JP2001057026A - Reproducer and reproducing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make musical data suitable for being preserved in a computer to be directly reproduced as they are. SOLUTION: A system controller 17 analyzes the file structure and the file contents of the data recorded on an optical disk 1 and judges whether the data are a musical file or not based on the analyzed result and the file extension or the file header of the data and when the data are judged to be a musical file, the controller converts the musical file into a musical signal by a D/A converter 8 or the like based on the analyzed result and reproduces the musical data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CD player and a CD-RO for reproducing music data on a CD-ROM.
The present invention relates to a reproducing apparatus such as an M apparatus, a CD-R apparatus, and a CD-RW apparatus and a reproducing method thereof.

[0002]

2. Description of the Related Art The CD standard originating from the music CD standard is very complicated, covering a wide variety of recording formats and media types, but is broadly divided into music applications and computer applications.

For the former use, a reproducing device called a CD player is mainly used, and for the latter use, a reproducing device called a CD-ROM drive is mainly used, but usually both devices have a reproducing function of a CD-DA disk.

However, there is no function of reproducing music data recorded as computer data, and music data is generally reproduced on a sound source board of a host computer.

In view of the above, conventional techniques for recording and reproducing music data in the CD-ROM format and for compressing and expanding the music data (for example,
Japanese Patent Application Laid-Open No. Hei 9-185868) has been proposed, but it is not configured to interpret and reproduce the most important file system for sharing data with a computer.

A further description will be given. C for music playback
The standard of D-DA is Red Book (RED BOOK),
CD-R for computer data storage
The OM standard is the Yellow Book (YELLOW BOO)
K).

The CD-ROM standard incorporates a sector structure enabling random access based on the CD-DA standard and a powerful error correction function.

[0008] However, DA is a data format that is difficult to handle for a computer due to the main feature of sequential read, rough random access, and an insufficient error rate for computer data.

[0009] Generally, a CD is called multimedia. With the moderate storage capacity of CDs, the ease of duplication, and the advancement of standards and data compression technology that have been sequentially established, a single medium can handle a variety of information such as text, music, and video. This is because the information is recorded in digital data that can be easily used by a computer.

At present, the performance of personal computers is sufficient to handle multimedia, and even a basic personal computer performs one task such as music composition, editing, mixing, and effects.
Individuals can easily be made with one machine.

In addition, since the cost of a recordable CD drive has become low, music data of a song created by the user is
Recording on the DR and listening to it on a CD player is also actively performed.

In order to listen to music data created by a computer with a general CD player, a CD-D
You need to create an A format CD. But,
Since the CD-DA format is not suitable for storing computer data, music data is usually stored separately in a CD-ROM format or another storage device.

[0013]

However, if music data is separately stored in a CD-ROM format or another storage device as described above, the
-DA data is 1 sampled at 44.1 KHZ
Since it is 6-bit stereo data and the data amount is about 10 MB in one minute, there is a problem that it is extremely irrational to handle data for reproduction and data for storage separately.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its first object to enable a computer to directly reproduce music data suitable for storage as it is.

Next, a music file that is typically handled by a typical OS of a personal computer is a WAVE file. A WAVE file has a simple structure in which an information header such as the number of channels, a sampling rate, and the number of quantization bits is added to PCM data.
Data converted into a WAVE file can be easily reproduced by a D / A converter.

No special processing is required to reproduce this type of file, but as described above, a WAVE file has a data amount of about 10 MB in one minute, and a CD-RO
The M format has a disadvantage that data can be recorded only for about 65 minutes.

At present, data distribution is indispensable for music distribution over networks such as the Internet. With the improvement of computer processing capacity, various types of data can be compressed and decompressed by software.
Motivation to save or distribute music data as a file is increasing very much.

For example, MP3 which is highly evaluated for its sound quality and compression ratio
(MPEG1 AUDIO LAYER III) CD
Since data can be reduced to about 1/10 while maintaining sound quality close to DA, more than 150 ordinary music can be stored in a CD-ROM format on one CD. Therefore,
A second object of the present invention is to enable a computer to directly reproduce compressed music data suitable for storage.
The purpose of.

