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Description  |
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BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a magnetic recorder-reproducer in a video system
including a video camera, a video tape recorder and the like, and more
particularly to a magnetic recorder-reproducer capable of photographing
under an animation mode.
2. Description of the Prior Art
As one of several photographing methods using a video camera, there is a
so-called "animation" taking. This photographing method uses a technique,
wherein image signals are photographed in several fields, so that several
frames of images can be reproduced in one second for example, and, by
continuously reproducing this, a static object is reproduced as if driven.
The video camera used in this "animation" taking is capable of so-called
"joining taking." This "joining taking" is such that when the
photographing of the image signals in one field is completed, the next
field is photographed. A drivably controlled servo system is employed, so
that the photographed fields are continuous on a magnetic tape.
However, in the conventional video system, since the above-described
"animation" taking requires complicated operations for the photographing,
only some persons have performed the "animation" taking in actuality.
Thus, necessity has been voiced for a system for easily performing the
"animation" taking.
Furthermore, when automatic photographing is made during the photographing
under this animation taking mode, a few seconds lapse between a recording
operation and the succeeding recording operation. When a photographer puts
his hand in front of a lens of the video camera to move a subject to be
photographed during this period of time, there is a possibility of that
his hand thus put out is erroneously photographed with the subject because
the timing of the photo taking operation on the side of the video camera,
shifting from a resting state to a recording operation, is not known by
the photographer.
SUMMARY OF THE INVENTION
The present invention has been developed to obviate the above-described
disadvantages of the prior art and has as its object the provision of a
magnetic recorder-reproducer capable of easily photographing under the
animation taking mode.
To achieve the above-described object, the present invention features that,
in a magnetic recorder-reproducer capable of joining taking, upon
completion of recording, a tape is rewound, made to stand by for the
succeeding recording, and brought into a reproducing state at the time of
the succeeding recording, whereby the speed and phase of the reproducing
servo are locked and a reproducing system is switched over to a recording
system at about the time of completion of the preceding recording. A
mechanism is provided, in which the recording is ended, after a lapse of a
photographing time corresponding to one frame from the time of the
aforesaid succeeding recording, and thereafter, rewinding of the tape for
the aforesaid joining taking and stand-by for the succeeding taking are
performed.
Another object of the present invention is to provide a magnetic
recorder-reproducer, wherein unintentional photo taking can be avoided
under the animation taking mode.
To achieve the above-described object, the present invention features a
magnetic recorder-reproducer in which, upon completion of recording, the
tape is rewound, made to stand by for the succeeding recording, and
switched into the reproducing mode at the time of the succeeding
recording. The reproducing system is switched to the recording system at
about the time of the completion of the proceeding recording. The magnetic
recorder-reproducer including a mechanism which, after a lapse of
photographing time corresponding to one frame from the time of the
succeeding recording, ends said recording, and rewinds the tape for the
aforesaid joining taking, and puts the recorder-reproducer in standby mode
for the next use.
BRIEF DESCRIPTION OF THE DRAWINGS
The exact nature of this invention, as well as other objects and advantages
thereof, will be readily apparent from consideration of the following
specification relating to the accompanying drawings, in which like
reference characters designate the same or similar parts throughout the
figures thereof and wherein:
FIG. 1 is a block diagram showing the arrangement of the magnetic
recorder-reproducer according to the present invention;
FIG. 2 :s a block diagram showing the arrangement of the animation taking
control circuit of as shown in FIG. 1;
FIG. 3 is a timing chart showing the operation of the animation taking
control circuit; and
FIG. 4 is a sequence diagram showing the control sequence under the joining
taking mode.
DETAILED DESCRIPTION OF THE INVENTION
Detailed description will hereunder be given of the preferred embodiment of
a magnetic recorder-reproducer according to the present invention with
reference to the accompanying drawings.
Prior to the description of the embodiment, the control sequence under the
"joining taking" mode will be described with reference to FIG. 4.
Referring to FIG. 4, in the magnetic recorder-reproducer having a function
of the joining taking, upon completion of taking one photograph, a
magnetic tape is stopped by a capstan inverting brake and a record
processing circuit is automatically set at the state of recording pause.
