JPH0668493A - Fast-forwarding playback device - Google Patents

Abstract

PURPOSE:To perform fast-forwarding playback operation by fixed-speed rotation as it is by finding the number of jumped tracks and an increment in playback address after the jump by a controller, and repeating specific operation in order according to the calculated values. CONSTITUTION:Image data are recorded on tracks 1 of a disk 2 in address order while a specific number of sectors is put in one unit, screen by screen. The light from a laser diode 20 is passed through a half-mirror 21 and a lens 3 to form an extremely small spot on the track surfaces and its reflected light is made incident on a 4-split detector 22. Its total amount is sent to the controller 15 through an RF amplifier 5, a demodulating circuit 6, and an address extracting circuit 7. The controller performs specific arithmetic and outputs the result to a data extracting circuit 8 to reproduce data of one screen, then sends its output to a lens driving circuit 11 and a slider motor driving circuit 12 to make a jump, and then repeating the one-screen reproduction thereafter. The magnification of the fast-forwarding playback operation is varied and set corresponding to the number of jumped tracks, so the fast-forwarding playback operation can be performed by the constant rotation at all times without varying the rotating speed of the disk.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fast-forward reproducing device, and more particularly to a fast-forward reproducing device for a disc on which image data is recorded.

[0002]

2. Description of the Related Art In recent years, attempts have been vigorously made to record image data on a disk medium by making use of random access performance, and in particular, the technology for recording data on an optical disk has been remarkably developed and its products have already been marketed. It is provided. Therefore, in general, an optical disc for recording NTSC image data has address parts 1501 to 1509 as shown in FIG.
To 1509, the address information is set in order from 1501 to 150.
It is recorded as 2,1503 ....

Reference numeral 1510 is a track, and 1511 is a light spot. The light spot 1511 is narrowed down to a minute diameter by an optical head using a known technique, and the track 151
It is irradiated on the optical disc 0 and is scanned in the arrow direction based on the rotation of the optical disc 1500. In addition, in the NTSC system, one screen is 1 /
30 seconds, and one screen is composed of two unit screens (fields). In the data area located between the addresses 1501 and 1502 on the optical disc 1500, the first unit screen (first field) of the first screen is displayed. ) Is recorded, and the second unit screen (second field) of the first screen is recorded in the data area located between the addresses 1502 and 1503.
By rotating one by one, it is possible to reproduce one screen at a time, that is, 1/30 seconds.

The conventional fast-forwarding device has a track 1606 forming a continuous spiral as shown in FIG.
An optical disc 1605 having a disc, a disc motor 1619 for driving the disc 1605, and a pickup 16
01, a reading means 1620 having an address extraction circuit 1610 including the pickup 1601, a tracking means 1621 for tracking the reading means 1620, and a controller 1612 for controlling the drive of the disk motor 1619. The controller 1612 controls the disk motor 1619 based on the signal input from the address extraction circuit 1610, changes the rotation speed of the disk motor 1619, and, for example, changes 1800 rotations per minute to 3600 rotations per minute. It is designed to realize double-speed fast-forward playback.

[0005]

However, in the above-described conventional fast-forward reproduction configuration, it is necessary to increase the rotational speed of the disk motor in proportion to the magnification of the fast-forward reproduction. However, the speed increase in a normal motor is limited to about double speed, and a large-capacity motor must be used in order to stably obtain a higher speed rotation, which naturally increases the cost. In the case of fast-forward reproduction, the optical disc rotates at a high speed, the eccentric acceleration of tracks on the disc increases, and it becomes difficult to stabilize the tracking servo.

The present invention has been proposed in view of the above problems, and an object thereof is to realize fast-forward reproduction while maintaining a constant rotation speed without changing the rotation speed of a disk, thereby changing the rotation speed. It is an object of the present invention to provide a fast-forward playback device that can solve the problems that occur.

[0007]

The present invention achieves the above object.
Therefore, the sectors consisting of the address part and the data part are consecutive.
It has a track that forms a spiral
Image data is in units of a predetermined number of sectors required for one screen.
Discs recorded in the order of address and recorded
Reading means for reading the address information and the data information,
Tracker that tracks the reading means on the rack
The jumping means and the reading means between the tracks.
From the jumping means and the reading means
Data reproducing means for reproducing data information by the output signal of
And a controller, and the controller
Is the number of track jumping lines adapted to the rapid traverse ratio
The playback start address after track jumping.
The amount of increment is calculated and calculated from the playback start address.
It is necessary to play the
The first operation of outputting a signal to the data reproducing means,
Jump jumping for the number of readings
Second operation to output a signal to the jumping means so that
And the playback start address for the calculated increment
And a third action for incrementing
It is characterized in that it is repeated in the order of the third action.
In this case, the controller is forward forwarding
Number of sectors that make up one track
s, the number of sectors nf for recording one screen of data, and fast forwarding
A positive integer that satisfies (Equation 9) and (Equation 10) from the multiplication factor x
nj ₁And m₁And calculate the number of track jumping
nj₁And increment of the playback start address after jumping
Ment amount m₁* Nf is calculated and backward fast forward
In the case of, a positive integer n that satisfies (Equation 11) and (Equation 12)
j₂And m₂And calculate the number of track jumping n
j₂And increment of the playback start address after jumping
Amount m₂It is desirable to calculate * nf and
Yes.

