MXPA01000580A - Method of converting a packetized stream of information signals into a stream of information signals with time stamps and vice versa - Google Patents

Abstract

The invention relates to a method of and converting means for converting a packetized stream of information signals representing information arranged in separate, consecutive data packets of digital format, into a stream of information signals with time stamps. After establishing time stamps related to a time of arrival of a data packet, the time stamps of several data packets are grouped into a time stamp packet wherein, in an embodiment, the size of the time stamp packet is equal to the size of a data unit.

Description

Method to convert a packaged flow of information signals into a flow of information signals with timestamps and vice versa.

The invention relates to a method for converting a packed stream of information signals representing information accommodated into separate and consecutive data packets of the digital format into a flow of information signals with timestamps, the method receives the serial stream of the information signals and detects the data packets in the serial flow of the information signals, while it establishes a time of arrival of the data packet and generates a time stamp of the data with relatón at the time of arrival of each packet of detected data.

The invention also relates to a method for converting said information signal flow with timestamps into a packaged stream. The invention relates further to a conversion means for carrying out both methods, as well as to a system for storing and withdrawing or transmitting said information signal flow.

The object of the invention, as described in the introductory paragraph, is known from the international patent application WO 96/30905, document (Dl) included in the list of references. More specifically, the document (D1) shows the recording and reproduction of an information signal containing packets that may arrive in an irregular manner as a function of the time in the serial data stream of an MPEG information signal. Said MPEG information signal is used for the serial transmission of a digital data stream representing a compressed video digital video signal and a corresponding compressed audio signal. For example, the outline of the Grand Alliance HDTV System Specification dated February 22, 1994, document (D2) in the list of references, more specifically Chapters V and VI of this specification, includes a description of a transport system for transmitting an MPEG information signal for broadcast or broadcast purposes via a cable network.

The Moving Pictures Experts Group (MPEG) has developed the format of an MPEG information signal. This group was established in order to develop standards for codified representation and compression of films, audio and their combination. This group operates with the system of the Joint Technical Committee of ISO / IEC. The standards that are currently produced are MPEG-1 (ISO 11172), MPEG-2 (ISO 13818) and MPEG-4. Industries and different international organizations have adopted these standards. The standards allow internal operation in digital audio and video applications and services. Within an MPEG serial data stream, video and / or audio signals can be transmitted by means of flow packets having a fixed number of bytes (188), the first byte being a synchronization byte. A flow transport packet includes information from only one of the video signals, one of the audio signals or one of the data signals transmitted via the MPEG serial data stream. The synchronization of the decoding and presentation in a receiver is important for a system of digital data delivery in real time. This is in order to ensure that a video signal is presented at an adequate speed, that the audio and video remain synchronized and that the decoder can properly handle its amplifiers (buffers). A loss of synchronization leads to an excessively high or low flow in the decoder and, as a consequence, the loss of information. This is different from analogous information, such as in NTSC where the information for movies is transmitted in a synchronized manner so that one can derive a clock directly from the synchronization of the movie. However, in a digital compression system the amount of data generated for each film is variable, according to how much depends on the complexity and approach encoder of the film. In this way, the time can not be derived directly from the start of the movie data. There is no natural concept of synchronization pulses in a digital bit stream. Therefore, the base of the time on the decoder side must be ensured with that of the encoder. The solution is to transmit the time information with the selected flow transport packets in order to serve as a reference for the comparison of the time in the decoder. This is done by transmitting, in regular periods, the sample of a reference clock that is called the clock program reference (PCR). This clock reference (PCR) indicates the expected time of completion of the reading of said time stamp that comes from the .bits flow in the decoder. It compares the phase of a local clock that walks in the decoder with the value of the PCR when it is obtained, in order to adjust the clock speed, in case it is necessary, to determine if the process is synchronized of decoding. Therefore, an MPEG transport stream can be considered as a real-time transport stream. With the use of a second type of time stamp, called the decoding time mark (DTS) or the time stamp of the representation (PTS), the exact moment is indicated, relative to the clock that assures the decoder before mentioned, where a video panel or an audio panel has to be decoded or presented, respectively. The flow transport packages will be transported through a medium. If the delay of this medium is not equal for each flow transport packet, then it is possible to corrupt: "the basis of the time to decode." An extra delay of the transmission between two flow transport packets that follow each other and that contain a PCR will cause a vibratory movement in the clock of a decoder, therefore, the respective standards allow only a specific amount of vibratory movements.

