JPH10145780A - Video/sound reproducing system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To deal with reproducing of various applications conformed to the MPEG(Moving Picture Experts Group) 1 and MPEG 2 standards with one type of hardware and to deal, if a new application appears, with this only with a software. SOLUTION: In a video/sound reproducing system for reproducing information composed of video data, audio data and other data, A CPU 100 separates the information into video data, audio data and other data using a software, and each separated data is placed in a system memory 120. If a transfer request is received from a processing part for processing each data, a PCI bridge 221 transfers each data from the system memory to the processing part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to MPEG (Mov).
ing Picture coding Expert
Group: an image / audio reproducing apparatus (hereinafter referred to as MP) for reproducing information including image data, audio data, and other data compressed using moving image compression / coding standards 1 and 2.
In particular, the present invention relates to a reproduction system for processing such data on a personal computer (hereinafter, referred to as a PC).

[0002]

2. Description of the Related Art First, referring to FIG.
The playback device will be outlined.

FIG. 5 shows an internal block of a PC. The PC has a CPU 100 and a CPU-PC.
The I-bridge 110 includes a dedicated bus 10 for the CPU 100,
It has a function of exchanging buses bidirectionally with a PCI bus 20 which is a kind of general-purpose bus. The system memory 120 temporarily stores programs, data, and the like, and a graphics controller (hereinafter, referred to as GDC) 140 controls screen display (that is,
Control the monitor).

A hard disk drive (HDD) 160
Records information (hereinafter referred to as multimedia data) including image data, audio data, and other data compressed according to the MPEG1 and MPEG2 standards (hereinafter collectively referred to as MPEG standards). Although not shown, there are elements for controlling the keyboard and the floppy disk.

[0005] To the MPEG reproducing apparatus 200, an NTSC monitor 170 and a speaker 180 are connected.
It decodes multimedia data transferred via the I bus 20 to restore and output images or sounds.

Referring to FIG. 6, an MPEG reproducing apparatus 200 shown in FIG.
The I-bridge 201 converts the signal supplied from the PCI bus 20 into a bus standard in the MPEG playback device, and
The bus standard in the EG playback device is converted into the standard of the PCI bus 20. The buffer memory 203 is a PCI bridge 201
Temporarily store data transferred via
It is used to transfer data in response to a data request from the MPEG video decoder 204 and the MPEG audio decoder 205.

[0007] The BEMUX 202 reads data from the buffer memory 203 in response to a transfer request from the MPEG video decoder 204 and the MPEG audio decoder 205, separates the read data into video data, audio data, and other data. Transfer to the decoder. The MPEG video decoder 204 and the MPEG audio decoder 205
The decoder decodes video data and audio data compressed according to the G standard. NTSC encoder 206 is MPEG
The image decoded by the video decoder 204 is converted from a digital signal to an analog signal, and the television (NTSC monitor) 17
It is converted to a signal that can be displayed as 0. On the other hand, DAC 207
Converts the PCM audio decoded by the MPEG audio decoder 205 into analog and outputs the analog to the speaker 180.

Referring to FIG. 5 and FIG. 6, the above-described MPEG
The order in which the playback device 200 plays back multimedia data will be described.

When a user attempts to reproduce multimedia data, the user transfers the data desired to be reproduced from the HDD 160 to the system memory 120. At this time, the data transfer method includes a software transfer in which the CPU 100 reads data from the HDD 160 byte by byte and writes the data into the system memory 120;
0 temporarily occupies the PCI bus 20 and directly
60 to the system memory 120.

[0010] The data transferred to the system memory 120 is transferred to the MPEG reproducing apparatus 200. As a data transfer method at this time, the CPU 100 reads data from the system memory 120 one byte at a time,
Software transfer to the G playback device 200 and MP
The EG playback device 200 temporarily occupies the PCI bus 20 and directly transfers the MPEG playback device 20 from the system memory 120.
There is a DMA transfer for transferring data to 0.

The data transferred to the MPEG reproducing apparatus 200 is transferred to the buffer memory 2 via the PCI bridge 201.
03. As described above, the MPEG video data 204 and the MPEG audio decoder 205
When there is a data transfer request to MUX 202, DE
The MUX 202 reads the data from the buffer memory 203, separates the data into MPEG video data, MPEG audio data, and other data, and transfers the data to the MPEG video data 204 and the MPEG audio data 205 as described above. The transferred data is decoded by each decoder, and the video is converted to an analog video signal by the NTSC encoder 206 and the audio is converted to an analog audio signal by the DAC 207 and output.