[0008]

[Equation 9]

[0009]

[Equation 10]

[0010]

[Equation 11]

[0011]

[Equation 12]

If one screen is composed of a plurality of unit screens,
In the case of forward fast forward,
The number of sectors S that make up one track of the track and the screen
Number of sectors to record data nf and 1 unit screen
From the number of sectors mf and the rapid feed rate x, (Equation 13) and (Equation)
Positive integer nj that satisfies 14)₃And m₃And calculate the tiger
Number of jump jumping nj₃Playback after jumping with
Start address increment amount m₃Calculate * nf
In addition, in the case of backward fast forward, (Equation 15) and (Equation 1)
Positive integer nj that satisfies 6)_FourAnd m _FourAnd calculate
Number of jumping nj_FourAnd start playing after jumping
Address increment amount m_Four* Nf is calculated
You can do it.

[0013]

[Equation 13]

[0014]

[Equation 14]

[0015]

[Equation 15]

[0016]

[Equation 16]

[0017]

According to the above configuration, the controller calculates the number of track jumps and the increment amount of the reproduction start address after jumping, and repeats the first, second and third operations in order based on the calculated value. By doing so, the magnification of the fast-forwarding reproduction is changed and set according to the number of track jumping lines, so that the fast-forwarding reproduction can be realized while keeping the constant rotation without changing the rotation speed of the disc.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A fast-forward reproducing apparatus of the present invention will be described based on the embodiments of the drawings. FIG. 1 is a block diagram of an embodiment of the present invention. In this embodiment, as shown in FIG. 1, a disk-shaped disc 2 having a track 1 forming a spiral in which sectors composed of an address portion and a data portion are continuous, and an objective lens 3 is faced to the track 1 of the disc 2. A read means 9 for reading address and data information, which includes the picked-up pickup 4, the pickup 4, the RF amplifier 5, the demodulation circuit 6, the address extraction circuit 7, and the data extraction circuit 8.
And pickup 4 and tracking error generation circuit 1
1, a slider motor drive circuit 12 and a slider motor 13, and a tracking means 14 for controlling the irradiation of the spot light to an appropriate position, and an output of the controller 15 through the slider motor drive circuit 12 to drive the slider motor 13
Driving means to move the reading means 9 in the radial direction of the disk 2 to jump between the tracks 1, a reproducing means 18 including a video section 17 for reproducing the extracted data information, and an address extracting circuit 7. And a controller 15 that operates by receiving an information signal from the controller.

On the track 1 of the disk 2, image data of a plurality of screens are recorded by arranging the predetermined number of sectors as one unit for each screen in the order of addresses. The pickup 4 includes an objective lens 3, an objective lens driving coil 19 that drives the lens 3 in a small amount, a laser diode 20, and a half mirror that reflects the light beam from the laser diode 20 and transmits the light beam from the objective lens 3. 21 and a four-divided detector 22, and the laser diode 2
A light beam emitted from 0 is reflected by the half mirror 21, is narrowed down to a minute diameter by the objective lens 3, and irradiates the track 1 surface facing the objective lens 3 as spot light.
The reflected light from the surface of the track 1 is transmitted through the half mirror 21 through the objective lens 3 and is incident on the four-divided detector 22.

The four-division detector 22 divides incident light into four.
The signal is divided, the total amount is converted into an electric RF signal as a total output, and the electric RF signal is supplied to the demodulation circuit 6 via the RF amplifier 5.
The demodulated signal is supplied to the address extraction circuit 7 and the data extraction circuit 8. The address extraction circuit 7 supplies the input signal supplied from the demodulation circuit 6 to the controller 15 as an address information signal.

Further, the data extraction circuit 8 extracts the data information only when the reproduction signal is output from the controller 15 by the operation of the controller 15 which receives the address information signal, and the video section 17 as the reproduction means 18 is provided. It is designed to be supplied to. The video section 17 makes an image based on the data information from the data extraction circuit 8 and, when the data information from the data extraction circuit 8 is stopped, the information immediately before the stop is stored in a memory and the information is displayed as an image. Is made to do.