A storage or recording device can also be treated as a transmission channel with infinite delay. In reproduction, the time between successive flow transpoite packets must be reconstructed in such a way to be equal to the time between the flow transport packets that follow one another when they arrive at the recording device input during the recording. Furthermore, it can be said that recording or storing a complete signal of MPEG information, comprising multiple program streams, is generally not possible due to the amount of al1? Of data of the MPEG information signal. Therefore, only one or a few of the video signals and their corresponding audio signals corresponding to a selected program stream will be selected in practice to record. However, as a consequence, the flow transport packets corresponding to a specific program flow will, in general, be selected in an irregular manner as a function of the time. In order to preserve the time relationship between the subsequent selected flow transport packets, the previously mentioned document (D1) describes the measure to insert the timestamps in each recorded flow transport packet. After selection and storage, the time relationship between the subsequent packages with the reproduction can be recovered with the use of timestamps. According to the document (D1), the combination of time stamps and flow transport packets is incorporated into a specific data format (D-VHS MPEG2 ST.D) where the data is recorded with a system magnetic reproduction / recording as a digital video cassette player based on VHS. This format is not a standard MPEG format that represents a real-time data flow, but allows the representation of a data flow in a non-real time. According to the D-VHS MPEG 2 STD format, the recording of blocks of signals that represent a fixed amount of 112 bytes is allowed. Within two signal blocks of 112 bytes each, a 188-byte stream transport packet can be stored together with an additional time stamp corresponding to 4 bytes. (The other 32 bytes are used for purposes, such as synchronization, identification, and parity information). This format is only used within a digital VHS player. In applications such as those found in domestic digital networks, different audio / video and data devices can interconnect with each other. In a domestic digital network, digital services can deliver digital content, such as digital video broadcasting (DVB), to domestic digital networks with the use of cables, satellites, ether or telephone, or where digital content sources can be used. find inside the home, such as digital video cameras, cameras and digital media previously recorded as CD and DVD. A home digital network can allow that content to be transported from a D-VHS player or between two and between personal computers, television sets, video printers, scanners, etc. An IEEE 11394 network can connect all these devices together. IEEE-1394, as shown in "Bar in High Performance Series P1394", sketch 7.1, version 1 issued on August 15, 1994 from the IEEE standards department and document (D3) in the reference list, defines to a digital interface for simultaneously transporting multiple high speed audio and video streams in real time between said digital devices. The bar that uses this interface is called "the IEEE 1394 bar", but it is also known as "Firewire" (Appie's Trademark) or "l-Link" (Sony's trademark). The standard has been adopted by PC, Consumer Electronic, DVB (Digital Video Broadcast - Digital Video Broadcasting) Industries. IEEE-1394 defines a transport mechanism for packages, but not to the way in which these types of packages should be used for specific data in real time, such as MPEG-2. However, IEC-61883 defines the way in which specific AV formats can be transported with a 1394 bar. IEC-61883 contains, for this purpose, among other protocols, a common isochronous protocol (CIP) which is a generic method to pack data for its real-time application within the time slots of the bar (isochronous transfer) in the loading field of 1394 bundles of the bar. However, IEEE-1394 according to the MPEG Flow Transport Protocol adapts IEC 61883-4 to transport standard MPEG2 flow transport packets of 188 bytes only. There is no space within this standard IEEE-1394 protocol to carry non-standard MPEG packets of, for example, 192 bytes, such as those obtained by adding a 4-byte time stamp to each flow transport packet in a flow of non-real time transport, as explained above. One purpose of the invention is therefore to overcome the aforementioned disadvantage and, more generally, to overcome the problem of adding time stamp data to data packets with a fixed size. The method according to the invention is characterized by grouping a plurality of the data of the time stamp of several data packets into a packet of the hour mark, thus generating a signal of the brand's package of the time represented by the brand packet and transmits the serial flow of the received information signals together with the generated timestamp packet signals so that a unique association can be established between the brand data of the time and a corresponding data packet. The invention is based on the following recognition. When collecting the data of the time stamps of different packages in a special package of timestamps, instead of adding each data packet of the time stamp to the corresponding data packet, you can keep the agreement format. to which these data packets are formatted, such as MPEG. This has the advantage of avoiding the use of a conventional format, such as the D-VHS MPEG2 STD format, in addition, a transfer to a size and / or data storage of an MPEG information stream is obtained. that the original order and the time relation of the packets can be stored again a second later when using the aggregated information of the time stamp, and compatibility with the devices and transmission channels is maintained, such as the IEEE- 1394 based on the standard MPEG format In a method where the data packet comprises a fixed number of digital data N units and the hour mark data comprises M digital data units with M <; N, a further advantageous method according to the invention is characterized in that the hour mark data packet comprises digital data N units. By maintaining the size of N data units, a packet of the time stamp can also be considered as a standard package in a standardized packet flow. The time stamp package will be accommodated in the reserved space according to a transmission format or in a receiving device adapted to process packages of fixed quantities of digital words. For example, no special measures should be taken with the transmission channels based on IEEE-1324. Also, what? Devices not adapted to modify packet flow can handle a packet of timestamps as one of the other packets and will not need modification. An observation is made that not all data units in a timestamp packet need to be used for timestamps, since data units can also serve as full data units or as synchronization units . (>: Another advantageous method according to the invention is characterized by providing the packet of the time stamp with identification information. This has the advantage that a receiving device can discriminate one packet of time stamps from another and not standard packets that may be present in a received packet stream. A more detailed first method according to the invention is characterized by providing data of the time stamp in the time stamp package with related information indicating the corresponding data packet. This has the advantage that, when reproducing the flow in real time, when data is missing or incorrect, a link can still be established between a specific time stamp and a data packet. In addition, the sequence of data packets can be changed. A second, more detailed alternative method according to the invention is characterized by providing data of the time stamp in the time stamp package in an order that is in accordance with a transmission order of the corresponding data packets. In this way, you can associate the separate marks of the time in a packet of timestamp with the data packet n of a group of data packets that follow the packet '. j of the hour mark. This has the advantage that no additional information has to be added. Another vendor method according to the invention is obtained by grouping only those data of the hour mark into a bundle of timestamps corresponding to data packets constituting together with the data package of timestamps a block logic of combined data packets, as they are used to encode or decode. This requires less modifications of the organization of a transport flow, while the existing management and processing of the data flow in logical blocks follows. Something advantageous in this aspect is a method according to the invention can be characterized in that the logical block of combined data packets corresponds to a block such as that used to encode errors or correct errors. If a sequence of data packets represents an encoded video movie, another advantageous method is characterized in that the first data packet of a movie corresponds to the first data packet of a logical block of films, as for example in the case of an encoded sequence of I-, P- and B- movies with video MPEG encoding. To process it subsequently, it is advantageous to match the start of an I- P- or B- movie with the start of a packet of timestamps. Another advantageous method is obtained in the case that a data packet sequence represents encoded video films and characterized in that the logical packet of data packets is selected according to a group of video movies. As for example a Movie Group, denoted as GOP in MPEG video coding.

A following advantageous method according to the invention is characterized by using a signal of a packet of timestamps for the synchronization time of a receiving device. When you recognize a signal from a timestamp packet as a synchronization packet, you do not have to add additional synchronization signals. In a preferred method according to an invention, a synchronization signal is transmitted before the transmission of a logical block of data packets. This allowed. ':; the easy recognition of the start of a logical block. When you format data packets according to flow transport package MPEG of N = 188 bytes, according to the invention, an advantageous method is obtained by grouping data of timestamps into a packet of timestamp of N = 188 bytes. It is noted that not all bytes in a packet need to be used for data or timestamps, since a packet of flow transport or a packet of timestamps can include a collecting part and a loading part.

These and other aspects of the invention will be apparent and clear with reference to the representations described hereinafter, as illustrated by the accompanying drawings and in which, Figure 1 shows a typical group in a home network with several digital audio / video devices connected together by an IEEE-1394 network; Figure 2 illustrates means for encoding and decoding audio and video information according to the MPEG-2 format; Figure 3 shows an MPEG-2 program stream and an MPEG-2 transport stream; Figure 4 shows part of the format of a transport flow packet of a transport flow; Figure 5 shows the format of a program collector of a program flow; Figure 6 illustrates the aggregation of additional timestamps to transport flow transport packets; Figure 7 schematically represents a device for recording an MPEG-2 transport stream; Figure 8 shows the format for storing the flow transport packets according to the D-VHS MPEG-2 STD format; Figure 9 schematically represents a device for reproducing a transport MPEG-2 stream; Figure 10 shows the format of a bar package; Figure 1 1 illustrates a transport of an MPEG flow transport packet on an IEEE-1394 bar I using bar packages of Figure 10; Figure 12 shows a method for adding timestamps to flows in real time according to the invention; Figure 13 shows schematically the conversion of means according to the invention to carry out the method illustrated in Figure 12; Figure 14 shows a method for separating time stamps from a non-real time flow according to the invention; Figure 15 schematically shows conversion means according to the invention for carrying out the method of Figure 14; Figure 16 shows various methods according to the invention for grouping hour marks into time stamp packages; Figure 17 uses the result of the time stamp separation of a non-real time flow according to the method illustrated in Figure 15; Figure 18 shows a system according to the invention for storing and withdrawing a real-time flow of information signals.