At this time, the magnetic tape normally overruns a desirable stop
position , i.e. a record ending position f.sub.1 (an overrun value
.alpha.). Subsequently, the magnetic recorder-reproducer is automatically
set at rec pause reverse (RPR), whereby the magnetic tape is fed in
reverse and stops at about a stop position f.sub.2 being sufficiently more
on this side than the aforesaid stop position f.sub.1. An overrun value at
this time is set at .beta..sub.1 (1-A, 2-A).
Subsequently, the magnetic recorder-reproducer is automatically set at rec
pause forward (RPF), whereby the magnetic tape is fed in the forward
direction, stopped at f.sub.3 (close to the stop position f.sub.2),
released from the rec pause, and prepared for the succeeding
photographing. An overrun value at this time is .beta..sub.2 (2-B). The
purpose for performing this RPF is to avoid a sag of the magnetic tape due
to a function of the mechanism.
When the succeeding photographing operation is started, the RPF operation
is started again, a track recorded during the preceding photographing is
reproduced, the speed and phase of the reproducing servo system are locked
against the tape, and the recording meeting the preceding recording in the
speed and phase is made possible (3-A). From this point, the servo system
is switched from the reproducing system over to the recording system from
two fields more on this side than the stop position f.sub.1 in 1-A (3-B).
Subsequently, recording of the succeeding photographing is started from
the stop position f' in 1-A (3-C). Here, starting of recording of the
succeeding photographing need not necessarily coincide with the stop
position f.sub.1, and, for example, the final two fields of the preceding
recording may be rerecorded.
By the above-described control sequence, on the magnetic tape, it becomes
possible to perform the "joining taking" for connecting the portion
recorded by the preceding photographing. to the portion recorded by the
succeeding photographing
Next, FIG. 1 shows the arrangement of the magnetic recorder-reproducer
according to the present invention. Referring to FIG. 1 designated at 10
is a video camera head, wherein images, etc. are controlled by a control
section 20. The control section 20 further effects drivable control of
respective servo systems including an ATF(Auto Tracking Follow) servo 30,
a drum servo 40 and a capstan servo 50, control of the control circuit 60
of the animation taking, and drivable control of a mode control motor 22
for driving a tape reel 12.
Further, the control section 20 is inputted thereinto with output signals
showing the various conditions of the video camera system, input signals
from various sensors 34, an output signal from video function buttons 36
and the like, and controls various mechanisms of the video camera system
in accordance with the aforesaid signals inputted thereinto.
The ATF servo 30 is a tracking control mechanism when an image signal track
recorded on a magnetic tape is reproduced, wherein, for example, pilot
signals doubly recorded on respective image tracks are detected from an
image-sound circuit 28, and makes the drum servo 40 and the capstan servo
50 operate in such a manner that a magnetic head accurately follows the
track. The drum servo 40 is a mechanism for servo-controlling a drum motor
24 for rotatably driving a drum provided on the outer peripheral surface
thereof with an A head 16, a B head 18 and an erasing head 19, which, for
example, during recording, controls the speed and phase of recording of an
input image signal, and, during reproducing, controls the speed and phase
of reproducing of an output from the ATF servo system.
Here, the erasing head 19 is a flying erase head. When a fixed type erasing
head is used, so-called rainbow noises are produced due to the
interference of a recorded signal before being erased with a recorded
signal after being erased.
To perform the aforesaid "joining taking" in the video camera system as
described above, when a release button among the video function buttons 36
is operated to complete photographing of a first scene for example, the
control section 20 sets the video camera system at rec pause state,
operates the drum servo 40, the capstan servo 50 and the mode control
motor 22, whereby the operations RPR (2-A) and RPF (2-B) are performed,
thus completing a first recording. Thereafter, when a second photographing
is performed, the control section 20 operates the ATF servo 30, the drum
servo 40, the capstan servo 50, etc., whereby the operation of RPF (3-A,
3-B) as shown in FIG. 4 is operated, thus enabling the perforing of the
joining taking.
Designated at 42 is a connector, through which connection can be made with
an external mechanism, such as a television set.
