JPH08205092A - Computer system - Google Patents

Abstract

PURPOSE: To display moving image data of high definition for sub-video image and audio signal through simple configuration. CONSTITUTION: An SD-ROM drive 21 stores moving image data with sub-video image and an audio signal. The SD-ROM drive 21 connects to an SCSI interface 16 and uses a data buffer 162 of the SCSI interface 16 to transfer an MPEG stream to an MPEG2 decoder 18 on a system board at a variable speed. Thus, the configuration required for moving image reproduction is simplified and the moving image data with a sub-picture and an audio signal are displayed with high image quality.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a computer system, and more particularly to a disk drive device for driving a recording medium having a high recording density in which moving image data and audio data including a main image and a sub image are digitally compressed and recorded. The present invention relates to a multimedia-compatible computer system for displaying moving images and reproducing audio by using.

[0002]

2. Description of the Related Art With the recent development of computer technology,
Various so-called multimedia-compatible personal computers have been developed. This type of personal computer can reproduce moving image and audio data in addition to text data and graphics data.

Usually, moving image data is compressed and encoded by MPEG1 and stored in a CD-ROM or the like, and a dedicated expansion board is used for decoding and displaying / reproducing the moving image data. As an expansion board for decoding and displaying / reproducing moving image data, for example, “REAL Magic” manufactured by Sigma Design Co. of the United States is well known. This "REAL Magic" is MPEG1
It has a video decoding function in conformity with the standard, and the decoded moving image data is displayed after being combined with the VGA graphics captured from the video card via the feature connector.

However, the MPEG1 standard is 1.5 Mb.
This is a standard on the assumption that a CD-ROM having a data transfer rate of about ps is used, and handling moving image data including a large amount of image information such as a movie causes a problem such as deterioration of image quality.

Therefore, recently, a new generation storage medium having a data transfer rate which is several times to several tens times that of a CD-ROM has been developed. As such a new generation storage medium, a system capable of digitally recording an information amount of about 10 GB on one disk and realizing a data transfer rate of about 10 Mbps at maximum has been proposed as a media player.

This media player records moving image data and audio data, which are digitally compressed and coded according to the MPEG2 standard, on a disk medium such as an optical disk, decodes the moving image data with audio, and outputs the decoded data to a television receiver. It is what is output.

This media player is provided with a disk drive device, a data buffer, a video decoder, an audio decoder, an NTSC encoder and the like. In this media player, the optical disc is driven by the disc drive device to read moving image data and audio data from the optical disc.
It is stored in the data buffer.

The moving image data and audio data stored in the data buffer are decoded by a video decoder and an audio decoder, respectively. The moving picture data decoded by the video decoder is converted into an NTSC signal by the NTSC encoder and sent to the video input of the television receiver. On the other hand, the audio data decoded by the audio decoder is D / A converted and then sent to the audio input of the television receiver.

Since the data transfer rate of this media player is as extremely high as about 10 Mbps, as described above, when this media player is used, in addition to the main video, sub-video such as subtitles and a movie including a plurality of audio channels are provided. Information can be recorded on a single disc having a size similar to that of a CD, and the main video, sub-video and audio can be synchronized and reproduced on a television receiver.

However, when this media player is mounted on a personal computer, it is necessary to provide a video decoder and the like inside the system of the personal computer in addition to the media player.

This is because the video decoder inside the media player is dedicated to that player, and media other than the media player, such as a hard disk or a CD, is used.
This is because the MPEG title recorded in the ROM or the like cannot be decoded using the video decoder inside the player.

Therefore, when a system in which a media player is installed in a personal computer is constructed, a video decoder for reproducing a moving image is provided twice inside the system, which raises the cost of the entire system.

[0013]

As described above, recently, a media player having a large capacity and a high transfer rate has been proposed, but since the video decoder inside the media player is dedicated to that player, Even if the player is installed in a personal computer, it is not possible to reproduce moving picture titles stored in other media. Therefore, when a system in which the media player is installed in a personal computer is constructed, a video decoder for playing back a moving image is provided twice inside the system, which causes a cost increase of the entire system.

The present invention has been made in view of the above circumstances, and realizes an optimum system for reproducing large-capacity multimedia information including main video, sub-video, and audio data on a personal computer. Therefore, it is an object of the present invention to provide a computer system which can perform high-quality moving image reproduction at low cost without providing a double video decoder for reproducing moving images inside the system.

