JP3038848B2 - Information playback device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital signal information reproducing apparatus such as a compact disk player and a digital audio tape deck.

2. Description of the Related Art In recent years, many digital audio devices such as compact disc players have appeared on the market, and general users have enjoyed digital audio widely.

Hereinafter, a conventional information reproducing apparatus for a digital audio device will be described by taking a compact disc player as an example.

FIG. 4 is a block diagram of a conventional compact disc player. Hereinafter, the flow of a general digital signal will be briefly described with reference to FIG. The disk 2 is rotated by the rotation of the spindle motor 1, and an optical pickup 3 provided near the disk 2 reads a digital signal engraved on the disk 2. One of the signals is called an RF signal and enters the analog waveform shaping block 4 shown in FIG. 1 and the other is called a servo signal and enters a servo signal processing block 5. The servo signal is a detection signal for continuously and accurately reading pits, which are information engraved on the disk.

When the RF signal passes through the analog waveform shaping block 4, it becomes a pulse train waveform according to the information, and is further converted into an impulse waveform by the PLL circuit block 6, and the pulse train waveform corresponding to the clock frequency is output by the output of the synchronization detection circuit block 7. Is input to the digital signal processing circuit block 8. This clock frequency is determined in the case of a compact disc, and specifically, is 4.3218 MHz,
F1 Hz for convenience of explanation.

The information digitally processed by the digital signal processing circuit block 8 is temporarily stored in the RAM block 9, and then the information is read out at a clock frequency corresponding to the crystal oscillator in the digital signal processing circuit block 8.
The signal is input to the D / A converter circuit block 10 and converted into an analog waveform, which appears as an output terminal as a left (L) channel signal and a right (R) channel signal.

At this time, the capacity of the RAM block 9 is usually 16k bits, and information flows in and out at a considerable speed. That is, the information is temporarily stored in the RAM block 9,
Read immediately thereafter. This contributes to reducing the time delay from the time when the optical pickup 3 reads the information on the disk 2 to the output of the analog signal, that is, the reduction of the extension time.

Recently, there is a device that reproduces the data by slightly changing the clock frequency f1. Now, assuming that the clock frequency change is Δf1 and the clock frequency is (f1 + Δf1) Hz, the reading speed of information from the disk 2 is also changed at a rate corresponding to the change. The sampling frequency when converting the signal into an analog signal is also changed. Then, the rhythm pitch of the output can be changed as compared with that of the normal output. If the ratio is ΔP, the value is derived by the following equation.

Discos and the like have been used in such a compact disc player to perform continuous performance without being aware of a change in the rhythm pitch of information on a disc which is read and output next. This will be described below.

FIG. 8 shows the connection of a conventional continuous performance system. 101 and 102 are compact disc players (hereinafter C
A and B are shown, and slide switches 101a and 102a are provided on the front surface thereof. When the slide switches 101a and 102a move, the output of each of the CD players A101 and B102 according to the principle described above. The rhythm pitch can be changed. 103 is a mixer, C
It plays a role of mixing the output signals of the D players A101 and B102, and is further configured so that output levels from the mixers 103 of the respective CD players A101 and B102 can be varied by the adjusters 103a and 103b provided in the mixer 103. Have been.

104 is a monitor headphone, which is a CD player A101,
The mixed output of B102 can be heard regardless of the adjusters 103A and 103B.

The output of the mixer 103 is input to an amplifier 105, and the amplified signal is converted into an acoustic signal by a speaker 106, and emits a sound wave into space.

The operation of the conventional continuous performance system configured as described above will be described with reference to FIG.

FIG. 9A shows the output from the CD player A101, and the horizontal axis is the time axis. Generally, a single compact disc contains a plurality of songs (information).
Considering the read / playback of only a tune, the read / playback of the CD player A101 is set as the first tune.