The transmission of digital information signals can be found ascending in domestic digital networks where digital services deliver digital content to households via digital networks that use cables, satellites, ether or telephones, or where other sources of digital content can find themselves inside the home, such as video cameras, cameras, digital media previously recorded, such as CDs or DVDs. A digi network: - ':! Domestic allows this content to be transported to devices such as D-VHS players, computers, video cameras, video printers, scanners, etc. Figure 1 shows a typical group, where an IEEE-1394 1 network connects several digital devices together. The group comprises a satellite receiver 2 for receiving digital video broadcast signals. The satellite receiver 2 is connected to an installation box 3 which is adapted to receive digital signals from a satellite (DVB) and pass them to a television set 4 or to a magnetic reproduction / recording system, such as a VCR 7 player for its storage. More digital information signals can be transmitted to the installation box 3 by cable or telephone via an input terminal 5 or by means of a digital video camera 6. It can also be transmitted a personal computer 8, a printer 9, an ap telephone slot 10, an optical drive 11 using for example a Digital Versatile Disk (DVD) or a Compact Disc (CD) and a storage mass unit 12. This mass storage unit 12 comprises a large storage memory as a storage unit. Magnetic cassette 14. Alternatively, an optical drive can be used. MPEG-2 provides a two-layer multiplex approach. The first layer is designed to ensure a close synchronization between audio and video. This layer is called elemental flow packed PES. The second layer depends on the intended means of communication. The specification for environments without errors, as in a crazy storage! it is called PS MPEG-2 program flow, whereas the specification that attacks error-prone environments is called TS MPEG-2 transport stream. Figure 2 illustrates this approach to encoding audio and video data respectively with a video encoder Je 15 with respect to an audio encoder 16. With a first subsequent packer 17, a V-PES empacuate elementary stream is obtained, whereas with a second subsequent packer 18 is obtained an elementary stream of audio packaged A-PES. Both bit streams are input to a multiplex for program flow 19 to generate a PS program stream and a transport transport multiplex 20 to generate a transport stream TS. Within a PS program flow, elementary stream program packets (PES packets) of different bit elementary streams are multiplied by transmitting the bits for full PES packets in sequence resulting in transport packets of different sizes. Figure 3 illustrates said transport packets of different sizes in the form of a PES packet 31 comprising an elementary stream program header 33 and an elementary stream program load packet 34. In contrast, in the transport stream the PES packages are transmitted just like the pf-cargo transport or fixed-size transport. Figure 3B illustrates fixed size transport packets 32, each of which comprises a transport packet header 35 that includes information for the identification of the bit stream and the transport load packet 26. An observation is made in which A transport stream can take several programs where audio and video data is multiplied together. The transport stream encodes by means of a channel by means of a channel encoder 22 in order to obtain transmission signals adapted for transmission via a transmission channel. It is noted that generally a transmission channel can not only comprise a cable or a broadcast channel, but also storage means such as magnetic and optical means. In a receiving site, the data corresponding to a program is separated by a demultiplier d. flow transport 21 from the received flow multiplied with the use of specific information contained in an association table of an unspecified program and table of program maps. A channel decoder 23 subsequently regenerates the transport stream TS which is demultipulsed by a transport stream demultiplier 21 in a packaged elementary stream of V-PES video and in a packed elementary stream of audio A-PES. These flows are removed from the packet by de-packers 26 and 27 in different packets once again and finally decoded by audio and video decoders 28 and 29 for real-time presentation in a display device 30. These elementary streams can be slightly synchronized ( as it is generally necessary for digital TV programs or for digital radio programs) or not synchronized (in case of programs that offer download software). For this purpose, an MPEG information signal contains clock reference data (such as SCR in the case of MPEG-1 or PCR in the case of MPEG-2) in order to synchronize in the receiver device a local clock 24 which generates TC2 time control signals with a local clock 25 in the transmission device that generates time control signals TC1. These clock reference data are sent periodically, for example, every lOOms. The average distance in time between packets occurring in an MPEG transmitted between those two clock reference signals should be set to a high degree. Thus, an MPEG stream is a flow in real time. For a detailed explanation of the contents of the fixed-size transport packet 32 in FIG. B, reference is made to document (D2) in the reference list, more specifically in chapter V, while FIG. shows schematically the main characteristics. Hereinafter, it will refer to a fixed size transport packet 32 as a simple transport packet 32. In Figure 4, the transport packet 32 is illustrated with a fixed size of 188 bytes. The transport packet 32 contains a transport packet header (reference 32 in Figure 3B) which contains a 4-byte link header 37 and an optional adaptive header 41 of variable size. The remaining bytes are saved for the load transport packet 39. The choice of this packet size is motivated by several reasons, such as the probability of error correction of the packet, the compatibility with the block sizes of the blocks typical, error correction approaches and internal operation with the ATM format. The first byte in the link header 37 is a synchronization byte 38 which can be used for * the synchronization of the packet. Synchronization byte 38 is identical for all transport packets. The other three bytes in the link header 37 comprise identification information, such as a packet identifier 40. This provides a mechanism for multiplying and demultiplying bit streams by allowing the identification of packets belonging to a particular elementary stream or a flow of bits. bit control. An identification header flag 42 marks the presence of an optional adaptation header 41 in the link header 37. The adaptation header 41 may comprise a PCR field 43 representing time information for closing a time base at the receiving site with that in a transmission site. A PCR flag 44 marks the presence of said PCR field 43. This time information is regularly transmitted at least once every 100 milliseconds in the form of a sample of a MHz clock 27 as a reference mark of the time, the which indicates the expected time of completion of the reading of the PCR 43 field of the bit stream in the receiver. The phase of the local clock that runs in the receiver is compared to the value contained in the PCR 43 field at the time it is obtained to determine if a decoding process is synchronized. In general, the value contained in the PCR 43 field (PCR value) of the bitstream does not directly change the phase of the local clock, but only serves as an input to adjust the clock speed of the decoder (27 MHz nominal). The cycle time of the PCR value is approximately 26 hours. The PCR 43 field format contains 33 bits and another 9-bit extension field. This extension field has a cycle of or 299 to 27 MHz, where the field value of 33 bits is increased by one. (This results in this field being compatible with the 33-bit champion used for the 90 MHz clock in MPEG-1). The transport flow will be transported by means. If the delay of this medium is not the same for each transport flow packet, then it is possible to corrupt the time base for decoding. An extra delay in transmission between two succeeding flow transport packets containing a PCR 43 field will cause a vibrational movement in the 27 MHz clock of the decoder. Therefore, ISO / IEC 13838 allows only a specific amount of vibratory movements. The exact moment is indicated, relative to the time reference described above contained by the PCR field 43, where an audio or video mark has to be decoded or presented in a respective manner, by a second type of timestamp. These brands are called decoding brands of the hour (DTS) or time presentation marks (PTS). These fields are contained in the PES headers 33 (Figure 3B) of the fixed size transport packets 32 in a transport stream. The new PES packet data always starts a new transport packet and the PES packets ending in the middle of a transport packet are followed by closing bytes for the remaining size of the transport packet. The format of a PES? 1 packet is illustrated in Figure 5. The PES packet of Figure 3 A includes a PES 33 header and a load packet.