By the way, the compression according to the MPEG standard is not limited to a simple MPEG reproducing apparatus, but also to a video CD and a DV.
It is also used for various applications such as D. In these applications, extra data is stored in MPEG
Processing such as adding to the beginning or end of the data part of the standard or putting data such as graphics in parts other than video and audio data is performed. By this, basically M
The shape conforms to the PEG standard.

Here, the data structure of the main application will be described. FIG. 7 shows the data structure of MPEG1, and FIG. 8 shows the data structure of MPEG2. Usually, in MPEG video data, M
The packet portion shown in FIGS. 7 and 8 can be decoded by either PEG1 or MPEG2. Therefore, the DEMU
The X202 needs to separate the pack header and the system header shown in FIGS. As can be easily understood from FIGS. 7 and 8, regarding the pack header portion,
The data structure is different between MPEG1 and MPEG2.

FIG. 9 shows a file portion of a video (or audio) compressed in accordance with the MPEG standard in a video CD file format. MPEG-A
The V data portion is a portion compressed by MPEG1, and the other portions, that is, the pause empty, the front margin, and the rear margin are unnecessary data when reproducing actual images and sounds.

FIG. 10 shows the file format of the DVD, and the data structure is the same as the data structure of MPEG2, but the graphic data and the like have the data structure shown as (P) in FIG. Recorded in the packet part.

Further, conventionally, as an image reproducing apparatus, for example, one described in Japanese Patent Application Laid-Open No. 6-319125 is known (see FIG. 11). Data is CD-RO
When the user tries to reproduce the data, the compressed data is transferred to the MPEG decoder 5 via the CD-ROM drive.

[0017]

As is apparent from the above description, MPEG1, MPEG2, video CD, DV
If data such as D is to be reproduced, a reproduction board suitable for each data structure is prepared because each data structure is different, or the above-mentioned DEMUX 202 is provided with a function of processing a different part of each data structure. , MPEG video decoder 204 and MPEG audio decoder 2
There is a method of outputting to 05 only the common part of each data structure.

In the method of preparing individual reproduction boards, it is necessary to design the DEMUX 202 in accordance with each data structure. On the other hand, in the method of providing the DEMUX 202 with a function of processing a different part of the data structure, the DEMUX 202 is required.
There is a problem that the design of X202 becomes complicated.
In addition, in each case, whenever a new application using the MPEG standard comes out,
There is also a problem that the EMUX 202 needs to be redesigned.

In the image reproducing apparatus shown in FIG. 11, data recorded on a CD-ROM is
1. In the case of MPEG2 and video CD, MP
A part of the EG decoder 5 data processing differs. The reason for such a difference in processing is as described above,
This is because the data structure is different. Therefore, in the image reproducing apparatus shown in FIG. 11, in order to cope with all data structures, a function capable of processing different data portions is realized and implemented in the MPEG decoder 5, or an MPEG decoder capable of processing each data is provided. You need to prepare.

However, when the function of processing different data portions is realized, the circuit of the processing portion becomes complicated. On the other hand, if an MPEG decoder capable of processing each data is prepared, the introduction cost for the user is increased and the reproduction is increased. There is a problem that the board must be replaced for each application.

It is an object of the present invention to process different parts in each data structure by software and to execute M
An object of the present invention is to provide an image / sound reproduction system which can be used for applications such as PEG1, MPEG2, video CD, DVD and the like.

It is another object of the present invention to provide an image / sound reproducing system which can cope with the emergence of a new application using the MPEG2 standard only by changing / adding software.

[0023]

According to the present invention, there is provided an image / sound reproducing system used for reproducing the video data and the audio data from information including the video data and the audio data. Processing means for playing back audio data; separating means for separating the video data and the audio data using software from the information and arranging them in a system memory; and the system memory in response to a transfer request from the processing means. And a transfer means for transferring the video data data and the audio data to the processing means.

Further, according to the present invention, video data,
The video data, the audio data, and the image / audio reproduction system used when reproducing the other data from the information including the audio data and other data, wherein the video data, the audio data, and the other Processing means for reproducing the data, separating means for separating the video data, the audio data, and the other data from the information by using software, and arranging the separated data in the system memory; and a transfer request from the processing means. Accordingly, there is provided an image / sound reproducing system having a transfer means for transferring the video data data, the audio data, and the other data from the system memory to the processing means.

In the present invention, since each data is separated by software, information such as a transfer rate at the head of each data can be managed, and data with a low transfer rate is transferred by software. be able to.