In the figure, a1 is the rhythm pitch of the first music piece. 1
During the output of the song, the second song is played on the CD player B102, and while listening to the mixed sound of the output of the first and second songs on the headphones 104, the slide switch 102A is moved in accordance with the rhythm pitch a1 of the first song. The rhythm pitch of the second music is changed to be equal to or substantially equal to the rhythm pitch. Then, the output of the first music ends at time “t4”.

FIG. 9B shows the output of the CD player B102.
The output of the second music starts at time “t5”. a2 is the rhythm pitch of the output of the second music, and as described above, the rhythm pitch a2
Is changed so as to be equal to or substantially equal to the rhythm pitch a1 of the output of the first music.

FIG. 9 (c) shows the continuous output of the first and second music pieces. At the time of outputting the first music, the output is only from the CD player A101, and the information of the first music is sent to the amplifier 105 by the adjustment of the adjuster 103a of the mixer 103, and further converted into an audio signal by the speaker 106.

Next, when the time reaches “t4”, the output of the first music piece ends, so that the output of the CD player B102 is started. The time “t5” is performed at substantially the same time as the “t4”. Then 1
When shifting from the output of the song to the output of the second song, the rhythm pitch a1 of the first song is the same or almost the same as the rhythm pitch a2 of the second song, so you will notice a change in the rhythm pitch of the output of the second song You can jump to the second song without any problem.

Problems to be Solved by the Invention In such a conventional configuration, the operation of changing the rhythm pitch of the next second song based on the rhythm pitch of the output of the first song is actually performed by a human. By changing the rhythm pitch of the second song during the slight output period of the first song,
It is very difficult to adjust the rhythm pitch of the song and the end of the output of the first song and the start of the output of the second song at the same time. It was a great physical and mental burden for the person performing the operation.

In addition, two CD players as playback devices and a mixer are required, so that there is a problem that the scale becomes large for enjoying at home.

The present invention solves the above-mentioned problems. One CD player can automatically and continuously output the information output of the nth information and the information output of the (n + 1) th music without interruption. It is an object of the present invention to provide an information reproducing apparatus that does not notice a change.

Means for Solving the Problems In order to achieve the above object, the present invention provides a variable speed reading unit for reading information from a recording medium on which a plurality of information blocks are recorded, a storage unit for output information of the reading unit, and a system operation. And a rhythm control means operative to adjust the rhythm pitch of the succeeding second information block to the rhythm pitch of the first information block being reproduced. The information is read out faster and written to the storage means, the storage means is arranged to always read out the stored information at a specified speed, and the rhythm control device is provided with a rhythm pitch detection section for detecting an output rhythm pitch of the reading device. Rhythm pitch storage unit for storing the rhythm pitch
A rhythm pitch comparing unit that compares the rhythm pitch of the second information with the rhythm pitch of the second information, and operates to match the rhythm pitch of the second information with the rhythm pitch of the first information; It includes a rhythm pitch control unit for writing or supplying to the next-stage constituent means.

According to the present invention, the information reading means reads the information faster than the specified speed for a predetermined period after the start of reading and writes the information into the storage means, the storage means reads the stored information at the specified speed, and the rhythm control means Since the operation is performed so that the rhythm pitch of the succeeding information is adjusted to the rhythm pitch of the current reproduction information, a change in the rhythm pitch of continuous two information is not noticed, and smooth continuous reproduction of the two information can be performed. .

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of a compact disc player of an information reproducing apparatus according to a first embodiment of the present invention. Components that are functionally equivalent to the conventional example are denoted by the same reference numerals, and description thereof is omitted.

What is different from the conventional example is the CPU system control 14,
These are a servo signal processing block 15, a PLL circuit block 16, an information storage device 17, a digital signal processing circuit block 18, a rhythm control device 19, and the like.

 First, the reproduction of the first music will be described.

