Abstract: A transcoding apparatus and associated methodology of transcoding a first video stream into a second video stream, is provided. A separator extracts a video transport stream packet including the first video stream, a non-video transport stream packet, and timing information from a first transport stream. The timing information indicates a time at which the non-video transport stream packet is formed and the first transport stream relative to the video transport stream packet. A memory is provided to store the timing information. A conversion unit generates the second video stream based on the first video stream. A multiplexer multiplexes a converted video transport stream packed including the second video stream and a converted non-video transport stream packet based on the stored timing information to generate a second transport stream, including the second video stream.

Abstract: Disclosed is a digital video record/playback apparatus and playback method thereof, by which a trick play mode of a digital video stream is processed. In the present invention, the transport stream is stored without additional data, the index information extracted in the storing process includes picture type, location of PCR packet of the corresponding picture, record location of the corresponding picture, etc., and the decoding time point of the picture is determined to display the corresponding picture by appropriately adjusting the transmission bit rate and the status of the VBV buffer according to the trick play mode in playing back the digital video stream. Therefore, without additional appended devices and a series of processing, the present invention enables to implement the trick play of the user-selected direction and speed and to reduce costs.

Abstract: A method of decoding audio data, encoded in multiple DIF blocks in a Digital Video (DV) data stream, and outputting said audio data as a PCM frame, includes fetching a single Digital Interface Frame (DIF) block from the DV data stream. A first byte in the single DIF block is de-shuffled to determine its index (n) in the PCM frame. Each byte in the in the single DIF block is de-shuffled to determine its respective index (n) in the PCM frame. The de-shuffled data is written into the PCM frame for output if the present DIF block is the last in the present DV frame. Subsequent DIF blocks in the DV frame are processed in the manner described above.

Abstract: An IP network includes a central entity and at least one customer premises equipment (CPE) device. The central entity generates a program clock reference (PCR) clock and provides audio-visual packets to a CPE based on the PCR clock. The CPE sets a first clock based on the PCR clock for decoding operations. The CPE sets a second clock that is independent from the first clock for audio and video output operations. For example, the CPE can process the audio-visual packets using the second clock.

Abstract: A method and system for efficiently delivering messages from a service provider to individual receiving devices in a unidirectional, multi-channel communications system that provides parallel distribution of information from the service provider to the receiving devices. The messages are transferred from the service provider to the receiving device only on an agreed-upon channel at an agreed-upon time, wherein each message is tagged with an address corresponding to the receiving device by the service provider and then transmitted by the service provider to the receiving device on the agreed-upon channel with the receiving device filtering the agreed-upon channel to detect the address and decode its messages. The agreed-upon channel and the agreed-upon time of message transfers are coordinated between the service provider and the receiving device prior to transferring the message from the service provider to the receiving device.

Abstract: Techniques are provided for re-mapping and interleaving transport packets of multiple transport streams for processing by a single transport demultiplexor. At least one PID re-map table is employed having re-map values indexed by n possible PID values of transport packets associated with at one transport stream of the multiple transport streams. The n possible PID values is less than or equal to the number of PID values which can be handled by the single transport demultiplexor, and is less than all possible PID values of transport packets within the multiple transport streams. The PID values within at least one transport stream are compared with the n possible PID values of the PID re-map table, and when a match is found, the table is indexed using the matching entry and a re-map value is generated therefrom. The re-map value replaces the original PID value within the transport packet.

Abstract: A method of processing a digital television (DTV) signal is disclosed. Herein, the DTV signal is generated by performing Reed-Solomon (RS) encoding on additional data, multiplexing the RS-encoded additional data with main data. RS encoding the multiplexed additional and main data, interleaving the RS-encoded additional and main data, trellis encoding the interleaved additional and main data, and transmitting a Radio Frequency (RF) DTV signal including the trellis-encoded additional and main data. The method to process the DTV signal includes receiving the DTV signal including the additional data multiplexed with the main data through an antenna, in which signaling information is periodically inserted in the additional data. The received DIV signal is demodulated including performing channel equalization on the demodulated DTV signal. Trellis decoding is performed on the channel-equalized DIV signal.

Abstract: A method of reproducing multimedia contents in a mobile communication environment is provided. The method comprises configuring a first mobile terminal connected to at least a second mobile terminal in a communication network to download a content file from a remote content server; synchronizing the first mobile terminal with the second mobile terminal to download the content file in at least first and second segments; and downloading the first segment to the first mobile terminal and the second segment to the second mobile terminal.

