JPH06103699A - Information reproducing device - Google Patents

Abstract

PURPOSE:To shorten the silent time at the time of changing disks in a changer type MD system. CONSTITUTION:Data read out of a disk 1 are once stored in a buffer memory 16, and a data amt. in the buffer memory 16 is calculated from write and read addresses for the buffer memory 16. Then, when the data amt. becomes below a reference value, data read from the disk 1 are written in the buffer memory 16. The reference value 36 is increased just prior to the completion of the disk 1 during reproducing, and enough information not to interrupt a sound during the time of changing disks is accumulated in the buffer memory 16, so that continuous reproducing can be carried out.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for reproducing an information signal such as a digital audio signal from a disc.

[0002]

2. Description of the Related Art Recently, digital audio equipment using an optical disk has been developed. A compact disc (hereinafter referred to as "CD") player is well known as a read-only system, and a write-once optical disc system that can be written only once is available as a recordable system. Furthermore, a magneto-optical type optical disc system capable of recording any number of times is being developed. As an example,
Nikkei Electronics December 9, 1991 p. 16
0-p. There is a mini disk (MD) system disclosed in the article "Mini disk, realized by magneto-optical recording and data compression technology" in 168. The MD system records and reproduces audio signals compressed on a disk by a magneto-optical method. A guide groove for tracking control is formed on the disk in advance, and the guide groove is continuous over the entire circumference of the disk. The address information that is specifically assigned is recorded. Therefore, the search is possible regardless of the presence or absence of the recording signal.

FIG. 20 is a block circuit diagram of the MD system. In the figure, 101 is a 2-channel audio input terminal, 102 is an analog / digital conversion circuit (A
/ D converter), 103 is an encoder, 104 is a recording memory, 105 is a recording signal processing circuit that adds an error correction code and modulates a signal, and 106 is a clock generation circuit that generates and supplies a clock required for each circuit of the system. , 107
Is a recording head drive circuit, 108 is a recording magnetic head, 1 is a disk, 2 is an optical pickup, 3 is a reproduction amplifier, 6 is a reproduction signal processing circuit for performing demodulation and error correction, 16 is a buffer memory, 17 is a decoder, and 7 is Digital / analog conversion circuit (D / A converter), 8 is a 2-channel audio output terminal, 18 is an address decoder, 11 is a microcomputer, 12 is a servo circuit, 13 is a disk motor, 14 is a key input, and 15 is a display circuit. is there.

FIG. 21 is a timing chart of signal processing during recording and reproduction. The operation will be described with reference to FIGS. 20 and 21. During recording, the analog audio signal supplied to the audio input terminal 101 is sampled by the A / D converter 102 and converted into a digital signal. This digital audio signal is an encoder 103
The data is compressed and coded in to be reduced to about 1/5 of the original information amount.

The compressed signal is temporarily stored in the recording memory 104 and is intermittently read out at the same rate as before compression as shown in FIG. By intermittently reading, the difference between the data writing rate to the memory and the reading rate from the memory is absorbed. Recording signal processing circuit 10
In No. 5, the interleaving process for rearranging the signal order in order to disperse the error at the time of reproduction, the error correction code is generated and added, and the signal is modulated. This modulated signal is magneto-optically recorded on the disk 1 from the recording magnetic head 108 via the recording head drive circuit 107. The recording operation is performed in response to the intermittently supplied modulated signal (FIG. 21C), and as shown in FIG. 21D, the signal recording operation and the recording pause are alternately repeated to perform recording. Before doing so, search for the last address of the part that has been recorded up to that point and record it in succession.

At the time of reproduction, the optical pickup 2 irradiates the disc 1 with light and the reflected light reads the signal written on the disc 1. This optical information is converted into an electric signal by the optical pickup 2 and supplied to the reproduction amplifier 3. The signal amplified by the reproduction amplifier 3 is given to the reproduction signal processing circuit 6, and EFM (Eight to Fo) is applied.
The signal is output to the buffer memory 16 after being demodulated by a method such as U.T.en Modulation), subjected to error detection and correction processing, and deinterleaving processing to restore the order of signals.

On the other hand, the output of the reproduction amplifier 3 is also supplied to the address decoder 18. This address decoder 18
Aims to take out address information contained in the guide groove of the light spot engraved in advance on the disc 1, reproduces the address signal continuously attached to the entire circumference of the disc, and detects the wobbling of the guide groove. To get tracking information. This tracking information is supplied to the servo circuit 12, tracking servo is applied so that the optical pickup 2 scans a predetermined guide groove, and the disc 1 is rotated at a constant linear velocity so that the undulation of the guide groove has a constant cycle. Then, the disk motor 13 is controlled by applying a servo maintained at.

The signal reading from the disk 1 is performed intermittently like the writing at the time of recording. As shown in FIGS. 21 (e) and 21 (f), the reproducing operation and the reproducing pause state are alternately repeated, The signal read from the buffer memory 16 is given to the decoder 17, the audio signal restored to the information amount before compression is converted into an analog signal by the D / A converter 7, and then output from the audio output terminal 8. It The microcomputer 11 receives the address signal engraved in the disc guide groove from the address decoder 18 and the address signal recorded corresponding to the audio signal, and further receives the key input 14 from the outside to receive the entire system. Control. Further, the display circuit 15 is driven to display information such as the operation mode of the system and the elapsed playback time.

In this system, the optical pickup 2 reads a signal from the disc 1 at a rate of about 1.4 Mbits / sec (Mbps). On the other hand, since the input rate to the decompression circuit 17 is about 0.3 Mbps, when the 1 Mbit buffer memory 16 is used, the buffer memory 16 becomes full when the disk is read for about 0.9 seconds. In addition, it is possible to reproduce for about 3 seconds with the compressed data filled in the buffer memory 16. Therefore, for example, even if the optical pickup 2 jumps due to a disturbance, the data is held in the buffer memory 16, so that the sound is not interrupted immediately, and the portion immediately before the jump is performed before the signal in the buffer memory 16 disappears. By searching and writing the signal in the buffer memory 16, continuous reproduction can be performed without sound interruption.

Further, by loading a plurality of discs into the device,
As an information reproducing device that selects and reproduces one of them,
There are magazine-type changer CD players for in-vehicle or stationary. FIG. 22 is a block circuit diagram of a conventional magazine type changer CD player. Load 6 to 10 CDs into one magazine and load the magazine into the player's changer mechanism 100. After that, the CD designated by the user is pulled out from the magazine, mounted on a disc mechanism (not shown) and played. Therefore, if the user operates the disc change key to play another disc while playing a disc, first stop the disc that is currently playing and then store it in the magazine. The specified disc is pulled out from the magazine, mounted on the disc mechanism and rotated to start the playback operation.

When a disc is exchanged in such a changer type information reproducing apparatus, it is necessary to perform the following processing from the end of the reproduction of the disc until the reproduction of the next disc, which is considerably It takes time. 1. Stop spinning the disc. 2. The disc that has been played back is stored in the magazine. 3. The disc to be played next is taken out from the magazine. 4. Mount the disc. 5. Rotate the disc. 6. TOC (Table Of Contents)
Read information.