The output of the 4-division detector 22 is also supplied to the tracking error generation circuit 10. The tracking error generation circuit 10 uses, for example, a one-beam method such as a push-pull method or a heterodyne method, or a three-beam method.
A tracking error signal generation method such as a beam method is used, and the objective lens drive circuit 1 is generated by the tracking error signal output from the tracking error generation circuit 10.
The objective lens 3 is driven by the objective lens drive coil 19 via 1 to track the light spot to an appropriate position on the track 1.

The slider motor 13 is driven and controlled by a slider motor drive circuit 12. That is, the position of the objective lens 3 is detected based on the output from the objective lens drive circuit 11, and the slider motor 13 is driven so that the position of the objective lens 3 becomes the neutral position to move the pickup 4 in the radial direction of the disk 2. It is designed to be moved to the position for position control.

The objective lens drive circuit 11 and the slider motor drive circuit 12 are also driven and controlled by an output signal from the controller 15. That is, a drive signal is output to the slider motor drive circuit 12 based on the signal from the address extraction circuit 7 to drive the slider motor 13, and the reading means 9 is track jumped on the track 1.

Next, regarding the operation of the first embodiment configured as described above, the case of fast forward reproduction in the forward direction will be described with reference to FIG.
3 will be described with reference to the sequence diagram of FIG. In FIG. 2, the optical disk 2 has addresses 202 to 216 on the track 1, and the addresses increase from the outer circumference to the inner circumference of the disk 2.

The image data is recorded by arranging it in the order of addresses in units of a predetermined number of sectors required for one screen.
Specifically, the sectors are recorded in order of time from a sector having a small address to a sector having a large address. It is assumed that the number of sectors of one round of the optical disc 2 is s, and the number of sectors forming one screen is nf, and the arrow indicates the movement of the light spot during fast-forward reproduction to seek the light spot to the track 1 having the start address. In the still state, the fast-forward reproduction start address ks, the fast-forward reproduction end address ke, and the fast-forward magnification x are set in the controller 15. (Step 1) In this case, the address is ks <ke.

According to the set (step 1), the controller 15 calculates the track jumping number nj ₁ and the coefficient, that is, the increment amount m ₁ of the reproduction start address after jumping. (Step 2) Specifically, nj ₁ and m ₁ satisfying the following two equations are calculated.

[0028]

[Equation 17]

[0029]

[Equation 18]

Then, the controller 15 sets the target address to ks. (Step 3) After that, the controller 15 determines whether or not the reproduction address ks, 202 read from the disc 2 is the end address ke 214 or more. (Step 4) As a result, since the reproduction address ks, 202 is smaller than the end address ke, 214, it is compared whether or not the reproduction address ks, 202 is equal to the target address. (Step 5) When the reproduction addresses ks and 202 are equal to the target address, nf sectors (arrows 218 and 219) (one screen)
A reproduction signal is output from the controller 15 to the data extraction circuit 8 so as to reproduce, and data is sent from the data extraction circuit 8 to the video section 17 based on the signal and reproduced to form a video.

After reproduction, the controller 15 stops the output of the reproduction signal to the data extraction circuit 8 and, at the sector following the address 204, performs nj ₁ track jumping toward the inner peripheral side as indicated by an arrow 220. ,
A drive signal is output to the objective lens drive circuit 11 and the slider motor drive circuit 12 to cause the light spot, that is, the reading means 9 to perform track jumping. (Step 8) After that, the controller 15 resets the target address to the target address + m ₁ * nf. (Step 9) Then, the reproduction address 211 is again set to the end address 214,
It is determined whether it is ke or more. (Step 4) In this case, the reproduction address 211 is the end address 214,
Since it is located on the outer peripheral side of track 1 with respect to ke and is smaller than the end address 214 and ke, this reproduction address 21
Compare whether 1 is equal to the target address. (Step 5) As a result, the reproduction address 211 becomes the target address ke +
Since it is not equal to m ₁ * nf, 212, it waits for the next address. (Step 6) Then, each step (Step 4), (Step 5)
While repeating the above, the process proceeds as shown by an arrow 222 to reach the target address ke + m ₁ * nf, 212.

