JPH01120975A - Reproducing device - Google Patents

Abstract

PURPOSE:To prevent noise on the pattern by constituting a memory read means such that plural picture signals stored in a memory are read while the read range is changed relatively and supplied to a display means. CONSTITUTION:In applying normal reproduction, a reproduction operation switch (not shown) arranged in an operation section 15 is operated to read a reproducing signal by a magnetic head 3 from a track on a magnetic disk D driven at a prescribed speed by a motor 1 and supplied to a reproducing signal processing circuit 7. The reproducing signal subject to prescribed processing by the reproducing signal processing circuit 7 is converted into a digital signal by an A/D converter 8 and stored to any of field memories 9, 10. Succeedingly, the content of one field memory is read by a data selector 11 and converted into an analog signal by a D/A converter 12 and supplied to a monitor 13 and displayed as picture information.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a reproducing device that reproduces image information recorded on a recording medium and displays the reproduced image information on a monitor.

[Conventional technology]

2. Description of the Related Art Still video systems that record or reproduce still images on a recording medium called a video floppy are conventionally known.

In such a still video system, a plurality of concentric recording tracks are formed on a video floppy, and one field of image information can be recorded on each track. A non-recorded portion called a guard band is formed between each track to prevent crosstalk with adjacent tracks. For example, the standards for electronic still video systems include a track pitch of 100μ, a track width of 60μ, and a guard band of 40μ.

On the other hand, when reproducing image information from a recording medium on which multiple pieces of image information are recorded, each track on the recording medium is fast-forwarded in order to recognize each recorded information in a short time or to search for specific image information. The need often arises.

In this case, the head is moved continuously or intermittently in the direction in which the tracks are lined up on the rotating recording medium, and images of each track can be sequentially displayed on the monitor screen.

[Problem that the invention seeks to solve]

However, as mentioned above, when moving the head between multiple tracks on a recording medium, the head moves between the track where the signal is recorded, the guard band where the signal is not recorded, and the track where the signal is recorded. Because of this continuous movement, the reproduced image disappears in the guard band section and only noise is reproduced, and when switching between screens, a reproduced image with extremely degraded quality is displayed.

[Means for solving problems]

The present invention has been made to solve the above-mentioned problems, and includes a memory for storing a plurality of image information reproduced from a recording medium, and a memory reading means for reading out the information stored in the memory. , a display device for displaying image information read out from the memory by the memory reading device, wherein the memory reading device has a reading range of a plurality of image signals stored in the memory. By configuring the information to be read out and supplied to the display means while relatively displacing the information, it is possible to perform a so-called scrolling operation in which the recorded information in each track on the recording medium is gradually switched on the monitor screen. This prevents low-quality, noisy screens from being displayed during fast-forwarding or searching.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the reproducing apparatus according to the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a block diagram of a reproducing apparatus according to the present invention.

In the figure, D is a magnetic disk as a recording medium, ■ is a motor for rotating the disk, 2 is a motor servo circuit that rotates the motor l at a constant speed, 3 is a magnetic head that reproduces recorded information from the top of the magnetic disk, 4 is a head moving pulse motor that moves the magnetic head 3 in the direction in which the recording tracks on the disk D are lined up; 5 is a motor that drives the pulse motor 4 to move the magnetic head 3 to a predetermined track on the disk D. A drive circuit 6 is a preamplifier 1.7 that amplifies the information reproduced by the magnetic head 3 to a predetermined level.
8 is a reproduction signal processing circuit consisting of a demodulator for demodulating the recorded information recorded on the magnetic disk surface after being FM modulated, a de-emphasis circuit, etc.; 8 is a reproduction signal processing circuit which converts the reproduction video signal outputted from the reproduction signal processing circuit 7 into a digital signal; A/D to convert
converter, 9 is the first field memory, 10 is the second
11 is a data selector that selects from which field memory data converted into a digital signal is to be read out; 12 is a data selector IL that converts the digital signal data read out from the field memory 9 or IO into an analog video image; A D/A converter 13 converts the signal into a signal, and a monitor 13 serves as a display means for displaying the reproduced image signal. Reference numeral 14 denotes a control circuit that controls the operation of each of the above-mentioned circuit blocks, and is constituted by a CPU. Reference numeral 15 denotes an operation unit for instructing each operation mode, and in particular, 16 is a fast-forward playback switch for fast-forwarding the reproduced image.

