KR20010038361A - Location information recording management method for trick mode support - Google Patents

Abstract

PURPOSE: A position information recording/managing method for trick mode supporting is provided to effectively support a trick play when a digital stream input in realtime is stored in a random access memory. CONSTITUTION: A digital stream controller(20) is connected to a channel circuit(10) and an IEEE1394(40) to receive MPEG TS(transport stream). The channel circuit(10) is a functional block equipped in accordance with the kinds of channels, and compresses a demodulator and an error corrector. That is, the channel circuit(10) receives broadcasting signals transmitted through an inherent channel to convert the signals into the MPEG TS. The IEEE1394(40) transmits single bit stream transmitted from a 1394 network(30) to the digital stream controller(20). An HDD interface(60) interfaces the TS between an HDD(70) and a memory(90).

Description

LOCATION INFORMATION RECORDING MANAGEMENT METHOD FOR TRICK MODE SUPPORT}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a broadcast reception system capable of simultaneously supporting time delay viewing and recording and playback of a broadcast signal. More particularly, the present invention relates to a method of recording and managing location information of a picture type recorded to support a trick mode.

The hard disk drive, which is a secondary memory device of a computer system, can be randomly accessed, and the data transmission speed is high, and it can be cheaper and larger in capacity than other auxiliary memory devices. It is used as an access storage device.

A broadcast receiving system having a random access storage device is a system capable of simultaneously recording and playing back digital transport streams and viewing time delays. Simultaneous recording and reproducing of the time-delayed viewing and transport stream of the broadcast signal can be implemented by buffering the digital stream input / output to the hard disk drive.

A general broadcast reception system capable of supporting time delay viewing and recording and playback of a broadcast signal simultaneously performs A / D conversion of the received analog broadcast signal to store a digital transport stream on a hard disk, and then converts it into MPEG. The encoder converts the digital video stream and stores it on the hard disk. Therefore, a general broadcast reception system requires an additional hardware configuration such as an A / D converter and an MPEG encoder in order to store a digital stream on the hard disk surface, so that the broadcast reception system is enlarged.

In addition, considering multimedia products such as multimedia PC, video on demand (VOD), high definition TV, digital broadcasting, digital communication, and so on, the real-time transmission of digital streams is stored on the hard disk and supports time delay and trick play. To do this, a controller for effectively controlling the input and output of the digital stream is required.

And in order to support the trick mode, it is necessary to know the location information of the recording data recorded on the hard disk surface to support the trick mode.

Accordingly, an object of the present invention is to provide a method of recording and managing location information of recorded data to efficiently support trick play in storing a digital stream input in real time on a recording medium of a random access storage device.

The present invention for achieving the above object is a location information recording management method for trick mode support in a broadcast receiving system having a random access storage device,

Extracting a video transport packet of a recording channel from an input transport stream, finding a picture header from the extracted video transport packet, and setting picture type information;

A second process of composing a plurality of the video transport packets into one disc packet and recording them on a disc surface;

And a third step of creating a picture type table by matching the recording position information on the disc for each picture type constituting the disc packet, searching for a table created when the trick mode is supported, and reading only desired data. It is done.

1 is a block diagram of a broadcast receiving system having a digital stream controller according to an embodiment of the present invention.

2 is a block diagram of the digital stream controller 20 in FIG.

3 is a disk packet structure diagram according to an embodiment of the present invention.

4 is an exemplary disk packet size in accordance with an embodiment of the present invention.

5 is a diagram illustrating a picture type table configuration for trick mode support according to an embodiment of the present invention.

Hereinafter, a method of recording location information for supporting a trick mode according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

First, FIG. 1 illustrates a block diagram of a broadcast receiving system having a digital stream controller required to support a trick mode according to an embodiment of the present invention. FIG. 2 is a detailed diagram of the digital stream controller 20 of FIG. The configuration diagram is shown. 1 and 2 are attached to a patent application filed by the applicant of the Korean Patent Office in 1999 under the name "Digital Stream Controller and Broadcast Receiving System Including It".