Here, the controller 15 determines again whether the target address ke + m ₁ * nf, 212 is not less than the end address ke, and (step 4) the address 21.
Compare whether 2 is equal to the target address ks + m ₁ * nf. (Step 5) If the addresses ks + m ₁ * nf and 212 are equal to the target address ks + m ₁ * nf, the data extraction circuit 8 reproduces nf sectors as indicated by arrow 223.
A reproduction signal to the video section 1 from the data extraction circuit 8.
Data is sent to 7 and reproduced to form a video. (Step 7) After this reproduction, the controller 15 sends the address ks +
In the sector following (m ₁ +1) nf 213, arrow 22
As shown in FIG. 4, a driving signal is output to the objective lens driving circuit 11 and the slider motor driving circuit 12 so as to perform nj ₁ track jumping toward the inner peripheral side, and the reading means 9 is track jumped. (Step 8) Thereafter, reproduction and jumping are repeated in the same manner, and the arrow 22
While performing track jumping as shown in 5, it is judged whether the address ke + s + 1, 216 is the end address ke or more. (Step 4) If the address ke + s + 1, 216 is the end address ke or more as shown in FIG. And (Step 10) In the above flow, after reproducing the screen of the sector starting from the address ks, 202 (hereinafter referred to as screen A), the screen of the sector starting from the address ks + m ₁ * nf, 212 (hereinafter referred to as screen B) ) Play.

In the normal reproduction, however, it takes a time of m ₁ * nf sectors to start from the screen A and reach the screen B. However, in the fast-forward reproduction means of this embodiment,
Time and the expiration of sectors nf number of screens A, m ₁ * nf from the address _{ks + nf + s * nj 1} , 210 after jumping to the address ks + m ₁ * nf, 212
-Nf-s * nj Sum of ₁ sector over time, ie m ₁ *
nf-s * nj The time required to pass ₁ sector is sufficient.

Therefore, the magnification of the fast-forward reproduction in this case is given by the following equation.

[0035]

[Formula 19]

Therefore, by substituting nj ₁ of (Equation 17) into (Equation 19),

[0037]

[Equation 20]

Then, the value of the magnification becomes x, and the fast forward reproduction of x times in the forward direction can be realized as set. Next, the case of fast-forward reproduction in the reverse direction will be described based on the flowchart of FIG. 5 with reference to the sequence diagram of FIG.

In FIG. 4, the optical disc 2 has a track 1
As shown in FIG. 2 (forward direction), the addresses 402 to 413 are provided on the top, and the addresses increase from the outer circumference to the inner circumference of the optical disc 2, and the image data is addressed in units of a predetermined number of sectors required for one screen. It is recorded side by side. Specifically, the sectors are recorded in order of time from a sector having a small address to a sector having a large address.

Assuming that the number of sectors for one rotation on the optical disc 2 is s and the number of sectors for forming one screen is nf, the arrow indicates the movement of the light spot during fast-forward reproduction, and seeks the light spot to the track 1 having the start address. Then, in the state of still shooting, the fast forward start address ks, 402,
The end addresses ke and 411 and the fast-forward reproduction magnification x are set in the controller 15. (Step 1) In this case, ks> ke.

From the set (step 1), the controller 15 calculates the track jumping number nj ₂ and the coefficient, that is, the increment amount m ₂ of the reproduction start address ks after jumping. (Step 2) Specifically, nj ₂ and m ₂ satisfying the following two expressions are calculated.

[0042]

[Equation 21]

[0043]

[Equation 22]

Then, the controller 15 sets the target address to ks. (Step 3) After that, the controller 15 determines that the reproduction address ks, 402 read from the optical disc 2 is the end address ke, 41.
Judge whether it is 1 or less. (Step 4) As a result, the reproduction address ks, 402 is the end address k.
e, the reproduction address ks, 402
Is equal to the target address ke. (Step 5) When the reproduction addresses ks and 402 are equal to the target address ke, nf sectors (1
A reproduction signal is output from the controller 15 to the data extraction circuit 8 so as to reproduce the (screen), and the data is sent from the data extraction circuit 8 to the video section 17 by the reproduction signal to be reproduced as an image. (Step 7) The post-reproduction controller 15 stops the output of the reproduction signal to the data extraction circuit 8 and nj toward the outer peripheral side in the sector following the address 404 as indicated by an arrow 417.
_A drive signal is output to the objective lens drive circuit 11 and the slider motor drive circuit 12 so as to perform _two track jumping to cause the light spot, that is, the reading means 9 to be track jumped (step 8). Then, the controller 15 sets the target address. Reset to target address -m ₂ * nf. (Step 9) Then, the reproduction address 407 is again set to the end address ke, 4
It is determined whether it is 11 or less. (Step 5) Since the reproduction address 407 is located on the inner circumference side of the end addresses ke and 411 and is larger than the end addresses ke and 411, this address 407 is the target address ks-m _2.
* Nf is compared with 408 for equality. (Step 5) As a result, the address 407 becomes the target address ks-m.
₂ * nf, not equal to 408, so wait for next address. (Step 6) Then, the above steps (Step 4) and (Step 5) are repeated to proceed as shown by an arrow 419 to reach the address ks-m ₂ * nf, 408.