Next, although the dramatic increase in the processing capacity of personal computers in recent years seems to be well known, the same holds true for the processing capacity of an embedded computer chip, that is, a system controller.

Conventionally, dedicated hardware has been required for decompressing compressed data, but decompression by software has become possible by improving the processing capability of the system controller. Also, considering a plurality of existing compression formats and new compression formats that will appear in the future, the time and cost will increase if hardware is used.

Accordingly, a third object of the present invention is to enable compressed music data suitable for storage by a computer to be reproduced as software using a system controller.

Next, in order to reproduce a music file, it is necessary to know in advance where the music file is located. In the case of a CD-DA, the start position and the time of a song can be known by reading the TOC area on the disc. However, in the case of a music file on a CD-ROM, since there is no such information, the file is searched for. Must be obtained from directory information.

However, file search takes time when files are scattered in subdirectories or when the number of files is large, and the usability is impaired. In addition, if the song name or album name is substituted for the file name or directory name, it may be inconvenient because it may be difficult to change it later.

Therefore, a fourth object of the present invention is to improve the operability at the time of reproducing a music file by reading a TOC file used for configuring and managing the music file.

Next, although the performance of the computer has been improved, high-performance and heavy-load applications have also appeared at the same time, so there is no better way to play music without imposing a load on the CPU.

Generally, a CD-ROM drive is a CD-D
A can be played, but a music file cannot be played regardless of whether it is compressed. The fact that the computer reads the music file and transfers the data to the sound source board is not trivial in terms of processing, but the amount of data is large, so that the CPU load increases not less and the parallel operation with the application is performed. If so, the risks in terms of stability will increase.

Therefore, a fifth object of the present invention is to enable a music file to be directly reproduced by an instruction from a host computer.

[0028]

In order to achieve the first object, the present invention provides a means for analyzing a file structure and file contents of data recorded on a recording medium, a result of analysis by the means, Means for determining whether or not the music file is a music file based on a file extension or a file header of data; and when the means determines that the music file is a music file, the music file is converted to a music signal based on the analysis result and reproduced. Provided is a reproducing apparatus provided with music reproducing means.

Also, in order to achieve the second object,
Means for determining the compression type of the music file based on the file extension or file header of the data, and means for expanding the music file based on the compression type determined by the means; Should be provided.

Further, in order to achieve the third object, in the above-described reproducing apparatus, it is preferable that the decompression means is provided in a system control means for controlling the whole of the reproducing apparatus.

Also, in order to achieve the fourth object,
In the reproducing apparatus as described above, means for reading and acquiring a text file describing information such as a recording address, a song time, a file format, an album name, a song name, and an artist name of a music file recorded on the recording medium is provided. It is good to provide.

Further, in order to achieve the fifth object, in the above-described reproducing apparatus, means for connecting a host computer, and the music file based on an instruction from the host computer connected by the means. It is preferable to provide a means for executing reproduction.

Also, the file structure and file contents of the data recorded on the recording medium are analyzed, and it is determined whether or not the file is a music file based on the analysis result and the file extension or file header of the data. If it is determined that the music file has been analyzed, the music file is converted into a music signal based on the analysis result and the music signal is played back.

Further, in the reproducing method as described above,
The compression type of the music file may be determined based on a file extension or a file header of the data, and the music file may be expanded based on the determined compression type.

Further, in the above-described reproducing method, a text file describing information such as a recording address, a song time, a file format, an album name, a song name, and an artist name of a music file recorded on the recording medium is stored. It is good to read and get.

[0036]

Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a block diagram showing a configuration of an optical disk reproducing apparatus according to one embodiment of the present invention.

This optical disk reproducing apparatus includes an optical disk 1
Is rotationally driven by the spindle motor 2. The spindle motor 2 is controlled by the motor driver 3 and the servo processing unit 4 so that the linear velocity or the angular velocity becomes constant.
The linear velocity or the angular velocity can be changed stepwise.

The pickup 5 incorporates a semiconductor laser light source (not shown), an optical system, a focus actuator, a track actuator, a light receiving element, and a position sensor, and has a function of irradiating the optical disk 1 with laser light and reading data. Have.