Referring to FIG. 1, a digital stream controller 20 according to an exemplary embodiment of the present invention is connected to a channel circuit 10 and an IEEE 1394 40 to receive an MPEG transport stream. The channel circuit 10 is a functional block that must be provided according to channel types such as terrestrial waves, satellites, cables, etc., and includes a demodulator for demodulating a modulated signal and an error correction unit for correcting errors accompanying transmission. It includes. That is, the channel circuit 10 inputs a broadcast signal transmitted through a unique channel, converts it into an MPEG transport stream (hereinafter referred to as a TS stream), and outputs it.

The IEEE 1394 40 transmits a single bit stream transmitted from the 1394 network 30 to the digital stream controller 20.

The digital stream controller 20 inserts new PAT information and time stamps into the TS stream input from the 1394 network or the channel circuit 10 and transmits the new PAT information and time stamps to the memory 1 90 through the PCI bus 50 and the HDD 70. Transmits the TS stream reproduced from the A / V decoder according to the value of the time stamp inserted in the storage.

The HDD interface 60 interfaces TS streams transmitted and received between the hard disk drive (HDD) 70 and the memory 1 90.

The HDD 70 includes a plurality of disks for recording and storing TS streams transmitted through the HDD interface 60, and heads for recording TS packets or reading recorded TS packets on the disk surface.

The bridge circuit 80 converts signals between the intrinsic bus of the system controller 100 and the PCI bus 50 to enable transmission and reception of signals. That is, when the system controller 100 wants to write data to a function block existing on the PCI bus, the system controller 100 converts the intrinsic bus signal into a PCI bus signal to exist on the PCI bus 50. Allows to write to the block.

The memory 1 90 is a disk packet controlled by the system control unit 100 and stores a 192 byte TS packet including a time stamp (4 bytes) transmitted from the digital stream controller 20 or reproduced from the HDD 70. Temporarily save.

The system controller 100 includes a memory configured to include a RAM for temporarily storing data generated during a system control operation and a ROM in which system control program data is stored. The system controller 100 is connected to a user interface unit (such as a remote control unit or an operation panel unit) 110 to perform a series of control operations for simultaneously supporting time delay viewing and recording and playback according to a user's operation command. For example, the system controller 100 controls a disk packetized TS packet stored in the memory 1 90 to be transmitted to the HDD 70, and controls the disk packet reproduced from the HDD 70 to be stored in the memory 1 ( 90) to be stored. In addition, the system controller 100 creates a picture type table for trick mode support during TS stream recording and stores the picture type table in the internal memory. In another embodiment, the picture type table may be recorded in the maintenance area of the disk, and then read and updated by the system controller 100 when the drive is initialized.

Since the configuration of the picture type table is illustrated in FIG. 5, a detailed description thereof will be described later.

2, the digital stream controller 20 includes a transport stream (TS) demux (DEMUX) 21, a PAT inserter 22, a time stamp inserter & PH (picture header) detector 23. ), A DMA controller 24, a FIFO memory 25, and a timing controller 26.

The TS DEMUX 21 is composed of a PID filter 21a and a scrambler 21b. The PID filter 21a selects and outputs only PIDs necessary for recording only a single channel to be recorded on the HDD. If the channel is changed by the user's selection, the PID value of the changed channel is newly set by the control of the system controller 100. The PID to be selected includes a program association table (PAT), a program map table (PMT), a video PID, an audio PID, a data PID, and an ECM PID.

The scrambler 21b scrambles and outputs the AV stream transmitted from the IEEE 1394 network. That is, the scrambler 21b exists to scramble the unscrambled AV stream. If the input channel is scrambled, the scrambler 21b bypasses the scrambler 21 without having to scramble it again. Such control is performed by the control of the system control unit 100.

The PAT inserting unit 22 generates a new PAT packet having only the information on the currently selected channel at the time when the PAT having the information on the various channels on the air arrives and inserts the new PAT packet into the TS stream.

