JPH09223367A - Disk reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a reproduced video or sound from being intermittent by a retrial operation for reproduced data. SOLUTION: The decoding result of a decoding circuit 34 is given to a video/ sound data judging section 37. In the video/sound judging section 37, judgement is made as to whether reproduced data is video data or sound data based on a decoding result. In an error influence judging section 36, judgement is made as to influence to be given to restored video/sound based on a correction impossible flag when reproduced data containing error data is used. In a CPU 35, for video/sound data, if influence is small, no retrial operation is performed even when a correction-impossible error is generated. Thus, the restored video/ sound is prevented from being intermittent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disc reproducing apparatus suitable for reproducing a disc on which data is required to be read within a fixed time.

[0002]

2. Description of the Related Art Conventionally, as storage media for digital data, there are FD (floppy disk) and HD (hard disk) which are excellent in random access. In recent years, large-capacity CD-ROM and MO (magneto-optical disk)
Optical discs such as those have been adopted. Furthermore, at present, SD (Super Density Distri
k), SD-ROM and DVD (Digital Video Disk)
Etc. are being standardized.

FIG. 5 shows a disk 1 of HD, FD, MO or the like. As shown in FIG. 5, a guide groove (track) 2 is concentrically formed on the disk surface of the disk 1. FIG. 5 shows a recording format according to the constant angular velocity method, in which the track 2 is divided in the circumferential direction to form the sector 3. Further, FIG. 6 shows an optical disc 4 such as an SD. As shown in FIG. 6, tracks 5 are spirally formed on the disk surface of the optical disk 4.

A magnetic head (not shown) or an optical head (pickup) traces the disk surface along the tracks 2 and 5 to reproduce the recorded data.

When these discs are reproduced on a computer or the like, a disc drive device may be instructed to perform a retry operation in order to remove a data error. That is, when an error that cannot be corrected even by the error correction by the error correction circuit occurs in the reproduced data, the reproduction of the disk is repeated until the correct data or the error correctable data is reproduced. If the correctable data cannot be read out even after the retry operation is performed a predetermined number of times, for example, a read error message is displayed on the display and the like.
Data retry ends.

FIG. 7 is a block diagram showing a conventional disc reproducing apparatus which performs such a retry operation.

The head 21 traces the disk surface, reproduces the data recorded on the disk 20, and supplies a reproduction signal to the RF circuit 22. The RF circuit 22 has a preamplifier, an equalizer, a comparator, etc., which are not shown,
The reproduced signal is amplified and waveform equalized, then converted into a digital signal and output to an error correction circuit (hereinafter referred to as an ECC circuit) 23.

The reproduced data is error-corrected in the ECC circuit 23 and then supplied to the decoding circuit 24. Decoding circuit
Reference numeral 24 decodes the reproduction data by an inverse process of the encoding process applied to the reproduction data and outputs it. For example, if the reproduction data is MPEG (Movig Picture Experts Gr
oup) If the video data is encoded by the standard, the reproduction data is expanded according to the MPEG standard. If the reproduced data is audio data that has been subjected to Dolby AC3 compression processing specified by Dolby Corporation in the United States, AC3 decoding processing is performed on the reproduced data. Similarly, even when the reproduction data is character data such as subtitles or bitmap data, the decoding process according to the encoding process performed on the reproduction data is performed. The output of the decoding circuit 24 is output to a display circuit, an output circuit, or the like (not shown).

On the other hand, since there are many errors in the reproduced data, the ECC
In the error correction processing of the circuit 23 as well, when error-correctable data occurs, the ECC circuit 23 outputs an uncorrectable flag to the CPU 25. The CPU 25 instructs the head 21 to perform a retry operation, and replays a portion where normal data could not be obtained.

In this way, the CPU 25 repeats the retry operation until the error-correctable data is obtained. When the error-correctable data is not obtained even after the retry operation of the predetermined number of times, the CPU 25 interrupts the retry operation and displays an error message indicating that a read error has occurred on a console screen or the like not shown. In addition,
If correct data can be restored from the reproduced data by the ECC circuit 23, the retry operation is not performed.

Such a retry operation is likely to occur frequently when the disc surface is dirty, when the disc is old, or when the disc surface is scratched. In these cases, errors in reproduced data increase and error correction is often impossible, and a relatively large number of retry operations may be performed.

