided to the optimal point selection block 110 and the buffer memory 120, which will be described later.

In this case, the vertex information encoded immediately before the vertex currently being encoded in the same frame is stored in the buffer memory 120. As described above, the previously encoded vertex information stored in the buffer memory 120 may be stored in the present invention. It is used as information for intra-mode encoding in adaptive vertex coding, and a detailed processing thereof will be described later in detail.

Next, the motion compensation block 106 extracts one motion vector through motion estimation based on the current contour data on the line L10 and the previous contour data provided from the frame memory 104 via the line L12, and thus extracted. By performing motion compensation based on the motion vector, motion compensated contour (hereinafter referred to as MC contour) information is generated. Here, the frame memory 104 delays the contour data of the object by one frame and outputs it on the line L12. Thus, the contour data of the previous object on the L12 provided by the frame memory 104 is restored from the previous frame. Previous contour information of the object.

That is, the motion compensation block 106 extracts one motion vector using the contour data of the current object on the line L10 and the contour data of the previous object on the line L12, where only one motion vector is extracted for the object. The reason for this is that the correlation of the contour image on the time axis is very small compared to the general image. Therefore, in the present invention, only one motion vector is searched for one object without allocating a large amount of information for motion compensation. To perform motion compensation. As such, an apparatus for performing motion compensation by extracting only one motion vector for one object is filed on March 22, 1996 by the applicant of the present invention under the name "contour coding system of the object and its motion estimation method". And pending Korean Patent Application No. 96-7857.

In this motion estimation method, first the object contour of the current frame is A motion search range of a predetermined range which is extended by one pixel and is preset based on the contour information of the previous frame (for example, 16-pixel range) to determine the predicted contour information by matching the determined current contour with a plurality of candidate contours, i.e., matching the current contour and the candidate contours extended in the preset search range of the previous contour, respectively. After counting the number of contour pixels, the candidate contour having the smallest count value among the candidate contours within the search range is determined as the prediction contour, and one motion vector for the prediction contour determined as described above is determined from the extended current contour. . Here, the determined motion vector is determined by the overall contour of the object in the current frame and the preset contour search range (eg, the previous contour of the previous frame). The displacement between the contour of the determined object within the 16 pixel range). This motion vector is then provided to the contour coding block 124 on the output side via line L13 for transmission to the transmitter.

In addition, the motion compensation block 106 generates motion compensated contour information by performing motion compensation using one motion vector for one object extracted through the above-described process. Is contour information of a state in which motion compensation is performed by simply moving the object contour of the restored previous frame by the extracted motion vector. Since the contour information can be shared by the encoding system or the decoding system by transmitting only the motion vector, the present invention indexes each pixel value of the motion-compensated contour information to use such information.

That is, in FIG. 2, the MC contour information (shown in dashed lines in the figure) obtained through the motion compensation is as shown by reference numeral A in FIG. 2, and the residual contour obtained after the motion injury between the current contour and the previous contour. (Shown as solid lines in the diagram) as shown by reference B, and if the compensated contour segment (dotted line in the solid line block in the diagram) as shown by reference mark C, the remaining contour portion remaining after motion compensation Is the contour information to be finally transmitted after encoding. Therefore, in the present invention, in inter-mode encoding, the encoding using indexing on the residual contours is performed to transmit the index information of each pixel in the MC contour information corresponding to the residual contours and the corresponding position information to the receiving side. do.

In other words, in indexing block 108 each index, e.g., sequential, for each pixel on the MC contour that is substantially motion-compensated except for the motion compensated contour segments provided from motion compensation block 106 described above. Assign a serial number of positive integers. This is because if the size of the object is not so large, it is much more efficient than coding the information on the x and y axes separately. The index information thus allocated as the serial number is then provided to the optimum point selection block 110 via line L14.

On the other hand, in the optimal point selection block 110 finds a point on the MC contour closest to the vertex information to be newly encoded in the current contour provided from the polygonal approximation block 102 described above through the line L11, and then on the line L15 Index information assigned to pixel values on the MC outline corresponding to the vertex information to be encoded is generated, and corresponding vertex information and selected point information on the MC outline corresponding thereto are generated on the line L16.