Abstract: A method and apparatus are provided for the dynamic multiplexing of digital streams which are transmitted in the form of stream units in one channel, each of said stream units bearing a stream identifier which can be used to associate same with the corresponding digital stream. The allocation of an identifier to a digital stream is defined by an allocation table and can vary over time, in such a way as to enable dynamic multiplexing. The aforementioned allocation table bears a version number and, in order to indicate that a change in the version of the allocation table applies to a given digital stream, a burst is transmitted with at least one version change stream unit comprising the current identifier of said digital stream, an indicator which can be used to determine if the stream unit is a version change stream unit and the version number becoming applicable to said digital stream.

Abstract: An entire stream containing a plurality of partial streams each consisting of content information is multiple-recorded on packet basis on an information recording medium. The information recording medium includes a file for storing object data consisting of a plurality of packets each containing a content information piece and further includes a file for storing information defining a reproduction sequence of object data and information indicating discontinuity of continuous numbers caused by absence of a packet during edition of continuous numbers of a plurality of packets corresponding to the recording order during multiple recording.

Abstract: On an information recording medium, an entire stream including a plurality of portion streams, each of which is provided with content information, is multiplexed-and-recorded by a unit of packet. The information recording medium is provided with a file for storing object data, which is provided with a plurality of packets, each of which stores therein a piece of the content information. The information recording medium is further provided with a file for storing information which defines a reproduction sequence of the object data and a file for storing information for indicating a discontinuous condition of a serial number of the plurality of packets corresponding to a recording order upon multiplexing-and-recording. The discontinuous condition is generated by a lack of the packet upon editing, with respect to the serial number.

Abstract: A method is provided for transmitting a plurality of informational video programs over a single digital transport stream to a plurality of receivers, wherein the receivers are operative to select from the transport stream data identified with any given program and to decode the identified data into a displayable video signal.

Abstract: The invention relates to a system and method for the generation of television channels and which allows the generation of the same by the processing and selection of designated packets of data from multiple data transport streams, which each transport stream including numerous packets of data. In each transport stream the packet of data is identified by the allocations of a packet identification code (PID) and each is held in the transport packet which is transmitted as part of each transport stream. In accordance with the invention, and in order to prevent errors and inaccurate packet selection, a Transport Stream Identification Code (TSID) is allocated to each of the transport streams of data received. Typically the TSID is located in the transport packet for each transport stream of data. In the selection of a packet of data, the appropriate TSID is referred to identify the appropriate transport stream and the PID then referred to identify the packet of data from that transport stream.

Abstract: A method and apparatus for distributed load multiplexing of multiple encoded signals over a shared communication path include processing that begins by receiving a 1st encoded signal having a 1st varying relative bit rate. The processing continues by receiving a 2nd encoded signal having a 2nd varying relative bit rate. For example, the 1st and 2nd encoded signals may be an MPEG encoded signal including a plurality of I frames, B frames and P frames. The processing continues by aligning multiplexing of the 1st and 2nd encoded signals based on reducing cumulative peak bit rates of the 1st varying relative bit rate and the 2nd varying relative bit rate. For example, the 2nd encoded signal may be delayed via buffering to ensure that the I frames of the 1st and 2nd encoded signals are misaligned.

Abstract: An editing of a video signal and an audio signal time-shared multiplex compressed by an MPEG-2 transport method designates a dividing position of the video signal at a boundary of video TS packets constituting a GOP, constructing a stream in front of said designated dividing position so as to include all audio TS packets corresponding to video TS packets present in the stream, overwriting a video TS packet, not having a corresponding audio TS packet in the stream, with a dummy TS packet, and overwriting, in a stream behind said designated dividing position, an audio TS packet with a dummy TS packet until an audio TS packet, coinciding with a reproducing timing of a video TS packet at said dividing position, appears. Thus a defective data reproduction resulting from a discontinuity in the data structure of audio frame before and after the dividing position can be avoided.

Abstract: A data broadcasting system is provided which is capable of achieving display intended and desired by a provider of data broadcasting contents. The data broadcasting system includes a transmitting system and a receiver. The transmitting system includes an HD (High Definition)/SD (Standard Definition) converting section to convert HDTV (High Definition Television) data contents into data contents having a resolution applicable to an SDTV (Standard Definition Television) monitor to obtain SDTV data contents and a multiplexing section to multiplex the SDTV data contents, HDTV video contents, and HDTV data contents.