PES 34. The PES header 33 includes a packet start code prefix of 45, a flow identifier 46, and field for the PES packet size 47, flags of the PES 48 header, a field for the size of the PES header 49 and a field for the PES 50 header. The flags of the PES 48 header mark the presence of specific fields of the PES 50 header. A two-bit flag 51 indicates whether a mark of the time presentation (PTS) or a decoding mark of the time (DTS) is present in the PES header 33 in the form of a DTS / PTS field 52. The PTS / DTS field 52 comprises 33 bits. Note that the clock of the channel 22 encoder or the decoder of the channel 23 shown in Fig. 2 is set completely separate from the clock that is in the video encoder 15, the audio encoder 16, the video decoder 28 and the audio decoder 29. In addition, the transmission of said MPEG information signal in the form of recording and playback from a recording loader, such as a magnetic recording loader or a storage device, with a drive of Hard drive requires that special measures be taken in order to keep the information in real time. In this regard, reference is made to the European patent application EP-A 0 858 230 registered above, document (D4) of the reference list. In the reproduction, the time between successive transport flow packets must be reconstructed in such a way that it is equal to the time between flow transport packets that follow each other, as they arrive at the input of the recording device during the recording. In addition, as explained above, the MPEG transport stream can include more than one video program. Because the bit rate of the MPEG transport stream is usually greater than the bit rate of the recordable signal, only one video program of the MPEG serial transport stream can be selected for recording. The selection of a video program means the selection of transport packets of the MPEG transport stream comprising the information related to said video program and the elimination of other transport packages. Figure 6 A shows a serial MPEG transport stream as a function of time t comprising transport packets 32 (P1, P2, ...). As shown in Figure 3, each transport packet 32 comprises a transport packet header 35. Selecting only those transport packets 32 that include information »related to the selection of a video program results in the selection of , for example, the selected transport packets P1, P3, P5, ... as shown in Figure 6B. Immediate transport packages P2, P4, P6 ... will be discarded. As a result, a data stream has been obtained in the recording array for recording in the recording loader, as shown in FIG. 6b, which shows the data stream as a time function. At times of time t1, t3, t5, t8, t9 ... which represent the time of reception of each of the corresponding selected transport packets P1, P3, P5, P8, P9 ..., marks of the hcra (TS1, TS3, TS5, TS8 ...) additional (with respect to the DTS and PTS values mentioned above). Those additional timestamps can contain a count value, including for example 4 bytes, of a counter that is capable of counting subsequent counting cycles from a start value. The additional timestamps generated with aggregate to the corresponding transport packets 32, as shown in Figure 6C with reference 53. A keying introduced to obtain a bit rate is also illustrated in Figure 6C. minor required to record or store. Alternatively, Figure 6D shows groups of transport packets composed 32 and additional hour markers 53, as required when writing / reading in groups for / from a storage medium, such as a hard disk drive. Figure 7 schematically illustrates a recording apparatus for recording an MPEG-2 stream in real time, as is known from the document (D4) in the reference list. The input terminal 54 is connected to a closed phase circuit 55 which encloses words such as the PCR clock information included in the MPEG transport packets in the synchronization. The closed phase circuit 55 generates a clock signal with an oscillation frequency of the same frequency of the incoming MPEG signal which is almost 27 MHz. This clock signal is provided to a chronometer 57. This stopwatch 57 counts up ( or descending) with this frequency and generates cycles of CV count values initiated by a reset pulse R. The count value CV of the timer 57 at the time of arrival of a transport packet TP is available at the output of a circuit joint 58. For this purpose, transport packets TS are also input to an arrival detector of packet 59 to determine the arrival time t of a transport packet Pi. In addition, the transport packets TP are introduced into a selection unit 60 to select a specified user program with corresponding selected transport packets. The selection unit 60 is linked to a combination unit 61 to combine the selected transport packets with the corresponding additional timestamps TS generated from the seal circuit 58. A synchronization circuit 62 is present to provide more time. This synchronization circuit 62 receives clock pulses from the closed phase circuit 55 and provides reset pulse to the timer 57. Moreover, the synchronization circuit 62 provides pulse for the control of the T-CTL time to the recording unit 63. and the digital signal processing unit 64. These pulses for the T-CTL time control indicate, for example, a start section for the cassette of the recording unit 63. The digital signal processing unit 64 leads to The coding of the channel required for recording in the recording format with the recording unit 63 is performed. At least one of the smoothing buffer 65 is present between the combination unit 61 and the digital signal processing unit 64. The packages Transport compounds must be written in a cassette format, and as shown in the document (D4) in the list of references. The data is written to the cassette in units of synchronization blocks with a fixed size of 112 bytes. Two consecutive synchronization blocks are used to store a transport packet with its additional hour mark. Figure 8 illustrates this format. The first synchronization block 66 contains the first part 68 of the transport flow packet and the additional time stamp as a packet header 69. The second synchronization block 67 contains the second part 70 of the transport flow packet. The synchronization blocks 66 and 67 further contain synchronization words 71, identification information 72, a main header 73m auxiliary data 74 and parity information 75 according to the D-FHS MPEG-2 format. Figure 9 schematically illustrates a device for reproducing an MPEG-2 transport stream also known from the document (D4) in the reference list. The reproducing device shows much similarity with the recording device of Figure 7. The recorded signal comprising the packets composed of timestamps of the channel coding according to the format of Figure 8 is read from a charger. recording by means of a reproduction unit 76. This signal is supplied to a digital signal processing circuit 77 for decoding channels in order to obtain the composite packages. The composite packages are introduced to an amplification unit (buffer) 78 to amplify and desalyze. Se >; remove the time stamps from the compound packages by removing circuit 79 to obtain the original transport packages. The original transport packages are supplied to the output terminal 80 depending on the time stamps. An oscillator circuit 81 is present and supplies clock pulses based on an oscillatory frequency, such as, for example, 29 MHz to a timer 82 and to a synchronization module. This oscillating frequency must be substantially equal to the oscillation frequency of the engraving device. The timer 82 counts upwardly (or downwardly) with this frequency and generates cycles of CV count values for a comparator 84. The comparator 84 receives the mark of the TS time removed from the packages bearing timestamps, from the amplification unit 78. At the time when the value of a timestamp TS with a CV count value coincides, the comparator 84 generates a coincident signal and passes it to the amplification unit 78. The transport packet that it comprises the mark of the time for which the match is established is supplied to the output terminal 80 in response to the match signal. The synchronization circuit 83, general information for the control of the time (T-CTL), as a signal of the start section), for the digital signal processing circuit 77, as well as for the reproduction device 76 and a signal of reset R for the timer 82. It is noted that the synchronization circuit redbeads additional time information from the playback device via the digital processing bus 77. Alternatively, to record and reproduce, a transport stream can be transmitted Real-time MPEG between digital devices via a bar that operates with a 1394 protocol, as defined in reference (D3) of the list of references. A single 1394 bar can connect up to 63 devices or "nodes" using only end-to-end connections. Each "node" has a unique address that it has assigned itself after establishing its position in the network. In order to make 1394 work as a bar: each device acts as a "repeater", where data is written or read directly into the corresponding memory space. There are two categories of data traffic allowed in the bar: asynchronous traffic and isosynchronous traffic. Asynchronous data traffic uses data packets with a 64-bit white address and is used mostly for read, write and close memory operations. An isochronous transfer mode is used for real-time data. Then, the 64-bit address is changed to a 6-bit virtual channel number. Any receiver can receive data from any channel. All nodes capable of an isochronic transfer must maintain a 32-bit clock. A node is selected to be the "cycle master". Every 125u, this node sends a special packet containing the value of its own clock, which is used by all the other nodes to synchronize its own clock: "global time of the hour". This can be used to create constant end-to-end transport delays for real-time data, such as MPEG-2 transport packets. It is noted that IEEE-1394 defines only one transport packet mechanism, but nothing about how to use these types of packets for specific classes, such as MPEG-2. However, IE-61883 defines how specific audio / video formats can be transported with a 1394 bar. 1EC-61883 contains three main components for this purpose: a common isochronous protocol (CIP), a protocol for handling connections (CMP) ) and a protocol for the control of functions (FCP). CIP is a generic method to pack data for real-time applications in the 1394 isochronous packet load field. A header Special CIP is inserted at the beginning of each load to indicate how the data were packaged for the application of levels. The timestamps attached to the application packages allow delivery with a constant transport delay. The CMP provides a partner-to-partner mechanism to establish and maintain isochronous connections. The FCP provides a framework through which high-level commands can be communicated. Figure 10 shows a format for transporting transport packets over a bar 1394. Transport packets 85 and 86 comprise 188 bytes each. It is preserved in timestamps contained in the headings of the source of the 87 and 88 packets, each of 4 bytes, the arrival time of these transport packets 85 and 86 in a source device before transmitting them by means of the bar. A combination of a transport packet 85 respectively and 86 and a source header of the packet 87 respectively 88 is called the SP source packet of 192 bytes. The source SP packets are preceded by the CIP header 89. The combination of the CIP packet with a predecessor header of the packet bar 90 and a terminating word CRC 91 is called a bar packet or an isochronous BP packet.