According to the present invention, if one reproduction system is designed, MPEG1, MPEG2, video CD, DV
In addition to being able to run applications such as D, even if new applications using the MPEG standard appear in the future, it will be possible to respond by simply changing / adding the software of the separating means.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

Referring to FIG. 1, in the image / sound reproduction system shown in FIG. 1, the same components as those in the image / sound reproduction system shown in FIG.
Description is omitted. In the illustrated image / sound playback system,
The function of the MPEG playback device 220 is different from that of the MPEG playback device 200 shown in FIG.

As shown in FIG. 1, the MPEG playback device 22
0 is provided with a PCI bridge 221. The PCI bridge 221 is connected to the MPEG video recorder 204 and the MPE.
G audio decoder 205 and AC-3 decoder 2
09. MPEG video recorder 204
And the MPEG audio decoder 205 are NT
NTS via SC encoder 206 and DAC 207
It is connected to a C monitor (television) 170 and a speaker 180, and the AC-3 decoder 209 is connected to a speaker 190 via a DAC 210.

Referring also to FIG. 2, the PCI bridge 221 includes a master function block 301 and a slave function control unit 30.
2 and a data control unit 303. The slave function control unit 302 executes bus control when the CPU 100 accesses internal registers such as the MPEG video decoder 204 and the MPEG audio decoder 205 via the PCI bus 20. . The master functional block (DMA controller) 301 requests the CPU-PCI bridge 110 to temporarily occupy the right to use the PCI bus 20, or after acquiring the right to use the PCI bus 20,
It has a function of reading data from the system memory 120 via the bus 20 and transferring the data to the MPEG video decoder 204 or the like. The master function block 301 has a built-in DMA controller so that data can be read directly from the system memory 120 and transferred to the MPEG video decoder 204 or the like. Here, a DMA controller 301 having three independent DMA transfer channels (first to third DMA transfer channels) is shown. Then, the first DMA transfer channel is assigned to transfer of MPEG video data, and the second DMA channel is assigned to transfer of MPEG audio data.

The first, second, and third DMA transfer channels are respectively DMA address counters 311, 313,
315 and DMA byte counters 312, 314, and 316. Each DMA address counter is incremented by one each time one byte is transferred, and the transfer address is indicated by each DMA address counter. Each DMA
The transfer byte counter is decremented by one each time one byte is transferred,
Each DMA transfer byte counter indicates the number of data to be transferred.

If the user selects MPEG1 or MPEG2
When attempting to reproduce the data of
The G video decoder 204, the MPEG audio decoder 205, the NTSC encoder 206, and the DAC 207 are initialized to decode the transferred data,
It is ready to output video to 0 and audio to speaker 180.

Thereafter, the CPU 100 reads from the HDD 160 the data that the user intends to reproduce. When reading the data, the CPU 100 reads the data structure of MPEG1 shown in FIG. 7 or MPEG2 shown in FIG.
MPEG data 401, MP
The EG audio data 402 is extracted and placed on the system memory 120 as shown in FIG.

Referring to FIG. 3, MPEG video data 401, MPEG audio data 402 and the like are arranged on system memory 120. That is, the MPEG video data 401 is stored in the address B1 on the system memory 120.
Therefore, the MPEG audio data 402 has the address B
Arranged from 2.

Referring again to FIGS. 1 and 2, when the extraction of the data and the arrangement of the extracted data in the system memory 120 are completed, the CPU 100 sends the parameters for executing the transfer to the DMA controller in the PCI bridge 201. Set. That is, in order to transfer the MPEG video data, the CPU 100 stores the MPEG address in the system memory 120 in the DMA address counter 311.
Set the address B1 where the video data is located,
The number of MPEG video data (here, the value of B2-B1) is set in the DMA byte counter 312.

Next, in order to transfer the MPEG audio data, the CPU 100 sets an address B2 in the system memory 120 where the MPEG audio data is located in the DMA address counter 313,
The number of MPEG audio data (here, the value of B3-B2) is set in the DMA byte counter 314. In order to start reproduction, the CPU 100 sends an MPEG video decoder 204 and an MPEG audio decoder 205
Set the playback start command to.

Both decoders to which the playback command is set,
Video data transfer request 3 to DMA controller
1. An audio data transfer request 33 is output. Upon receiving the transfer request, the DMA controller starts reading data in the system memory 120. The DMA controller that has read the data outputs a response to each data transfer request and transfers the data to each decoder.

