Abstract: According to an aspect of embodiments, a method of generating an image by using LiDAR includes performing a reconstruction of a two-dimensional reflection intensity image, the performing of the reconstruction including projecting three-dimensional reflection intensity data that are measured by using the LiDAR as the two-dimensional reflection intensity image, and the method includes generating a color image by applying a projected two-dimensional reflection intensity image to a Fully Convolutional Network (FCN).

Abstract: According to an aspect of embodiments, a method of generating an image by using LiDAR includes performing a reconstruction of a two-dimensional reflection intensity image, the performing of the reconstruction including projecting three-dimensional reflection intensity data that are measured by using the LiDAR as the two-dimensional reflection intensity image, and the method includes generating a color image by applying a projected two-dimensional reflection intensity image to a Fully Convolutional Network (FCN).

Abstract: A transcoding method and apparatus for converting a digital bitstream complying with a certain compression method into a digital bitstream complying with a different (or the same) compression method is provided. The transcoding apparatus performs conversion between compressed bitstreams having at least syntax elements and video elements corresponding to video data.

Abstract: A mapper-based variable length coding method and decoding method and apparatuses therefor are provided. The mapper-based variable length coding method includes an inputting step for receiving symbol data to be coded and receiving element type information on the kind of symbol data, a coding step for generating a first code number corresponding to the received symbol data, a mapping step for selecting a second code number mapped with respect to selected element type information in mapping tables formed of second code numbers, each of which is appropriately mapped according to the first code number and the element type information, a codeword extracting step for generating a codeword corresponding to the selected second code number, and an outputting step for outputting the generated codeword. According to the methods and apparatuses, the advantages of a universal variable length code table can be maintained while preventing efficiency lowering of compression coding.

Abstract: A variable length coding method and apparatus is provided. The variable length coding method includes the steps of (a) selecting predetermined macroblocks from among the previous macroblocks of a macroblock to be coded in a current frame, (b) analyzing the occurrence statistics of symbols with respect to the selected macroblocks, (c) resetting a mapping relationship based on the analyzed occurrence statistics of symbols, and (d) variable length coding a current macroblock based on the reset mapping relationship. The variable length coding method dynamically varies the mapping relationship between symbols and bit patterns based on the occurrence statistics of the symbols, thereby reducing the amount of bits generated when coding images of the same picture quality.

Abstract: A motion vector coding method is provided. The motion vector coding method includes the steps of (a) performing an affine motion estimation to obtain affine motion parameters, (b) converting the affine motion parameters to a predetermined number of translational motion vectors, and (c) coding the difference between the converted translational motion vectors of a current block and the converted translational motion vectors of a previous block. The method allows for low bit generation while maintaining motion estimation performance available from affine motion estimation.

Abstract: Video coding and decoding methods. The video coding method includes: receiving channel status information indicating an error profile of the communication channel; and adaptively adding redundancy information into data packets divided by syntax with a layer configuration, based on the channel status information. The video decoding method includes: receiving an encoded video bitstream; identifying whether an additional layer is present and which layer has been added; and decoding corresponding layers based on the information about the additional layer. The video coding and decoding methods can be implemented in a video coder-decoder (CODEC) to avoid erroneous decoding in an error-prone channel, thus improving error-resilience of the CODEC.

Abstract: A motion vector coding method is provided. The motion vector coding method includes the steps of (a) performing an affine motion estimation to obtain affine motion parameters, (b) converting the affine motion parameters to a predetermined number of translational motion vectors, and (c) coding the difference between the converted translational motion vectors of a current block and the converted translational motion vectors of a previous block. The method allows for low bit generation while maintaining motion estimation performance available from affine motion estimation.

Abstract: A variable length coding method and apparatus is provided. The variable length coding method includes the steps of analyzing the occurrence statistics of symbols with respect to previous frames, generating a mapping table for variably mapping input symbols to bit patterns based on the analyzed occurrence statistics of the input symbols, resetting the mapping relationship between symbols and bit patterns based on the generated mapping table, and variable length coding a current frame based on the reset mapping relationship. The variable length coding method efficiently reduces the number of bits generated by dynamically varying the mapping between input symbols and bit patterns depending on the occurrence statistics of the input symbols.

Abstract: A video data transmitting device for discriminatively protecting compressed video data from errors according to the significance of the data and for transmitting the video data, and a video data receiving device for decompressing video data transmitted by the transmitting device, are provided. The video data transmitting device includes a compression portion for discriminating the significance of the video data, generating region information classified by regions, compressing the video data by regions according to the region information, and outputting compressed video data, and a coding portion for receiving the region information and the compressed video data, coding the compressed video data by regions according to a predetermined coding rule corresponding to the significance included in the region information using the RCPC coding method, inserting a predetermined marker into the coded data, and outputting channel-coded video data via a communications channel.

Abstract: A method and an apparatus for transmitting and recovering a video signal are provided. The method for transmitting a video signal that has a hierarchical structure of a frame, groups of blocks (GOBs), and macro blocks includes a transmitter inserting a plurality of resynchronization markers into each GOB to prevent the propagation of errors generated in a transmission channel. The insertion of the resynchronization markers includes assigning the number of resynchronization markers to the respective GOBs and inserting the assigned resynchronization markers into predetermined positions of the corresponding GOB. The positions are determined to minimize the mean error propagation cost based on whether respective macro blocks positioned between the resynchronization markers to be inserted are skipped. The present invention make it possible to prevent the propagation of an error when a video signal is transmitted over an error prone mobile network or radio network.

Abstract: A transcoding method and apparatus for converting a digital bitstream complying with a certain compression method into a digital bitstream complying with a different (or the same) compression method is provided. The transcoding apparatus performs conversion between compressed bitstreams having at least syntax elements and video elements corresponding to video data.

Abstract: A motion vector coding method is provided. The motion vector coding method includes the steps of (a) performing an affine motion estimation to obtain affine motion parameters, (b) converting the affine motion parameters to a predetermined number of translational motion vectors, and (c) coding the difference between the converted translational motion vectors of a current block and the converted translational motion vectors of a previous block. The method allows for low bit generation while maintaining motion estimation performance available from affine motion estimation.

Abstract: A mapper-based variable length coding method and decoding method and apparatuses therefor are provided. The mapper-based variable length coding method includes an inputting step for receiving symbol data to be coded and receiving element type information on the kind of symbol data, a coding step for generating a first code number corresponding to the received symbol data, a mapping step for selecting a second code number mapped with respect to selected element type information in mapping tables formed of second code numbers, each of which is appropriately mapped according to the first code number and the element type information, a codeword extracting step for generating a codeword corresponding to the selected second code number, and an outputting step for outputting the generated codeword. According to the methods and apparatuses, the advantages of a universal variable length code table can be maintained while preventing efficiency lowering of compression coding.