Here, the controller 15 returns to the address k again.
It is determined whether s-m ₂ * nf, 408 is less than or equal to the end address ke, and (step 4) the address ks-
m ₂ * nf, 408 is the target address ks-m ₂ * nf,
The result is compared with 408. (Step 5) If the comparison results are the same, n as indicated by arrow 420
A reproduction signal is output to the data extraction circuit 8 so as to reproduce f sectors (one screen), and data is sent from the data extraction circuit 8 to the video section 17 to be reproduced as a video. (Step 7) The post-reproduction controller 15 causes the reading means 9 to perform nj ₂ track jumping toward the outer peripheral side as indicated by an arrow 421 in the sector following the address 409, and the objective lens drive circuit 11 and A drive signal is output to the slider motor drive circuit 12 to cause track jumping. (Step 8) After that, reproduction and jumping are repeated in the same manner, and the arrow 4
Address k while jumping like 22
It is determined whether e−s + 1, 413 is less than or equal to the end address ke, and the addresses ke−s + 1, 413 are determined as shown in FIG.
If is less than or equal to the end address ke, the reproduction is ended. (Step 10) In the above flow, after reproducing the screen of the sector starting from the addresses ks and 402 (hereinafter referred to as screen C), the screen of the sector starting from the address ks-m ₂ * nf (hereinafter referred to as screen D) ) Play.

In this case, in normal reproduction, a time of m ₂ * nf sectors from the screen C to the screen D is required, but in the fast-forward reproduction of this embodiment, the sector nf of the screen C is required. The time elapsed after passing the number and the address ks + nf−s * nj ₂ after jumping, 406 to s * nj ₂ −nf− from address ks−m ₂ * nf, 408.
s * nj Sum of times elapsed in ₂ sectors, that is, s * n
The elapsed time of j ₂ −m ₂ * nf sectors is sufficient.

Therefore, the magnification of the fast-forward reproduction in this case is given by the following equation.

[0048]

[Equation 23]

Substituting nj ₂ of (Equation 21) into (Equation 23),

[0050]

[Equation 24]

As a result, the value of the magnification becomes x, and the fast-forward reproduction of x times in the reverse direction can be realized as set. A more specific example of the operation during the fast-forward reproduction described above will be described with reference to the sequence diagrams of FIGS. 6 and 7. First, FIG. 6 shows the fast forward in the forward direction, and 2 is an optical disc.
Address portions 601 to 630 are 1, 2, 3, ...
・ Addresses are recorded in order. 1 is a truck. In the optical disc 2, it is assumed that the number of sectors in one round is 4, that is, s = 4, and the number of sectors that make up one screen is 4, that is, nf = 4. Here, the number nj ₁ of track jumps and the coefficient m _{1 for} performing fast forward reproduction of 1.5 times in the forward direction are set as x = 1.5 from (Equation 17) and (Equation 18), and nj ₁ = 1 and m. ₁ = 3 is required.

Therefore, in the operation, if the reproduction start address is No. 1, the address 601 (No. 1) starts from the arrow 63.
After reproducing 3, 634, 635, 636 and 4 sectors (one screen), one track jumps to the inner circumference side as indicated by arrow 637, and the next target address is 1 + m ₁ * nf = 1
Since it is number 3, arrows 638, 639, 640, 641
Then, the program passes without being reproduced, and one screen is reproduced again from the address 613 (No. 13), and so on.

Here, after the screen reproduction following the address 601 (No. 1), the screen following the address 613 (No. 13) is reproduced, but in the normal reproduction, the elapsed time of 12 sectors corresponds to 8 sectors. Plays at the elapsed time, so 1.5
It is double fast-forward playback. Next, the operation during fast-forward reproduction in the reverse direction will be described with reference to the sequence diagram of FIG. 2 is an optical disc, 701 to 730 are address sections, 1,
Addresses are recorded in the order of 2, 3 ... 1 is a truck. In the optical disc 2, it is assumed that the number of sectors in one round is 4, that is, s = 4, and the number of sectors that make up one screen is 4, that is, nf = 4. Here, the number of track jumps nj ₂ and the coefficient m _{2 for} performing fast-forward reproduction of 1.5 times in the reverse direction are x = 1.5 (equation 21),
From (Equation 22), nj ₂ = 5 and m ₂ = 3 are obtained.