[0015]

Means and Actions for Solving the Problems
In a computer system capable of connecting to a disc drive device capable of driving a recording medium in which moving picture data with sub-picture is digitally compressed and encoded, the computer system is connected to a bus of the computer system, and is read from the disc drive device. A video decoder for decoding moving picture data included in the issued digital data string; a sub-video decoder connected to the bus for decoding sub-picture data included in the digital data string read from the disk drive device; and the bus A display controller for controlling a display monitor of the computer system, the display controller receiving the decoded moving picture and sub-picture, and displaying moving picture data with the sub-picture on the screen of the display monitor. Characterized by comprising a roller.

The disk drive device used in this computer system is composed not of the entire media player described above but only of the part corresponding to the disk drive unit of the media player, and the recording medium of the disk drive unit is mainly composed of A large amount of moving image data and audio data including video and sub-video are encoded and stored by high-efficiency digital compression encoding such as MPEG2 standard.

The encoded moving picture data and sub-picture read from the disk drive unit are decoded by a video decoder and a sub-video decoder provided inside the system, respectively.

As described above, in this system, the moving picture data and the sub video are not decoded inside the media player as in the conventional case, but the decoding of the data is performed by the video decoder and the sub video decoder provided inside the system. Executed respectively. Since these video decoder and sub video decoder are connected to the system bus, not only the encoded data read from the disk drive unit but also the hard disk and C
The D-ROM can also be used to decode encoded data read from any other recording medium.

The moving image data decoded by the video decoder is transferred to the display controller and displayed on the screen by the display controller. Therefore, it is not necessary to use the expansion board dedicated to the moving image reproduction as described above.

Therefore, it is possible to realize an optimal system for reproducing large-capacity multimedia information composed of moving picture data with sub-pictures, audio data, etc. on a personal computer. Therefore, it is possible to perform high-quality video reproduction without providing dual video decoders or the like inside the system or using an expansion board dedicated to video reproduction.

Further, the disk drive unit is preferably connected to the computer system via a peripheral interface device having a data buffer, such as a SCSI interface.

Since the encoding process of the MPEG2 standard is variable speed encoding, if the moving image data encoded by MPEG2 is stored in the recording medium of the disc drive device, it is read out from the disc drive device. The transfer rate of the bit stream of the MPEG data is variable. To support this variable transfer rate,
It is necessary to use a data buffer to transfer moving image data from the disk drive device to the video decoder. The above-mentioned media player has a built-in data buffer, but if the disk drive unit is connected to the computer system via a peripheral interface device having a data buffer, the data buffer of the peripheral interface device is used to make the disk drive device. The video data can be transferred from the video decoder to the video decoder at a variable speed.

Therefore, not only the decoder but also the data buffer can be eliminated from the disk drive device, and a cheaper system can be realized. Further, when realizing moving image reproduction on a laptop type or notebook type personal computer, it is preferable to realize the above-mentioned video decoder and audio decoder by a card such as a PC card. Even in this case, as long as the card is installed, as in the case where the video decoder and the audio decoder are connected to the bus, the decoder can also decode the encoded data read from other recording media such as a hard disk. Can be used.

[0024]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows the system configuration of a personal computer according to an embodiment of the present invention. This system corresponds to a desktop personal computer, and as shown in the figure, the system bus 10, C
PU11, system memory (MEM) 12, HDD1
3, FDD 14, keyboard (KB) 15, SCSI interface 16, audio controller 17, MP
EG2 decoder 18, multimedia display controller 19, and video memory (VRAM) 20
The SD-ROM drive 21 that stores the moving image data encoded by MPEG2 is
It is connected to the SI interface 16.

SD-ROM (Super Densit)
y ROM) drive 21 corresponds to the disc drive unit of the media player described above,
Both sides of the disk have a storage capacity of about 10 GB and a maximum data transfer rate of about 10 Mbps. This SD
The ROM drive 21, as shown in FIG.
Optical disk 211, motor 212, pickup 2
13, pickup drive 214, servo controller 215, ECC for error detection and correction
And a drive controller 216 including a circuit. The motor 212, the pickup 213, the pickup drive 214, the servo controller 215, and the drive controller 216 function as a drive device for driving the optical disc 211 and reading the data recorded on the optical disc 211.