Various data such as various program files, numerical files of spreadsheet software such as money, text files created by a word processor or editor, video files of still images, etc. can be considered as data to be recorded on the disc. To be The retry operation allows accurate restoration of these files.

However, a video file such as a moving image, a PCM (Pulse-Code Modulation) processed audio data file, or the like may be recorded on the disc. In this case, if the number of retry operations increases, it takes a long time to read the reproduction data necessary for video output, audio output, or the like. That is, real-time reproduction may not be possible due to the limitation of the reproduction bit rate of the disc. For this reason, the restored moving image or sound may be interrupted, and in the worst case,
It may become impossible to reproduce.

[0014]

As described above, in the above-mentioned conventional disc reproducing apparatus, the quality of the restored moving image and audio may be deteriorated by the retry operation, and the reproduction cannot be performed. There was a problem that it might become.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a disc reproducing apparatus capable of restoring normal data even when a retry operation is performed. .

[0016]

DISCLOSURE OF THE INVENTION A disk reproducing apparatus according to the present invention comprises a reproducing means for reproducing information recorded on a disk medium to obtain reproduced data, and a read-out of the reproduced data within a predetermined time. Data type determination means for determining whether or not the data needs to be completed, and when error data that cannot be error-corrected occurs in the reproduction data, the processing quality of a predetermined process using the reproduction data is improved. A degree of influence determining unit that determines the degree of influence of the error data, and a control that determines whether or not to instruct the reproducing unit to perform a retry operation based on the output of the data type determining unit and the output of the influence degree determining unit. And means.

In the present invention, the data type determination means determines whether or not the reproduction data is data such as video data or audio data that needs to be read out within a fixed time. Further, the influence degree determining means determines the degree of influence of the error data on the predetermined processing quality using the reproduction data including the error data. The control means
When the error data has a relatively small influence on the predetermined processing quality for data that needs to be read out within a certain time, the reproducing unit is not instructed to perform the retry operation. As a result, it is possible to prevent the processing quality of the predetermined processing for the data that needs to be completed to be read out within the fixed time from being deteriorated by the retry operation.

[0018]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a disc reproducing apparatus according to the present invention.

The disk 30 is a magnetic disk such as FD, HD or SD or an optical disk. The head 31 is a head such as a magnetic head or an optical head (pickup),
It is provided at a position facing the disc 30, and traces the recording surface of the disc 30 to reproduce the data recorded on the disc 30.

The reproduction signal from the head 31 is supplied to the RF circuit 32. The RF circuit 32 has a preamplifier, an equalizer, a comparator, etc., which are not shown, and amplifies the reproduction signal to equalize the waveform and then converts it into a digital signal to output the reproduction data to the ECC circuit 33. The ECC circuit 33 uses the error correction code included in the reproduced data to error-correct the reproduced data. The ECC circuit 33 is adapted to generate an uncorrectable flag indicating that the data is error data when error-uncorrectable data remains in the reproduced data.

The data error-corrected by the ECC circuit 33 is supplied to the decoding circuit 34. The decoding circuit 34 is
The reproduction data is decoded and output by the reverse process of the encoding process applied to the reproduction data. For example, when the reproduction data is MPEG video data, the decoding circuit 34 performs MPEG standard expansion processing. If the reproduced data is AC3 compressed audio data, AC3
Perform standard expansion processing. Further, even when the reproduction data is character data such as subtitles or bitmap data, the decoding process according to the encoding process performed on the reproduction data is performed. Also, the playback data is M
If a PEG2 standard program stream or transport stream is configured, a decoding circuit
The 34 also performs system decoding and the like for interpreting the meaning of data. The output of the decoding circuit 34 is output to a display circuit, an output circuit, or the like (not shown).

In the present embodiment, the decoding circuit 34
Outputs the information indicating the type of data being decoded or the decoding result itself to the video / audio data determination unit 37. The video / audio data determination unit 37 determines whether the data to be decoded is data (hereinafter, referred to as real-time data) that needs to be read within a fixed time, such as moving image data or audio data, or , Programs and spreadsheet files,
It is determined whether the data has no time constraint in reading, and the data type determination result is used as the error impact degree determination unit 36
Output to U35.