That is, as shown in FIG. 2 as an example, the optimal point selection when the newly selected vertex for encoding on the residual contour B is b _n and the point on the MC contour A closest to the vertex is a _n. In block 110, the index assigned to the point a _n , that is, the serial number is generated on the line L15 and provided to the switching circuit 116 to be described later, while the vertex b _n and the point a _n information on the line L16 Provided to the relative distance calculation block 112. Here, the switching circuit 116 switches its contacts based on the switching control signal CS1 from the control block 114 to be described later. Subsequently, the switching circuit 116 substantially controls the control from the control block 114 during inter-mode encoding. Accordingly, the index information from the optimal point selection block 110 is provided to the outline coding block 124 described later through the line L17.

In addition, in the optimal point selection block 110, when the residual contour and the MC contour obtained after the motion compensation are, for example, as shown in FIG. 2, motion compensated contour segments C and coding that do not need to be encoded. The first start point index s1, the first end point index e1 and the second start point index s2 and the second end point index e2 are generated on the line L15 to distinguish the remaining contours B to be transmitted. 116). This is so that the part of the contour segment whose motion is compensated in the decoding system on the receiving side can be known.

That is, the decoding system on the receiving side will reconstruct from the object contour information of the previous frame by using the motion vector for the motion compensated contour segments C, and the encoded residual contours B that are not motion compensated. With respect to, it will be restored to the original signal before encoding based on the index information for each point on the MC contour A and the relative position information from each point.

Next, in the relative distance calculation block 112, the distance between each vertex and the corresponding selected point based on the vertex to be encoded and the closest selected point information on the MC outline provided from the optimal point selection block 110. The distance values between the vertices and the respective points, which are continuously calculated in this way, are provided to the next control block 114 as an information source for determining the encoding mode.

Meanwhile, in the control block 114, the encoding mode is determined by comparing the distance value provided from the relative distance calculation block 112 with a preset threshold value, that is, the vertex and the corresponding MC in the control block 114. If the distance between the nearest points on the contour is greater than the preset threshold, intra mode coding is selected. If the distance is less than the preset threshold, inter mode coding is selected.

In addition, the control block 114 generates a control signal CS1 for switching in the switching circuit 116 or vertex information value currently to be encoded on the line L20 in accordance with the comparison result between the distance value and the threshold value. Is generated and provided to the vertex encoding block 122. In the case of inter-mode encoding in which the distance value between the vertex and the corresponding point is smaller than the predetermined threshold value, each distance value provided from the relative distance calculation block 112 is next. The switching control signal CS1 is generated and provided to the switching circuit 116 while being provided to the position information coding block 118 of the stage. As a result, the switching circuit 116 is turned on in accordance with the switching control signal CS1, so that index information on the line L15 is provided to the contour coding block 124 on the output side via the line L17.

On the other hand, in the position information coding block 118, the relative position information dx from the point where the index is sent based on the respective corresponding vertices and the distance values between the respective points provided from the control block 114 described above. dy is computed and occurs on line L18, i.e., as shown in FIG. 2 as an example, if a _n is determined as the closest point to vertex b _n , then position information coding block 118 is determined relative to this point. The distance d is variable length and / or fixed length coded to occur on line L18.

Therefore, in the inter mode encoding as described above, in the contour coding block 124, one motion vector and the switching circuit 116 extracted with respect to one object on the line L13 provided from the motion compensation block 106 described above are selected. An example of the relative position information values from the point at which each index information on the line L17 provided from the optimal point selection block 110 and each index on the line L18 provided from the position information encoding block 118 is sent via For example, the binary arithmetic code of the Joint Photographic Experts Group (JPEG) is used to encode the contour signal of the encoded digital image including one motion vector, an index set, and a set of position information values. It is transmitted to a transmitter not shown for transmission to the receiver.

On the other hand, when the intra-mode encoding is selected in the control block 114 because the distance value between the vertex and the corresponding point is larger than the predetermined threshold value, the switching circuit 116 is turned off according to the switching control signal CS1. In addition, the control block 114 generates vertex information to be encoded on the line L20 and provides the vertex encoding block 122. At this time, the vertex encoding block 122 is provided with the encoded vertex information immediately before the vertex to be currently encoded in the same frame from the buffer memory 120 through the line L19.

Next, the vertex encoding block 122 encodes the relative position information between the vertex encoded immediately before the current frame on the line L19 and the vertex to be currently encoded on the line L20, and occurs on the line L21. That is, as an example, as shown in FIG. 3, when the vertex on the previously encoded line L19 in the same frame is a1 and the vertex on the line L20 to be currently encoded is a2, the vertex encoding block 122 previously performs The relative position d12 between the encoded vertex a1 and the vertex a2 to be encoded is encoded and provided to the contour encoding block 124 through the line L21. In the figure, reference numeral A denotes an MC contour and B denotes a residual contour to be transmitted by encoding.