In the time stamp inserting unit & PH detecting unit 23, the time stamp inserting unit captures an internal counter value which is incremented by 27 MHz clock upon arrival of the TS packet and inserts it into the input TS packet. By inserting the time stamp into the TS packet as described above, the HDD 70 is initialized with the time stamp inserted into the first TS packet during playback, and then the time stamp value inserted into the next TS packet is compared with the internal counter value which is continuously increasing. If the same, the TS packet can be transmitted. The time stamp is assumed to have a size of 4 bytes in the following description.

The picture header (PH) detection unit in the time stamp insertion unit & PH detection unit 23 sets the video PID value of the internal register under the control of the system control unit 100. The PH detection unit finds a picture header in a video TS packet, sets a picture header detection bit, and simultaneously sets picture type information of a current picture. The picture header detection bit set as described above is used when configuring the header information for recording the disk packet on the HDD 70.

The DMA controller 24 transmits the TS packet inputted from the time stamp inserting unit & PH detecting unit 23 to the memory 1 90 and stores the disk packet stored in the memory 1 90 under the control of the system control unit 100. Only valid data (TS packets with time stamps except headers) are read out and transferred to the target memory 25. The DMA controller 24 has a plurality of registers therein. For example, the DMA controller 24 has two registers for DMA transfer of an input TS packet. That is, DMA operation is performed by using a pair of registers, and after the interrupt is generated, TS packets are continuously transmitted using the remaining pair of registers automatically. In order to perform this process smoothly, not only the register set related to the DMA has two pairs, but the register for reporting the result of processing by the PH detection unit also has two pairs and is used in connection with the aforementioned DMA register.

The PoBee memory 25 temporarily stores the TS-packet inserted into the TS packet input through the DMA controller 24 and outputs the first-in first-out method.

The timing controller 26 reads out the TS packet having the time stamp inserted from the packet memory 25 and outputs 188 bytes of TS packet excluding the time stamp to the A / V decoder when the time written in the time stamp is reached. .

Hereinafter, a process of disc packetizing and recording a TS stream input from a channel to the HDD 70 for trick mode support will be described in detail with reference to FIGS. 3 to 5.

First, FIG. 3 illustrates a structure of a disk packet according to an embodiment of the present invention, and FIG. 4 illustrates an exemplary diagram of a disk packet size according to an embodiment of the present invention. 5 illustrates an example of a picture type table for trick mode support according to an embodiment of the present invention.

A disk packet according to an embodiment of the present invention refers to a group of TS packets recorded on a disk surface, and is divided into a header part and data. The data consists of a TS packet and a time Tn when each TS packet arrives. The arrival time of the TS packet refers to the value of the inserted time stamp. The reason for constructing the disk packet as described above is to improve the speed at the time of data access by aligning and writing successive TS packets in successive sectors of the disk surface. The registers in the DMA controller 24 for storing the data in the memory 1 90 and disk packetizing are as shown in Table 1 below.

Register name Explanation Disk packet start address Start address when saving TS packet to memory 1 TS packet size MPEG: 192 TS Packet Count Number of TS packets that need to be sent to construct disk packets Control / command

That is, 192 bytes of TS packets including the time stamps from the DMA controller 24 can be collected in the memory 1 90 to generate one disk packet. In this case, the size of the disk packet can be varied as shown in FIG. Can be. The larger the size of the disk packet, the more space for storing the TS packet is required in the memory 1 90. Since several pictures may exist in one disk packet, it is desirable to determine the size of the disk packet in consideration of this point. .

Meanwhile, the header, which is an element of the disk packet, may have items as shown in Table 2 below.

Header Information Number of bytes Explanation Header 2 Disk packet header Validity of header information One Data validity flag PMT PID 2 each (optional) PSI Information for Single Program Video PID Audio PID ECM PID Data PID Random access indicator One Whether to include picture header and whether to include I picture TS Pointer Indicates which TS packet among n TS packets has a picture header. Picture header type One Time Key size One The size of the encrypted key Encrypted Key One Key to unlock if TS is scrambled

In Table 2, information such as a random access indicator, a TS pointer, and a picture header type is set using information transmitted from the PH detector 23.