The pickup 5 can be moved in the sledge direction by a seek motor (not shown). The focus actuator, the track actuator, and the seek motor are controlled by the motor driver 3 and the servo processing unit 4 based on signals obtained from the light receiving element and the position sensor so that the laser spot is located at a target location.

The reproduction signal obtained by the pickup 5 is amplified by the read amplifier 6 and binarized, and then input to the CD decoder 7 to undergo deinterleaving and error correction. At this time, the data for which the error correction has not been completed is complemented.

In the case of a CD-DA, the data is input to a D / A converter 8, amplified by an amplifier 14, and output to a line-out terminal 15 or a speaker 16 to reproduce music. Further, it is also possible to pass data through the CD-ROM decoder 9 and temporarily store the data in the memory 10 before inputting the data to the D / A converter 8, which is effective in preventing noise interruption when the servo is deviated due to vibration.

On the other hand, in the case of a CD-ROM,
-Input to the ROM decoder 9 and subjected to error correction processing for further improving data reliability. The system controller 17 controls whether to store the data in the memory 10 as it is or to store the data in the memory 10 after performing the data expansion processing by the data expansion processing unit 11.

The memory manager 12 controls data access to the memory 10 and can process data transfer to each unit in parallel. With this function, the data in the memory 10 can be sent to the D / A converter 8 or the host interface (I / F) 13 while reading the data from the optical disc 1 into the memory 10.

The host interface 13 has an SCS
I, ATAPI, USB, 1394, etc., for connecting a host computer. The D / A converter 8 can adjust the conversion rate according to the sampling rate.

The system controller 17 controls the above-described units, and can read arbitrary sector data and store it in the memory 10. The system controller 17 can freely access the memory 10 to analyze the sector data and to store the data in the memory 10. On the other hand, it is also possible to expand the data in the memory 10 by performing a decompression process.

That is, the system controller 17
For analyzing the file structure and file content of the data recorded on the recording medium, and determining whether or not the file is a music file based on the analysis result by the means and the file extension or file header of the data. Means, and when the music file is determined by the means,
It functions as a music playback unit that converts the music file into a music signal and plays it based on the analysis result.

The function of the means for determining the compression type of the music file based on the file extension or the file header of the data and the means for expanding the music file based on the compression type determined by the means are provided. Fulfill.

Further, it functions as a means for reading and acquiring a text file describing information such as a recording address, a song time, a file format, an album name, a song name, and an artist name of a music file recorded on the recording medium. .

Further, the function of a means for connecting a host computer and a means for executing the reproduction of the music file based on an instruction from the host computer connected by the means is achieved.

The optical disk reproducing apparatus of this embodiment has a great feature in interpreting a file system of an optical disk (for example, a CD-ROM), and the standard file system is ISO9660.

FIG. 2 is an explanatory diagram showing the configuration of a file system based on ISO9660. In ISO9660, a logical block number (LOGICAL BLOCK) is used.
NUMBER: LBN (First Volume Descriptor (PRIMARY VOLUME DESCRI) in 16 sectors)
PTER: PVD).

LBN is a sector on a medium such as an optical disk (in CD-ROM, MINUTE: second (S
ECOND): a method for sequentially addressing frames (addressed by FRAME), and is a method for addressing CD-R
It is used not only for OM but also for media such as HDD and MO.

In a CD-ROM, LBN = 0 is set to 00: 0.
2:00 (2 seconds 00).
LBN is a logical sector number (LOGICAL SECT).
ER NUMBER: LSN) or logical block address (LOGICAL BLOCK ADDRESS)
S: LBA).

According to ISO9660, a method of sequentially searching for a target file position from a root directory indicated by a PVD and a path table (PATH TABLE) are described.
There is a way to point at once from E).

The method of sequentially following the root directory is similar to the FAT file of MS-DOS. However, since many seeks occur during the following process, a large overhead generally occurs in a CD-ROM drive whose seek time is not so fast.

Therefore, it is common to place pointers to all directories and files in the optical disk in a static area called a path table and directly search therefrom. The location of the path table is also pointed from the PVD.