Abstract: A method and apparatus are provided for editing video sequences.

Abstract: For conversion of a first video signal into a second video signal of a different format, a second auxiliary data packet is generated from a header carrying location data for multiplexing a first auxiliary data packet and main data of a first auxiliary data packet in the first video signal, and is multiplexed with the second video signal. For conversion from the second video signal into the first video signal, the first auxiliary data packet is generated from the header and the main data of the second auxiliary data packet, and multiplexed at the location determined by the location data in the first video signal.

Abstract: Systems and methods are described that desynchronize a video to be protected, thereby creating one or more digitally fingerprinted videos. In one implementation, a video to be protected is temporally desynchronized and spatially desynchronized. A fingerprinted copy of the video, as modified by the temporal and spatial desynchronizations, is created.

Abstract: A data processing apparatus constituting a low-cost audio/video data transmission and reception system is disclosed. A reception buffer monitoring circuit 21 monitors the size of receiver data being accumulated in a reception buffer 6. When the size of accumulated data is found to become higher than a high threshold, the circuit 21 causes a reception clock generation circuit 8 to generate a reception clock with a higher frequency. When the accumulated data size becomes lower than a low threshold, the reception clock is generated with a lower frequency. Based on the reception clock fed from the reception clock generation circuit 8, an audio/video decoder 7 decodes the audio/video data coming from the reception buffer 6. This invention applies advantageously to a television transmission and reception system for transmitting and receiving TV broadcast signals.

Abstract: In a recording medium storing MPEG stream, flag information (encode_condition) indicating that the stream is recorded in a format enabling easily the first stream (MPEG transport stream) to be converted into the second stream (MPEG program stream) is provided. Such a flag information is included in Tip packet which is a control packet, in the medium. Thus it can easily determine whether the data is recorded in this format without analysis of data stored in the recording medium.

Abstract: A system for use with a speaker providing audio and video in conjunction with images being provided by a podium computer responsive to the speaker as part of a live multimedia presentation. A device provides video signals and audio signals wherein the video signals correspond to the video provided by the speaker and the audio signals correspond to the audio provided by the speaker. A transmitter transmits a signal corresponding to a timing of images occurring simultaneously with the video and audio. A receiver receives the transmitted signal. A video channel converts the video signal into a digital video signal. An audio channel converts the audio signal into a digital audio signal. A receiver channel responsive to the receiver provides a timing signal corresponding to the transmitted signal and representing a timing of the images relative to the video and the audio.

Abstract: Image data is encoded using a buffer memory, and code amount of image data occupying the buffer memory upon coding is detected and buffer information related to the detected code amount is outputted. The coded image data and the buffer information are recorded on a recording medium. In a case where additional recording or overwriting is started, the buffer information in a position immediately before a start position of the additional recording or overwriting is read out, and coding is started based on value, thereby buffer overflow can be prevented.

Abstract: The audio-video synchronization process ensures continuity of displayed AV data. To initialize the process, a transport processor determines whether an occupancy criterion of a buffer storing received audio and video frames has been met. If the criterion is met, the transport processor obtains an initial time stamp value from an initial frame, and a subsequent time stamp value from a subsequent frame. Initial and subsequent parameters are computed from these respective time stamp values, and are compared against each other. If the parameters coincide, the frame is valid, and corresponding audio or video frames may be decoded and displayed. If the parameters do not coincide, a recovery process is initiated. In either event, the invention makes it possible to achieve audio-video synchronization for both live and playback modes of a digital video recorder (DVR).

Abstract: Disclosed is a serial data conversion apparatus comprising: a video signal packet conversion unit for converting a characteristic signal of a video signal into a video signal characteristic packet and simultaneously converting a video signal into a video signal packet by the characteristic signal of a video signal, horizontal/vertical synchronization signals, and a video clock signal; an audio signal packet conversion unit for converting a characteristic signal of an audio signal into an audio signal characteristic packet and simultaneously converting an audio signal into an audio signal packet by the characteristic signal of an audio signal, left/right control signals, and an audio clock signal; a control signal packet conversion unit for converting a control signal into a control signal packet by an informing signal which informs a generation of a control signal; and a multiplexer for switching and selecting the video signal characteristic packet, the video signal packet, the audio signal characteristic pac

Abstract: For encoding externally input AV signal to MPEG-TS that enables quickly conversion from MPEG-TS to MPEG-PS, data unit (Multiplexing Unit) is defined which includes a plurality of packet and has data size corresponding to data amount of one pack in MPEG-PS, and MPEG-TS is encoded for each defined data unit. Furthermore, time stamp information (ATS) added to a packet of MPEG-TS which is converted to MPEG-PS and time stamp information (SCR) added to a packet of the converted MPEG-PS are correlated with a predetermined formula.