[0012] Usually, a CD often includes a silent portion of about 2 to 3 seconds at the end of the program, and about 2 seconds from the end of the program to the start of the above-mentioned processing. It takes ~ 3 seconds, and the silent time when exchanging the disc is further increased.

As described above, the time required for the disc change takes at least several seconds, and during this period, the silent state in which the reproduced sound is not output continues, so that the speed of the disc change mechanism has been conventionally increased to shorten the silent period. There was a limit but there was a limit. Therefore, Japanese Patent Laid-Open No. 3-273586 discloses an example of eliminating a silent period by using a memory. With this device, the CD is faster than the playback speed.
Signal is read from the memory and stored in a memory, and the signal is read from the memory at a predetermined reproduction speed. Then, during the silent time of the disk change, the signal stored in the memory is continuously read to substantially eliminate the silent time.

[0014]

Since the conventional MD system is configured as described above, when the pickup 2 causes a track shift due to an impact when there is little data in the buffer memory 16 at the time of reproduction, the buffer memory 16 is not available. The data in may become empty immediately and sound may be interrupted. Further, since the data is delayed in the buffer memory 16, if the address or time information reproduced by the optical pickup 2 is displayed as it is, a different one from the one corresponding to the data output from the terminal 8 is displayed. Become.

Further, in the conventional changer type information reproducing apparatus, when reproducing a plurality of CDs in a predetermined order and in a predetermined music order, the silent time is eliminated or shortened. However, if the user forcibly specifies the disk change during reproduction, there is a problem in that there is no effect of shortening the silent time because the necessary signal is not stored in the memory.

The present invention has been made in order to solve the above problems, and is a time from the end of the reproduction of the program of one disc to the start of the reproduction of the program of the next disc. It is an object of the present invention to provide a disc reproducing device capable of shortening the time.

It is another object of the present invention to provide a system in which the capacity of the memory is effectively used and the sound is not interrupted as much as possible when a track shift occurs due to a vibration.

It is another object of the present invention to provide a changer type disk device in which a silent time that occurs when a disk is replaced is short.

It is another object of the present invention to provide an information reproducing apparatus which corrects and displays a reproduced address or time information so as to correspond to that of a signal which is outputting.

Further, by significantly reducing or eliminating the silent time at the time of disc change, even when reproducing a plurality of discs, an information reproducing device which can be used with the same feeling as reproducing one disc, In particular, it is an object of the present invention to provide an information reproducing apparatus that can reduce the silent time even when the user forcibly specifies a disc change.

It is another object of the present invention to provide an information reproducing apparatus with good operability, which enables the contents of other discs to be known while reproducing a disc or the contents of all discs to be confirmed by ear. .

[0022]

According to a first aspect of the present invention, there is provided an information reproducing apparatus in which the amount of information stored in a memory for temporarily storing information read from a recording medium is a write address to the memory and a read at the time of writing. It is characterized by comprising means for calculating from the difference from the address and control means for storing the information read from the recording medium in the memory when the amount of stored information in the memory becomes equal to or less than the lower limit reference value.

In the information reproducing apparatus according to the second aspect of the invention, the amount of information stored in the memory for temporarily storing the information read from the recording medium is calculated from the difference between the memory write address and the read address at the time of writing. Means, a control means for storing the information read from the recording medium in the memory when the amount of information stored in the memory becomes equal to or lower than the lower limit reference value, and sub-information for specifying the position of the reproduction information on the recording medium. It is characterized in that it is provided with means for detecting and means for increasing the reference value when the reproduction position reaches a predetermined position.

In the information reproducing apparatus according to the third aspect of the invention, the amount of information stored in the memory for temporarily storing the information read from the recording medium is calculated from the difference between the memory write address and the read address at the time of writing. And a means for correcting and outputting the time information related to the output time of the reproduction information to the time information delayed by the time required for reading the stored information in the memory.

In the information reproducing apparatus according to the fourth aspect of the present invention, means for detecting the signal level of the reproduced information and the signal level of the information from the predetermined level within a predetermined time near the end of the reproduced information judged from the TOC information and the like. It is characterized in that it is provided with means for judging the end of the reproduction information when it becomes small, and means for immediately stopping the driving of the recording medium and shifting to the next processing when it is judged as the end.

The information reproducing apparatus according to the fifth aspect of the present invention includes means for detecting that the final information of the reproduction information is stored in the memory in which the reproduction information is once stored, and recording the final information immediately after the storage of the final information. And a control means for stopping the drive of the medium and shifting to the next operation before the final information is output.

In the information reproducing apparatus according to the sixth aspect of the present invention, means for detecting the signal level of the reproducing information and the signal level of the information from the predetermined level within a predetermined time near the end of the reproducing information judged from the TOC information and the like. A means for judging the end of the reproduction information when it becomes small, and the driving of the recording medium is stopped immediately after the information judged as the end is stored in the memory, and the next operation is performed before this information is output. And a control means for controlling the operation.

An information reproducing apparatus according to a seventh aspect of the present invention outputs a partial information memory for storing a head portion of reproduction target information of each of a plurality of recording media and information of a head portion of a recording medium to be reproduced next. Control means for terminating the medium change, reading the information following the head portion from the newly recorded recording medium to be reproduced, and continuously outputting the information at the head portion.

An information reproducing apparatus according to an eighth aspect of the invention is a partial information memory for storing a part of recorded information of each of a plurality of recording media as partial information and a partial information of a designated recording medium being selectively read and reproduced. And means for outputting.

An information reproducing apparatus according to a ninth aspect of the invention is a partial information memory for storing a part of recording information of each of a plurality of recording media as partial information and a partial information of a designated recording medium being selectively read and reproduced. A means for outputting, an auxiliary power source for backing up so that the stored information in the partial information memory is not lost when the power source of the device is cut off, and a means for detecting that the recording medium has been replaced with a new recording medium even while the power source of the device is cut off. A means for storing, in the partial memory, information of a part of the recording medium newly added by replacement after the power source of the device is turned on.

[0031]

In the information reproducing apparatus according to the first aspect of the invention, the amount of stored information in the memory is calculated from the difference between the write address of the information read from the recording medium to the memory and the read address of the stored information read from the memory at the time of this writing. When the amount of information stored in the memory becomes smaller than the lower limit, which is the reference value, the information read from the recording medium is controlled to be stored in the memory, and for example, the jumped pickup returns to the normal position. During this period, the memory is always stored with a sufficient amount of information so that the correct reproduction information can be continuously output.

In the information reproducing apparatus according to the second aspect of the invention, the amount of stored information in the memory is calculated from the difference between the write address of the information read from the recording medium to the memory and the read address of the stored information read from the memory at the time of this writing. When the amount of information stored in the memory becomes smaller than the lower limit of the reference value, the information read from the recording medium is controlled to be stored in the memory, and, for example, reproduction from the next recording medium is continued. In this case, the output is detected from the position of the information being reproduced on the recording medium until the reproduction information of the current recording medium is near the end and the information is reproduced from the next recording medium. The reference value, which is the lower limit value of the amount of information stored in the memory, is increased so that the following information is stored in the memory, and the minimum amount of information that should be stored is increased.

