JPH01294201A - Disk medium for analog video signal recording - Google Patents

Abstract

PURPOSE:To record and reproduce a video signal and a non-video signal in independent areas respectively while holding a high reliability by discriminating the boundary between both recording areas of the video signal and the non-video signal and specifying signal forms of the video signal and the non-video signal. CONSTITUTION:A digital signal recording area 52 consisting of concentric circle- shaped tracks where the non-video signal is recorded with a digital signal is provided on the inner peripheral side of an analog video signal recording area 50, and at least one track on the boundary between recording areas is used as a boundary discrimination track 51 for discrimination of the area boundary. Therefore, the recording area 50 of the analog video signal which requires a high medium moving speed satisfies this requirement because being on the outer peripheral side of the disk, and the non-video signal is recorded with the digital signal which has a small information volume or to which a compensation technique can be freely applied regardless of a considerable information volume is recorded on the inner peripheral side of the disk 39 where the medium moving speed is higher. Thus, the video signal as well as the non-video signal is recorded and reproduced with a high reliability.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to electronic still camera systems, etc.
A magnetic disk medium for recording analog video signals that records multiple screens of analog still image signals on a track-by-track basis, that is, it has an analog video signal recording area consisting of a plurality of concentric tracks, and is driven to rotate at a constant angular velocity during recording or reproduction. This invention relates to digital media for recording analog video signals.

[Prior Art] An electronic still camera system has been developed that uses a floppy disk instead of a silver halide film. This electronic still camera system has various special features and functions ((+'i
However, one method is being considered in which not only the video signal but also digital data such as the date can be superimposed on the video signal and recorded on the rlR floppy disk, which would improve the functionality of the electronic still camera system. This makes it possible to use it in a variety of ways.

[Problems to be Solved by the Invention] However, the data superimposed on the video signal in this way cannot be rewritten independently if it is desired to be rewritten later, which is inconvenient. Therefore, if a track dedicated to digital signals is formed on the same disk separately from a recording track for analog video signals, the usage of the disk will be further expanded, and the functions of the electronic still camera system will be further diversified.

Generally speaking, if you try to widen the video signal band, the amount of information increases, and therefore the recording frequency band widens, and if you try to record in the form of an analog signal, the medium movement speed (track direction between the recording medium and recording head) increases. It is necessary that the relative movement speed of

Therefore, when the disk is driven at a constant angular velocity, in order to record and reproduce high-quality image signals, it is necessary to use the outer circumferential side of the disk as the video signal recording area. Furthermore, in an electronic still camera system, it is necessary to place emphasis on recording and reproducing video signals, so signals other than video are recorded in an area inside the video signal area.

The present invention provides a disc-shaped video signal recording medium that is provided with an analog video signal recording area consisting of a plurality of concentric tracks and that is rotated at a constant angular velocity during recording or playback. It is an object of the present invention to provide a disc medium that enables recording and reproduction of video signals and non-video signals in separate areas.

[Means for Solving the Problems] For the above-mentioned purpose, the present invention defines areas for recording video signals and non-video signals, makes it possible to identify the boundaries between the two areas, and furthermore, allows recording of video signals and non-video signals. The above purpose is achieved by specifying the signal form, and includes an analog video signal recording area consisting of a plurality of concentric tracks,
A digital signal consisting of concentric tracks for recording a non-video signal as a digital signal on the inner circumferential side of the analog video signal recording area in a disc-shaped video signal recording medium that is rotationally driven at a constant angular velocity in a recording or reproducing state. A recording area is provided, and at least one track at the boundary between the analog video signal recording area and the digital signal recording area is used as a boundary identification track for identifying the boundary between the areas.

[Function] According to the above configuration, areas on the recording medium for video signals and non-video signals are defined, and the analog video signal is placed on the outer circumference side where the medium movement speed is high, and the non-video signal is placed on the inner circumference side. Placement surface
Moreover, a track was provided at the boundary to identify the boundary.

For this reason, the recording area for analog video signals that requires a high medium movement speed is the outer periphery of the disk, which satisfies that condition, whereas the inner periphery of the disk, where the medium movement speed is low, has a small amount of information or a large amount of information. Even if the amount of information is large, it is possible to record and reproduce both video and non-video signals with high reliability.

[Example] FIGS. 6 to 8 are diagrams for explaining an electronic still camera system in which the disk medium for recording analog video signals according to the present invention is used, and FIGS. FIG. 6 is a view viewed from the upper right front, and FIG. 7 is a view viewed from the lower left rear. This atmospheric disc camera has the same shape and deafness as conventional cameras using silver halide photographic film, and is designed so that it can be operated in almost the same way.

In addition, in the same figure, the part names of each code are as follows.

1; Camera body, 2. strobe hot shoe,
3. Self-shutter LED, 4. Self-shutter, 5:
Shutter release button, 6; Shutter lock, 7:
Projection lens, 8; Shutter speed setting knob for auto/manual switching, 9; Head shift/forward button, 10: Head shift/reverse button, 11;
Erase button, 12: Door switch, 13; Door switch lock, 14: Eyepiece hood, 15: Ready LED, 1
6; Disk insertion slot door, 17; Battery box and power switch.