According to this protocol, when a source device has to transmit transport packets in real time, it requests a time slot in the bar. According to the protocol of the bar, a particular slot of time is located in the source device, from a set of periodically repetitive time slots. However, if a source device passes an MPEG signal, but does not create it, you will need to amplify an incoming transport packet to the beginning of the time slot in which it can be transmitted. This means that the included synchronization information, such as the SCR values in the case of MPEG-1 or PCR values in the case of MPEG-2, will no longer correspond to the time of transmission of these signals. This would mean that these values can not be used to synchronize a decoder of a receiving device. This can be corrected by including an additional clock in the source device, which is synchronized with the incoming MPEG transport packets. A sample of this additional clock is drawn at a time corresponding to the instant in which the SCR or PCR signal is transmitted in the time slot that is located for transmission according to the protocol of the bar. The value of the sample is used to change the SCR or PCR value in the MPEG transport packets. For a more detailed description, reference is made to the International patent application WO 96/01540, document (D5) of the reference list, with regard to the transmission of packets and a signal bar. However, it can be considered disadvantageous that for this correction, the source device has to interpret the MPE transport packets in order to locate the SCR or PCR values. The document (D5) also shows a system which avoids this and which is shown schematically in Figure 11. An origin device 92, adapted to receive MPEG transport TP packets at an input terminal 93, is connected by means of a bar 94 with a destination device 95. The source device 92 and the target device 95 includes clocks 96 and 97 respectively. The clocks 96 and 97 are synchronized with each other, for example in response to signals that are periodically created in the bar 94 by a master time apparatus that can be connected to the bar 94. The originating device includes a unit for marking the time 98 that adds time stamps generated by clock 96 to transport TP packets received at the time of receiving them. The timestamps are inserted in the header of the source package 88 (Figure 10). The resulting source SP packets are supplied to a CIP 99 unit that inserts CIP headers into the SP source packets in order to obtain CIP packets. A bar pack generator 100 generates a bar packet header 90 and a CRC word 91 in order to obtain a bar packet BP. The BP bus packages are temporarily stored in the transmit amplifier 101 until they can be transmitted. Subsequently, in the time slot located according to the protocol of the bar, the packet of bars BP is transmitted in combination with the sample value of the clock 96. This packet of bar BP is received by the target device 95. and stored, by means of a CRC review unit 102, in a compensating amplifier 103 until the clock 97 of the target device 95 exceeds the time stamp of the clock 96 transmitted with the transport packet included by means of a value of previously determined delay. In this way, the time of the signal produced by the source device 92 is reproduced with the delay value, which is chosen at least as the maximum delay that can be caused when waiting for the time slot located in the device. of origin 92 according to the protocol used for bar 94. Thus, the start of each transport packet TP will remain in the output state at the output terminal 104 with a suitable time. In case ofIn addition to the time stamps present in the headers of the source packets, more time stamps have been added to the 188-byte MPEG transport packets, the recording and playback devices shown in Figures 7 and 9, The resulting length of 192 bytes will not fit into the conventional format according to IEC-61883 to transmit transport packets on a 1394 bar. Therefore, Figure 12 shows a method according to the invention for adding those other timestamps to a flow in real time. First the detection takes place (step 105) and the establishment of an arrival time (TO-A) (step 106) of transport packages. Then the selection of transport packets belonging to a selected program flow takes place. Subsequently, a corresponding hor mark is generated (step 108) which represents the arrival time. Then it is checked if the number N of timestamps exceeds a specific amount (step 109). This amount can be variable depending on the size of logical blocks of data packets that must be processed or that are at the beginning of said blocks. A packet of timestamps does not need to be completely filled with timestamps, but filling bytes can be completed. If this is not the case, the generated timestamp is added to a timestamp packet that contains several timestamps of other transport packets (step 110) and the next transport packet is selected one more time (step 105). ). The specific format of said timestamp packets is explained in more detail with the reference to Figure 16. Otherwise, the number N is reset to zero and a signal from the timestamp packet (step 111) is generated. represents the hor tags generated and collected up to step 110. Optionally, (step 112) ID identification information may be added to the signal of the time stamp packet for identification purposes. The signal generated from the combined time stamp packet (step 113) with the corresponding transport packets previously selected (step 105) in a serial packet flow of transport packets timestamp packets. Finally, it is determined (step 114) whether all transport packets of the selected program flow have been handled. In case of handling a transport packet that does not complete the program flow, the next transport packet is selected (step 105). Figure 13 schematically shows conversion means according to the invention for carrying out the method illustrated in Figure 12. An input terminal 115 is coupled with a closed-phase circuit 116, which will ender in synchronization words as the PCR closing information included in the MPEG transport packets. The closed phase circuit 116 generally generates a clock signal with an oscillation frequency of the same frequency of the incoming MPEG signal which is almost 27 MHz. The clock signal is supplied to a chronometer 118. This chronometer 118 counts upwards ( or descending) with this frequency and generates cycles of CV count values initiated by a reset pulse R. The count value CV of the timer 118 at the arrival time of a transport package is available at the output of a joint circuit 119. For this purpose, transport packets are also introduced into a packet arrival detector 120 to determine the arrival time of a transport packet. A sequence of CV count generated values representing the arrival time of the transport packets in an amplification means 121 is stored for temporary storage. A time stamp packet generator circuit 122 constitutes a combined packet of time stamps temporarily stored in the amplifier means 121 according to the method described in Figure 12. This may also involve adding association information to the time stamps. for its association with the corresponding transport packages or to identify information for the identification of the time stamp package. A synchronization circuit 123 is present to provide more time. This synchronization circuit 108 receives the clock signal of the closed phase circuit 116 and provides reset pulses to the timer 118. In addition, the synchronization circuit 123 supplies time control to the generator of the timestamp packet 122.