The information reproducing apparatus according to the third aspect of the present invention reads out the time information specifying the output time of this information together with the information to be output, and delays the time information by a time corresponding to the time when the output information is read from the memory. The time information is corrected and output, and once stored in the memory and output after a predetermined time, the actual output time and the time information are matched.

In the information reproducing apparatus according to the fourth aspect of the invention, for example, in the vicinity of the final stage, the level of the reproduction signal of the music information such that the output signal becomes lower than the audible limit level is detected, and the reproduction is judged from the TOC information or the like. Within a predetermined time near the end of information,
The time when the signal level of the information drops below a predetermined level is judged to be the end time of the information reproduction, the drive of the recording medium is immediately stopped, and the next process such as the drive of the recording medium to be reproduced next is performed and no sound is produced. Save time as much as possible.

The information reproducing apparatus according to the fifth aspect of the invention stops driving the recording medium as soon as it detects that the final information of the reproducing information is stored in the memory for temporarily storing the reproducing information from the recording medium, Then, the process proceeds to the next process such as driving the recording medium to be reproduced next.

An information reproducing apparatus according to a sixth aspect of the present invention detects the signal level of reproduced information, and within a predetermined time near the end of reproduced information judged from TOC information or the like, the information signal level is below a predetermined level. It is judged that the time at which the information reproduction ends and the information at the end is detected to be stored in the memory, the drive of the recording medium is immediately stopped, and the next next reproduction such as the drive of the recording medium to be reproduced is performed. Move to processing.

In the information reproducing apparatus according to the seventh aspect of the present invention, the information of the head portion of the reproduction target information of the plurality of recording media, for example, in the case of music information, the head portion of the head music is stored in the partial information memory, When a medium change is instructed, the information of the beginning portion of the recording medium to be reproduced next is read out from the partial information memory and output, the medium change is completed during the output period, and the information continuing from the new recording medium to the beginning portion. Is read out and continuously output to the information of the head portion, and the silent time generated when the medium is changed is shortened as much as possible.

In the information reproducing apparatus according to the eighth aspect of the present invention, a part of the record information capable of grasping the recorded contents of the record information of the plurality of recording media is stored in the partial information memory as the partial information, and the specified recording medium is stored. It is possible to selectively read out the partial information from the partial information memory, reproduce and output the partial information, and grasp the contents of the recording medium without actually driving the recording medium.

In the information reproducing apparatus according to the ninth aspect of the present invention, a part of the record information that can specify the recorded contents of the record information of the plurality of recording media is stored as the partial information in the partial information memory and designated. Partial information of the recording medium is selectively read from the partial information memory and reproduced and output. Also, replacement of the recording medium is detected even when the power supply of the device is cut off, and the partial information of the recording medium newly added by the replacement is stored in the partial information memory. It is possible to grasp the contents of the recording medium without actually driving the recording medium.

[0040]

【Example】

Example 1. The information reproducing apparatus of the present invention will be described below with reference to the drawings. Incidentally, the same or corresponding parts as those of the conventional example are designated by the same reference numerals, and the description thereof will be omitted. FIG. 1 is a block circuit diagram of the first embodiment, in which the recording system is omitted and only the reproducing system is shown. In the figure, 16 is a buffer memory, 31 is a circuit for generating a write address of the buffer memory 16, 3
Reference numeral 2 is a circuit for generating a read address of the buffer memory 16, 33 is a selector, and 34 is a write flag generating circuit, which is a read address 32a and a write address 31a.
And the reference value input from the terminal 36, a write flag is generated. A write control circuit 35 controls writing to the buffer memory 16 by controlling a clock to the write address generation circuit 31 and a write pulse 35a to the buffer memory 16.

FIG. 2 is a memory map showing the relationship between the amount of data stored in a memory having an m-bit address and the write and read addresses, where W is the data being written and R is the data being read. . The write address and the read address are counted up from the address 0 to 2 ^m of the buffer memory 16.
It goes around -1. FIG. 2A shows the case where the write address is larger than the read address, and the shaded area shows the amount of data stored in the buffer memory 16. The wider the shaded area, the reproduction time after the writing is stopped. Can be taken for a long time. FIG. 2B shows a case where the address further advances from FIG. 2A, the address of W returns to 0, and the count is further increased to make R an address larger than W.

Next, the operation will be described. The data whose error has been corrected by the reproduction signal processing circuit 6 is based on the write address generated by the write address generation circuit 31.
The data is written in the buffer memory 16 intermittently. When writing, it is written at a rate of 1.4 Mbps. on the other hand,
The data stored in the buffer memory 16 is continuously read at 0.3 Mbps based on the address generated by the read address generation circuit 32. The write flag generation circuit 34 calculates the amount of data remaining in the buffer memory 16 from the difference between the write address 31a and the read address 32a, and the calculated data amount is the terminal 3
When the value becomes less than the first reference value E input from 6, the write flag is set to “0” (write enabled), and the calculated data amount is selected in advance from the maximum address value “2 ^m ” or a value smaller than 2 ^m near it. When it becomes equal to or larger than the second reference value F, the write flag is set to "1" (write prohibited).

The write control circuit 35 controls the write address generation circuit 31 to generate an address for writing the data reproduced from the disk 1 into the buffer memory 16 when the write flag is "0", and also the buffer memory. The write pulse 35a is output to 16. On the contrary, when the write flag is "1", the supply of the clock to the write address generation circuit 31 is stopped so that the write address is not updated, and the supply of the write clock to the buffer memory 16 is stopped.

As described above, when the data amount in the buffer memory 16 decreases to the first reference value E or less, the buffer memory 16 writes the data, and the second amount indicating immediately before the data amount in the buffer memory 16 overflows. When the value increases to the reference value F, writing is prohibited until the amount of data in the buffer memory 16 decreases to E again.

FIG. 3 is a diagram showing changes in the amount of data in the buffer memory 16, in which the horizontal axis represents time and the vertical axis represents the amount of data in the buffer memory 16. FIG. FIG. 3B shows an example in which one reference value E is large, and FIG. 3B shows an example in which it is small. In the case of FIG. 3A, a large amount of data is always stored in the buffer memory 16, which is advantageous for vibration. Further, in the case of FIG. 3B, since the write-protection period is long, this period can be used for reproduction of another system. The value of the first reference value E is set from the terminal 36 according to the application.

When the optical pickup 2 causes a track shift, the address decoder 18 detects it and outputs it to the write control circuit 35. Write control circuit 3
In the case of track deviation 5, writing is prohibited until the address returns to normal even if the amount of data in the buffer memory 16 becomes E or less.

FIG. 4 is a block circuit diagram showing an example of the configuration of the write flag generation circuit 34. Reference numeral 40 is a subtracter for subtracting the read address value 32a from the write address value 31a, and 41 is the polarity of the output of the subtractor 40. A polarity determiner that outputs “0” if it is positive and “2 ^m ” if it is negative, 42 is an adder, and 43 is a comparator that determines the magnitude of the output of the adder 42 with respect to the reference value. Subtractor 40,
The polarity determiner 41 and the adder 42 constitute an arithmetic unit 44 that calculates the amount of data remaining in the buffer memory 16.