First, an overview of the magnetic disk camera will be explained.

A real image generated by the projection lens 7 is converted into a video signal by an image sensor made of semiconductor, which is appropriately processed and recorded on a magnetic disk. When taking pictures, this camera requires functions such as rotating the disk at high speed and stability and moving the magnetic head over the track to be recorded. A micro combinator is built into the camera to manage the sequence based on a predetermined program. Since the sequence is managed in this manner, malfunctions of the camera due to operational errors are prevented, and the user can safely concentrate on taking photographs.

When the user inserts the battery into the battery box, closes the lid 17 of the battery box, and sets it to the ON position, the control system is powered on and becomes ready for operation. Then, by pressing the door switch 12, loading the disc, capturing the subject in the finder, and pressing the shutter release button 5, the user can take a picture.

FIG. 8 shows an example of the display that appears in the finder. At the bottom of the screen, a list of used tracks of the discs currently loaded in the body and the head position are displayed. That is, track number (image recording track) 1
The display 18 located below 50 is a display that displays the used track number, and the display 19 located above is a display that displays the head position. C indicates a control track, and W indicates a cleaning track. Other displays are the same as those of conventional cameras, 20: matte surface, 21: split image, 22 nispeet light ready display, 23: aperture value display, 24: auto/manual shutter speed display. instrument, 25; auto/manual shutter speed pointer, 26; shutter speed 1 point pointer.

Next, an outline of the configuration and operation of the magnetic disk camera will be explained based on FIGS. 1 to 5, focusing on the relationship with the present invention.

FIG. 4 is a block circuit diagram of the camera, and FIGS.
Shutter release button 5, ffaψ shown in FIG.
3 lenses, forward shift/forward switch (button) 9, head shift/reverse switch (button)
10, Door switch 12, Semi-) 111 completion LED 15
, and the finder display sections 18 to 26, it is composed of the following components.

1!11, half mirror 26, sensor 27, sensor 1
- Driver 28, recording signal processing circuit 29, selector switch 3
0, recording amplifier 31, reproduction amplifier 31a, erasing amplifier 3
1b, changeover switch 32, head 33, finder eyepiece 31, half mirror 32, encoder 34, decoder 35, RAM 36, ROM 37, and CPU 38
It consists of

FIG. 5 is an explanatory diagram of the mechanisms around the disk of the camera, including the disk 39, disk case 40, disk clamp mechanism 41, head drive mechanism 42, disk case/shutter 43, disk presence/absence detection and disk release mechanism 44, Disc case shutter switch 45, disc rotation motor 46, pulse generator 47, door 48
and a door opener 49.

FIG. 1 is an explanatory diagram of the arrangement of the 1-rack on the disc of the present invention, in order from the outer circumferential side: the image recording area 50, the margin (
A guard band) 51, a used track number recording track 52, and a cleaning L-rack 53 are arranged concentrically.

FIG. 2 is an explanatory diagram of the format 1 of the used track number marking track 52 in the disc of the present invention, in which the track head mark H, data (track number)
, a boundary mark B, and a track end mark T.

In FIG. 4, the light flux incident from the photographing lens 7 passes through a half mirror 26 and forms an image on a sensor 27. A signal from the shutter release button 5 activates the sensor driver 28 to obtain a video signal, and the recording processing circuit 2
9. The head 33 is excited via the changeover switch 30, the recording amplifier 31, and the changeover switch 32. At this time, the head drive mechanism 42 moves the head 33 so that it contacts a suitable track in the image recording area 50 (FIG. 6) of the disk.
has been moved by. Further, the disk 39 is connected to the motor by a disk clamp mechanism 41, and the disk 39 is connected to the motor by a disk clamp mechanism 41.
It rotates stably at high speed (rpm) or 1800 (rpm). When the photographing is finished, the rotation of the disk 39 stops. The disk 39 is inserted or removed by pressing the door switch 12 and opening/closing the door 48.

Next, the operation of loading and unloading the disc in the camera will be explained according to the flowchart of the sequence of loading and unloading the disc shown in FIGS. 3(8) to 3(C).

When the door switch 12 is pressed and the disk 39 is not loaded yet, the path branches to a path without a disk and the door 48 is opened. Here, the disk 39 is loaded by the user. When the door 48 is closed, the disk 39 is clamped by a disk clamp mechanism 41, the disk case shutter 43 is opened by its opener 45, and the disk 39 is rotated. And disk 3
After cleaning the head 33 using the cleaning track 53 (see FIG. 1) formed on the head 3
3 to the used track number recorder 52 and trace it. The signal induced in the head 33 is supplied to the reproduction amplifier 31a via the changeover switch 32, and is amplified there. Its output is decoder 3
5, the used track number is reproduced and stored in the built-in memory (semiconductor RAM) 36. Based on this content, the head 33 is moved to the lowest numbered unused track, and the display section is activated to light up the used track number indicator 18 and the head position indicator 19 in the finder. As a result, the used track number and head position are displayed, and furthermore, the ready EDI 5 on the left side of the body 1 is lit. At this point, it was possible to take pictures.