In other words, in the vertex encoding apparatus according to the present invention, in the intra mode encoding, the above-described inter mode encoding does not use index information, and instead of the vertex that is encoded immediately before in the current frame with respect to the vertex to be currently encoded. The relative position information is encoded and transmitted.

Therefore, in the intra mode encoding as described above, in the contour coding block 124, one motion vector and the vertex coding block 122 extracted with respect to one object on the line L13 provided from the motion compensation block 106 described above. For example, the binary arithmetic code of the Joint Photographic Experts Group (JPEG) can be used for the relative position information on the line L21 (relative position from a previously encoded vertex within the current frame). And a contour signal of an encoded digital image including one motion vector and a set of relative position information values is transmitted to a transmitter not shown for transmission to a remote receiver.

As described above, according to the present invention, in vertex encoding for object-based contour encoding, vertices on residual contours to be transmitted after encoding based on a distance difference value between the vertex to be currently encoded and the nearest point on the MC contour. Inter mode coding or intra mode coding is selectively applied to the inter mode coding. In the case of inter mode coding, one motion vector, a plurality of index information, and relative position information of an object (the closest point on the vertex and MC contour to be encoded) Distance information) is encoded and finally transmitted, and in the intra mode, by transmitting the final position by encoding the relative position information values from one motion vector of the object and the immediately-encoded vertex in the current frame. Amount of data While minimizing the production of the remaining contour information of the object remains after the motion compensation may appear on the video signal can be encoded effectively.

Claims (3)

An apparatus for encoding a contour of an object appearing in a digital image signal having a plurality of frames including a current frame and a previous frame using motion compensation, wherein the contour approximation of the object using a contour approximation technique that fits the contour into line segments is performed. A polygonal approximation block that performs to generate vertex information for each line segment in the current contour of the current frame; Based on previous contour information of the previous frame, one motion vector for an object is extracted through matching between the current contour and a plurality of candidate contours in the search range in the predetermined motion search range, and the extracted one. A motion compensation block for generating at least one contour segment, at least one remaining contour, and at least one MC contour without motion compensation, which are motion compensated by motion compensation between the current contour and the previous contour using the motion vector of the motion vector; An indexing block for assigning a series of index information having an integer value for each pixel point of the generated at least one MC contour; Generating respective starting point index information and ending point index information on each MC contour, searching each point on the MC contour that is closest to each vertex information on each line segment corresponding to each remaining contour, and searching each point An optimal point selection block for successively generating respective index information corresponding to each vertex information to be encoded assigned to A relative distance calculation block for calculating a distance value between each vertex to be encoded and each selected point on the MC contour corresponding thereto; A control block which compares each of the calculated distance values and a predetermined threshold value, and adaptively selects inter mode encoding or intra mode encoding for each vertex on the residual contour according to the comparison result; A position information generation block for encoding relative position information between respective vertex information on the remaining contour from each point on the MC contour based on the calculated distance values; A switching circuit for switching on / off the output of the respective index information provided from the optimum point selection block based on a switching control signal from the control block; A buffer memory provided from the polygonal approximation block and storing vertex information encoded immediately before vertex information to be currently encoded on the remaining contour in the current frame; A vertex encoding block encoding relative position information between the previous vertex and the vertex to be currently encoded provided through the control block according to control from the control block during the intra mode encoding; And encoding one motion vector of the object, each index information corresponding to each vertex information, and relative position information between the vertex information from each point in the inter mode encoding, and the intra mode. And a contour encoding means for encoding one motion vector of the object and relative position information between the previous vertex and the current vertex at the time of encoding. According to claim 1, One motion vector for the object, the current contour and a plurality of within the search range extended to a predetermined width in the motion search range of the predetermined region based on the previous contour information of the previous frame. The vertex encoding apparatus of claim 1, wherein the optimal candidate contour is detected through matching between candidate contours and is determined as a predicted contour, and the displacement is between the expanded current contour and the predicted contour. The system of claim 2, wherein the expanded current contour is along a contour boundary. Extended by 1 pixel, and the search range in the previous frame is along the previous contour boundary. The object contour coding is set to a range of 16 pixels, and the predicted contour is determined by the number of mismatched pixels calculated by matching the plurality of candidate contours in the search range of the previous frame with the extended current contour. Vertex encoding apparatus for the.