Abstract: The present invention relates to a method for transmitting a packet in a communication system, the method comprising: generating drop information indicating at least one source packet to be dropped among source packets to be transmitted and whether or not to drop each of the other source packets except the at least one source packet; performing forward error correction (FEC) encoding on the drop information and the other source packets except the at least one source packet; generating a repair packet comprising repair data for restoring the drop information and a repair symbol for restoring the other source packets except the at least one source packet; and transmitting the other source packets except the at least one source packet and the repair packet.

Abstract: The present invention relates to a device and method for transmitting or receiving media resource identification (MRI) information for managing traffic of a service in a communication system. A method for transmitting information associated with content provision in a communication system according to an embodiment of the present invention comprises the steps of: acquiring content configuration information and transmission scheme information for a content; generating media resource identification information including scheduling information and the transmission scheme information according to each content type on the basis of the content configuration information and the transmission scheme information; and transmitting the media resource identification information.

Abstract: A method of a transmission device in a multimedia system comprises the steps of: detecting a request for changing first-type data into second-type data while the first-type data is being played at a given point in time; and transmitting, before the second-type data is played, information necessary for replaying data, among the first-type data, played prior to the given point in time, and/or data, among the second-type data, played prior to the given point in time.

Abstract: Provided are a transmitting apparatus, a receiving apparatus and controlling methods thereof. The transmitting apparatus includes: at least one processor configured to implement a packet generator which generates a packet including a header and a payload based on a plurality of input packets; and a signal processor which signal-processes the generated packet, and a transmitter configured to transmit the signal-processed packet. A base field included in the header includes a first field set to a first value representing that the base field is a first length or a second value representing that the base field is a second length.

Abstract: A transmitting apparatus, a receiving apparatus, and a method of signal processing are provided. The transmitting apparatus includes at least one processor configured to implement: a packet generator which generates a packet including a header and a payload, based on an input stream; and a signal processor which signal-processes the generated packet. The header includes a base header, and the base header includes various fields indicating at least one of a packet type, and a value indicating that the packet transmits one single complete input packet, a segment of an input packet, or a plurality of input packets. The fields included in the base header may also indicate presence of an additional header and a substream identifier.

Abstract: A method of a transmission device in a multimedia system comprises the steps of: detecting a request for changing first-type data into second-type data while the first-type data is being played at a given point in time; and transmitting, before the second-type data is played, information necessary for replaying data, among the first-type data, played prior to the given point in time, and/or data, among the second-type data, played prior to the given point in time.

Abstract: A transmission device is disclosed. The transmission device comprises a signal generation unit for generating a broadcast signal including a service, and a transmission unit for transmitting the broadcast signal through at least one radio frequency (RF) channel. A broadcast stream transmitted through the RF channel includes signaling for the service, the signaling for the service including information indicating whether the service is transmitted through a plurality of RF channels, and information indicating whether the broadcast stream transmitted through the RF channel contains an essential portion of the service.

Abstract: An apparatus is provided for channel encoding in a communication system using an LDPC code. The apparatus includes at least one processor configured to encode input bits using a Bose-Chaudhuri-Hocquenghem (BCH) code, shorten one or more bits of the encoded input bits according to a number of bit groups to be shortened and an order among a plurality of orders according to which the bit groups are shortened, wherein the number of bit groups to be shortened is based on a number of bits to be shortened which is based on a number of the encoded input bits, encode information bits including the encoded input bits and the shortened one or more bits, using an LDPC code to generate parity bits, and puncture one or more bits in the parity bits based on a puncturing parameter among puncturing parameters; and a transmitter configured to transmit a signal that is generated from the encoded information bits based on the punctured one or more bits.

Abstract: The present invention relates to a method for transmitting a packet in a communication system, the method comprising: generating drop information indicating at least one source packet to be dropped among source packets to be transmitted and whether or not to drop each of the other source packets except the at least one source packet; performing forward error correction (FEC) encoding on the drop information and the other source packets except the at least one source packet; generating a repair packet comprising repair data for restoring the drop information and a repair symbol for restoring the other source packets except the at least one source packet; and transmitting the other source packets except the at least one source packet and the repair packet.

Abstract: Apparatuses for transmitting and receiving a signal in a communication system are provided. An apparatus of a receive device includes a receiver configured to receive, from a transmit device, a signal comprising remaining bits of parity bits after puncturing, wherein the parity bits are obtained by adding at least one shortened bit to information bits to obtain input bits for an encoding, if a number of the information bits is less than a number of the input bits for the encoding; and a hardware processor configured to determine a number of puncture bits for the parity bits, generate an output signal by adding at least one value corresponding to the number of the puncture bits to the signal, and decode the output signal.