The optical disc 211 has, for example, one side with one side.
A movie of about 35 minutes can be recorded. This movie information can include main video (video), sub-video up to 16 channels (sub-picture), and audio up to 8 channels (audio).

In this case, these videos, sub-pictures,
And audio are digitally encoded and recorded according to the MPEG2 standard. In the MPEG2 standard, M
The data coded by PEG2 can include other coded data, and these coded data are handled as one MPEG bit stream (digital data string).

Therefore, in this embodiment, MPEG2 is used for video coding, and run-length coding and D coding are used for sub-picture and audio coding, respectively.
OLBY AC3 shall be used. Even in this case, the encoded video, sub-picture, and audio are treated as one MPEG bit stream.

The MPEG2 standard coding process is variable speed coding, and the data transfer rate can be varied.
Therefore, with respect to video data, the amount of information recorded / reproduced per unit time can be made different. Therefore,
Higher quality moving images can be reproduced by increasing the transfer rate of the MPEG bit stream forming the frame group corresponding to the more dynamic scenes.

In order to utilize the characteristics of MPEG2 as described above, in this embodiment, the movie information is recorded on the disk 211 by using the data format shown in FIG.

As shown in FIG. 3, one piece of movie information is composed of a file management information section and a data section, and the data section has a large number of data blocks (block # 0).
~ # N) are included. D at the beginning of each data block
There is an SI (Disk Serh Information) pack, and one data block is from the DSI pack to the next DSI pack. The storage location of each DSI pack is managed by the disc search map information in the file management information section.

One data block constitutes information of 15 frames necessary for reproducing a moving image for a certain fixed time, for example, 0.5 seconds, and GOP (Group of of
picture). Each data block contains
Video pack (VIDEO pack), sub-picture pack (SP pack), and audio pack (AUD)
(IO pack) is recorded in a multiplexed form. These video packs (VIDEO packs), sub-picture packs (SP packs), and audio packs (AUDI)
O pack) is a data unit of encoded video, sub-picture, and audio. The data size of these packs is fixed, but the number of packs that can be included in one data block is variable. Therefore, a larger number of video packs are included in a data block corresponding to a scene with a lot of motion.

The video pack, sub-picture pack, and audio pack each include a header part and a packet part (video packet, sub-picture packet, audio packet). The packet part is the encoded data itself. The header portion is composed of a pack header, a system header, and a packet header. A stream ID indicating whether the corresponding packet is a video packet, subpicture packet, or audio packet is registered in the packet header. .

Next, each unit of the system shown in FIG. 1 will be described. The CPU 11 controls the operation of the entire system, and executes the operating system and the application programs to be executed, which are stored in the system memory (MEM) 12. SD-ROM
The reproduction of the movie recorded in the drive 21 is executed by causing the CPU 11 to execute the moving image reproduction driver.

The SCSI interface 16 is a peripheral interface for connecting a peripheral device such as an HDD or a CD-ROM to the system bus 10. In this embodiment, data between the SD-ROM drive 21 and the MPEG2 decoder 18 is used. Transfer. The SCSI interface 16 includes a SCSI controller (S
CSI CONT) 161, and data buffer (B
UFF) 162 is provided. The SCSI controller 161 responds to the SD command in response to a command from the CPU 11.
Control the data transfer with the ROM drive 21.
The data buffer (BUFF) 162 is used for varying the data transfer rate with the host system, and the MPEG stream including video, sub-picture, and audio read from the SD-ROM drive 21 is a data stream. It is transferred to the MPEG2 decoder 18 via the buffer (BUFF) 162.

In this case, the data transfer rate from the SD-ROM drive 21 to the data buffer 16 is SD-RO.
Maximum data transfer rate of M drive 21, eg 9.5
It runs at Mbps.

On the other hand, from the data buffer 16 to MPEG2
The data transfer speed to the decoder 18 is variable, and the average transfer speed at that time becomes faster as the data block having a large amount of information is transferred. This is because the data transfer from the data buffer 16 to the MPEG2 decoder 18 is
This is because under the control of 11, the decoding processing operation of the MPEG2 decoder 18 is performed in synchronization, and the data block having a larger amount of information increases the number of times of data transfer executed per fixed time.