In the case of FIG. 2A, since the output of the subtractor 40 is positive, the output of the adder 42 is the same as the output of the subtractor 40. Further, in the case of FIG. 2B, since the output of the subtractor 40 is negative, the adder 42 adds “2 ^m ” to the value of the subtractor 40 and outputs the result. In this way, the polarity determiner 41 outputs the data amount remaining in the shaded memory in FIG. 2 as a positive value. The comparator 43 outputs "1" when the output of the adder 42 becomes smaller than the first reference value E, and when the output reaches the second reference value F defined around 2 ^m , the buffer memory 16 overflows. In order not to do so, “0” is output and the write control circuit 35 controls to inhibit writing.

Example 2. FIG. 5 is a block circuit diagram showing a second embodiment of the information reproducing apparatus of the present invention.
It is a sub-information extracting circuit for extracting position information on the disc or time information corresponding to elapsed playing time from the signal reproduced from. In this embodiment, a plurality of discs 1 is used.
Is a changer type system that stores all the discs in a magazine and can continuously play all discs or select programs. In the CD changer system, when the disc being played is finished, it is automatically replaced with the next disc. Playback continues, but a silent period of about 10 to 15 seconds occurs when the disc is replaced.

A 1 Mbit RAM is used as a buffer memory 16
In this case, in the MD system, a compressed signal corresponding to a reproduction time of 3 seconds is stored in the memory, so that a compressed signal equivalent to 12 seconds can be stored when a 4 Mbit memory is used. The second embodiment is intended to reduce the silent time at the time of disc change by utilizing this.

Next, the operation will be described. Key input 14
Specifies continuous reproduction or program reproduction. In the case of program reproduction, the disk number and station number of the music to be reproduced are further specified. These designations are made by the microcomputer 11
Is stored in an internal memory (not shown) of the disc, and the microcomputer 11 determines from the address or time information indicating the position on the disc extracted by the sub-information extracting circuit 50 that the last song to be reproduced on the disc being reproduced ends. It is determined whether or not. The last song is the last song of the disc in the case of continuous play, and the last song programmed in the disc in the case of program play. By reading the TOC information recorded on a part of the disc, the start and end positions of each song or time information can be obtained.

When the microcomputer 11 determines that the music has ended, it sets the write stop signal 11b to the stop mode, outputs it to the write control circuit 35, and prohibits writing the reproduction signal to the buffer memory 16. In the prohibited state, the write address is not updated, and the write clock supplied to the buffer memory 16 is not output.

Next, when the disk 9 is replaced and the demodulated signal is normally reproduced, the demodulated OK signal 6a is output from the reproduced signal processing circuit 6. When the microcomputer 11 detects this signal, it sets the write stop signal 11b to the release mode. The write control circuit 35 writes the song of the new disc 1 into the buffer memory 16 while updating the address again, and the last song of the previous disc 1 and the first song of the new disc 1 are almost continuous in the buffer memory 16. Since it is stored as a file, the silent time when the disc is replaced is shortened.

By changing the capacity of the buffer memory 16, the time absorbed by the delay of the output with respect to the input to the buffer memory 16 can be arbitrarily selected. However, if a memory having an excessively large capacity is used, the absorption time becomes long, and when only one disc is reproduced, a sound is produced even after the reproduction of the disc 1 is stopped, which gives a feeling of strangeness. So if you use a large amount of memory, only if it is programmed to play the next disc
As shown in FIG. 3 (a), it is better to increase the first reference value E to store a large amount of data in the buffer memory 16. However, when the system is placed in another room or the like to hear the sound, the first reference value E may be kept high at all times.

Example 3. 6 is a block circuit diagram showing a third embodiment of the information reproducing apparatus of the present invention. Reference numeral 51 is a register for holding the output of the address decoder 18, 52 is an arithmetic unit for forming the output of the register 51 in the write flag generating circuit 34. This is an address correction circuit that performs correction using the output of 44 (see FIG. 4).

As described above, the larger the capacity of the buffer memory 16, the longer the delay time in the buffer memory 16. Therefore, the address decoder 1
The address data extracted in 8 is used by the microcomputer 1
When 1 is converted into time data and displayed, the deviation between the music output from the output terminal 8 and the displayed time information becomes large. For example, when a delay of up to 12 seconds is generated using a 4 Mbit memory, when it is displayed that 12 seconds have passed since the performance changed to song number 2, the music of song number 2 is output to terminal 8 Will be output from.

The present embodiment eliminates such an inconvenience, and the register 51 latches the address output from the address decoder 18. Buffer memory 16
The register 51 is updated while writing to the register is performed, but is not updated while writing is prohibited. Therefore, it can be said that the address of the register 51 is the latest data written in the buffer memory 16, and corresponds to the position information of the data stored at the write address or the designated address.

On the other hand, the output of the arithmetic unit 44 of the write flag generation circuit 34 is the difference between the read address and the write address. This is corrected by the address correction circuit 52 to the disk 1
Convert to the above address difference. Since the amount of data contained in one address is constant, this conversion can be easily calculated.
Then, the address correction circuit 52 outputs an address obtained by subtracting the obtained address difference from the address of the register 51 to the microcomputer 11. Microcomputer 11
Converts this into time and displays it. Since the address output from the address correction circuit 52 corresponds to the address of the data read from the buffer memory 16, there is no difference between the actual elapsed playing time of the music being played and the display time.

Since the delay times in the reproduction signal processing circuit 6 and the decompression circuit 17 are usually values that can be ignored, there is no problem if the delay time in the buffer memory 16 is corrected. When the time is obtained from the address reproduced from the disc 1, the microcomputer 11 converts the time information into the time information and displays it.

Further, in the second embodiment, the output of the sub information extraction circuit 50 is used to determine the end of the music, but the same effect can be obtained by using the output of the address decoder 18.

Further, in the third embodiment, the output of the address decoder 18 is used for the address correction, but the sub information extracting circuit 50 of FIG. 5 is provided and the same effect can be obtained by using this output.

Although the second reference value F is a fixed value in each embodiment, it may be arbitrarily set from the outside like the first reference value E.

Further, in each of the embodiments, the audio signal is taken as an example, but the same effect can be obtained if the device reproduces a digital signal.

Example 4. FIG. 7 is a diagram showing the configuration of the fourth embodiment of the information reproducing apparatus according to the present invention. In the figure,
1 to 5 and 7 to 15 are the same as the conventional example shown in FIG. 20 is an end detection circuit,
Detects the end of the program on the playing disc.

In this embodiment, the time-series digital audio signal restored to the original signal by the signal processing circuit 5 is input to the end detection circuit 20. The end detection circuit 20 determines that the program has ended when the level of the reproduced information signal becomes lower than a predetermined level by the end time of the program for one disc.

FIG. 8 shows a timing chart when the end of the program is detected. In the figure, (a) is a reproduction signal level,
(B) shows the operation mode of the conventional CD system, (c) shows the operation mode of the fourth embodiment.