An uncorrectable flag from the ECC circuit 33 is also given to the error influence degree determination unit 36. Error impact determination unit
36 determines the influence of the uncorrectable error on the decoding process of the decoding circuit 34 and the process of the circuit at the subsequent stage (not shown) based on the uncorrectable flag and the data type determination result, and outputs the influence degree determination result to the CPU 35. . For example, the error influence degree determination unit 36 outputs the influence degree determination result for instructing the retry operation only when the uncorrectable bit causes a practical problem in the restored data from the decoding circuit 34.

The data type determination result and the error influence degree determination result are input to the CPU 35, and the uncorrectable flag is also input from the ECC circuit 33. The CPU 35 controls the retry operation based on not only the uncorrectable flag but also the data type determination result and the error influence degree determination result. For example, if the reproduction data is indicated as data other than real-time data based on the data type determination result, the CPU 35 instructs the retry operation based on the uncorrectable flag as in the conventional case.

Further, when the reproduction data is shown to be real-time data based on the data type determination result, the CPU 35 determines whether to perform the retry operation based on the influence degree determination result. Further, even when the reproduction data is real-time data, the CPU 35 is similar to the conventional case when it is not necessary to complete the reading of the data within a predetermined time such as when copying the data. The retry operation is performed based on the uncorrectable flag.

The CPU 35 outputs retry instruction information to the head 31 to perform a retry operation. When the retry instruction information is supplied from the CPU 35, the head 31 reproduces the data again from the track position based on the retry instruction information.

Next, the operation of the embodiment configured as described above will be described with reference to the flowchart of FIG. FIG. 2 shows an operation flow when there is a possibility that compressed data such as the MPEG standard may be recorded on the disc 30.

The head 31 reproduces the data recorded on the disk 30 and outputs a reproduction signal to the RF circuit 32. The reproduction signal is amplified by the RF circuit 32, waveform-equalized, converted into a digital signal and reproduced as EC as reproduction data.
It is given to the C circuit 33. The ECC circuit 33 corrects an error in the reproduced data by using the error correction code included in the reproduced data. The error-corrected reproduced data is supplied to the decoding circuit 34, and is decoded by the reverse process of the encoding process performed on the reproduced data.

Now, it is assumed that the data recorded on the disk 30 is MPEG standard compressed data. In addition,
In the compressed data of the MPEG standard, a header is inserted every predetermined number of frames (GOP (Group of Picture)), and it is possible to determine that the data is the compressed data of the MPEG standard by this header. In addition, a code for discriminating whether the data is video data, audio data, or other data is arranged at a predetermined position in the header. By determining this code,
It is possible to determine the type of data of the MPEG standard.

If no error has occurred in the reproduced data or if the number of error bits that have occurred does not exceed the error correction capability, the ECC circuit 33 reliably corrects the error bits. In this case, the CPU 35 does not perform the retry operation.

On the other hand, it is assumed that the number of error bits of reproduced data exceeds the error correction capability. Then, the ECC circuit
Reference numeral 33 indicates an uncorrectable flag indicating that the error bit could not be corrected, and the error influence degree determination unit 36 and the CPU
Output to 35. On the other hand, the decoding circuit 34 uses the ECC circuit 33.
The reproduction data from is decoded. In this case,
Since the reproduced data is MPEG standard compressed data, the decoding circuit 34 performs MPEG standard decoding and decompression processing.

In the present embodiment, the decoding circuit 34
Decodes the reproduction data and outputs the header portion to the video / audio data determination unit 37. Video / audio data determination unit 37
Determines from the input header that the reproduced data is MPEG standard compressed data. Further, in step S1 of FIG. 2, the video / audio data determination unit 37 determines whether the reproduction data to be decoded from the contents of the header is a video data part, an audio data part, or another data part. Determine.

For example, it is assumed that the reproduction data is other data. The video / audio data determination unit 37 outputs a data type determination result indicating that the data type is other data to the CPU 35. Since the other data is not real-time data, the CPU 35 instructs the head 31 to perform the retry operation.