The audio controller 17 is the CPU 1
The sound data input / output control is performed under the control of No. 1 and the PCM sound sources 171 and F are used for sound output.
An M sound source 172, a multiplexer 173, and a D / A converter 174 are provided. Outputs from the PCM sound source 171 and the FM sound source 172 and digital audio data transferred from the MPEG2 decoder 18 are input to the multiplexer 173, and one of them is selected.

The digital audio data is SD-RO.
The audio data read from the M drive 21 is decoded. The audio bus 18a is used to transfer the digital audio data from the MPEG2 decoder 18 to the audio controller 17, and the system bus 10 is not used. Therefore, high-speed transfer of digital audio data becomes possible.

The MPEG2 decoder 18 includes the CPU 11
Under control of the SCSI interface 16 receives the MPEG bitstream transferred from the SD-ROM drive 21 via the data buffer 162, separates it into video, subpicture, and audio packets and then Each is decoded, synchronized and output.

The decoded audio data is transferred to the audio controller 18a via the audio bus 18a as digital audio data as described above. The decoded video and sub-picture are combined and sent to the multimedia display controller 19 as digital YUV data. In this case, the video bus 18b is used to transfer the digital YUV data from the MPEG2 decoder 18 to the multimedia display controller 19, and the system bus 10 is not used. Therefore, the transfer of the digital YUV data is similar to the digital audio data.
It can be done at high speed.

As the video bus 18b, a VAFC (VESA Advanced Feature) of VESA standard is used.
reConnector), or VM-Channel
el (VESA Media Channel) can be used.

The multimedia display controller 19 controls the CRT display used as a display monitor of this system under the control of the CPU 11, and supports the VGA specification text and graphics display as well as the moving image display. .

As shown in the figure, the multimedia display controller 19 includes a graphics display control circuit (Graphics) 191, a video display control circuit 192,
The multiplexer 193 and the D / A converter 194
Etc. are provided.

The graphics display control circuit 191 uses V
It is a GA compatible graphics controller and converts VGA graphics data drawn in the video memory (VRAM) 20 into RGB video data and outputs the RGB video data.
The video display control circuit 192 includes a video buffer that stores digital YUV data, and Y stored in the buffer.
YUB-R that converts UB data into RGB video data
It has a GB conversion circuit and the like.

The multiplexer 193 selects one of the output data of the graphics display control circuit 191 and the video display control circuit 192, or outputs the video output from the video display control circuit 192 on the VGA graphics from the graphics display control circuit 191. The synthesized data is sent to the D / A converter 194. The D / A converter 194 converts the video data from the multiplexer 194 into an analog RGB signal and outputs it to a CRT display.

FIG. 4 shows a concrete structure of the MPEG2 decoder 18. The MPEG2 decoder 18 includes three decoders corresponding to video, subpicture, and audio, that is, an MPEG2 video decoder 181 in order to synchronously decode and reproduce the multiplexed video, subpicture, and audio bitstreams. , A sub-picture decoder 182, and an audio decoder 183.

These MPEG2 video decoders 18
1, sub-picture decoder 182, and audio decoder 183 are each coupled to system bus 10 via an internal bus. The MPEG2 video decoder 181 and the sub-picture decoder 182 have RAMs 184 and 185, respectively, used for decoding processing and the like.
Is provided.

The MPEG2 video decoder 181 is for decoding the video data included in the multiplexed MPEG stream, and repeatedly sends a transfer request until the MPEG stream for one data block is received from the SCSI interface 16. Issue.
The MPEG2 video decoder 181 uses the stream ID described in FIG. 3 to separate the received MPEG stream into video, sub-picture, and audio for each pack, and decodes the video pack. M
The sub-picture and audio pack separated by the PEG2 video decoder 181 are sent to the sub-picture decoder 182 and audio decoder 183, respectively.

As described above, the decoding reproduction time corresponding to one data block is fixed, and the amount of information contained in one data block is variable. Therefore, MP
The number of transfer requests generated until the EG2 video decoder 181 receives an MPEG stream of one data block increases as the data block has a larger amount of information, and the average transfer rate of the MPEG stream increases.

The sub-picture decoder 182 is an MPEG
2 The sub-picture pack separated by the video decoder 181 is decoded. The type of decoding process executed here corresponds to the encoding process applied to the sub-picture, that is, the run-length encoding.
Further, the sub-picture decoder 182 receives the video decoded by the MPEG2 video decoder 181, and
The sub picture decoded by the sub picture decoder 182 is combined with the video. The composite position of the sub-picture is determined by the position information included in the header section added to the sub-picture packet. The combined data is output as debatal YUV data.