It is already known that the program ends at the time t3, depending on the reproduction time of the music recorded in the TOC information of the CD, and in the conventional CD system, the time t3.
Then, the reproduction of the program ends, and the disc 1 stops here. However, in the embodiment according to the present invention, the end detection circuit 20 monitors the level of the reproduction signal for a predetermined time q seconds before the time t3 at which the program ends, and the predetermined time p
During the second (p <q), if there is no sound or a signal below the inaudible level (audible limit) that is very low, it is judged that there is no sound during the remaining time t2 to t3. Read from the disk 1 at time t2
The disc 1 is stopped, and the disc 1 is immediately stopped.

By doing so, compared to the conventional CD system, the time until the disc 1 stops can be shortened by s seconds, and this is applied to a system for automatically exchanging a plurality of discs. By doing so, it is possible to shorten the silent time when the disc is replaced, and thus it is possible to shorten the time from the end of the reproduction of the first disc to the start of the reproduction of the next disc. .

Example 5. In the fifth embodiment, the reproduced compression information is temporarily stored in a buffer memory, expanded, and output.
The buffer memory of the D system is used to further reduce the silent time when the disk is replaced. FIG. 9 is a diagram showing the configuration of this embodiment. In the figure, the same or corresponding parts as those of the conventional example and the above-described example are designated by the same reference numerals, and the description thereof will be omitted.

Next, the operation will be described. Deinterleaving, in which the signal written on the disc 1 is read by the optical pickup 2, the error of the signal sequence is corrected by the signal processing circuit 5, and the signal sequence in which the order of the signals is rearranged by the interleaving process is returned to the original order. The process is the same as the conventional device. The buffer buffer memory 16 and the expansion circuit 17
As shown in FIG. 10, under the control of the microcomputer 11, intermittently input data is temporarily stored, compressed data is expanded, and original time series data is continuously output. That is, the signal sequence input to the buffer buffer memory 16 between times t0 and t1 in the figure is from time t2 to t.
It is continuously output for 4 seconds. Similarly, from time t2
The signal sequences input during t3, t4 to t5, and t6 to t7 are time t4 to t6, t6 to t8, t8 to t, respectively.
Outputs continuously during 10. Also, the times t1 to t2, t
During the period from 3 to t4, t5 to t6, and t7 to t8 (the hatched portion in the figure), the writing of the buffer memory 16 is stopped.

The signal thus restored to the original continuous time-series data is passed through the D / A converter 7 to be output as an analog audio signal from the analog audio output terminal 8 and through the digital output circuit 9 as well. A digital audio signal conforming to the standard of the digital audio interface is output from the digital audio output terminal 1
It is output from 0. The microcomputer 11 performs various controls of the servo circuit 12, the signal processing circuit 5 and the like by the reproduced additional information and the key input 14, and displays information such as the operation mode and time of the system via the display circuit 15 through the display unit. To display.

In this embodiment, as in the second embodiment, the buffer buffer memory 16 is used to stop the disc before the reproduction signal ends, but the silent time is further shortened as compared with the second embodiment. FIG. 11 shows a timing chart at the end of the program. In the figure, (a) is the reproduction output of the conventional CD, (b) is the disc read timing of the second embodiment, (c) is the reproduction output of the second embodiment, and (d) is the disc read of the fifth embodiment. Timing, (e) shows the reproduction output of the fifth embodiment.

In the conventional CD system, as shown in FIG. 11A, the reproduction of the program is finished at time t5, the disc is stopped here, and the disc is replaced.
Start playback with. Therefore, there is no sound during the time k seconds required for disc replacement. However, in the second embodiment using the buffer buffer memory 16, as shown in FIGS. 11B and 11C, the reading from the disk 1 is completed at the time t3, and the buffer 11 is transferred to the buffer buffer memory 16 under the control of the microcomputer 11. Disc writing is finished, disc 1
Then, the disk exchange is started, and the reading from the next disk 1 is restarted at time t6. In this case, since the reproduction information signal is temporarily held in the buffer buffer memory 16, continuous time-series reproduction output continues until time t5, and reproduction output is restarted at time t9.
Assuming that the disk exchange time k seconds does not change,
In the case of this embodiment, the silent time is k−h seconds, which is shortened by h seconds.

Furthermore, in the fifth embodiment, the following operation can be performed. That is, in this Example 4,
When the reproduction of the disc 1 is restarted, as shown in FIG.
As shown in (e), when the microcomputer 11 controls so that the data read from the disk 1 for the first time is immediately decompressed and output, and is read from the second time as in the conventional case, the silent time becomes It is further shortened by i seconds. That is, as shown in FIGS. 11 (d) and 11 (e),
The data read from the disk 1 at times t6 to t7 is immediately expanded and output during the times t7 to t10, and the data read at times t7 to t8 is output after the time t10. By doing this, the silent time is further reduced by i
The time is shortened to kh-i seconds. In FIG. 11, the shaded portion is the silent portion.

Example 6. FIG. 12 is a block circuit diagram of a sixth embodiment of the information reproducing apparatus of the present invention. Note that the same or corresponding parts as those of the conventional example and the above-described embodiment are designated by the same reference numerals, and the description thereof will be omitted. In this embodiment, the end detection circuit 20 similar to that in the fourth embodiment is added to the MD system using the buffer memory for temporarily storing the compressed data. The time series digital audio signal restored to the original signal by the signal processing circuit 5 is input to the end detection circuit 20. The end detection circuit 20 determines that the program ends when the level of the reproduced information signal becomes lower than a predetermined level within the end time of the program for one disc.

FIG. 13 shows a timing chart when the end of the program is detected. In the figure, (a) is a reproduction signal level,
(B) shows the reproduction output of the conventional CD, (c) shows the disc read timing of the sixth embodiment, (d) shows the reproduction output of the sixth embodiment, and (e) shows the reproduction output of the seventh embodiment.

It has already been known that the program ends at time t6, depending on the reproduction time of the music recorded in the TOC information of the CD, etc.
At 6 the reproduction of the program is finished, the disc 1 is stopped here, the disc is exchanged, and then the reproduction is started at time t11. Therefore, there will be no sound during the disk replacement time of k seconds (hatched area Y), and there will be no sound at the end of the program or a signal below the inaudible level (audible limit) will be reproduced for h seconds. (The shaded portion X), there is a silent portion of substantially h + k seconds.

However, in the fifth embodiment using the buffer buffer memory 16 and the end detection circuit 20, the level of the reproduction signal for a predetermined time q seconds before the time t6 when the program ends is monitored, and the predetermined time p seconds. During (p <q), that is, between times t3 and t4, when there is no sound or a signal whose level is too low to be heard (audible limit) or less continues, the remaining times t4 to t6 When it is judged that all the data are silent, the reading of the compressed data from the disk 1 is stopped at the time t2, the disk 1 is immediately stopped, the disk exchange is started, and the reading from the next disk 1 is restarted at the time t7. . In this case, since the reproduction information signal is temporarily held in the buffer buffer memory 16, continuous time-series reproduction output continues until time t5, and reproduction output is restarted at time t9. Assuming that the time k seconds does not change, in the case of the fifth embodiment, the time for playing the silence is shortened by i seconds to h + k-i. In FIG. 13, the shaded portion X is the reproduction output, but it can be regarded as silence, and the shaded portion Y is the silence portion due to disk replacement or the like.