The transport packets are entered into a selection unit 124 for the selection of a specific user program with corresponding transport packets selected. The selection unit 124 is coupled with a combination unit 12 to combine the selected transport packets with the corresponding time stamp packets generated by the timestamp packet generator 122. combined flow of transport packets and brand packets of time transmission means 126 is provided to transmit the packets. The transport means 126 is adapted to the transmission channel involved. As an example, the transmission means may incorporate transmission bar means to form d-bus packages, as described in Figure 10, for transmission via an IEE 1394 bus. Transmission signals are available in a bus terminal. output 112. D optionally, synchronization circuit 123 may provide transmitting means 126 with time information to also use packets of time stamps for synchronization purposes. Figure 14 shows a method for separating time stamps from a flow that is not in real time according to the invention. First, packets of hormarks are detected within a serial stream of timestamp packets (step 128). Then, the separation of the time stamps is carried out in a detected packet of hor markings (step 129). The separate timestamps (step 130) are associated with the corresponding transport packets. The time stamp for each transport packet 131 is determined, while a synchronization signal is generated (step 132) using the time stamp generated and a clock reference. This synchronization signal is used to transmit (step 133) the transport packet corresponding to the moment e which is presented by the time stamp in order to once again obtain the real time flow of transport packets. Finally, it is determined (step 134) to proceed with the next time stamp in the selected time stamp packet (step 130) or with the detection of a subsequent time stamp packet (step 128). Figure 15 schematically shows conversion means according to the invention for carrying out the method illustrated in Figure 14. A serial stream of TP transport packets and corresponding timestamp TSP packets, such as those generated, are received. for example by the conversion means described in Figure 13, by means of a receiving means 135. The receiving means 135 can be adapted to receive IEEE-1394 PB bus packets, as described in Figure 10, with the packages mentioned above as cargo. Within this flow, the timestamp packets are detected by time stamp packet detecting means 136. The time stamps are separated in timestamp separator means 137 and are supplied to time stamp generating means 138 for generate the timestamp represented TS. This value is supplied to a comparator 139. An oscillatory circuit 140 is present and supplies clock pulses based on an oscillatory frequency, such as, for example, 27 MHz to a chronometer 141 and to a synchronization circuit 142. This oscillatory frequency must correspond 'at the oscillatory frequency of the conversion medium, such as, for example, the one described in Figure 13, which is used to convert the original real-time flow of transport packets to a flow in non-real time. The stopwatch 141 counts upwards (or downwards) with this frequency and generates cycles of CV count values for a comparator 139. At the moment when the coincidence of a TS value of a timestamp with a CV count value occurs , the comparator 139 generates a matching signal which is fed to an amplification unit 144. This amplification unit 144 stores the previously associated transport packet TP by the association means 143. For this purpose, the association means 143 receives the transport packets TP from the receiving means 135 and the association information of the generating means of the timestamp 138. The transport packet associated with the time stamp for which a match was established is supplied. to the output terminal 145 in response to the coincidence signal. The synchronization circuit may receive time stamp detecting means synchronization information 136. FIG. 16 shows various methods according to the invention for grouping timestamp into time stamp packets. Figure 16 A schematically represents a real-time flow of transport packets 32 (TP1, TP2 ...) received at times of time t1, t2 ... Figure 16B shows a first method for grouping N timestamps 53 qu represent the time instants t .tn of a group of N transport packets TP1 ... TPN in a timestamp pack 147. The timestamp pack 14 comprises a collecting part 148 that includes identification information. It was noted that the transport packets 32 are no longer located at predetermined time instants on the time axis t. The sequence is repeated for each next group of N transport packets 32 (which result in a second packet of timestamps 14 and in a corresponding group of N transport packets TPN + 1 ... TPN2N). In order to be able to associate a specific transport packet 32 with the corresponding hor mark 53, the order in which the time stamps 53 are stored in the timestamp packet 147 is equal to the order in which the packets are accommodated. corresponding transport 32. A second alternative method for grouping timestamps is illustrated in Figure 16C. Each time stamp 53 within the timestamp packet 147 is preceded by association-specific information 146 to associate a specific time stamp 53 with the corresponding transport packet 32. This has the advantage that it is free to choose the order in which transport packets 32 are accommodated. In addition, one can deal better with a missing transport packet or with errors at a receiving site.