Abstract: A communication system including a transmitter, a receiver, and a serial link, in which encoded data (e.g., encoded video data and encoded auxiliary data) are transmitted from the transmitter to the receiver. The serial link can but need not be a TMDS or TMDS-like link. In typical embodiments, alternating bursts of encoded video data and encoded auxiliary data are transmitted over each of one or more channels of the link. Other aspects of the invention are transmitters for use in encoding data for transmission over a serial link, and methods for sending encoded data over a serial link. In accordance with the invention, the data to be transmitted are encoded using a subset (sometimes referred to as a selected set of code words) of a full set of code words.

Abstract: According to one embodiment of the present invention, a novel method and system are disclosed. In one embodiment, a first node records a first node local time of receiving a wirelessly transmitted packet, the first node local time recorded with a monotonically increasing clock of the first node. The first node wirelessly transmits the recorded local time to at least a second node. The second node records a second node local time of receiving the wirelessly transmitted packet and records the first node local time of receiving the wirelessly transmitted packet. The second node updates a second node timing model to synchronize with the first node, the updating based on the second node local time of receiving the wirelessly transmitted packet and the first node local time of receiving the wirelessly transmitted packet.

Abstract: An apparatus and method for continuous synchronization of a pair of independently clocked asynchronous data streams (100, 101) consisting of raster data from independent imaging acquisition systems comprises a means for acquiring individual rasters from a first stream of data. A counter for counting (60) a first total number of received rasters and data merge logic (65) for comparing the first total to a first threshold. A means for acquiring individual rasters from a second stream of data. A means for transferring the first acquired data stream and the second acquired data stream to a composite output when the first total is greater than the first threshold. The method includes adding or subtracting idle pixels from an interline gap.

Abstract: A multiplexed data producing apparatus which multiplexes N (integer) pieces of object data in which one of video data, audio data, and digital data is multiplexed to produce one piece of multiplexed data comprises a temporal storage means for temporarily storing the N pieces of object data; a control means for controlling synchronization of time information of each object data for each temporarily stored object data; and a multiplexing means for multiplexing the processed object data to produce multiplexed data.

Abstract: In preferred embodiments, a system including a transmitter, a receiver, and a serial link, in which the transmitter is configured to transmit video data, embedded-clock auxiliary data (or auxiliary data derived from embedded-clock auxiliary data), and a video clock over the link to the receiver. The transmitter is configured to extract a sample clock from the auxiliary data without use of a phase-locked loop, and to generate time stamp data in response to the sample clock and the video clock. Typically, the auxiliary data are SPDIF (or other) audio data, and the sample clock changes state in response to codes that occur periodically in the audio data. Other aspects of the invention are a transmitter for use in such a system, a time stamp data generation circuit for use in such a transmitter, and a method for generating time stamp data in response to a stream of embedded-clock auxiliary data and a video clock.

Abstract: Systems and methods that manipulate a system time clock in an audio decoding system and/or a video decoding system are disclosed. In one example, the method may include the steps of selecting a trick mode rate and adjusting system time clock update rate as a function of the selected trick mode rate.

Abstract: According to one embodiment, a Programmable Video Recorder (PVR) receives streaming multimedia data from a data source and stores the multimedia data in a backing store. Prior to being stored, the multimedia data is assigned Presentation TimeStamps (PTS)s according to a capture graph clock that is associated with the PVR. Thereafter, system clock times that correspond with the times in which each data packet is read from the backing store are compared with the corresponding PTSs of each data packet to generate a clock scaling value that is used to slave the system clock with the capture graph clock. The clock scaling value may include the average of a plurality of scaling values that are calculated during a predetermined duration of time corresponding with the most recently read data packets.