Example 7. Further, as shown in FIG. 13E, when the reproduction of the disc is restarted, the data read from the disc 1 for the first time is immediately expanded and output,
When reading from the second time as in the conventional case, the time for reproducing the silence is further shortened by j seconds to h + k-i-j seconds.

In the fourth to seventh embodiments, the level of the reproduction signal is used when detecting silence or low-level sound. However, in order to determine the level of the reproduction signal, for example, a reproduction signal such as a scale factor is used. You may use the value showing the range of.

In Examples 4 to 7, the reading from the disk 1 was stopped when there was no sound or a signal below the level (audible limit) where the level was too low to be heard. , May be a predetermined level, and in that case, the information after the reading from the disc 1 is terminated is output by approximating the reproduction signal as shown in FIG. 14 so that noise is not generated. You may.

Example 8. FIG. 15 is a block circuit diagram of an eighth embodiment of a changer type information reproducing apparatus of the present invention. In the figure, the same or corresponding parts as those of the conventional example or the above-mentioned embodiment are designated by the same reference numerals, and the description thereof will be omitted. 1 in the figure
9 is a low pass filter (LPF), 21 is an error correction circuit, 22 is a memory data input / output circuit, 23 is a first memory, 24 is an address control circuit for the first memory, 25 is a second memory, and 26 is a second memory. 2 is an address control circuit of the second memory. As in the conventional case, the reproduction signal demodulated by the demodulation circuit 4 is input to the error control circuit 21, subjected to error detection and correction processing, and deinterleave processing for returning the order of the interleaved signals to the original state. Done. The reproduced signal subjected to this processing is the memory data input / output circuit 22.
Is written in the first memory 23 under the control of the address control circuit 24 via. The reproduction signal once stored in the memory 23 is read out, and the memory data input / output circuit 22
Is given to the decoder 17 via.

Writing a signal to the first memory 23 is performed by
It is performed at a faster speed than reading from the first memory 23. That is, since the reading speed of the signal from the disk 1 is higher than the transfer speed of the output from the first memory 23, the signal amount in the first memory 23 increases. When the signal amount in the memory 23 reaches a predetermined amount (overflow set amount), the memory data input / output circuit 22 stops writing the signal to the memory 23. At the same time, the microcomputer 11 stores the position information on the disk at that time and controls the servo control circuit 12 to repeatedly search the position. During that time, the signal reading from the first memory 23 is continued at a constant speed, and when the signal amount in the memory reaches a predetermined amount (underflow setting amount), the memory data input / output circuit 22 writes the signal. To restart. Therefore, the first memory 23 holds at least a signal equal to or more than the underflow set amount. Therefore, for example, even if the optical pickup 2 jumps due to a disturbance or the like and a predetermined track cannot be scanned and the signal writing to the first memory 23 is stopped, the already held signal is continuously read and the jump is performed in the meantime. Continuous reproduction can be performed from the first memory 23 by searching the reproduction position immediately before the operation and returning the optical pickup 2.

When a disc is loaded in the information reproducing apparatus, the microcomputer 11 instructs the changer mechanism 100 to automatically pull out the discs one by one from the five discs and mount them in the disc mechanism. Playback of the loaded disc 1 is started in the same manner as during steady playback, but is played for the first predetermined time of the first music piece of each disc, for example, 10 seconds. At this time, the signal read by the optical pickup 2 is
Although it is supplied to the memory data input / output circuit 22 through the above-mentioned signal path, it is stored in the second memory 25 instead of the first memory 23. FIG. 16 is a conceptual diagram showing a data storage state of the second memory 25. Compressed signals for the first 10 seconds of the first music piece of each disk are stored in the areas 1 to 5 of the second memory 25, respectively. The correspondence between the disk number and the area on the memory is managed by the microcomputer 11.

Next, consider the operation when the user performs a disc change operation during reproduction of a disc.
FIG. 17 is a control flowchart explaining the operation at this time. First, when a disc change instruction is input by the key input 14 (S1), the microcomputer 1
1 mutes the audio output of the disc being reproduced (S2), and at the same time stops the disc rotation and issues a disc change command to the changer mechanism 100 to start the disc change (S3). Next, the memory address control circuit 26 is instructed to read the signal in the second memory 25 corresponding to the disk to be reproduced next, which is designated by the key input 14, from the memory, and the memory address control circuit 26 makes a predetermined signal. Address control of
The signals for the first 10 seconds of the first song of the corresponding disc are selected and read (S4). At this time, the memory data input / output circuit 22 selects a signal so that the signal read from the second memory 25 instead of the first memory 23 is supplied to the decoder 17. The signal restored by the decoder 17 is output from the audio output terminal 8 via the D / A converter 7 and the LPF 19 and from the digital audio output terminal 10 via the digital output circuit 9, and the mute is released (S5).

At this time, since the signal output from the second memory 25 is the compressed audio signal for 10 seconds, the audio reproduction for the first 10 seconds of the first music can be performed. During this period, the changer mechanism 100 changes the disc, and if the disc to be reproduced is loaded, the changer mechanism 100 searches for the position of the signal continuous with the audio signal for the first 10 seconds of the first music at high speed (S6). That is, since address information is recorded in the signal on the disc at predetermined intervals, the microcomputer 11 stores the final address of the signal first fetched in the memory 25, and searches for the next address consecutive to that address. To do.

Next, the optical pickup 2 reads the signal from the searched position, and the signal is stored in the first memory 23 in the same manner as the above-mentioned steady reproducing operation (S7). The signals stored in the second memory 25 are also output during this period. Then, after the corresponding last signal in the second memory 25 is output (S8), the memory data input / output circuit 22 is switched to output the signal from the first memory 23 (S9), and the memory address Control circuit 2
4 controls the memory address so that the fetched signals are sequentially read. Therefore, the signal stored in the memory 25 in advance is reproduced for the first 10 seconds, and the signal from the disk can be reproduced continuously from the continuation of the signal.

Example 9. FIG. 18 is a flow chart for explaining the operation of the MD changer system of the ninth embodiment. The system block configuration is the same as in FIG. First, when a disc is loaded, the compressed signals for the first 10 seconds of the first song of each disc are stored in the areas 1 to 5 in the second memory 25, as described above.

When the user wants to temporarily confirm the contents of another disc during the reproduction of one disc, he operates the corresponding key (S11).
1 controls to read the signal of the corresponding area in the second memory 25. That is, for the memory data input / output circuit 22, the output signal is switched from the signal in the first memory 23 to the signal in the second memory 25 (S12).
For the second memory address control circuit 26, the area 1
It is instructed to read out the signal of the area corresponding to the key operation of the keys 5 to 5 (S13). Then, after outputting the audio signal for 10 seconds (S14), the continuation of the disc that has been reproduced until then is reproduced (S15).