The audio decoder 183 is MPEG2.
The audio pack separated by the video decoder 181 is decoded. The type of decoding processing executed here corresponds to the encoding processing applied to the audio data, that is, DOLBY AC3.
The decoded audio packet is output as digital audio data.

Next, with reference to FIG. 5, a movie reproducing operation in the system of FIG. 1 will be described. When the transfer command is issued from the CPU 11, the MPEG stream is read from the SD-ROM drive 21, and the MPEG stream is 9.5 Mb.
The data is transferred to the SCSI interface data buffer 162 at a transfer rate of ps. Then, under the control of the CPU 11, the transfer of the MPEG stream from the data buffer 162 to the MPEG2 video decoder 181 is started.

The average transfer rate in this case is variable as described above, and as shown in FIG. 6, the transfer rate is increased in the period A corresponding to a scene with a lot of motion, and a scene with little motion is displayed. In the corresponding period B, the transfer rate is decreased.

The MPEG video is decoded by the MPEG2 video decoder 181, and restored to the original main video before encoding. A sub-picture such as a subtitle is decoded by the sub-picture decoder 182 to be restored into a character pattern, and the character pattern is synthesized on the decoded MPEG video as illustrated. Further, the audio is decoded by the audio decoder 183 and reproduced.

The video data in which the sub-pictures are combined is sent to the multimedia display controller 19 as digital YUV data, where it is combined in the color key area (illustrated by hatching) of VGA graphics.

In this way, the main image including the subtitles can be displayed on the VGA graphics, and the sound can be reproduced in synchronization with the screen. As described above, in this embodiment, the SD-ROM drive 21 composed only of the drive unit section of the media player described above is used, and the SD-ROM drive 21 stores the moving image data with sub-picture and audio. It is recorded. SD-
The ROM drive 21 is connected to the SCSI interface 16, and the data stream 162 of the SCSI interface 16 is used to transfer the MPEG stream to the MPEG2 decoder 18 on the system board at a variable speed.

Therefore, the structure necessary for reproducing the moving image can be simplified, and the moving image data with sub-picture and audio encoded by MPEG2 can be displayed with high quality.

Next, the system configuration according to the second embodiment of the present invention will be described with reference to FIG. The system of FIG. 7 is obtained by applying the system configuration of the desktop personal computer of FIG. 1 to a notebook type portable computer. The system of FIG. 7 is similar to that of FIG.
Compared with the system of, only the following points are different.

That is, here, the MPEG2 video decoder 18 is realized on the PC card 22 instead of on the system board as shown in FIG. 1, and the PC card controller 23 includes the audio controller 17 and the multimedia display controller 19 respectively. It has an interface with.

The PC card 22 complies with the PCMCIA specification, is mounted in a card slot of the notebook type portable computer main body, and is connected to a PC card interface (connector) in the slot.

The PC card 22 has a CIS (Card Infor
mation structure) 221 and an MPEG2 decoder 222. MPEG2 decoder 22
2 is an MPEG2 video decoder 18 of FIG. 1 except for interfaces with the audio controller 17 and the multimedia display controller 19, respectively.
It has exactly the same function as, and its configuration is as described in FIG.

The PC card controller 23 is the CPU 1
Under control of 1, various Ps installed in the PC card slot
It is for controlling the C card and has two operation modes, mode 1 and mode 2. Mode 1 is for controlling a normal PC card such as a modem card, transfers data between the system bus 10 and the PC card, and does not use the audio bus 18a and the video bus 18b.

Mode 2 is a mode used when the PC card 22 is inserted in the PC card slot. In this mode 2, the PC card controller 21 transfers the MPEG stream to the PC card 22 and also receives the digital audio data and the digital YUV data returned from the PC card 22 via, for example, different signal lines from the audio bus 18a.
And to the audio controller 17 and the multimedia display controller 19 via the video bus 18b.

FIG. 8 shows the configuration of the PC card controller 23. The PC card controller 23 includes a data transfer control logic 231 and a mode register 2
32 is provided, and the operation mode of the PC card controller 23 is switched by setting a mode designation flag in the mode register 232.