On the other hand, a picture type table is created in order to disk packetize TS packets and support trick mode (fast forward, rewind) operation. The picture type table is arranged according to the video transport packet order as illustrated in FIG. 5. It is created and stored and used in internal memory. In FIG. 5, C, H, and S indicate a position value of a disk surface on which a picture header is stored, and represent cylinder, head, and sector numbers, respectively. As shown in FIG. 5, by creating and operating a picture type table, fast forward and fast rewind can be efficiently performed. For example, if a fast forward is performed in the trick mode, the system controller 100 searches the picture type table to determine the location information values C, H, and S for the I picture or P picture closest to the current picture. ) And transferred to the HDD interface 60, only the required picture data can be read from the disk surface. On the contrary, even when fast rewinding is performed, fast rewinding can be normally performed by reading and playing back data existing between the picture header of the I picture and the picture header of the previous I picture that advance in time from the current picture position.

Hereinafter, a process of packetizing a 192-byte TS packet including a time stamp into a 2K-byte disk packet to record and store in the HDD 70 will be described.

First, when a command for recording a digital broadcast signal to the HDD 70 is input through the user interface 110, the system controller 100 needs to record only a selected (or changed) broadcast channel (eg, a PID value). Set them). After the channel selection or change process, the TS stream output from the PID filter 21a is output through the scrambler 21b, and a new PAT packet having only information on the channel selected by the PAT inserter 22 is inserted. The time stamp inserting unit & PH detecting unit 23 inserts a time stamp indicating the TS packet arrival time, and is sequentially transferred to the memory 1 90 via the DMA controller 24. During the DMA transfer, the DMA controller 100 designates a TS packet storage location (address) of the memory 1 90, and then transfers a group of TS packets to the memory 1 90 by transferring the input TS packets to the memory 1 90. Sequentially transmit to (90). If one group of TS packets is completed, the DMA controller 24 generates an interrupt to the system controller 100. The group of TS packets may be defined as ten TS packets constituting a disk packet in the following description.

On the other hand, when an interrupt occurs, the system controller 100 inserts a picture header (detected by the PH detection unit) into a group of TS packets to make a complete disk packet, and then designates a disk storage location (C, H, S or Logic Block Address). do. When the storage location of the disk packet is specified as described above, the system controller 100 transmits the disk packet to the HDD 70 to record and store the picture and to update the picture type table. Since TS packets are DMA-transmitted continuously during the transmission of such disk packets, two pairs of registers related to the DMA transfer are performed to perform one pair of DMA transfers, and after the interrupt is generated, the remaining one pair of registers is automatically used. Allow TS packets to be sent.

Therefore, a group of TS packets transmitted from the DMA controller 24 is disk packetized under the control of the system control unit 100 and recorded and stored in a predetermined position of the HDD 70, and the storage position of each picture type is stored in the picture type table. By updating, the system controller 100 can read the location information of each picture stored in the internal memory to support the trick mode.

As described above, the present invention has an advantage of easily supporting trick play by managing the picture data recorded on the disk surface and the location information corresponding thereto in a table.

Claims (4)

In the location information recording management method for trick mode support in a broadcast receiving system having a random access storage device, Extracting a video transport packet of a recording channel from an input transport stream, finding a picture header from the extracted video transport packet, and setting picture type information; A second process of composing a plurality of the video transport packets into one disc packet and recording them on a disc surface; And a third step of creating a picture type table by matching the recording position information on the disc for each picture type constituting the disc packet, searching for a table created when the trick mode is supported, and reading only desired data. Location information record management method for trick mode support. The method of claim 1, wherein the recording position information on the disc in the picture type table comprises a cylinder number, a head number, and a sector number. The method of claim 1, wherein the picture type table is stored in a maintenance area of the disk surface. The method of claim 1, wherein the picture type table is prepared based on an input video transport packet order.