Next, the operation will be explained.

First, when performing a normal playback operation, by operating a playback operation switch (not shown) provided in the operation unit 15, the magnetic head 3 plays back tracks from the magnetic disk opening which is rotated at a predetermined speed by the motor 1. The signal is read out and supplied to the reproduction signal processing circuit 7. The reproduced signal subjected to predetermined processing by the reproduced signal processing circuit 7 is converted into a digital signal by the A/D converter 8 and stored in either field memory 9 or 10.

Subsequently, the data selector 11 reads out the contents of one field memory, the D/A converter 12 converts the signal into an analog signal, and the signal is supplied to the motor 13 to be displayed as image information.

Next, a case will be described in which the recording information tracks recorded on the magnetic disk are successively fast-forwarded and reproduced one after another.

By operating the fast-forward playback switch 16 disposed in the operating section 15, a signal FF that remains at a high level throughout the operation is input to the control circuit 14 at the fast-forward input terminal IN, as shown in FIG. 2(a). be done.

The control circuit 14 generates a head feed pulse HMP (FIG. 2(b)) for driving the head drive →pulse motor 4 after a predetermined period of time from the rise of the signal FF in FIG. 2(a). The signal is then supplied to the motor drive circuit 5. In this embodiment, the pulse motor 4 moves the magnetic head 3 by one track by sending five pulses. Then, the magnetic head sequentially moves to the next track while tracing the guard bands between the tracks.

While the magnetic head 3 is moving, each time the magnetic head 3 is positioned on each track on the magnetic disk, an envelope E of the reproduced RF signal as shown in FIG. 2(C) is transmitted from the magnetic head 3.
NV is output and input to the reproduced signal processing circuit 7.

The reproduced signal processing circuit 7 demodulates the input FM-modulated recording information signal and performs processing such as de-emphasis, and then supplies the reproduced video signal to the subsequent A/D converter 8. The video signal is then encoded and converted into a digital signal by the A/D converter 8, and then transferred to the first and second field memories 9. IO.

On the other hand, the reproduced envelope signal ENV shown in FIG. 2(C)
is stabilized, that is, the drive pulse H of the pulse motor 4
After a predetermined period of time has elapsed since the final pulse of MP' (FIG. 2(b)), the control circuit 14 sends a control signal WE, (FIG. 2(b)) that permits writing to the first field memory 9.
d)), and the first field memory 9 stores the digital image information output from the A/D converter 8.

At this time, the control signal WE2 (FIG. 2(e)) that controls writing to the second field memory 10 is not enabled, and writing to the second field memory 10 is prohibited. do not have. Write control signal WE
,.

W] "]- shall permit writing when each is at Low level.

After the writing to the field memory 9 is completed, in order to move the magnetic head 3 again, the control circuit 14 drives the head feeding pulse motor 4 with a drive pulse HMv (FIG. 2(b)).
is generated, and the magnetic head 3 is moved. Then, in the same manner as described above, the reproduction signal processing circuit 7 reproduces a video signal from the reproduction RF signal ENV read by the magnetic head 3,
Output. This reproduced signal is digitally encoded by the A/D converter 8 and then supplied to the first and second field memories 9 and IO.

On the other hand, the write control signal WT to the first field memory 9 is at a high level, and writing to the first field memory 9 is prohibited, and nothing is written to the first field memory 9. The contents written last time are stored as they are. Also, at this time, the control signal WE2 goes low to enable writing into the second field memory 10, and thereby image information is written into the second field memory 10.

This operation is repeated while the fast-forward operation switch 16 is operated and its control signal FF (FIG. 2(a)) is at a high level.