Abstract: A method and apparatus for controlling buffering of an audio stream so that audio can be played continuously without stoppage using a minimum amount of buffering are provided. The method for controlling buffering of data includes (a) determining a buffering period of compressed audio data on the basis of a time stamp which corresponds to a packet division unit, by considering the state of a network, (b) calculating a time period where the compressed audio data is to be stored in a buffer, on the basis of the buffering period that is determined in step (a), (c) buffering the inputted compressed audio data in a decoding buffer for the time period that is calculated in step (b), and (d) decoding the compressed audio data that is stored in the decoding buffer when the time period passes in step (c) and storing the decoded audio data in a composition buffer for synchronization with video data.

Abstract: The present invention is relative to a video signal transmitting/receiving system in which digital video signals are transmitted from a transmitter (30) to a receiver (50) using a line (9) as a transmission channel. The transmitter (30) converts the video signals to be transmitted to a bit string longer in data length than a pixel making up the video signals, allocates a plural number of the bit strings to a blanking period during which pixel data in the pixel string is not transmitted and, using these bit strings, transmits the same superposed data a plural number of times. The receiver (50) extracts the specified bit strings indicating the blanking period from the received data and performs majority processing on the results of demodulation of the extracted bit strings to decide on output data. This reduces errors in reception of supplementary data to simplify the circuit structure as well as to ameliorate the error rate.

Abstract: A method is provided for transmitting a plurality of informational video programs over a single digital transport stream to a plurality of receivers, wherein the receivers are operative to select from the transport stream data identified with any given program and to decode the identified data into a displayable video signal.

Abstract: There is disclosed an information processing apparatus/method comprises inputting variable length packet data including packet length information indicative of a packet length and encoded information data, and identification flag information for identifying the packet length information, distinguishing the packet length information included in the packet data in accordance with the identification flag information and judging the packet length of the packet data, and generating the variable length packet data into fixed length packet data in accordance with the judgment result and transmitting the fixed length packet data.

Abstract: An audio/video system (100) is capable of introducing variable amounts of delay into a signal path so as to properly synchronize two signals, such a video signal and a corresponding audio signal. According to an exemplary embodiment, the audio/video system (100) includes first circuitry (50) for applying a first delay to a first digital signal. Second circuitry (80) applies a variable second delay to a second digital signal to time align the second digital signal relative to the first digital signal. The second circuitry (80) includes an addressable memory (84) for selectively storing the second digital signal and for outputting the second digital signal on a first-in, first-out basis to apply the variable second delay to the second digital signal.

Abstract: A method and apparatus for synchronizing audio and video portions of a media program signal is disclosed. The method comprises the steps of detecting an audio event in the audio portion of the media program signal, measuring the timing interval from the audio event to a subsequent video synchronization pulse in the video portion of the media program signal, and storing the timing interval in a third portion of the media program signal. The apparatus comprises a voice detector for detecting an audio event in the audio portion of the media program signal, a timer for measuring the timing interval from the audio event to a subsequent video synchronization pulse in the video portion of the media program signal, and a processor for storing the timing interval in a third portion of the media program signal.

Abstract: As information to be processed at an object-based video or audio-visual (AV) terminal, an object-oriented bitstream includes objects, composition information, and scene demarcation information. Such bitstream structure allows on-line editing, e.g. cut and paste, insertion/deletion, grouping, and special effects. In the interest of ease of editing, AV objects and their composition information are transmitted or accessed on separate logical channels (LCs). Objects which have a lifetime in the decoder beyond their initial presentation time are cached for reuse until a selected expiration time. The system includes a de-multiplexer (1), a controller (2) which controls the operation of the AV terminal, input buffers (3), AV objects decoders (4), buffers (4?) for decoded data, a composer (5), a display (6), and an object cache (7).

Abstract: A system (20) for decoding a data stream allocated into data packets contains a control unit (54), a stream demultiplexer (26), audio and video decoders (38 and 40), a memory management unit (60), and audio and video input and output buffers. Upon demultiplexing and depacketizing the data packets without interrupting the control unit, the demultiplexer sends encoded audio and video data to the audio and video input buffers. Video messages dealing with video timing information and identifying where encoded video data is stored in the video input buffer are furnished by the demultiplexer for use by the control unit. Utilizing corresponding video instructions provided from the control unit, the video decoder decodes encoded video data to produce decoded video data supplied to the video output buffer. The audio decoder decodes encoded audio data to produce decoded audio data supplied to the audio output buffer. The memory management unit controls transfer of decoded audio data to and from the audio output buffer.