Figure 16D shows a slig different representation for grouping time stamp packets according to the invention. Only a predetermined number of timestamps 53 are collected in a packet of time stamps 147. This number is determined by the number of transport packets 32 that can be processed simultaneously by means of specific methods of coding or decoding data. . As for example the correction of errors of a block. Due to the predetermined number of timestamps 53 that are allowed for storage in a timestamp packet 147, the remaining space 149 can be completed with fill bits. The collecting part 148 comprises information related to the number of timestamps stored in the TSP timestamp packet (N = 5). Figure 16E illustrates another method according to the invention for grouping timestamps. A timestamp packet 147, which may be in the format of one of the previous timestamp packets, is also used for synchronization at a receiving site. The different time stamp packets 147 are transmitted to, at least most of the time, regular time instants t, t + At, t + 2At, etc. In case of adding filling bytes to the timestamp pack, time instants can occur locally and irregularly. This can be used to synchronize, for example, a recording device such as a magnetic cassette. Note that the aforementioned time instants are not related to the time instants shown in Figure 16 A. Figure 16F shows a sequence of transport packets 32 representing video films according to MPEG-2 video coding. A first group I of transport packets 32 constitute a reference film I, a second group B a forecasting film B and a third group P a forecasting overtaking film P. The first transport packet in a film I-, B- or P- corresponds to the first time stamp 53 in a packet of timestamps 147. This implies that filling bytes 160 may be required for an incomplete packet of marks of time 147. Figure 16G shows a SOP sequence of transport packets 32 representing video movies accommodated in groups of known GOP movies from MPE2 video encoding. The timestamps within a timestamp pack 147 refer to transport packets 32 within a group of movies. Figure 17 illustrates the time stamps 53 according to the method and as shown in Figure 14. Figure 17 A shows a non-real time flow of time stamp packages 147 and transport packages 32 along with the axis of time t. Figure 17B shows the converted real-time flow of transport packets 32, as obtained by the method illustrated in Figure 14. The information stored in time stamps 53 of the time stamp packet 147 is used to determine the original time instants ti in which the transport packages were originally received 32.

Figure 18 shows a system according to the invention for storing and withdrawing real-time flow of information signals. In an input terminal 150, a real-time stream of, for example, TP transport packets is received in the case of an MPEG stream. TP transport packets corresponding to a specific program stream are selected by a selection means 151. The selected TP transport packets can be further directed to suitable decoding means 152 such as, for example, an MPEG decoder. The decoding means 152 is further adapted to generate an audio or video display signal for a playback device 153 such as, for example, a television set. Reference information of the clock present in the flow received in real time is entered as, for example, PCR values in the case of MPEG2 transport packets to a clock circuit 154. This clock circuit 154 supplies synchronization signals to decoding means 152, time stamp generating means 155 and means that remove hour marks. 156. The time stamp generation means 155 is described in more detail in Figure 13, while the means remove the time stamps 156 are described in more detail in Figure 15. However, the clock circuits in both representations they will be combined in the clock circuit 154. In addition, the transmission means in Figure 13 and the receiving means in Figure 15 are not necessarily adapted for an IEEE-1394 bus, but can be adapted to connect to a dirve. 157-track hard disk, for example, a SCSI interface. The non-real time flow of TP transport packets and the TSP time stamp packets generated with the time stamp generating means 155 are temporarily stored in the hard disk drive 157. The hard disk drive 157 is connected via of an IEEE-1394 bar with a magnetic cassette unit 158 via suitable encoding and decoding means 159. It is transferred to the transport packets TP and the TSP timestamp packet stored in the drive of the hard disk 157 in groups towards or from the digital unit of the magnetic cassette 158 with the use of the bar protocol with packages of BP bars. The format used between the encoding and decoding means 159 and the digital unit of the magnetic cassette 159 can be in accordance with the D-VHS STD format, as illustrated in Figure 10. Even though the invention has been described with reference to preferred representations thereof, it should be understood that said representations are not limitative examples. In this way, different modifications can be made apparent to those having experience in the art, without departing from the object of the invention, as defined in the claims. In addition, the invention prostrates on each and every novel feature or combination of features.

LIST OF DOCUMENTS REFERRED TO: (D1) WO 96/30905 (PHN 15.260) (D2) Grand Alliance HDTV System Specification, February 22, 1994; Chapters V and VI (D3) Bar in High Performance Series P1394, sketch 7.1, version 1 issued on August 5, 1994, IEEE standards department (D4) EP-A 0 858 230 A1 (PHN 14.818) (D5) WO 96/01540 (PHN 14.935)

Claims (41)

CHAPTER CLAIMEDICATORÍO Having described the invention, it is considered as a novelty and, therefore, the content is claimed in the following: CLAIMS:

1. A method for converting a packaged stream of information signals representing separately accommodated information, consecutive packets of digital format data into a flow of information signals with timestamps, the method comprising: receiving the serial stream of signals from information and the detection of data packets in the serial flow of information signals while a time of arrival of the data packet is established and time stamp data related to the arrival time of each detected packet of data are generated. data; the method is characterized by grouping a plurality of timestamp data of different data packets into a packet of timestamps; by generating a signal from the time stamp packet representing the time stamp data packet and by transmitting the serial flow of the information receiving signals together with the signals generated from the time stamp packet in such a way that a unique association can be established between the time stamp data and a corresponding data package.

2. A method according to claim 1, wherein the data packet comprises a fixed number N of digital data units and the time stamp comprises digital data units M with M < N and is characterized in that the packet of the hour marks comprises digital data units N.

3. A method according to claim 1 or 2 characterized by the provision of the package of timestamps with identification information.

4. A method according to one of claims 1, 2 or 3 characterized by providing the data of the time stamp in the time stamp package with association information indicating the corresponding data packet.

5. A method according to one of claims 1, 2 or 3 characterized by grouping the plurality of the data of the time stamp within a packet of timestamps in a certain order according to the order of transmission of the corresponding packages of data.

6. A method according to any of the preceding claims characterized by grouping only those data of the time stamps into a packet of timestamps corresponding to data packets that constitutes, with the packet of timestamps, a block logic of combined data packets, as used for coding and decoding purposes.

7. A method according to claim 6 characterized in that the logical block of data packets corresponds to a block, as it is used for error coding or error correction.

8. A method according to claim 6 wherein a sequence of data packets represents an encoded video movie and characterized in that the first data packet of a movie corresponds to a first data packet of a logical block of packets of data.

9. A method according to claim 6, wherein a sequence of data packets represents an encoded video movie and characterized in that the logical block of data packets are selected according to a group of video movies.

10. A method according to one of the preceding claims characterized by the transmission of the signal of a time stamp packet for the synchronization of a receiving device with a transmission device via a transmission channel.

11. A method according to claim 6 characterized by transmitting a synchronization signal that precedes the transmission of a logical block of data packets.

12. A method according to one of the preceding claims, wherein the data packets are formatted according to an MPEG transport flow packet N = 188 bytes characterized by grouping data of timestamps into a packet of timestamps N = 188 bytes.

13. A method for converting a stream of information signals representing separately accommodated information, consecutive packets of digital format data and timestamp packet signals generated according to any of claims 1 to 12 in a packed stream of information signals further characterized by receiving the serial flow of information signals and time stamp packet signals; detect the signals of the packages of the hour marks; separate the signals from the time stamps of the signals detected from the packets of the time stamps; associating a separate signal of timestamps with an information signal of a corresponding data packet; determine a time stamp based on the signal separated from the time stamp; generating a synchronization signal based on the time stamp to obtain a transmission time of the data packet; transmitting the information signal representing the synchronized data packet by the generated synchronization signal.

14. A method according to claim 13 characterized by detecting the signals of the packets of the time stamps based on the identification of the information that accompanies the signals of the packet of the time stamps.