Next, a case will be described in which image information stored in the field memory 9.10 is read out and displayed.

Field memory9. The read operation of lO is performed by the read control signals RE, (FIG. 2 (f)) and T (FIG. 2 (g)), which are respectively issued from the control circuit 14, and the read operation is performed when both are at low level. is permitted, and reading is prohibited when it is at Hi level.

Before and after writing to the first field memory 9 described above,
As shown in FIG. 2(f), the read control signal RE is at Hi level, and reading from the first field memory 9 is prohibited.

Further, as shown in FIG. 2(g), the read control signal RE of the second field memory IO is at a low level, and a read operation is permitted.

Next, when writing to the second field memory 10,
The read control signal r output from the control circuit 14 is at a low level as shown in FIG. 2(f), indicating that reading of information stored in the first field memory 9 is permitted. Furthermore, the read control signal RET is at Hi level as shown in FIG.

These field memories 9 and 10 can be read simultaneously, and their output data is input to input terminals A and B of the data selector 11.

This data selector 11 is controlled by a control signal DS (FIG. 2 (h)) supplied by a control circuit 14. When the control signal DS is at a low level, input terminal A is selected, and when it is at a high level, input terminal B is selected. configured to be selected. When the first field memory 9 writes, this control signal DS is transmitted to the input terminal B, that is, the second field memory 9.
The field memory 10 becomes H level so that it is selected, and after writing is completed, the inversion is repeated as shown in the figure. This inverted pulse is set so that the duty ratio gradually decreases in a period of 1v (one vertical scan), and when the second field memory IO starts writing, it becomes a low level for an IV period and the input terminal A, that is, the first The output of the field memory 9 is selected.

After the writing to the second field memory 10 is completed, the control signal DS generates a pulse as if the duty ratio gradually increases, and becomes Hi level for a period of 1v when the first field memory 9 starts writing. . Then, the output of the second field memory 2, that is, the input terminal B is connected to the data selector.

In this operation, the data for which the fast forward switch is selected is D/A.
The signal is restored to an analog signal by the converter 12 and supplied to the monitor 13 for display.

The switching operation of the data selector 11 described above will be explained in more detail with reference to FIGS. 3(a) to 3(f). Assuming that one screen of image information is stored in each IO, in the LV period indicated by a in FIG. 2(h), which field memory 9, 10
Since the control signal DS of the data selector 11 is at Hi level, the input terminal B is switched, and the image information stored in the field memory 10 is displayed on the display device, that is, the monitor 13. (
Figure 3(a)). In the next 1v period, the control signal DS is at a low level during the first tb period and at a high level during the subsequent tb' period. Therefore, during the first tb period, the data selector is connected to the input terminal
field memory9. tb/ period is input terminal B
That is, the contents of the second field memory 10 are displayed on the monitor screen, as shown in FIG. 3(b). Also next I
During the V period, the duty ratio of the pulse changes, with the first t6 period being at a low level and the subsequent tc' period being at a high level.
i level, and when compared with the previous lv period, tb<t
As shown in FIG. 3(c), the display area for the contents of the first field memory 9 is wider compared to the screen of The display area for the contents of the file IO becomes narrower.

In this way, the duty ratio of the pulse of the control signal DS is gradually adjusted to O<tb<tc within the lv period.
By gradually changing < t d < t e ≦ lv, the image shown in Figure 3 (a) is displayed on the monitor screen.
3 (b), (c),
(d).

As shown in (e), the image information in the first field memory 9 gradually descends from the top of the screen, the contents of the second field memory disappear to the bottom of the monitor screen, and the image information in the third field memory 9 gradually descends from the top of the screen.
In the state shown in Figure (f), the contents of the first field memory 9 are displayed on the entire monitor screen.