As a result, the head 31 retraces the portion where the error has occurred and outputs a reproduction signal to the RF circuit 32. After that, the retry operation is performed by the same processing. The retry operation is repeated within a predetermined number of times until the correct data is restored, as in the conventional case. If the real-time data such as video data and audio data cannot be normally reproduced by retrying other data, the CPU 35 does not instruct the retry operation.

Next, it is assumed that the reproduction data to be decoded by the decoding circuit 34 is audio data. In this case, when the error influence degree determination unit 36 detects from the data type determination result that the reproduced data is audio data, it determines in step S3 whether the audio data is compressed data or uncompressed data. To do.

Now, it is assumed that the data recorded on the disk 30 is uncompressed audio data which is not compressed according to the MPEG standard or the like. In this case, the error impact degree determination unit
36 detects from the uncorrectable flag whether or not it is a slight error. For example, even if video data or audio data is not compressed, even if a 1-bit error occurs, interpolation processing or mute processing is performed to restore the quality without any practical problems. It is possible. For this reason, when the error is minor, the error influence degree determination unit 36 does not instruct the retry operation even if the error has occurred. This makes it possible to prevent the sound from being interrupted when sound is output using the restored sound data.

On the other hand, it is assumed that the reproduction data is compressed data of MPEG standard or the like. In this case, the error influence degree determination unit 36 determines that the influence of the bit error is large, and outputs the influence degree determination result for instructing the retry operation to the CPU 35. As a result, in this case, the retry operation is performed.

Next, it is assumed that the reproduction data to be decoded by the decoding circuit 34 is video data. In this case, when the error influence degree determination unit 36 detects from the data type determination result that the reproduction data is video data, it determines in step S2 whether the video data is compressed data or uncompressed data. To do.

It is assumed that the data recorded on the disk 30 is uncompressed video data which is not compressed according to the MPEG standard or the like. Even in this case, as with the audio data, it is possible to obtain an image of a quality that has practically no problem for minor errors. The error impact degree determination unit 36,
If it is determined from the uncorrectable flag that the error is a minor error, no retry operation is instructed. As a result, when an image is displayed using the output of the decoding circuit 34,
It is possible to prevent the image from being discontinuous.

On the other hand, it is assumed that the reproduction data is MPEG standard compressed video data. In this case, in the next step S4, the error impact degree determination unit 36 determines that the video data is an intra-frame compressed frame (hereinafter referred to as an I picture).
Or an inter-frame compressed frame (hereinafter referred to as B or P picture). In the MPEG standard, in addition to intraframe compression for compressing images within a frame, interframe compression for compressing a difference between images of two frames by utilizing correlation between frames is adopted.
The amount of data can be further reduced by using the inter-frame compression.

As described above, since the I picture compresses the image in the frame, even if an error occurs, the influence on the image is relatively small. For this reason, the error influence degree determination unit 36 does not instruct the retry operation when the video data is an I picture. As a result, it is possible to prevent the image from being interrupted when an image is displayed using the output of the decoding circuit 34.

On the contrary, in the B and P pictures, the restored image is significantly deteriorated due to the occurrence of an error. Therefore, when the reproduced data is a B or P picture, the error influence degree determination unit 36 outputs the influence degree determination result for instructing the CPU 35 to perform the retry operation.

As described above, in the present embodiment, the video / audio data determination unit determines whether or not the reproduction data is real-time data. If the reproduction data is real-time data, the error influence degree determination unit determines that an error has occurred. It is judged from the uncorrectable flag whether or not the deterioration of quality, which is a problem in practical use, will occur due to the influence of (1), and the retry operation is controlled not to be performed when no serious error has occurred. As a result, it becomes possible to read data, such as video data or audio data, which needs to be read within a fixed time, within a fixed time, resulting in deterioration of quality and unreproducibility. Is being prevented.

If another circuit has a function of determining whether or not the data is compressed data, it is not necessary for the error influence degree determining unit to have this function. Further, the determination result of the system decoding from the decoding circuit or the like may be used.

In this embodiment, MPEG is used.
Although the description has been given by taking the compressed data of the standard as an example, the file formats of other files such as AVI files, which are video and audio file formats defined by Microsoft Corporation, are standardized. It is obvious that the processing should be performed.