Now, assume that the first music piece is a reproduction of a certain music piece on the first disc. The normal playback state depends on the reading speed from the disk 2 and
Although the speed of the data input to the D / A converter 10 is the same, in this embodiment, the reading is performed at a higher speed than a predetermined reading speed for a certain predetermined period, and the reading speed is written to the information storage device 17; Reading from 17 is performed at a predetermined speed. Here, the predetermined speed is not necessarily limited because the rhythm pitch of the first tune is not always reproduced at the specified reproduction speed.

The temporal change of the numerical values of these components is shown in FIG.
(B) and (c) show. FIG. 2A shows a temporal change in the storage amount of the information storage device 17 in this embodiment. N ₂ represents the maximum value that the information storage device 17 can be a memory, this amount is the amount of information of several tens of seconds.

Time "0" is a disk playback start time, the storage amount of the information storage device 17 is already the N _1. actually,
From the disk playback start, until the amount of information of N ₁ to the information storage device 17 is a memory, it takes slightly longer, almost instantaneous as, here omit this time. Also N ₁
Is the minimum amount until the stored information is read.

Next, until time “t1”, a much larger amount of information than the amount of information read from the information storage device 17 is stored on the disk 2.
Since the data is read from the memory and stored, the amount of information stored in the information storage device 17 increases with time, and the time “t1”
The storage amount reaches the N _2.

After the time “t1”, the disk 2 drops to the prescribed number of revolutions, so that the amount of information written to the information storage device 17 and the amount of information read from the information storage device 17 become equal. Therefore, from the time "t1" to "t2", as the memory capacity of the information storage device 17 to maintain the left N _2.

At time “t2”, the reproduction of the disk 2 ends, and the disk information is no longer read. Therefore, after this time, only the information amount stored in the information storage device 17 is read. Therefore, the storage amount of the information storage device 17 decreases with time and becomes “0” at time “t3”. That is, the output time ends at “t3”.

FIG. 2B shows a temporal change of the clock frequency of the PLL circuit block 16. As described above, when the disk 2 is reproduced, the rotation frequency is higher than the specified value from time “0” to “t1”, and accordingly, the clock frequency is set to “f”.
2 ", and further, from time" t1 "to" t2 ", the rotation frequency of the disk 2 becomes the specified value, and the clock frequency becomes" f1 ".

FIG. 2C shows a temporal change in the linear velocity of the disk 2 at the position of the optical pickup 3 during reproduction of the disk 2. From time “0” to “t1”, the linear speed is S2 since the rotation speed of the disk 2 is higher than the specified value, and further, from time “t1” to “t2”, the linear speed is set to the specified value. Therefore, the linear velocity becomes S1.

With the above configuration, the rotation speed of the disk 2 is made higher than the specified value from the disk reproduction start time of the first music to the predetermined time “t1”, and the information read during that time is stored in the information storage device 17. Since the data output of the information storage device 17 is at a predetermined speed, the disk reading end time “t2” and the output end time “t3”
(See, for example, Japanese Patent Application No.
170201).

Next, a method of controlling the rhythm pitch will be described. FIG.
Represents a rhythm control device 19, inputs reproduced information, a rhythm pitch detection unit 20 that detects a rhythm pitch from the input information, a rhythm pitch storage unit 21 that stores the detected rhythm pitch, The rhythm pitch comparison unit 22 compares the rhythm pitch with the rhythm pitch of the previously written information stored in the rhythm pitch storage unit 21. According to the result compared by the rhythm pitch comparison unit 22, the rhythm of the previous information is obtained. A rhythm pitch control unit 24 that changes the clock frequency so as to substantially match the pitch is provided.

In the case of the information of the first music, since it is the first, the rhythm pitch detection unit 20 simply detects the rhythm pitch and stores it in the rhythm pitch storage unit 21.

The detection of the rhythm pitch of the first song is performed during the reproduction of the first song.
The control for adjusting to the music and the operation of generating a continuous output are as follows.