As shown in FIG. 2, the animation taking control circuit 60 incorporates
therein various timers such as time setting circuits 70 and 72 for
performing control of taking times when photographing is made under the
animation taking mode, a time setting circuit 76 for performing the start
of one frame photographing in response to a taking command, a time setting
circuit 78 for performing control of animation taking interval times under
the automatic animation taking mode, and a time setting circuit 82 for
performing the driving of a buzzer 52 to begin the preparation for
photographing. Here, "one frame" in one frame photographing refers to a
static subject photographed and recorded by 4 fields, 8 fields and 12
fields as a unit, for example. In this example, it becomes possible to
reproduce 15 frames, 7.5 frames and 5 frames per sec. The control circuit
60 is connected to the control section 20 through connecting lines 202 and
204, and further, connected to an animation taking switch 54, as being a
main switch for the animation taking, a one frame taking switch 58 for
manually performing an actual photographing after the completion of
preparation for the animation taking, and a timer switch 56 for performing
the automatic animation taking.
In the magnetic recorder-reproducer with the above-described arrangement,
portions other than the animation taking control circuit 60 are not varied
in arrangement from the conventional example, and hence, action of the
animation taking control circuit 60 will be described hereunder with
reference to the timing chart shown in FIG. 3. Under the animation taking
mode, the animation taking switch 54 is closed. Power is supplied from a
power source at a time t.sub.1. Thereafter, the one frame taking switch 58
is closed for the manual animation taking. And, the timer switch 56 is
closed for the automatic animation taking. During the manual animation
taking, a recording start signal of a pulse width T.sub.4, which is set in
a T.sub.4 time setting circuit 78, is immediately outputted to the control
section 20. During the automatic animation taking, the recording start
signal of the pulse width T.sub.4, which is set in the T.sub.4 time
setting circuit 78, is outputted at a time t.sub.2 for example, and at
intervals of time T.sub.3 set in the T.sub.4 time setting circuit 78 to
the control section 20 through the diode 80, the resistor 86, the
transistor 88 and the terminal 104.
The control section 20 outputs a recording signal (REC) rising at a time
t.sub.3 after a lapse of a predetermined period of time upon receiving the
start signal to a terminal 100 of the animation taking control circuit 60.
In the animation taking control circuit 60, a stop signal of a pulse width
T.sub.2 is produced by the T.sub.1 time setting circuit 70 and the T.sub.2
time setting circuit 72 at the time t.sub.4 after a lapse of the time
T.sub.1 from the time t.sub.3, and this stop signal is outputted to the
control section 20 through a diode 74, the resistor 86, the transistor 88
and the terminal 104. In the control section 20, the recording signal is
made to rise at a time t.sub.5 after a lapse of a predetermined time upon
receiving the stop signal, whereby the recording operation is stopped.
Thereafter, a pause signal (PAUSE) indicating the state, when the
preparation for photographing is completed, is outputted from the control
section 20 to a terminal 102 of the animation taking control circuit 60 at
a time t.sub.6. In a T.sub.5 time setting circuit 82, a driving signal to
operate a buzzer 84 for a period of time from a rising time of the pause
signal to the time T.sub.5 is outputted to the buzzer 84. As a result, the
photographer photographing under the animation taking mode can learn that
preparation for the succeeding animation taking in completed through a
warning sound given by the buzzer 84.
A warning sound other than the warning sound, which is given at the time of
completion of the preparation of photographing may be given during
recording. With this arrangement, a time interval from the time of
completion of the recording operation to the time of completion of the
preparation of photographing can be reliably grasped.
As described above, according to this embodiment, during photographing
under the animation taking mode, the photographer can avoid mistakenly
putting his hand out in front of the lens of the video camera while
switching the subject to be taken during recording.
As has been described hereinabove, by use of the magnetic
recorder-reproducer according to the present invention, photographing
under the animation taking mode can be performed and the recording timing
of the video camera can be accurately grasped, so that mistaken taking
during photographing under the animation taking mode can be obviated.
It should be understood, however, that there is no intention to limit the
invention to the specific forms disclosed, but on the contrary, the
invention is to cover all modifications, alternate constructions and
equivalents falling within the spirit and scope of the invention as
expressed in the appended claims.
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