FIG. 3 is a block diagram showing another embodiment of the present invention. In the embodiment of FIG. 1, the type of data and the data content at each position are determined from the reproduced data.
On the other hand, in the case of a removable disk such as a DVD, information indicating that the disk is a DVD or the like is TOC.
It is recorded in (Table of Contens) (system information area). Therefore, without determining the type of data, T
The type of disk can be discriminated from the OC data, and the type of error data can be discriminated based on the discrimination result. The present embodiment is an example applied to this case. In FIG. 3, the same components as those in FIG. 1 are designated by the same reference numerals and the description thereof will be omitted.

In this embodiment, a decode circuit 44 is used instead of the decode circuit 34, and the error influence degree determination unit 36 is used.
1 is different from the embodiment of FIG. 1 in that an error influence degree determination unit 46 and a DVD disc determination unit 47 are provided in place of the video / audio data determination unit 37.

The decoding circuit 44 decodes the reproduction data by the reverse processing of the encoding processing applied to the reproduction data. Further, the decoding circuit 44 can perform system decoding of the reproduction data to detect that the disc 30 is a DVD disc. Further, the decoding circuit 44 obtains information on the type of data recorded on the disk 30 and its recording position by decoding the system area of the disk and TOC or the like. In addition, the decoding circuit 44,
Decoding of MPEG standard video data and decoding of AC3 standard audio data can be performed.

The decoding result of the system decoding of the decoding circuit 44 is supplied to the DVD disc determining section 47. The DVD disc determination unit 47 determines whether or not the disc 30 is a DVD disc based on the system decoding result, and outputs it to the error influence degree determination unit 46 and the CPU 35 as the disc determination result. In addition, the disk 30
Information regarding the type and recording position of the data recorded on the disk is also supplied to the error influence degree determination unit 46 and the CPU 35.

The CPU 35 determines, according to the disc determination result,
When it is detected that the DVD disc is being reproduced, whether or not to perform the retry operation is determined based on the influence degree determination result from the error influence degree determining unit 46.

The error influence degree determination unit 46 determines whether or not there is a problem in the decoding processing in the decoding circuit 44 and the processing of the circuit in the subsequent stage even if the uncorrectable bit remains an error. The error impact degree determination unit 46 prohibits the retry operation when the quality with no practical problem is obtained even when the data including the error is used, and the impact degree determination for instructing the retry operation only when it is not. It is designed to output the result.

Next, the operation of the embodiment thus constructed will be described with reference to the flowchart of FIG.

The operation when there is no error in the reproduced data or when the number of error bits that have occurred does not exceed the error correction capability is the same as in the embodiment of FIG.

It is assumed that the disc 30 is a DVD disc and an error exceeding the error correction capability has occurred in the reproduced data. In this case, the ECC circuit 33 outputs an uncorrectable flag indicating that the error bit could not be corrected to the error influence degree determination unit 46 and the CPU 35. On the other hand, the decoding circuit 44 decodes the reproduction data from the ECC circuit 33.

The decoding circuit 44 detects and decodes the system area or TOC portion from the reproduced data in step S11 of FIG. This decoding result is supplied to the DVD disc determination unit 47. DVD disc determination unit 47
Determines whether the disc 30 is a DVD disc from the input decoding result in step S12.
The disk determination result is sent to the CPU 35 and the error influence degree determination unit 46.
Output to

When the disc determination result shows that the disc is not a DVD disc, the CPU 35 determines that the disc 30 has non-video data such as a program or non-audio data recorded therein, and the head 31 is turned on. Control and instruct retry operation.

On the other hand, when the disc determination result indicates that the disc is a DVD disc, the CPU 35 determines whether to perform the retry operation based on the influence determination result of the error influence determination unit 46. Error influence degree determination unit 46
Is also provided with information indicating the type of data and its recording position. In step S13, it is determined whether the error data is data in a region such as video or audio or data in a system region. When the error impact degree determination unit 46 identifies the error data as data in the system area, the error impact degree determination unit 46 outputs an impact degree determination result for instructing the retry operation. As a result, the CPU 35 instructs a retry operation and enables reliable reproduction of the system area.

Further, when the error influence degree judging unit 46 identifies that the error data is the data in the non-system area, that is, the video data or the audio data, the influence of the error is small and it is necessary to retry. Outputs the error impact degree determination result indicating that there is no error. As a result, when data such as video data and audio data is being reproduced,
No retry operation is performed. Therefore, it is possible to prevent the image or the sound from being interrupted when the video display or the sound display is performed using the output of the decoding circuit 34.