FIG. 4 shows the signal flow. FIG. 4A shows a flow of information of the first music. For convenience of explanation, the information storage device 17 is shown as a memory A and a memory B. As described above, the information of the first music piece is read quickly for a predetermined time, so that the storage amount of the memory A increases. Since the reading speed is the specified speed, the data of the first music is read out by the clock A, amplified, and then converted in the D / A converter block 10.

During this time, the rhythm pitch of the first tune is detected by the rhythm pitch detection unit 20 and stored in the rhythm pitch storage unit 21.
FIG. 4 (b) shows the state after the disk reading of the first music has been completed, and the output of the first music is performed based on the information stored in the memory A.

After reading the first song, the disc is replaced with a second song and the second song is immediately read. Then, as shown in FIG. 3, the rhythm pitch of the information of the second tune read is detected by the rhythm pitch detection unit 20, and the rhythm pitch of the output of the first tune stored in the rhythm pitch storage unit 21 is compared with the rhythm pitch. The pitch comparison unit 22 controls the rhythm pitch control unit 23 so that the rhythm pitch of the second tune substantially matches the rhythm pitch of the first tune.

Then, the clock frequency is changed so that the rhythm pitch becomes almost the same as that of the first tune. This is clock B. As shown in FIG. 4 (c), the information of the second music read from the disk 2 is written to the memory B, and the output of the information of the first music from the memory A is completed at the same time as the information of the second music is read from the memory B. Is read. With the above operation, the sound output can be made continuous without changing the rhythm pitch.

FIG. 5 shows the output in this embodiment. Until now, the first and second songs have been described for convenience of explanation. However, since any number of songs can be generally continued, the continuous output of the nth and (n + 1) songs is shown. b ₁ is the rhythm pitch of the information of the n-th song,
There is no problem if it is a normal rhythm pitch, or it can be changed or a rhythm pitch. The time “t6” is the output end time of the n pieces of music, and the output start time “t7” of the (n + 1) piece of music can be performed at approximately the same time by control. And the rhythm pitch b ₂ of the (n + 1) tune is
rhythm down pitch b ₁ of n tracks are those that changed to substantially coincide Thus, from n tracks (n +
1) The output to the music continues smoothly.

In addition, by using the information storage device 17, one CD
Since it can be performed by the player, continuous output of information within the same disk becomes possible, which was conventionally impossible with one disk.

Second Embodiment Next, a second embodiment will be described. FIG. 6A is a block diagram showing a signal flow in the second embodiment. The configuration is almost the same as that of the first embodiment, except for the differences.
The amplifiers 24 and 25 in FIG. 6 (a) are that the gain can be changed with time under the control of the CPU system control 14, and that the timing of the clock A and the timing of the clock B are controlled.

FIG. 11A shows a state in which information immediately before the output of the nth music and the information immediately after the start of the (n + 1) th music are mixed and output with good timing. This will be described with reference to FIG. rhythm pitch of the output of the n song information is a b _1, just before the end of the time of the output of the n song "t
8 ", the gain of the amplifier 24 is gradually reduced to zero at time" t10 ". The (n + 1) th music is set to be equal to the rhythm pitch of the nth music, and its start time is set to" t9 ". From this time, the gain of the amplifier 25 is gradually increased.
This time “t9” is set to the start time of the rhythm of the output of the nth music. Then, the output level of the sound of the n-th song decreases near the end, and (n + 1)
Since the output of the music piece starts, the connection between the continuous output of the n-th music piece and the (n + 1) -th music piece can be made smoother than in the first embodiment.

Thus, according to the information reproducing apparatus of the embodiment of the present invention,
A buffer memory means for setting the information writing speed faster than a specified speed and a reading speed a specified speed for a predetermined time from the start of disk reproduction and a rhythm pitch control means for output information are provided. The information can be made continuous with the rhythm pitch substantially matched. In the case of the second embodiment, since a variable gain amplifier is provided in addition to the above, fade-in / out can be performed well.