Abstract: In an image transmission method of the first embodiment, as shown in FIG. 1, when compressed image data Dv obtained by compressively coding digital image data corresponding to a moving picture is transmitted, an identification flag Hfd indicating whether or not the compressed image data is suitable for use in random and independent reproduction, is transmitted subsequently to a synchronous signal Hsd positioned at the beginning of a header Hv. At a reproducing end for reproducing the compressed image data transmitted according to the image transmission method, when analyzing the header Hv added to the compressed image data Dv corresponding to one moving picture, it is decided whether or not the compressed image data Dv is suitable for use in the random reproduction in a short time, by analysis of the identification flag Hfd.

Abstract: A digitally encrypted audio signal may be transmitted with an analog television signal. Access to the analog television video signal may be controlled by using graphics overlay techniques. The use of digital encryption techniques on the audio channel prevents improper interception.

Abstract: According to the present invention, when an image data currently being received is switched over to the data from another image information device, the best picture quality is provided without stopping the image up to the next I frame even when the switching request is given at the middle of I frame.

Abstract: Methods and apparatus for spectrally-encoding plural source images and for providing the spectrally-encoded plural source images in a composite image, for rendering the composite image on a substrate, or for recovering at least one of the encoded source images from the rendered composite image such that the recovered source image is made distinguishable. At least one of the source images includes image content in the form of a textured image. When the rendered composite image is subjected to illumination by one of the narrow band illuminants for which a source image was encoded, the textured image in the recovered source image becomes visually detectable.

Abstract: A communication system including a transmitter, a receiver, and a serial link, in which encoded data (e.g., video, audio, and optionally also other auxiliary data) are transmitted from the transmitter to the receiver. The serial link can but need not be a TMDS or TMDS-like link. In typical embodiments, packets of encoded audio data are transmitted over each of one or more channels of the link during data islands between bursts of encoded video data, a pixel clock is transmitted over the link, and the receiver regenerates a clock for the audio data using time code data in the packets and the pixel clock. Other aspects of the invention are transmitters for transmitting encoded data and a pixel clock over a serial link, receivers for receiving such data and pixel clock and performing audio clock regeneration, and methods for transmitting encoded data and a pixel clock over a serial link and performing clock regeneration using the transmitted data and pixel clock.

Abstract: In a video TS packet separator, a video TS packet VTSP is extracted from a TS (transport stream). In a PES packet analyzer through a TS packet generator, the video TS packet is decoded, re-encodes at a predetermined bit rate, TS-packetized and supplied to a switch input terminal. The switch input terminal is also supplied with non-video TS packets UVTSP from a TS packet buffer. A controller is provided to control the TS packet generator and switch based on timing information and PCR from a TS packet timing manager. Thus, codes in the TS can be converted.

Abstract: An information processing apparatus capable of receiving and processing a variety of types of input is shown with features that make it easy to add properly synchronized information as desired. A CCD photoelectrically converts into image signals the light of objects collected by a photographic lens. The image signals of the photographic images are digitized by an analog/digital (A/D) conversion circuit, and are compressed by a digital signal processor (DSP). A central processing unit (CPU) records on a memory card the photographic images along with their input date and time as header information. When sound information is received through a microphone during reproduction of the photographic images, the CPU 34 records on the memory card the sound information along with the input date and time header information of the photographic images.

Abstract: A multi-camera capture system includes an audio synchronization marker to provide synchronization marks with the video streams captured by the multi-camera capture system. In one embodiment of the present invention, the audio synchronization marker generate a plurality of substantially similar synchronizing audio signals. Each camera of the multi-camera capture system records a synchronizing audio signal with the video stream captured by the camera. The synchronizing audio signals contain synchronization marks which are used to synchronize the video streams of the cameras.

Abstract: In an audio/video/computer graphics data synchronous reproducing/synthesizing system, a demultiplexer separates a bit stream in which an audio signal, a video signal, and computer graphics data are compressed and multiplexed, into compressed audio and video signal streams, audio and video signal time reference values, and a compressed computer graphics data stream. An audio PLL generates a first decoding clock. An audio decoder decodes the audio signal. An audio memory stores the decoded audio signal. A modulator modulates the audio signal in accordance with sound source control information. A video PLL generates a second decoding clock. A video decoder decodes the video signal. A video memory stores the decoded video signal. A CG decoder decodes the computer graphics data and event time management information. A CG memory stores the decoded computer graphics data. An event generator generates an event driving instruction. A detector detects viewpoint movement of an observer.