As described above, FIG. 1 is also used in this embodiment.
The same effect as that of the embodiment can be obtained. Also,
When playing a disc of a type specified in advance, it is possible to determine the area in which the retry operation is not performed,
It is possible to prevent the quality of the restored data of the real-time data from deteriorating.

In the present embodiment, the error influence degree determination unit 46 determines whether or not to retry depending on whether or not the erroneous data is recorded in the system area, but the retry may be performed according to other requirements. Obviously, it may be decided whether or not to do so.

Further, it is clear that a judging section having both functions of the video / audio data judging section 37 in the embodiment of FIG. 1 and the DVD disc judging section 47 in the embodiment of FIG. 3 may be used. Is.

Further, in each of the above-described embodiments, it is determined whether or not to retry, whether the reproduced data is compressed data, non-compressed data, I-picture, B, P.
Although it is performed by using the picture, the data in the system area, the data in the video or audio data area, and a combination thereof, the present invention does not limit the criterion for determining whether to retry. Absent.

For example, even when the reproduced data is uncompressed data, the difference from the correct value, that is, the degree of adverse effect is extremely different depending on whether the error bit is the upper bit or the lower bit. In consideration of the above, it may be added to the determination criterion whether it is the upper bit or the lower bit. In addition, whether or not interpolation and prediction using other data is possible, whether or not replacement by data on the preceding and following time axes, interpolation and prediction, etc. are possible, and in the case of video data, color signal data Or luminance signal data, or whether there is a method of making an error inconspicuous, or the like may be used as a criterion.

Further, when the reproduced data is compressed data such as video, not only the judgment by I, B and P pictures but also whether the error portion is AC component or DC component,
In the case of data such as AC component, DC component, and motion vector, whether it can be estimated from other data, whether the next picture is restored based on the picture including the error portion, the pixel in which the error occurred Whether to restore other blocks or pixels based on, whether the error bit can be processed as "1" or "0" to infer the correct bit value, uncompressed data obtained by decoding It is possible to adopt various judgment criteria such as whether or not there is a method for taking measures.

Further, in each of the above-described embodiments, whether or not to retry is determined. However, if the video and audio are not interrupted even after retrying until the number of times has a time margin, "retry" is performed. You may replace “No” with the method of “limiting the number of retries to a range that does not affect the decoding of real-time data”.

In addition to the above criteria, various criteria may be used as long as it is possible to suppress the adverse effects of an error that has occurred.

[0067]

As described above, according to the present invention, it is possible to restore normal data even when a retry operation is performed.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a disc reproducing apparatus according to the present invention.

FIG. 2 is a flowchart for explaining the operation of the embodiment of FIG. 1;

FIG. 3 is a block diagram showing another embodiment of the present invention.

4 is a flowchart for explaining the operation of the embodiment of FIG.

FIG. 5 is an explanatory diagram showing a disk medium.

FIG. 6 is an explanatory diagram showing a disk medium.

FIG. 7 is a block diagram showing a conventional disc reproducing apparatus.

[Explanation of symbols]

30 ... Disk, 33 ... ECC circuit, 34 ... Decode circuit, 35
... CPU, 36 ... Error influence degree determination section, 37 ... Video / audio data determination section

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI Technical display location G11B 20/18 574 G11B 20/18 574D H04N 5/94 H04N 5/94 Z

Claims (2)

[Claims] 1. A reproducing device for reproducing information recorded on a disk medium to obtain reproduced data, and determining whether or not the reproduced data is data that needs to be read out within a fixed time. And a data type determining unit that determines the degree of influence of the error data on the processing quality of a predetermined process using the reproduction data when error data that cannot be corrected is generated in the reproduction data. And a control unit that determines whether to instruct the reproducing unit to perform a retry operation based on the output of the data type determining unit and the output of the influence degree determining unit. . 2. The data type determination means determines whether or not the reproduction data is data that needs to be read out within a fixed time by determining the type of the disk medium. The disk reproducing apparatus according to claim 1, wherein the disk reproducing apparatus is a disk reproducing apparatus.