The mode specifying flag is set by the CPU 11 when the system power is turned on, for example. That is, the CPU 11 reads the attribute information from the PC card installed in the PC card slot and detects the type of the installed PC card based on the attribute information. If the installed PC card is PC card 22, CP
U11 sets the mode designation flag indicating the mode 2 in the mode register 232.

[0067]

As described above, according to the present invention, the disk drive unit in which the moving picture data with sub-picture and audio is recorded is connected to the SCSI interface, and the data buffer of the SCSI interface is used. , A stream of moving image data is transferred at a variable speed to a video decoder or the like on the system board. Therefore, it is possible to simplify the configuration required for moving image reproduction, and display moving image data with sub-pictures and audio with high quality.

[Brief description of drawings]

FIG. 1 is a multimedia P according to a first embodiment of the present invention.
The block diagram which shows the system configuration of C.

FIG. 2 is an SD-R used in the system of the first embodiment.
The block diagram which shows the structure of OM drive.

FIG. 3 is a diagram showing a recording format of moving image data used in the system of the first embodiment.

FIG. 4 is an MPEG provided in the system of the first embodiment.
2 A block diagram showing an example of a specific configuration of a decoder.

FIG. 5 is a diagram for explaining a moving image reproducing operation in the system of the first embodiment.

FIG. 6 is a diagram showing how the transfer rate of moving image data changes in the system of the first embodiment.

FIG. 7 is a multimedia P according to a second embodiment of the present invention.
The block diagram which shows the system configuration of C.

FIG. 8 is a block diagram showing a configuration of a PC card controller provided in the system of the second embodiment.

[Explanation of symbols]

10 ... System bus, 11 ... CPU, 12 ... System memory, 16 ... SCSI interface, 17 ... Audio controller, 18 ... MPEG2 decoder, 19 ...
Multimedia display controller, 20 ... video memory, 21 ... SD-ROM drive, 22 ... PC card, 23 ... PC card controller, 161 ... SCS
I controller, 162 ... Data buffer, 181 ... M
PEG2 video decoder, 182 ... Sub-picture decoder, 183 ... Audio decoder.

Claims (22)