Although a compact disc player was used as an information reproducing apparatus, this principle holds true for all digital signal data.
It goes without saying that the same effect can be obtained by performing A / D conversion and putting the data into this device.

Further, even if the information of the n-th disc is not read from the beginning, the reading is started from a predetermined time by programming, or at a predetermined time,
Similar effects can be obtained even when reading is completed.

Effect of the Invention As described above, the present invention provides a configuration in which the reading time from the disc for a predetermined time is made faster than a predetermined reading, the portion is stored in an information storage device, and the reading is performed at a predetermined speed, And a rhythm pitch control device for detecting, storing, comparing and controlling the rhythm pitch of the nth tune.
+1) Control to change the rhythm pitch of the tune to be the same or substantially the same between the reading end time and the output ending time of the n tune, and to start the next output immediately after the output of the n tune is completed. The information reproducing apparatus can generate a continuous output without noticing the change in the rhythm pitch.

[Brief description of the drawings]

FIG. 1 is a block diagram of a compact disc player of an information reproducing apparatus according to a first embodiment of the present invention.
(B) and (c) respectively show the storage capacity of the information storage device,
FIG. 3 is an explanatory view of a temporal change of a clock frequency and a linear velocity of a disk, FIG. 3 is a block diagram of the rhythm control device, FIG.
FIG. 5 is a block diagram showing a signal flow in the device, and FIG.
FIGS. 6 (a) and 6 (b) are block diagrams and output explanatory diagrams showing signal flows in a second embodiment of the present invention, respectively, and FIG. 7 is a conventional compact disk player. FIG. 8 is a connection diagram of a conventional compact disk player continuous output system, and FIG. 9 is an explanatory diagram of an output of a conventional compact disk player. 2 ... Disc, 3 ... Optical pickup, 14 ... CPU system control, 15 ... Servo signal processing, 16 ... PL
L, 17: Information storage device, 18: Digital signal processing block, 19: Rhythm control device.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-128360 (JP, A) JP-A-3-62359 (JP, A) JP-A-3-1444961 (JP, A) 60286 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) G11B 19/00-19/02 G11B 20/10

Claims (3)

(57) [Claims] 1. A variable speed reading means for reading information from a recording medium on which a plurality of information blocks are recorded, a storage means for storing output information of the reading means, a system operation control means, and a subsequent second information block Rhythm control means that acts to match the rhythm pitch of the first information block being reproduced with the rhythm pitch of the first information block being reproduced. The control reading means reads information faster than a prescribed speed for a predetermined period after the start of reading, and stores the information in the storage means. Writing and the storage means are arranged to always read out stored information at a specified speed; the rhythm control device is a rhythm pitch detection unit for detecting an output rhythm pitch of the reading device; a rhythm pitch for storing the detected rhythm pitch A storage unit for comparing a rhythm pitch of the first information with a rhythm pitch of the second information; An information reproducing device including a comparing portion, a rhythm pitch controlling portion that operates to match the rhythm pitch of the second information with the rhythm pitch of the first information and writes the information into the information storage means or supplies the information to the next-stage constituent means; apparatus. 2. A variable speed reading means for reading information from a recording medium on which a plurality of information blocks are recorded, a storage means for storing output information of the reading means, a system operation control means, and a subsequent second information block Rhythm control means for operating the rhythm pitch of the first information block being reproduced to match the rhythm pitch of the first information block being reproduced. The control reading means reads information faster than a prescribed speed for a predetermined period after the start of reading and writes the information into the storage means. , The storage means is arranged to always read out the stored information at a prescribed speed, and the control means of the system operation, after the end of the first information,
The information reproducing apparatus according to claim 1, wherein control is performed to immediately start outputting the second information. 3. A system according to claim 1, further comprising a fade-in means for fading in the first information output and a fade-out means for the second information output.
Or the information reproducing apparatus according to (2).