When the value of the DMA byte counter becomes "0", the DMA controller notifies the CPU 100 of the fact. As a result, the CPU 100 confirms that the transfer has been completed. When the transfer is completed, the CPU 100
Reads the next reproduction data from the HDD 160 and executes the same processing as described above. By repeating the above processing, the compressed data of MPEG1 and MPEG2 that the user intends to reproduce is reproduced.

In the above description, the parameters for transferring the MPEG video are set in the DMA controller first, but the operation is the same even if the MPEG audio is processed first. The operation is the same even when the data that the user is trying to reproduce is only MPEG video or only MPEG audio. simply,
DMA address counter corresponding to non-existent data,
There is no setting process for the DMA byte counter.

Next, referring to FIG. 1 and FIG.
The operation at the time of reproducing D will be described. In this case, the above-described HDD 160 is replaced with a CD-ROM drive. That is, from the viewpoint of the CPU 100, the HD
Both D and CR-ROM drives are recording devices. The difference is that HDDs can write and read,
The point is that the D-ROM drive is only for reading.

When a user attempts to reproduce an image recorded on a video CD, the CPU 100
The data recorded on the video CD is read from the drive. At this time, as shown in FIG. 5, data irrelevant to video or audio reproduction added before and after the video or audio data compressed according to the MPEG1 standard is removed.

Further, the above-described MPEG1, MPEG2
As in the case of the reproduction of the above, MPEG video data and MPEG audio data are extracted from the video CD data from which the irrelevant data has been removed, and are arranged on the system memory 120. The processing flow after this is MPEG1, MPEG2
Since this is the same as the case where the data is reproduced, the description is omitted here.

Referring to FIG. 1 and FIG. 2, the operation at the time of reproducing a DVD will be described. In this case, the above-described HDD 160T is replaced with a DVD drive. That is, from the viewpoint of the CPU 100, both the HDD and the DVD drive are recording devices. The difference is that the HDD can perform writing and reading, but the DVD drive can only read.

When a user attempts to reproduce data recorded on a DVD, the CPU 100 reads data recorded on a DVD disk from a DVD drive. At this time, in addition to the video data or audio data compressed according to the MPEG standard as shown in FIG.
Extracts audio data compressed by the AC-3 standard, which has higher sound quality than audio compressed by the MPEG standard, specified by the VD standard, or bitmap data for creating a menu screen for simplifying user operations .
The extracted data is arranged in the system memory 120 as shown in FIG.

CPU 100 is a DMA controller 301
The first DMA channel is for transferring MPEG video data, the second DMA channel is for transferring MPEG audio data, and the third DMA channel is for AC-3.
Assign each for data transfer.

As described above, data is stored in the system memory 1.
After being placed on the CPU 20, the CPU 10
0 sets a reproduction command in each decoder. As a result, each decoder sends a data transfer request. In response to the transfer request, the DMA controller
20, necessary data is transferred to the decoder. As a result, video or audio is reproduced and output. On the other hand, the bitmap data for creating the menu screen is GDC1
The data is transferred to the display unit 40 and is displayed in a graphic form, and is superimposed on the video output, thereby obtaining a display as intended by the application creator.

FIG. 4 shows another example of the PCI bridge used in the image / sound reproducing system according to the present invention. Referring to FIG. 4, the illustrated PCI bridge 221 is an example in which the DMA controller 301 has only one DMA channel. In this case, it is necessary to transfer the data by the DMA controller and the software by the CPU 100.

Generally, when comparing the video data amount and the audio data amount, the video data amount is much larger. Therefore, the transfer of the video data is executed by the DMA controller, and the transfer of the audio data is executed by the software of the CPU.

Referring to FIGS. 1 and 4, MPEG1, M
The operation when reproducing PEG2 data will be described.

The process up to the process of arranging data from the HDD 160 to the system memory 120 is the same as the example described with reference to FIGS. 1 and 2, and a description thereof will be omitted. At the time when each data has been arranged on the system memory 120, C
The PU 100 sets the start address B1 of the MPEG video data in the DMA address counter 311 in the DMA controller 301, and sets the number of data to be transferred (here, the value of B2-B1) to the DMA byte counter 312,
A playback command is set in the PEG video decoder 204 and the MPEG audio decoder 205.

As described above, the DMA controller 301 reads MPEG video data from the system memory 120 and transfers it to the MPEG video decoder 204. The MPEG video decoder 204 decodes the data and reproduces an image. On the other hand, in the case of MPEG audio, the CPU 100 monitors a data transfer request from the MPEG audio 203, and executes a process of transferring data when a request comes.