Therefore, if the reproduction start address is No. 25, the operation starts from the address 725 (No. 25) in the direction of arrow 7.
33, 734, 735, 736 and 4 sectors (1 screen)
After playing, the track jumps to the 5 outer circumference side as indicated by arrow 737, and the next target address is 25-m ₂ * nf.
₂ = No. 13, so arrows 738, 739, 740,
741 and passes through without being reproduced, and addresses 713 (13
It will be repeated from 1) to 1 screen again.

Here, the screen following address 725 (No. 25) is reproduced, and then the screen following address 713 (No. 13) is reproduced. Plays at the elapsed time, so 1.5
It is double fast-forward playback. As described above, according to the present embodiment, it is possible to perform fast-forward reproduction in the forward direction or the reverse direction without changing the rotation number and the rotation direction of the disc.

In the present embodiment, the controller calculates the track jumping number and the increment amount of the reproduction start address after the track jump according to the fast-forwarding factor. However, the fast-forwarding factor and the track jumping number, and ROM the correspondence table with the increment amount of the playback start address after jumping
It may be configured such that the correspondence table is recorded and the like is referred to.

Further, in the present embodiment, the address is sequentially increased from the outer circumference to the inner circumference, and the disk in which the image data is recorded in time order from the outer circumference to the inner circumference has been described. In the case of a disc in which image data increases in order from the outer circumference to the outer circumference, and the image data is recorded in time order from the inner circumference to the outer circumference, the jumping direction is set so that the forward direction is jumped to the outer circumference and the reverse direction is jumped to the inner circumference. You can change it.

Further, in the case of a disc in which the addresses increase in order from the outer circumference to the inner circumference, and the image data is recorded in time order from the inner circumference to the outer circumference, the method of reading the sign of the reproduction address in the opposite direction, etc. , So that the address to be read increases in order from the inner circumference to the outer circumference,
The jumping direction may be changed so that the forward direction jumps to the outer circumference and the reverse direction jumps to the inner circumference.

Further, in the case of a disc in which the addresses increase in order from the inner circumference to the outer circumference and the image data is recorded in time order from the outer circumference to the inner circumference, a method such as reading the sign of the reproduction address in the opposite direction is used. Then, the address to be read may be increased in order from the outer circumference to the inner circumference. Further, in this embodiment, one screen is reproduced, but a plurality of screens may be reproduced.

Next, a second embodiment of the present invention will be described. The main configuration and operation of the second embodiment are shown in FIG.
There is basically no difference from the first embodiment shown in FIG. Specifically, only the first operation of outputting to the reproducing means so as to reproduce the data based on the reproduction start address in the controller 15 is different.

That is, when one screen is composed of a plurality of unit screens, the controller 15 determines the number of sectors s constituting one round of the track 1, the number of sectors nf for recording data of one screen, and the number of sector of one unit screen. Number of sectors to record data mf
And the fast-forward ratio x, in the case of forward fast-forward playback,
The nj ₃ and m ₃ satisfying the equations (13) and (14) are calculated, and the number of track jumping nj ₃ and the increment amount m of the reproduction start address after jumping are calculated.
₃ * nf is calculated, and in the case of backward fast forward, nj ₄ and m ₄ satisfying the formulas (15) and (16) are calculated, and after jumping with the number of track jumping nj ₄ Increment of playback start address m ₄ *
nf and are calculated.

Here, the mathematical formulas involved in the latter part will be described first.

[0063]

[Equation 25]

[0064]

[Equation 26]

Then, as in the first embodiment, the magnification x in the fast forward reproduction is

[0066]

[Equation 27]

Substituting (Equation 25) into (Equation 27)

[0068]

[Equation 28]

Thus, x times fast forward reproduction can be realized in the forward direction as set. The mathematical expressions involved after this will be described first.

[0070]

[Equation 29]

[0071]

[Equation 30]

Further, the magnification x in the backward fast forward reproduction is

[0073]

[Equation 31]

By substituting (Equation 29) into (Equation 31),

[0075]

[Equation 32]

And fast forward x times in the reverse direction as set.
Playback can be realized. Fast-forward playback in the second embodiment
More specific example of the operation at the time of sequence diagram of FIGS. 8 and 9
Will be explained. FIG. 8 shows the forward direction. Two
Is an optical disc, and 1301 to 1330 are addresses.
Yes, the addresses are recorded in order of 1, 2, 3 ...
It 1 is a truck. One round on optical disc 2
The number of sectors is 4, that is, s = 4, and one screen is configured.
There are four sectors, that is, nf = 4, and one unit screen
The number of sectors to be configured is two, that is, mf = 2. here
A track jumper for double forward playback in the forward direction
Number np₃And coefficient m ₃Is x = 2 (Equation 25),
From (Equation 26), nj₃= 1, m₃= 2.

