Abstract: A streaming method and apparatus, in which information regarding a plurality of chapters of content is inserted into a media presentation description that includes information regarding a plurality of media data generated by encoding the content so as to have different qualities, and then, streaming is performed based on the information.

Abstract: A method and apparatus for transmitting and receiving data are provided. In the method of receiving data, at least one of a plurality of media data generated by encoding content to have different qualities is received, the plurality of media data each including at least one segment; location information indicating a randomly accessible point of each of the at least one segment is obtained; and random accessing is provided on the received media data, based on the location information.

Abstract: A method and apparatus for reproducing media data are provided. The method includes: receiving a first file including information about a period of first content and information about a period of second content; receiving and reproducing media data of the first content based on the received first file; stopping reproducing of the media data of the first content and receiving and reproducing media data of the second content based on the first file; and receiving and reproducing the media data of the first content when the reproducing the media data of the second content is completed, wherein the information about the period of the second content includes location information about the second media data of the second content or location information of a second file including the location information about the second media data of the second content.

Abstract: A method and apparatus for performing streaming that is adaptive to a streaming environment, using information about a plurality of media data generated by encoding content to have different qualities.

Abstract: Provided are a method and apparatus for receiving and providing data. The method of receiving data includes: receiving first information including information about a first interval of a plurality of media data generated by encoding content in different qualities; acquiring renewal time information indicating a point of time for a first file to be renewed by using the first information; and receiving second information comprising information about a second interval of the plurality of media data based on the renewal time information.

Abstract: Provided are a method and apparatus for transmitting or receiving data. The method includes obtaining information about first media data, the first media data including at least one component; and obtaining the at least one component based on the information about the first media data, wherein the information about the first media data further includes information indicating whether the at least one component is provided together with a component obtained from second media data.

Abstract: A method and apparatus for adaptively transmitting and receiving media data to a streaming environment by segmenting into segments a plurality of media data, which is generated by encoding content to have different qualities.

Abstract: A method and apparatus for providing a trick play service in a hypertext transfer protocol (HTTP) adaptive streaming (HAS) architecture for adaptively streaming media data according to fluctuation of a streaming environment are provided. The method at a server includes: generating a media presentation description (MPD) file including information about at least one piece of trick play data; transmitting the MPD file to a client; and transmitting the at least one piece of trick play data to the client in response to a request by the client based on the MPD file. The method at a client includes: receiving a media presentation description (MPD) file including information about at least one piece of trick play data; and receiving the at least one piece of trick play data from a server based on the MPD file.

Abstract: A method and apparatus of improving the compression efficiency of a motion vector by efficiently predicting a motion vector in an enhancement layer from a motion vector in a base layer in a video coding method using a multi-layer are provided.

Abstract: Multi-layer video coding and decoding methods, multi-layer video encoder and multi-layer video decoder are provided. The multi-layer video coding method includes encoding a video frame having a predetermined resolution using a first video coding scheme, using a frame encoded by the first video coding scheme as a reference to encode the video frame with the same resolution as the predetermined resolution using a second video coding scheme, and generating a bitstream containing the frames encoded by the first and second video coding schemes.

Abstract: A peer-to-peer (P2P) network system is provided. The P2P network system includes a server which groups transmission unit packets constituting a data stream into a group according to a predetermined time unit and provides the group of the transmission unit packets, and a plurality of peer devices which transmit and receive the group of the transmission unit packets.

Abstract: A method and apparatus of improving the compression efficiency of a motion vector by efficiently predicting a motion vector in an enhancement layer from a motion vector in a base layer in a video coding method using a multi-layer are provided.

Abstract: Disclosed are a method and an apparatus for realizing signal to noise ratio (SNR) scalability in a video stream server in order to transmit a video stream in a variable network environment. An apparatus for adapting a bitrate of a coded scalable bit-stream based on multi-layers to a variable network environment, comprising a bit-stream parsing unit to parse an input bit-stream, a pre-decoding condition determining unit to determine a target transmission bitrate according to the variable network environment, a pre-decoding unit to skip at least one frame among the frames included in the parsed bit-stream according to the determined target transmission bitrate, and a bit-stream transmission unit to transmit to a client device the bit-stream that has been restructured due to frame skipping.