Subsequently, at position f in FIG. 2(h), reading of the second field memory 10 is inhibited by RET, and new image information is taken into the second field memory 10. Then, in the next 1v period g, contrary to the case of a-e, the first 1g period of the control signal DS is a high level pulse, the subsequent tg' period is a low level pulse, and furthermore, each successive IV period has a high level pulse at the beginning. The level period becomes longer (tg < th < tI < tk), and the second
The area occupied by the image in the field memory 10 on the monitor screen gradually becomes larger from the top of the screen, and the area occupied on the monitor screen by the image information in the field memory 9 corresponding to the brush 1 disappears toward the bottom of the screen. At this point, the image information in the second field memory 9 is completely displayed on the display screen, and reading of the first field memory 9 is prohibited by RE, and new image information is taken in by WE.

As described above, by alternately switching between the first field memory 9 and the second field memory 0, and at the time of switching, gradually displacing the reading range of the contents of each memory, the monitor A so-called scrolling operation can be performed on the screen to gradually switch from one screen to the next.

Further, by appropriately changing the order of reading from the memory, etc., it is possible to perform scrolling in both the up and down directions.

As described above, according to the present invention, the signals inside the memory are output and displayed on the monitor while the track is being advanced, and after the track is detected, the recorded information is written to the memory while being played back, and the memory is used to scroll from the previous screen. Since this is done, the screen can be fast-forwarded without displaying the noise playback screen when the screen changes.

The above-described operation is continued while the fast-forward switch 16 is pressed and the control signal FF shown in FIG. 2(a) is at Hi level.

In this embodiment, the pulse is applied in four stages until the image in the second field memory 10 at point a is completely switched to the image in the first field memory 9 at point e in FIG. 2(f). Although the duty ratio is switched, more precise scrolling can be performed by increasing the number of stages in which the duty ratio is changed. Furthermore, the scrolling speed can be freely set by increasing or decreasing the number of stages.

Further, in the above-described embodiments, the case where scrolling of recorded information on a recording medium is performed in fast forwarding, searching, etc. has been described, but scrolling reproduction may be performed in a normal reproduction mode.

Furthermore, by changing the order of read addresses from the memory, it is possible to scroll not only up and down but also in the left and right directions, which can be achieved by changing the memory address control.

〔Effect of the invention〕

As described above, according to the playback device of the present invention,
The recorded image information recorded on each track on the recording medium,
When playing continuously or intermittently, it is equipped with a memory that stores recorded image information, and while the track is being played, the signal in the memory is output to the monitor, and after a track is detected, it is written to the memory while playing, and the signal is transferred from the memory. When reproducing recorded image information, the reading range of multiple image signals can be read out while being relatively displaced and scrolled for display on the monitor screen. This prevents the reproduction of a noisy screen even between each track. In addition, high-quality image signals can be displayed continuously on the previous screen, main screen, and next screen without causing noise, image disturbance, etc.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of a reproducing apparatus according to the present invention, and FIGS. 2(a) to 2(h) are timing charts for explaining the operation of writing and reading image information signals to and from memory. , Figures 3(a) to (f') are especially the second
FIG. 7 is a diagram for explaining the display screen on the monitor screen in each operating state based on the operation explained in FIG. Explanation of symbols■・・・・・・・・・・・・・・・Motor 2...
...Motor servo circuit 3...
......Magnetic head 4...
...Head drive motor 5...
・・・Motor drive circuit 6・・・・・・・・・・・・・・・
・・Preamplifier 7・・・・・・・・・・・・・Reproduction signal processing circuit 8・・・・・・・・・・・・・A/D converter 9・・・・・・・・・・・・first field memory 10
......Second field memory 11 ・
・・・・・・・・・・・・Data selector 12...
......t...D/A converter 13...
...... Display device (monitor) 14 ......
......Control circuit 15...
.........Operation section 16...
...Fast forward switch tfn

Claims (1)

[Claims] A memory for storing a plurality of pieces of image information reproduced from a recording medium, a memory reading means for reading out the information stored in the memory, and a display for displaying the image information read from the memory by the memory reading means. A playback device comprising means, the memory reading means comprising:
A playback device characterized in that the playback device is configured to be able to read out a plurality of image signals stored in the memory while relatively displacing the readout range and supply the readout signals to the display means.