Here, if the shirt release button 5 is pressed, the process branches to the photographing routine, and if t, 1, the rotation of the disc 39 is stopped and the disc loading sequence is completed.

Option 19 is possible at any time thereafter. If there is a change in the recorded track number of the disk due to photography or deletion, the contents of the built-in memory 36 are updated accordingly. By doing this, the correct recorded track number is always recorded in the built-in memory 36.

Next, the case where the disk is removed will be explained.

When the door switch 12 is turned on, the presence or absence of the disk 39 is checked by the disk presence/absence detection and disk release mechanism 44 (see the upper part of FIG. 3 (8)). Here, if the disk 39 is loaded, Branch to path (2) with a disk, turn off the READYLED 15, and display the recorded track number stored in the built-in memory RAM 36 on the used track number recording track 52 (
(See Figure 1). An example of the format is shown in FIG. In this recording format, one recording section is an arc looking at a central angle of 6 degrees. This is 6 for one rotation of the disk 39.
It is formed based on the output of pulse generator 47 which generates 0 pulses.

The data recorded is a used track number expressed in a 6-hit serial binary format. When writing this,
A track head mark H is recorded before the first data, a boundary mark B is recorded between the data D, and a track end mark T is recorded after the last data D. This recording signal is generated by the CPU 38 using the ROM 37 and encoder 34, and sent via the switch 30 to the recording path already mentioned (recording amplifier -> switch 32 - head 33). After recording the used track number on the disk 39 in this way, the head 10 is retracted, the data case shutter 43 is closed using the data case shutter opener 45, the door 48 is opened using the door opener 49, and the disk is opened. Put it in release state. Here, disk 3
9 and closing the door completes the disc ejection sequence.

In the block diagram shown in FIG. 4, only one head is provided, but a separate head exclusively for erasing may be provided. In this case, the image will be erased exclusively by the reproduction device. As a result, the design and arrangement of the head can be optimized so that only the used track number and rack can be efficiently erased.

Furthermore, data such as the azimuth type, photographing date, exposure conditions, etc. of the recording signal of each track may be recorded in the used track number recording tracks of FIGS. 1 and 2.

Although a magnetic camera using a 6n disk as a magnetic recording medium has been described above, it goes without saying that the present invention can be similarly applied to a magnetic camera using a magnetic drum.

[Effects of the Invention] As described above, in the present invention, areas are defined for recording video signals and non-video signals, the boundaries between the two areas are made distinguishable, and the signal forms of the video signals and non-video signals are specified.

That is, in a disc-shaped video signal recording medium that has an analog video signal recording area consisting of a plurality of concentric tracks and is rotated at a constant angular velocity during recording or reproduction, there is a A digital signal recording area consisting of concentric tracks for recording video signals as digital signals is provided, and at least one of the boundaries between the analog video signal recording area and the digital signal recording area is provided.
Since the track is a boundary identification track to identify the boundary of the area, since the recording area of the analog video signal that requires high medium movement speed is on the outer circumferential side of the disk, this condition is satisfied and playback is possible. The disc is configured so that a sufficient recording wavelength can be obtained, and even if there is a small amount of information on the inner circumferential side of the disk where the medium movement speed is low, or even a considerable amount of information, it can be recorded with a digital signal that can be used to make full use of compensation technology. Therefore, it is possible to provide an analog video signal recording disk medium that is capable of recording and reproducing both video signals and non-video signals with high reliability.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram of the layout of tracks on the disc, Knee, I
Figure S2 (of the used track number recording track) (7) Explanatory diagram, %3 Figure (A),
([1), (C) Before: A flowchart of the sequence of loading and unloading the magnetic disk in the 1Jiil 8-disk camera, Fig. 4 is a block circuit diagram of the magnetic disk camera, and Fig. 5 shows the disk peripheral part of the magnetic disk camera. Fig. 6 is an explanatory diagram of the mechanism of F
External view of the 11-ki disc camera seen from the upper right front, No. 7
This figure is an external view of the magnetic disk camera seen from the lower left rear, and FIG. 8 is a view of the display inside the finder of the magnetic disk camera. [Explanation of symbols of main parts] 39...Disc 50...Image recording area 51...Margin (gart band) 52...Used track number recording track 53...
Cleaning Truck Agent Patent Attorney Tadashi Sato Year 1 Figure 2 Ro Sai 5 CB) O 8 Figure

Claims (1)

[Scope of Claims] 1. In a disc-shaped video signal recording medium that includes an analog video signal recording area consisting of a plurality of concentric tracks and is rotated at a constant angular velocity during recording or reproduction, the analog video signal recording A digital signal recording area consisting of concentric tracks for recording non-video signals as digital signals is provided on the inner circumferential side of the area, and at least one track at the boundary between the analog video signal recording area and the digital signal recording area is used as the boundary of the area. A disc medium for recording an analog video signal, characterized in that it has a boundary identification track for identifying that it is an analog video signal. 2. The analog video signal recording area is the 1st track to the 50th track, the 51st track is a boundary track, and the 52nd track is a digital signal recording area. A disk medium for recording analog video signals.