As a result, both video and audio are reproduced. That is, it is possible to reproduce MPEG video and MPEG audio without using a high-performance PCI bridge.

The operation of reproducing a video CD is clear from the description with reference to FIGS. In other words, in FIG.
Although the transfer is performed by the MA controller, in this example, the transfer may be performed by software of the CPU. Also, DV
When reproducing D, the description can be made in the same way as when reproducing a video CD.

[0054]

As described above, according to the present invention, data up to the basic part is separated by software, so that hardware only needs to be able to process the data of this basic part. Therefore, there is no need to design hardware corresponding to each application, and the burden of hardware design can be reduced.

Further, even when a new application adopting the MPEG standard comes out, the basic part is not changed in order to maintain compatibility with the past application. There is an effect that the design of the wear becomes unnecessary.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an example of an image / sound reproduction system according to the present invention.

FIG. 2 is a block diagram showing an example of a PCI bridge shown in FIG.

FIG. 3 is a diagram showing an arrangement of data in a system memory.

FIG. 4 is a block diagram showing another example of the PCI bridge shown in FIG. 1;

FIG. 5 is a block diagram showing an example of a conventional image / sound reproduction system.

6 is a block diagram of the MPEG playback device shown in FIG.

FIG. 7 is a diagram showing a data structure in MPEG1.

FIG. 8 is a diagram showing a data structure in MPEG2.

FIG. 9 is a diagram showing a data structure in the video CD standard.

FIG. 10 is a diagram showing a data structure in the DVD standard.

FIG. 11 is a block diagram showing another example of a conventional image / sound reproduction system.

[Explanation of symbols]

 Reference Signs List 100 CPU 110 CPU-PCI bridge 120 System memory 140 Graphics controller 150 PC monitor 160 Hard disk drive 170 NTSC monitor (television) 180, 190 Speaker 220 MPEG playback device

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI H03M 7/30 H03M 7/30 Z H04N 5/765 H04N 5/781 510G 5/781 5/92 H 5/92

Claims (12)

[Claims] 1. An image / sound reproduction system used when reproducing the video data and the audio data from information including video data and audio data, a processing unit for reproducing the video data and the audio data, Separating means for separating the video data and the audio data using software from the information and arranging the video data and the audio data in a system memory, and converting the video data data and the audio data from the system memory in response to a transfer request from the processing means An image / sound reproduction system comprising: a transfer unit for transferring the data to the processing unit. 2. The image / audio reproduction system according to claim 1, wherein said information is compressed according to the MPEG standard. 3. The image / audio reproduction system according to claim 2, wherein said information is recorded on a hard disk. 4. The video / audio reproduction system according to claim 2, wherein said information is recorded on a video CD. 5. The image / sound reproducing system according to claim 1, wherein a parameter indicating a position of the video data data and the audio data on the system memory is set from the separation unit to the transfer unit. Wherein the transfer means transfers the video data data and the audio data in accordance with the parameters. 6. The image / sound reproduction system according to claim 1, wherein said transfer means transfers the video data data and the audio data by DMA transfer. system. 7. The image / sound reproducing system according to claim 1, wherein said transfer means performs a DMA transfer.
An image / audio reproduction system, comprising an A transfer unit, wherein the DMA transfer unit transfers data having a higher transfer rate among the video data data and the audio data. 8. The image / sound reproduction system according to claim 7, wherein data of a lower transfer rate among the video data and the audio data is transferred using software. Reproduction system. 9. An image / sound reproducing system used when reproducing the video data, the audio data, and the other data from information including video data, audio data, and other data, wherein the video data, Processing means for playing back the audio data and the other data, separating means for separating the video data, the audio data, and the other data from the information by using software, and arranging them in a system memory; Transfer means for transferring the video data data, the audio data, and the other data from the system memory to the processing means in response to a transfer request from the processing means. 10. The image / sound reproduction system according to claim 9, wherein said information is recorded on a DVD, and said video data and said audio data are MP
An image / sound reproducing system characterized by being compressed according to the EG standard and the other data is data compressed according to the DVD standard. 11. The image / audio reproduction system according to claim 9, wherein said transfer means transfers said video data data, said audio data, and said other data by DMA transfer. Image / audio playback system. 12. The image / sound reproduction system according to claim 1, wherein said transfer means performs a DMA transfer.
An image / audio data transfer device, wherein an MA transfer unit is provided, and the DMA transfer unit transfers only data having a high transfer rate among the video data data, the audio data, and the other data. Reproduction system.