15. A method according to one of claims 13 or 14 characterized by associating a separated sénal of the time with an information signal of a corresponding data packet based on the association of the information that accompanies the corresponding data packet.

16. A method according to one of claims 13 or 14 characterized by a signal separated from the time with an information signal of a corresponding data packet based on the order received from the timestamps.

17. A method according to one of claims 13 to 16 characterized by time synchronization based on a signal received from a timestamp packet.

18. Conversion means for converting a packaged flow of signals d information representing separately accommodated information, consecutive packets of digital format data into a stream of information signals with hor markings comprising, an input terminal for receiving the flow in series of information signals; detection means for detecting the data packet in the serial stream received from information signals; means of time to establish a time of arrival of detected data packages; means of generating hour marks to generate data of the hour marks related to the time of arrival; characterized in that, the conversion means includes even more: grouping means for grouping a plurality of the data generated from the mark d the time in a packet of timestamps; a signal generating means of a time stamp packet to generate a signal of the time stamp packet representing the time stamp packet; a transmission means for transmitting the serial flow of signals received d information together with the signals generated from the packet of the time stamps so that a unique association can be established between the data of the time stamps and the packet corresponding data.

19. Conversion means according to claim 18 wherein the conversion means is adapted to process data packets comprising a fixed number of N digital data units and the time stamp signal generator means is adapted to generate data of time stamps comprising a number of N digital data units with M < N characterized in that the signal generating means of the time stamp packet is adapted to generate a signal of the time packet representing a data packet of the time stamps comprising N digital data units.

20. Conversion means according to claims 18 or 19 characterized in that the signal generating means of the time stamp packet is adapted to provide the data packet of the time stamps with identification information.

21. Conversion means according to one of claims 14, 17 or 16 characterized in that the signal generating means of the time stamp packet is adapted to provide each time stamp in the data packet of the time stamps with association information that indicates the corresponding data package.

22. Conversion means according to one of claims 18, 19 or 20, characterized in that the grouping means is adapted to order the plurality of the data of the time stamps within a data package of the time stamps of according to the order of transmission of the corresponding data packets by the transmission medium.

23. Conversion means according to one of claims 18 to 22, characterized in that the grouping means is adapted to group in a data package of the hour marks only those data of the hour marks corresponding to data packets constituting a logical block of combined data packets with the data packet of the timestamps, as used for coding or decoding purposes.

24. Conversion means according to claim 23 characterized in that the logical block of data packets corresponds to a block, as used for error coding or error correction.

25. Conversion means according to claim 23, wherein a sequence of data packets represents a video encoded movie characterized in that the first data packet of a movie corresponds to the first data packet of a logical packet of data packets .

26. Conversion means according to claim 23, wherein a sequence of data packets represents a video encoded movie characterized in that the logical packet of data packets is selected according to a group of video movies.

27. Conversion means according to one of claims 18 to 23, characterized in that the transmission means is adapted to transmit a timestamp packet signal for synchronization of the time of a receiving device via a transmission channel .

28. Conversion means according to claim 24, characterized in that the transmission means is adapted to transmit a synchronization signal that precedes the transmission of a logical block of data packets.

29. Conversion means according to one of claims 20 to 28, characterized in that the conversion means is adapted to receive and transmit information signals representing data packets formatted according to MPEG transport flow packets of N = 188 bytes and to group the data of the timestamps into a data packet of timestamps of N = 188 bytes.

30. Conversion means for converting a stream of information signals representing separately accommodated information, consecutive packets of digital format data with timestamp packet signals generated according to one of claims 1 to 12 in a packaged flow of information signals characterized in that the conversion means comprises: an input terminal for receiving the serial flow of information signals and signals of a packet of timestamps; a detection means for detecting signals received from a packet of timestamps; a separation means for separating the signals from the time stamps of the detected signals from the packet of the time stamps; an association means for associating a signal separated from the timestamps with an information signal representing a corresponding data packet; a determining means for determining a time stamp based on the signal separated from the time stamp; a generating means for generating a synchronization signal based on the time stamp representing a time of transmission of the data packet: a transmission means for transmitting the information signal representing the data packet synchronized by the signal generated from synchronization.

31. Conversion means according to claim 30, characterized in that the detection means is adapted to detect the signals received from the timestamps based on the identification information that accompanies the data package of the time stamps.

32. Conversion means according to claims 30 or 31 characterized in that the association means is adapted to associate a signal separated from the time stamp with an information signal of a corresponding data packet based on the association information accompanies the signal of the hour mark.

33. Conversion means according to one of claims 39 or 30, characterized in that the association means is adapted to associate a signal separated from the time with an information signal of a corresponding data packet based on the received order of the marks of the hour.

34. Conversion means according to one of claims 30 or 33 characterized in that the transmission means is adapted to synchronize in time based on the signal of the packet of the time stamps.

35. A system for storing and removing a packaged stream of information signals representing separately accommodated information, consecutive packets of digital format data, and the system comprising: an input terminal for receiving information signals; a first conversion means according to one of claims 18 or 2 connected to the input terminal; a storage medium connected to the first conversion means for storing signals converted and output by the first conversion means; a second conversion means according to one of claims 30 or 3 connected to the storage means for receiving the stored signals and an output terminal connected to the second conversion means for drawing signals converted by the second conversion means.

36. A system according to claim 35 characterized in that the conversion means is connected to the storage means with a bar adapted to transport signals according to the same format as the signals received d information.

37. A system according to claim 36 adapted to receive information signals representing packets formatted according to a MPEG transport flow packet of N = 188 bytes characterized in that the interconnecting bar is adapted to carry signals representing packets of N = 188 bytes.

38. A system for storing and withdrawing a packaged stream of information signals representing separately accommodated information, consecutive packets of digital format data, and the system comprising: an input terminal for receiving the information signals; a general means for processing data connected to the input terminal for converting signals according to one of claims 1 to 12; a storage medium connected to the general means for processing data to store signals converted and output by the general means for processing data; wherein the general means for processing data is connected to the storage means for receiving and converting the stored signals according to claim 13 and where the system further comprises: an output terminal connected to the general medium to process data to get the signals stored and converted.

39. A packaged stream of information signals comprising data packets and time stamp packets, as obtained according to one of claims 1 to 12.

40. A method for transmitting a packetized flow of information signals which represent information arranged separately, consecutive data packets of digital format by means of a transmission bar adapted to carry signal in accordance with the digital format of the flow of information signals packaged by the flow conversion of information signals into a flow of information signals with signals of the time stamps according to one of claims 1 to 12 and the subsequent transmission of this signal flow d transmission with The packets of the hour marks through the transmission bar.

41. A signal comprising a serial flow of information signals and packet signals of the timestamps, information signals representing separately accommodated information, consecutive packets of digital format data signals of time stamp packets representing a packet of timestamps of grouped data of time stamps of various data packets.