The optical disk reproducing apparatus of this embodiment interprets the file structure in order to reproduce a music file, and needs to extract music data and, in the case of compressed data, decompression processing.

A typical one of the uncompressed music files is a WAVE file, and a typical one of the compressed music files is an MPEG1 / AUDIO file. These structures are shown in FIGS. 3 and 4. .

As shown in FIG. 3, the WAVE file is
The configuration is such that a header of 44 bytes is arranged at the head of the music data. The header records the sampling rate, the number of quantization bits, and the music data size. If the D / A converter 8 is set based on this information, the music can be reproduced simply by sending the music data as it is. . “WAV” is generally used as an extension of the file name of this file.

On the other hand, the MPEG1 / AUDIO file is composed of a plurality of frames shown in FIG. 4 and information of 128 bytes called an ID3 tag. Information necessary for decompression such as a sampling rate and a bit rate is recorded in the frame header.

MPEG1 AUDIO LAYER III
In the case of a file, the extension of the file name is generally "M
P3 "is used. The existence of the file can be confirmed from the directory information by using the extension of these files. This MPEG1 AUDIO LAYE
System controller 17 decompresses R III file
May be executed.

If the file name is a song name and the directory name is an album name, the table of contents information (T
Information that does not exist in OC) can also be obtained. But,
Unless the music file type is fixed, only the music time that is important as the music information cannot be calculated from the file size, and cannot be known unless the file is read. In other words, if the number of songs is large, the search takes a very long time.

Therefore, in the optical disk reproducing apparatus of this embodiment, the above-mentioned search is made unnecessary by reading out the TOC file in which the music information is compiled in advance. This T
The OC file is a specific text file existing in the root directory, and its structure is shown in FIG.

The contents of the TOC file are roughly divided into album information and track information, and numbers are assigned for each of them. The configuration example of FIG. 5 shows a case where the album is composed of three and the track is composed of fifteen. The album information includes an album name, an artist name, and a belonging track, and a track number is specified for the belonging track.

A plurality of track numbers can be designated by a hyphen "-" and a comma ",". The track information includes a recording address, a song time, a file format type, a song name, and an artist name. Since the address is the logical address of the CD-ROM in which the music file is recorded, the music file can be directly accessed only with the TOC file.

FIG. 6 is a flowchart showing a process of acquiring and reproducing music information on an optical disk in the optical disk reproducing apparatus. In this processing, it is determined whether or not an optical disk has been inserted in step (indicated by "S" in the figure) 1, and if it is detected that an optical disk has been inserted, the process proceeds to step 2 to perform mounting processing. In this mounting process, the TOC area of the optical disc 1 is read, and the mode and length (time) of the track are obtained. By this mounting process, it is possible to determine whether the optical disk is a CD-DA or a CD-ROM.

Proceeding to step 3, the optical disk is CD-D
It is determined whether the disc is an A disc or not. If the disc is a CD-DA disc, the process proceeds to step 8 and waits for a reproduction command.
If it is a ROM, go to step 4 to read the directory, go to step 5 and set TO to the root directory.
It is determined whether a C file exists.

If there is no TOC file in the determination at step 5, the process proceeds to step 6 to search for music files including subdirectories based on the file name extension, and proceeds to step 7 to search for the detected music file. Access and get song time. TOC is determined in step 5
If there is a file, the process proceeds to step 10 to read the TOC file to acquire music information, and then proceeds to step 8.

In step 8, it is determined whether or not there is a reproduction command.
If there is a reproduction command, the process proceeds to step 9 to execute a reproduction process. The reproduction command is given by a switch on the operation unit or by a command from the host computer.
Then, when a playback command is issued, the file of the song whose playback is instructed is read, the type of the file is determined, and if the file is a compressed file, the file is appropriately expanded, the playback rate is set, and the data is transferred to the D / A converter 8. To play music files.

In this way, the optical disk reproducing apparatus can reproduce the music file as it is, so that it is not necessary to create two CDs for reproduction and storage, and to immediately reproduce the music stored in the computer. Can be.
In addition, the compressed music file can record 100 songs or more and 600 minutes or more songs on one CD, so that it is very suitable for storing music and can directly reproduce the optical disc.