Next, for example, when the user wants to confirm the contents of all the disks, he operates the corresponding key, and the microcomputer 11 outputs the signal to be output to the memory data input / output circuit 22 at that time to the first memory. The signal in 23 is switched to the signal in the second memory 25. And the second
1 to 5 for the memory address control circuit 26 of
It is instructed to sequentially read out the signals. The signal read from the memory address control circuit 26 according to the memory address is supplied to the decoder 17 via the memory data input / output circuit 22 to restore the digital audio signal. Therefore, as the audio output, the first 10 seconds of the first tune of each disc are sequentially reproduced.
If the reproduction skip is instructed during the reproduction for 10 seconds, the microcomputer 11 instructs the second memory address control circuit 26 to jump to the first memory address of the area to be reproduced next. By doing so, you can easily skip.

Example 10. FIG. 19 is a block circuit diagram of Embodiment 10 of the information reproducing apparatus of the invention. In the tenth embodiment, it takes some time to reproduce a part of the information on all the disks. Therefore, if this is always done when the power is turned on, the user will have to wait a long time before starting reproduction. Therefore, if the disks are not replaced, the signals in the second memory 25 can be used as they are even if the power supply is cut off.
Back up with. Further, the changer mechanism 100 is provided with a disc detection switch 28 for detecting disc exchange of each disc. The microcomputer 11 monitors the presence / absence of disk replacement by the disk detection switch 28 even while the main power supply (not shown) is shut off, and if any of the disks is replaced, a new one is turned on after the next main power supply is applied. Controls to play some information only on the disc. Therefore, it is possible to eliminate the waiting time of the user after the main power is turned on when the disks are not replaced, and it is possible to reduce the waiting time when only some of the disks are replaced.

Of course, the device of the tenth embodiment can be applied to the eighth and ninth embodiments. In the above description, the signal stored in the second memory 25 is the first 10 seconds of the head music of each disk, but it may not be the head music and may be the first 10 seconds. It may be an appropriate amount of time on the way. However, in the eighth embodiment, since the disk change and the position search are performed while the signal in the second memory 25 is being output, it is necessary to be the information for the first few seconds of each disk, and further, there is no sound. In order to obtain a sufficient effect of shortening the time, a signal for a certain amount of time or more is required.

Further, in the eighth to tenth embodiments, the first memory 23 and the second memory 25 are described as different ones.
Obviously, the same functional operation can be realized by using the same memory and controlling the memory address.
Further, it is clear that the control according to the present invention can be realized without following the flow charts of FIGS. 17 and 18.

[0094]

As described above, in the information reproducing apparatus according to the present invention, since the minimum amount of data stored in the memory can be designated, even when the pickup causes a track shift, a normal sound can be produced. Can be set to the maximum value.

Since the write and read cycles to and from the memory can be changed depending on the minimum amount of data stored in the memory, a large cycle can be set for the convenience of performing reproduction signal processing for other systems. it can.

Further, in the disc changer type information reproducing system, since the amount of data stored in the memory can be controlled to the maximum when the disc is exchanged, the silent time when the disc is exchanged can be shortened.

Further, since the reproduced address or time information is corrected and displayed by using the difference between the write address and the read address of the memory, it can be displayed corresponding to the data output from the memory and the time lag is felt. Do not let

When ending the reproduction of the program,
The end of the program of the disk is detected from the output level of the signal immediately before the end of the program, and the disk is stopped immediately.So, if this is applied to the system that automatically replaces multiple disks, It is possible to reduce the time of silence during the replacement of the disk, and the disk can be replaced smoothly.

Further, since the reproduction program is temporarily held in the buffer memory, the disc can be stopped before the reproduction of the program is completed, and this can be applied to a system for automatically exchanging a plurality of discs. For example, it is possible to reduce the silent time when the disc is replaced, and the disc can be replaced smoothly.

Further, the reproduction program is temporarily held in the buffer memory, and the end of the program of the disc is detected from the output level of the signal immediately before the end of the program,
Since we decided to stop the disc immediately, you can stop the disc before the program finishes playing,
If this is applied to a system that automatically replaces a plurality of discs, the silent time when the discs are replaced can be shortened, and the discs can be replaced smoothly.

In addition, the music head portions of the head music pieces of a plurality of discs are reproduced in advance and stored in the storage means,
When the disc change key is operated, the beginning of the music piece corresponding to the disc to be reproduced next is output from the storage means, and the disc change is completed within that period, so that the disc output signal from the storage means is continuous. Since the position is searched and reproduced so as to be continuous with the output from the storage means, even if the disc is changed during the reproduction of a certain disc, the silent state associated with the disc change can be substantially eliminated. An excellent disc reproducing device can be obtained.

Further, the head portions of the head music pieces of the plurality of discs are respectively reproduced and stored in the storage means, and the plurality of music head portions are continuously reproduced from the storage means in response to a key operation, or the storage means. Since the beginning part of some songs is played from, you can know the contents of other discs while playing a certain disc, or you can check the contents of all discs with your ears. A disc reproducing apparatus is obtained.

Further, the head portions of the head music pieces of a plurality of discs are reproduced in advance and stored in the storage means, and the plurality of music head portions are continuously reproduced or stored from the storage means in response to a key operation. Play the beginning of some songs from the device, check the replacement of each disc by the disc detection device even while the power is off, and play the beginning of the beginning song only for the replaced disc. Since it is stored in the storage means and held as a signal to be reproduced,
When there is no disc replacement, there is no waiting time for the user after the main power is turned on, and even when only part of the discs are replaced, there is little waiting time for the user, but the silent state due to the disc change is virtually eliminated. It is possible to obtain a disc reproducing apparatus which can be eliminated physically, and which has an excellent operability in which the contents of other discs or the contents of all discs can be known.

[Brief description of drawings]

FIG. 1 is a circuit block diagram of an information reproducing apparatus according to a first embodiment of the present invention.

FIG. 2 is a conceptual diagram of a data storage state in a buffer memory according to the first embodiment.

FIG. 3 is a graph showing the relationship between the data amount in the buffer memory and the reference value E in the first embodiment.

FIG. 4 is a circuit block diagram of a write flag generation circuit according to the first embodiment.

FIG. 5 is a circuit block diagram of a second embodiment of the information reproducing apparatus of the present invention.

FIG. 6 is a circuit block diagram of a third embodiment of the information reproducing apparatus of the present invention.

FIG. 7 is a circuit block diagram of an information reproducing apparatus according to a fourth embodiment of the present invention.

FIG. 8 is a timing chart of disk drive stoppage between the information reproducing apparatus of Example 4 and a conventional CD system.

FIG. 9 is a circuit block diagram of a fifth embodiment of the information reproducing apparatus of the present invention.

FIG. 10 is a timing chart of the information reproducing apparatus of the fifth embodiment.

FIG. 11 is a timing chart of the information reproducing apparatus of the second and fifth embodiments and the conventional CD system.

FIG. 12 is a circuit block diagram of Embodiments 6 and 7 of the information reproducing apparatus of the present invention.

FIG. 13 is a timing chart of the information reproducing apparatus of Examples 6 and 5 and a conventional CD system.

FIG. 14 is a diagram showing an approximate output when reproduction is stopped by the information reproducing apparatus of Examples 4 to 7;

FIG. 15 is a circuit block diagram of an eighth embodiment of the information reproducing apparatus of the present invention.