Therefore, in the operation, if the reproduction start address is No. 1, the address 1301 (No. 1) starts from the arrow 13
After reproducing 2 sectors (one unit screen worth) like 33 and 1334, one track jumps to the inner circumference side as shown by an arrow 1335, and the next target address is 1 + m ₃ * nf = 9.
Since it is No., it passes without being reproduced as indicated by arrows 1336 and 1337, and two sectors (one unit screen) are reproduced again from the address 1309 (No. 9).

Here, after the screen following the address 1301 (No. 1) is reproduced, the screen following the address 1309 (No. 9) is reproduced. Since it can be played in minutes elapsed time, it is a double fast-forward playback. Next, a more specific example of the operation during the reverse fast-forward reproduction will be described with reference to the sequence diagram of FIG. 2 is an optical disk. 14
Address portions 01 to 1430 are 1, 2, 3 ...
・ Addresses are recorded in order. 1 is a truck. In the optical disc 2, the number of sectors in one round is 4, that is, s = 4, the number of sectors that make up one screen is 4, that is, nf = 4, and the number of sectors that make up one unit screen is 2, that is, mf = Assume that it is 2. Here, the number of track jumps nj ₄ and the coefficient m for double-speed fast forward reproduction in the reverse direction.
_{From 4 (} ha), x = 2, (Equation 29) and (Equation 30),
j ₄ = 3 and m ₄ = 2.

Therefore, assuming that the reproduction start address is No. 25, first, from the address 1425 (No. 25), 2 sectors (for one unit screen) as indicated by arrows 1433 and 1434.
, And then three tracks are jumped to the outer peripheral side as indicated by arrow 1435, and the next target address is 25-m ₄ * n.
Since f ₄ = 17th, it passes without reproducing as shown by arrows 1436 and 1437, and the address 1417 (17th)
From this point onward, two sectors (one unit screen worth) are reproduced again, and so on.

Here, after the screen following the address 1425 (25th) is reproduced, the screen following the address 1417 (17th) is reproduced. However, in normal reproduction, an elapsed time of 8 sectors is required, whereas in 4 sectors Since it can be played in minutes elapsed time, it is a double fast-forward playback. Focusing on the number of jumping lines, in the case of fast forward in the first embodiment, (Equation 17) is substituted into (Equation 18) to obtain the following relational expression.

[0081]

[Expression 33]

From these (Equation 33) and (Equation 17), the following relational expression can be obtained from the number of jumping lines nj ₁ .

[0083]

[Equation 34]

On the other hand, in the case of fast forward in the second embodiment, (Equation 17) is substituted into (Equation 18) to obtain the following relational expression.

[0085]

[Equation 35]

From these (Equation 35) and (Equation 25), the following relational expression is obtained by the number of jumping lines nj ₃ .

[0087]

[Equation 36]

The smallest positive integer that satisfies (Equation 34) is nj ₁
If nj ₃ is the smallest positive integer that satisfies (Equation 36), then mf <nf, and therefore nj ₃ ≦ nj ₁ , and fast-forward reproduction is possible with a smaller number of jumping lines. Similarly, for the fast forward in the reverse direction, in the case of the first embodiment, (Equation 21) is substituted into (Equation 22) to obtain the following relational expression.

[0089]

[Equation 37]

From these (Equation 37) and (Equation 21), the following relational expression is obtained from the number of jumping lines nj ₂ .

[0091]

[Equation 38]

On the other hand, in the case of fast forward in the second embodiment, (Equation 29) is substituted into (Equation 30) to obtain the following relational expression.

[0093]

[Formula 39]

From these (Equation 39) and (Equation 29), the following relational expression is obtained by the number of jumping lines nj ₄ .

[0095]

[Formula 40]

Let nj _{2 be the} smallest positive integer that satisfies (Equation 38).
If nj ₄ is the minimum positive integer that satisfies (Equation 40), then mf <nf, and thus nj ₄ ≦ nj ₂ , and fast-forward reproduction is possible with a smaller number of jumping lines. As described above, according to the second embodiment, the controller performs the first operation of outputting the data of one unit screen from the reproduction start address so as to reproduce the data of one unit screen, as compared with the first embodiment. There is also an effect that fast-forward playback can be performed with a smaller number of jumping lines.

In this embodiment, the controller calculates the track jumping number and the increment amount of the reproduction start address after the track jump according to the fast-forwarding factor. However, the fast-forwarding factor, the track jumping number, and the jumping amount are set in advance. It is also possible to record a correspondence table with the increment amount of the subsequent reproduction start address in the ROM or the like and refer to the correspondence table.