[Claims] 1. A computer system capable of connecting to a disk drive device capable of driving a recording medium on which moving picture data with sub-pictures is digitally compressed and recorded, said computer system being connected to a bus of said computer system, A video decoder that decodes moving image data included in a digital data string read from the disk drive device, and a sub video that is connected to the bus and decodes sub-picture data included in the digital data string read from the disk drive device. A decoder and a display controller that is connected to the bus and controls a display monitor of the computer system, receives the decoded moving image and sub-picture, and displays moving picture data with the sub-picture on a screen of the display monitor. Display data A computer system comprising a display controller. 2. Digital recording audio data that has been digitally compressed and encoded is multiplexed with the moving image data with the sub-picture and recorded on the recording medium, and is connected to the bus and read from the disk drive device. The computer system according to claim 1, further comprising an audio decoder that decodes audio data included in the data string. 3. The moving image data is variable-speed coded and stored in a recording medium of the disk drive device, and the video decoder decodes the variable-speed coded data. The computer system according to item 1. 4. A peripheral interface device having a data buffer, and using the data buffer to transfer data between the computer system and a peripheral device, the disk drive device further comprises the peripheral interface device. Variable speed data transfer of the digital data stream from the disk drive device to the video decoder is performed via a data buffer of the peripheral interface device. The computer system according to claim 3. 5. The data transfer from the disk drive device to the data buffer of the peripheral interface device is executed at a speed substantially equal to a maximum value of a variable speed data transfer speed from the data buffer to the video decoder. The computer system according to claim 4, wherein the computer system is a computer system. 6. An audio controller connected to the system bus for controlling audio reproduction, further comprising an audio controller for receiving and reproducing audio data decoded by the audio decoder. The computer system according to claim 2. 7. The apparatus further comprises a video bus connecting between the video decoder or the sub video decoder and the display controller, wherein one of the video decoder and the sub video decoder comprises:
The computer system according to claim 1, wherein the decoded sub-picture data is combined with the decoded moving picture, and the combined video data is transferred to the display controller via the video bus. 8. The display controller combines the video data received via the video bus on the graphics to display the image on the screen.
The described computer system. 9. The audio decoder further comprises an audio bus connecting the audio decoder and the audio controller, wherein the audio decoder transfers the decoded audio data to the audio controller via the audio bus. The computer system according to claim 6. 10. The audio controller comprises a sound source unit, means for selectively reproducing the output from the sound source unit and the audio data transferred from the audio decoder via the audio bus. The computer system according to claim 9, characterized in that: 11. A computer system connectable to a disk drive device storing variable-speed-encoded moving image data, which is a peripheral interface device connected to a bus of the computer system and has a data buffer. A peripheral interface device that executes variable speed data transfer from the disk drive device to the computer system using the data buffer; and the disk drive device connected to the bus via the data buffer of the peripheral interface device. A video decoder that decodes the variable-speed-encoded moving image data transferred from the computer, and a display controller that is connected to the bus and that controls a display monitor of the computer system. A computer system, comprising: a display controller that receives the generated moving image data and displays it on the screen of the display monitor. 12. A computer system capable of connecting to a disk drive device capable of driving a recording medium on which moving picture data with sub-picture is digitally compressed and recorded, and a card slot provided in a computer main body, From a card controller that is connected to the bus of the computer system and that controls a card that is mounted in the card slot, and a card that can be mounted in the card slot and that is transferred via the card controller A card including a video decoder and a sub video decoder for respectively decoding the moving picture data and the sub video included in the digital data string, and a display controller connected to the bus and controlling a display monitor of the computer system. And a display controller for receiving a moving picture and a sub-picture decoded by the card via the card controller and displaying moving picture data with the sub-picture on the screen of the display monitor. system. 13. Digital compression encoded audio data is recorded on the recording medium by being multiplexed with the moving image data with the sub-picture, and the card is a digital data string read from the disc drive device. 13. The computer system according to claim 12, further comprising an audio decoder that decodes audio data included in. 14. The moving image data is stored in a recording medium of the disk drive device after being subjected to variable speed encoding, and the video decoder decodes the variable speed encoded data. Item 12. The computer system according to item 12. 15. A peripheral interface device having a data buffer, and using the data buffer to transfer data between the computer system and a peripheral device, the disk drive device further comprises the peripheral interface device. Variable speed data transfer of the digital data string from the disk drive device to the video decoder of the card is performed via a data buffer of the peripheral interface device. 15. The computer system according to claim 14. 16. The data transfer from the disk drive device to the data buffer of the peripheral interface device is executed at a speed substantially equal to a maximum value of a variable speed data transfer speed from the data buffer to the video decoder. The computer system according to claim 15, wherein the computer system is a computer system. 17. An audio controller connected to the system bus for controlling audio reproduction, comprising:
14. The computer system according to claim 13, further comprising: an audio controller that receives and reproduces the audio data decoded by the audio decoder. 18. A video bus connecting the card controller and the display controller is further provided, wherein the card controller is a moving image decoded by the video decoder of the card, and sub-picture data decoded by the sub-video decoder. 13. The computer system according to claim 12, wherein the composite video data is composited, and the composited video data is transferred to the display controller via the video bus. 19. The computer system according to claim 18, wherein the display controller synthesizes the video data received via the video bus on the graphics and displays it on the screen. 20. An audio bus for connecting between the card controller and the audio controller is further provided, wherein the card controller sends audio data decoded by an audio decoder of the card to the audio controller via the audio bus. 18. The computer system according to claim 17, wherein the computer system transfers. 21. The audio controller comprises a sound source unit, means for selectively reproducing output from the sound source unit and audio data transferred from the audio decoder via the audio bus. 21. The computer system according to claim 20, wherein: 22. A computer system connectable to a disk drive device storing variable-speed-encoded moving image data, wherein the peripheral interface device is connected to a bus of the computer system, and has a data buffer. A peripheral interface device that uses the data buffer to execute variable speed data transfer from the disk drive device to the computer system; a card slot provided in the computer body; and a bus connected to the computer system, A card controller for controlling a card mounted in the card slot; a card mountable in the card slot, the variable speed encoded data transferred from the disk drive device via a data buffer of the peripheral interface device; Was A card including a video decoder for decoding image data, and a display controller connected to the bus for controlling a display monitor of the computer system, wherein the video data decoded by the video decoder of the card is passed through the card controller. And a display controller for receiving and displaying on a screen of the display monitor.