Abstract: A method and apparatus for efficiently predecoding a hybrid bitstream generated by a plurality of coding schemes are provided. The method includes obtaining a first bit-rate for a boundary between the lower layer bitstream and the upper layer bitstream and a second bit-rate for a boundary between motion information and texture information of the upper layer bitstream from the input hybrid bitstream, determining the target bit-rate according to variable network circumstances, and when the target bit-rate is between the first and second bit-rates, skipping the motion information of the upper layer bitstream and truncating all bits of the texture information of the upper layer bitstream from the tail, except bits corresponding to the difference between the target bit-rate and the first bit-rate.

Abstract: An MPEG audio encoding method, a method for determining a window type when encoding MPEG audio, a psychoacoustic modeling method when encoding MPEG audio, an MPEG audio encoding apparatus, an apparatus for determining a window type when encoding MPEG audio, and a psychoacoustic modeling apparatus in an MPEG audio encoding system are provided. The MPEG audio encoding method comprises performing modified discrete cosine transform (MDCT) on an input audio signal in a time domain; with the MDCT performed MDCT coefficients as an input, performing psychoacoustic model; and by using the result of performing the psychoacoustic model, performing quantization, and packing a bitstream. According to the method, complexity of computation can be reduced and waste of bits can be prevented.

Abstract: An interframe wavelet video coding (IWVC) method by which an average temporal distance (ATD) is minimized is provided. The IWVC method comprises receiving a group-of-frames and decomposing the group-of-frames into difference frames and first average frames between the frames in a first forward temporal direction and a backward temporal direction, wavelet-decomposing the first difference frames and the first average frames, and quantizing coefficients resulting from the wavelet-decomposition to generate a bitstream. The IWVC method provides improved video coding performance.

Abstract: An audio compression method using wavelet packet transform (WPT) in MPEG1 layer 3 (hereinafter referred to as “MP3”) and a system thereof are provided. The method comprises calculating perceptual energy by analyzing audio samples which are input based on a psychoacoustic model; according to comparison of the level of the calculated perceptual energy with a threshold, selectively determining a modified DCT (MDCT) processing window and a wavelet packet transform (WPT) processing window; by processing audio samples corresponding to the scopes of the determined windows in the MDCT and WPT, converting the audio samples into data on frequency domains; and quantizing the processed data on the frequency domains according to the number of assigned bits.

Abstract: Deblocking filter used in a video encoder/decoder based on a multilayer. In deciding a deblocking filter strength when performing a deblocking filtering with respect to a boundary between a current block coded by an intra-BL mode and its neighboring block, it is determined whether the current block or the neighboring block has coefficients. The filter strength is decided as a first filter strength if it is determined that the current block or the neighboring block has the coefficients, and the filter strength is decided as a second filter strength if it is determined that the current block or the neighboring block does not have the coefficients. The first filter strength is greater than the second filter strength.

Abstract: A method of multi-layer based scalable video encoding and decoding and an apparatus for the same are disclosed. The encoding method includes the steps of estimating motion between a base layer frame that is placed at a temporal location closest to a current frame of an enhancement layer, and a frame that is backwardly adjacent to the base layer frame to acquire a motion vector, generating a residual image by subtracting the backwardly adjacent frame from the base layer frame, generating a virtual forward reference frame using the motion vector, the residual image and the base layer frame, and generating a predicted frame with respect to the current frame using the virtual forward reference frame, and encoding the difference between the current frame and the predicted frame.

Abstract: A deblocking filter used in a video encoder/decoder based on a multilayer is disclosed. The deblocking filtering method includes choosing a present block and its neighboring block on which a deblocking filtering will be performed, judging whether the present block and the neighboring block have been coded by the intra BL mode, choosing a deblocking filter strength according to the result of the judgment, and performing the deblocking filtering with respect to a boundary between the present block and the neighboring block and according to the deblocking filter strength.