In the present embodiment, one unit screen is reproduced, but a plurality of unit screens may be reproduced.

[0099]

As described above, according to the present invention, the number of rotations and the direction of rotation of the disk remain constant without changing,
This has the effect of realizing an excellent fast-forward playback device capable of fast-forward playback. Further, since it is not necessary to change the rotation of the disk, there is an advantage that the control structure for increasing the size of the drive motor or increasing the speed is unnecessary, and the tracking servo does not become unstable due to the increase in acceleration. It is a thing.

[Brief description of drawings]

FIG. 1 is a block diagram of a fast-forward reproduction device according to an embodiment of the present invention.

FIG. 2 is a sequence diagram for explaining a forward fast-forward reproduction operation in the first embodiment of the present invention.

FIG. 3 is a flowchart showing a forward fast-forward reproduction operation procedure in the first embodiment of the present invention.

FIG. 4 is a sequence diagram for explaining a reverse fast-forward reproduction operation in the first embodiment of the present invention.

FIG. 5 is a flow chart showing a reverse fast-forward reproduction operation procedure in the first embodiment of the present invention.

FIG. 6 is a sequence diagram for specifically explaining a fast-forward reproduction operation in the forward direction according to the first embodiment of the present invention.

FIG. 7 is a sequence diagram for specifically explaining a fast-forward reproduction operation in the reverse direction according to the first embodiment of the present invention.

FIG. 8 is a sequence diagram for specifically explaining a forward fast-forward reproduction operation according to the second embodiment of the present invention.

FIG. 9 is a sequence diagram for concretely explaining the reverse fast-forward reproduction operation in the second embodiment of the present invention.

FIG. 10 is a diagram showing an example of an optical disc for recording an image of NTSC system as a reference.

FIG. 11 is a block diagram showing a conventional example.

[Explanation of symbols]

 1 Track 2 Disk 9 Reading Means 14 Tracking Means 15 Controller 16 Jumping Means 18 Data Reproducing Means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mamoru Tokai, 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (3)

[Claims] 1. A sector composed of an address part and a data part has a track forming a continuous spiral, and image data of a plurality of screens is recorded by arranging in order of address in units of a predetermined number of sectors required for one screen. Disc, reading means for reading address information and data information, tracking means for tracking the reading means on a track, jumping means for jumping the reading means between tracks, and data output by the reading means. The data reproduction means for reproducing information and a controller are provided, and the controller calculates the number of track jumpings adapted to the fast-forwarding magnification and the increment amount of the reproduction start address after the track jumping, and the controller calculates one from the reproduction start address. Screen A first operation of outputting a signal to the data reproducing means so as to reproduce the data of a plurality of screens; and a second operation of outputting a signal to the jumping means so as to jump the reading means by the calculated number of track jumpings, A third operation for incrementing the reproduction start address by the increment amount is performed for each of the first, second and third operations.
A fast-forward playback device characterized by being repeated in the order of operation. 2. The number of sectors s constituting one round of a track in the case of forward fast forward, and the controller,
Positive integers nj ₁ and m ₁ satisfying (Equation ₁ ) and (Equation 2) are calculated from the number of sectors nf for recording data of one screen and the fast-forward magnification x, and the number of track jumping nj ₁ and that after jumping are calculated. The increment amount m ₁ * nf of the reproduction start address is calculated, and in the case of backward fast forward, the positive integers nj ₂ and m ₂ that satisfy (Equation 3) and (Equation 4) are calculated to determine the number of track jumping lines. _2. The fast-forward playback device according to claim 1, wherein nj ₂ and an increment amount m ₂ * nf of the playback start address after jumping are calculated. [Equation 1] [Equation 2] [Equation 3] [Equation 4] 3. When one screen consists of a plurality of unit screens,
In the case of fast forward in the forward direction, the controller counts the number of sectors S that make up one round of the track, the number of sectors nf that records data of one screen, the number of sectors mf that makes up the data of one unit screen, and the fast-forward magnification x. From the above, positive integers nj ₃ and m ₃ that satisfy (Equation 5) and (Equation 6) are calculated to calculate the number of track jumping nj ₃ and the increment amount m ₃ * nf of the reproduction start address after jumping, and In the case of reverse fast forward, positive integers nj ₄ and m ₄ satisfying (Equation 7) and (Equation 8) are calculated, and the track jumping number nj ₄ and the reproduction start address increment amount after jumping m ₄ * nf The fast-forward reproduction device according to item 1, wherein: [Equation 5] [Equation 6] [Equation 7] [Equation 8]