Abstract: The present disclosure relates to a method of transmitting multimedia content in a broadcast communication system, and comprises the steps of: identifying protocol information mapped for each service corresponding to multimedia content; transmitting service-related information including the identified protocol information mapped for each service; and transmitting multimedia content corresponding to related services to a receiving side by using the identified protocol.

Abstract: The present invention relates to a method for transmitting a packet in a communication system, the method comprising: generating drop information indicating at least one source packet to be dropped among source packets to be transmitted and whether or not to drop each of the other source packets except the at least one source packet; performing forward error correction (FEC) encoding on the drop information and the other source packets except the at least one source packet; generating a repair packet comprising repair data for restoring the drop information and a repair symbol for restoring the other source packets except the at least one source packet; and transmitting the other source packets except the at least one source packet and the repair packet.

Abstract: A method for providing a broadcast service is provided. The method includes transmitting a user datagram protocol (UDP)/internet protocol (IP) packet including a first message, the first message containing information about a message to be signed and transmitted, and transmitting a moving picture experts group (MPEG) media transport protocol (MMTP) packet including a second message, the second message containing information about the broadcast service and information indicating whether the information about the broadcast service is signed. The first message includes an identifier of a key used to verify a signature of the message to be transmitted and signed and an identifier of a hash algorithm used to calculate a hash value of the message to be transmitted and signed.

Abstract: The present disclosure provides a data transmission method of a system in an IP based broadcasting network, the data transmission method comprising the steps of: generating an MPEG media transport protocol (MMTP) packet using a media processing unit (MPU) for a service; generating an IP packet using the MMTP packet; generating a layer 2 (L2) packet using the IP packet and generating a layer 1 (L1) packet stream using the L2 packet; and transmitting the L1 packet stream, wherein absolute time information of the system is included in one of a transmission frame of the L1 packet stream and the L2 packet.

Abstract: Provided is a method for supporting an immersive media service by a media transmission device. The method comprises the steps of: determining at least one space among a plurality of spaces of interest (SOI) based on SOI description information; and transmitting, to a media reception apparatus, partial SOI description information among the SOI description information and partial immersive media data among immersive media data, wherein the partial SOI description and the partial immersive media data corresponds to the determined at least one SOI, wherein the partial SOI description information includes at least one of identification information for the at least one SOI, a space range indicator for an object of interest (OOI), a priority indicator for the OOI, or an object vector for the OOI.

Abstract: A transmitting apparatus, a receiving apparatus and methods of controlling these apparatuses are provided. The transmitting apparatus includes: a baseband packet generator configured to, based on an input stream including a first type stream and a second type stream, generate a baseband packet including a header and payload data corresponding to the first type stream; a frame generator configured to generate a frame including the baseband packet; a signal processor configured to perform signal-processing on the generated frame; and a transmitter configured to transmit the signal-processed frame, wherein the header includes a type of the payload data in the baseband packet and the number of the first type stream packets in the baseband packet.

Abstract: A transmitting apparatus is provided. The transmitting apparatus includes: a baseband packet (BBP) generator configured to generate a BBP including a header and payload data; a frame generator configured to generate a frame including the BBP; a signal processor configured to signal-process the generated frame; and a transmitter configured to transmit the signal-processed frame. The header includes information about a type of the payload data, whether an additional header exists, a length of the payload data, and a Least Significant Bit (LSB) of the length of the payload data. Therefore, various types of data are mapped on a physical layer based on information included in the header, and data processing efficiency is improved.

Abstract: A method for providing a multimedia service based on unicast, according to the present invention, comprises the steps of: packetizing multimedia data; when a terminal accesses the multimedia service, determining a mode for transmitting the multimedia data to the terminal; generating a signaling message including information on the determined mode, and transmitting the signaling message to the terminal; and transmitting first data among the packetized multimedia data to the terminal on the basis of the determined mode.

Abstract: The present invention relates to a method and device for transmitting or receiving a broadcast service including a packet, which is generated using an application layer forward error correction (AL-FEC) scheme, in a multimedia service system. An embodiment of the present invention provides a method for transmitting a broadcast service by a transmitter, the method comprising the steps of: determining one forward error correction (FEC) scheme for a broadcast service among multiple FEC schemes; configuring a signaling message so as to include an identifier indicating the determined FEC scheme; and transmitting the configured signaling message.

Abstract: A method for transmitting multimedia according to the present disclosure comprises: a step of transmitting a first message including fixed delay information and buffer information with respect to a receiving device; and a step of transmitting a packet relating to the multimedia and including a transmission time stamp, wherein a first packet is sent out from a digital buffer of the receiving device at a time determined by adding up the transmission time stamp and the fixed delay information.