Further, the hardware cost required for the decompression processing can be reduced, and more decompression procedures can be handled in a short period of time. In addition, song information can be obtained at a high speed, so that album management and song name change become easy. Further, information that is not included in the CD-DA, such as a song title and lyrics, can be associated with the song.

The music file can be reproduced without imposing a load on the CPU of the host computer, and the host interface can be adapted to a recording and reproducing apparatus such as a CD-R drive.

[0073]

As described above, according to the reproducing apparatus of the present invention and the reproducing method of the present invention, music data suitable for storage can be directly reproduced by a computer.

According to the reproducing apparatus of the present invention and the reproducing method of the present invention, it is possible to directly reproduce compressed music data suitable for storage by a computer.

Further, according to the reproducing apparatus of the third aspect of the present invention, compressed music data suitable for storage by a computer can be reproduced by software using a system controller.

According to the reproducing apparatus of the fourth aspect and the reproducing method of the eighth aspect of the present invention, the operation at the time of reproducing the music file is performed by reading the TOC file used for the composition and management of the music file. Performance can be improved.

Further, according to the reproducing apparatus of the fifth aspect of the present invention, a music file can be directly reproduced by an instruction from the host computer.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an optical disk reproducing device according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a configuration of a file system based on ISO9660 on an optical disk to be reproduced by the optical disk reproducing device shown in FIG.

FIG. 3 is an explanatory diagram showing a configuration of a WAVE file on an optical disc reproduced by the optical disc reproducing device shown in FIG. 1;

FIG. 4 is an explanatory diagram showing a configuration of an MPEG1 / AUDIO file on an optical disc reproduced by the optical disc reproducing device shown in FIG. 1;

FIG. 5 is an explanatory diagram showing a configuration of a TOC file on an optical disc reproduced by the optical disc reproducing device shown in FIG. 1;

FIG. 6 is a flowchart showing a process of acquiring and reproducing music information on an optical disk in the optical disk reproducing device shown in FIG. 1;

[Explanation of symbols]

 1: optical disk 2: spindle motor 3: motor driver 4: servo processing unit 5: pickup 6: read amplifier 7: CD decoder 8: D / A converter 9: CD-ROM decoder 10: memory 11: data expansion processing unit 12: Memory manager 13: Host interface (I / F) 14: Amplifier 15: Line-out terminal 16: Speaker 17: System controller L: Laser light

Claims (8)

[Claims] 1. A means for analyzing a file structure and file contents of data recorded on a recording medium, and determining whether or not the data is a music file based on a result of the analysis by the means and a file extension or a file header of the data. And a music reproducing means for converting the music file into a music signal based on the analysis result and reproducing the music signal when the music file is determined to be a music file by the means. 2. The playback device according to claim 1, wherein a determination unit determines a compression type of the music file based on a file extension or a file header of the data.
A reproducing apparatus, comprising: means for expanding the music file based on the compression type determined by the means. 3. The reproducing apparatus according to claim 2, wherein said decompressing means is provided in system control means for controlling the whole of said reproducing apparatus. 4. The reproducing apparatus according to claim 1, wherein a recording address, a music time, a file format, an album name, a music name, an artist name, and the like of the music file recorded on the recording medium. A means for reading and acquiring a text file in which the information is described. 5. The reproducing apparatus according to claim 1, wherein the music file is reproduced based on an instruction from a host computer connected to the host computer and an instruction from the host computer connected by the means. A playback device comprising means for executing. 6. Analyzing the file structure and file contents of data recorded on a recording medium, determining whether the file is a music file based on the analysis result and the file extension or file header of the data, Wherein the music file is converted into a music signal and played based on the analysis result. 7. The reproduction method according to claim 6, wherein a compression type of the music file is determined based on a file extension or a file header of the data, and the music file is decompressed based on the determined compression type. A reproducing method characterized by: 8. The reproduction method according to claim 6, wherein a text describing information such as a recording address, a music time, a file format, an album name, a music name, and an artist name of a music file recorded on the recording medium. A reproducing method characterized by reading and acquiring a file.