FIG. 16 is a second information reproducing apparatus according to the eighth and ninth embodiments.
It is a conceptual diagram of a memory.

FIG. 17 is a flowchart of the operation of the information reproducing apparatus in the eighth embodiment.

FIG. 18 is a flowchart of the operation of Example 9 of the information reproducing apparatus of the present invention.

FIG. 19 is a circuit block diagram of an information reproducing apparatus according to embodiment 10 of the present invention.

FIG. 20 is a circuit block diagram of a conventional MD system.

FIG. 21 is a timing chart of a conventional MD system.

FIG. 22: Conventional magazine type changer type CD
It is a circuit block diagram of a player.

[Explanation of symbols]

 1 disk 2 optical pickup 3 reproduction amplifier 4 demodulation circuit 5 signal processing circuit 9 digital output circuit 11 microcomputer 12 servo circuit 13 disk motor 14 key input 15 display circuit 16 buffer memory 18 address decoder 20 end detection circuit 22 memory data input / output circuit 23 first memory 24 first memory address control circuit 25 second memory 26 second memory address control circuit 27 backup power supply 28 disk detection switch 31 write address generation circuit 32 read address generation circuit 34 write flag generation circuit 35 write Control circuit 44 Data amount calculation calculator 50 Sub information extraction circuit 51 Register 52 Address correction circuit 100 Changer mechanism

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical display location G11B 19/02 F 7525-5D 27/10 A 8224-5D (72) Inventor Manabu Tsukamoto Kyoto Prefecture Nagaokakyo No. 1 Ichibaba Institute, Electronic Product Development Laboratory, Mitsubishi Electric Co., Ltd. (72) Nobuaki Hirai, No. 1 Baba Institute, Nagaokakyo City, Kyoto Prefecture Mitsubishi Electric Corporation, Electronic Product Development Laboratory

Claims (9)

[Claims] 1. An information reproducing apparatus for reading information recorded on a recording medium, temporarily storing the information in a memory, and reading the stored information from the memory at a rate lower than a writing rate to the memory and outputting the information, from the recording medium. Means for generating a write address for writing the read information to the memory, means for generating a read address for reading the stored information from the memory, and means for setting a reference value indicating a lower limit value of the amount of information stored in the memory. Means for calculating the amount of information stored in the memory from the difference between the address for writing information to the memory and the read address for reading the stored information from the memory when writing the information, and the stored information When the amount becomes less than the reference value, the information read from the recording medium is written in the memory, and the stored information amount is An information reproducing apparatus comprising: a control unit that prohibits writing of information read from a recording medium to the memory when the capacity of the memory is exceeded. 2. An information reproducing apparatus for reading information recorded on a recording medium, temporarily storing the information in a memory, and reading the stored information from the memory at a rate lower than a writing rate to the memory and outputting the information, from the recording medium. Means for generating a write address for writing the read information to the memory, means for generating a read address for reading the stored information from the memory, and means for setting a reference value indicating a lower limit value of the amount of information stored in the memory. Means for calculating the amount of information stored in the memory from the difference between the address for writing information to the memory and the read address for reading the stored information from the memory when writing the information, and the stored information When the amount becomes less than the reference value, the information read from the recording medium is written in the memory, and the stored information amount is Control means for prohibiting writing of information read from the recording medium to the memory when the capacity of the memory is exceeded, and means for detecting sub-information for specifying the position of the information being read from the recording medium on the recording medium. An information reproducing apparatus comprising: a means for increasing the reference value when the information reproducing position reaches a predetermined position. 3. Along with the output information, the time information for specifying the output time of the output information is read from the recording medium, the output information is once stored in the memory, and then read from the memory at a rate lower than the writing rate to the memory. In the information reproducing device that outputs the time information while outputting
Means for generating a write address for writing the information read from the recording medium to the memory, means for generating a read address for reading the stored information from the memory, a write address for the information to the memory, and a means for writing the information. Means for calculating the amount of information stored in the memory based on the difference from the read address for reading the stored information from the memory, and correcting the time information to time information delayed by a time required to read the stored information from the memory. And an output unit for outputting the information. 4. An apparatus for reproducing information from a recording medium, a means for detecting a signal level of reproduced information, and a signal level of the reproduced information falling below a predetermined level within a predetermined time near the end of the reproduced information. An information reproducing apparatus comprising: means for judging the end of reproduction of the information; and control means for immediately stopping the driving of the recording medium and proceeding to the next processing when it is judged to end. . 5. An information reproducing apparatus for reading information recorded on a recording medium, temporarily storing the information in a memory, and reading the stored information from the memory at a rate lower than a writing rate to the memory to output the information. Means for detecting that the final information of is stored in the memory, and immediately after the final information of the reproduction target information is stored in the memory, the driving of the recording medium is stopped and the output of the final information stored in the memory is output. An information reproducing apparatus, comprising: a control unit that shifts to the next process before the end of. 6. Information reproduced by an information reproducing apparatus for reading information recorded on a recording medium, temporarily storing the information in a memory, and reading the stored information from the memory at a rate lower than a writing rate to the memory and outputting the information. Means for detecting the signal level of the reproduced information, a means for judging that the signal level of the reproduced information falls below a predetermined level within a predetermined time close to the end of the reproduced information, and a means for judging the end of the reproduction target information. When the information at the time is stored in the memory, the driving of the recording medium is stopped immediately, and a control unit that shifts to the next process before the output of the final information stored in the memory is completed is provided. Characteristic information reproducing device. 7. An information reproducing apparatus for reproducing information by exchanging a plurality of recording media according to a medium change command,
The partial information memory that stores the information of the head portion of the reproduction target information of each recording medium and the information of the head portion of the next reproduction target recording medium from the partial information memory when the medium change is instructed and output. And a control for ending the medium change while the information of the leading portion is being output, reading the information following the information of the leading portion from a new recording medium to be reproduced, and continuously outputting the information of the leading portion. An information reproducing apparatus comprising means. 8. An information reproducing device for reproducing information by exchanging a plurality of recording media according to a medium change command,
Partial information memory for storing a part of the record information of each recording medium as partial information, means for designating a recording medium from which the partial information should be reproduced from the partial information memory, and partial information for the recording medium designated by the means. An information reproducing apparatus comprising means for selectively reading out from an information memory and reproducing and outputting. 9. An information reproducing apparatus for reproducing information by exchanging a plurality of recording media in accordance with a medium change command,
Partial information memory for storing a part of the record information of each recording medium as partial information, means for designating a recording medium from which the partial information should be reproduced from the partial information memory, and partial information for the recording medium designated by the means. Means for selectively reading from the information memory, reproducing and outputting, auxiliary power source for backing up so that stored information in the partial information memory is not lost when the power source of the apparatus is cut off, and a recording medium included in the plurality of recording mediums. Means for detecting replacement of a recording medium not included in the plurality of recording media even during power-off of the device, and partial information memory for storing information of the part of the recording medium newly added by replacement after power-on of the device And a means for storing the information in the information reproducing apparatus.