JPS608523B2 - Simultaneous image and audio playback device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides the ability to
This invention relates to a simultaneous image and audio reproduction device that reproduces an image signal and an audio signal at the same time, and furthermore, it changes the pitch in the reproduction output of an audio signal when the reproduction state of the image signal is different from the standard reproduction state. The present invention relates to a simultaneous image and audio reproduction device that obtains audible audio signals.

As shown in FIG. 2, the magnetic tape (recording medium) on which image signals and audio signals are recorded using the helical scanning cram school NTR is tilted with respect to the direction F' in which the magnetic tape 11 should be run, and the image signals are recorded. Image tracks 12 are formed in parallel with each other, and an audio track 13 on which an audio signal is recorded is formed in parallel with F, and a control signal with a constant frequency Y (for example, several hundred) is formed in parallel with F. A recorded control track 14 is formed thereon.

Therefore, in order to reproduce images and audio signals from such magnetic tape 11, as shown in FIG. 12 and transports the magnetic tape 12 in the direction of arrow S at the same speed V (standard speed) as when recording on the magnetic tape. That is, a reference signal of a frequency $ serving as a reference is generated in advance from the reference signal generator 18, and the magnetic tape 11
A control signal is reproduced from the upper control track 14 by a magnetic head 19, and after being shaped by a waveform shaping circuit 201, it is compared with the reference signal in a comparator 21 to derive a comparison output.

The comparison output derived from the comparator 21 in this manner is applied to a motor drive circuit 22, and the motor drive circuit 22 supplies a drive signal corresponding to the comparison output to a motor 23 connected to the capstan 17. Therefore, the motor 23 is controlled so that the frequency of the control signal reproduced from the magnetic tape 11 is always equal to the reference signal frequency, and the motor 23 is controlled at the standard speed V.
It is driven at a constant speed.

If the magnetic head 29 is placed opposite the audio track 13, the audio signal recorded on the magnetic tape 11 can be normally reproduced. On the other hand, the drum 15
A magnetic head 28 is disposed in a slit 25 fixed to the tip of an arm 27 rotated by a motor 26, and the motor 26 is controlled by a constant speed drive source 24 to form an image track 12 on the magnetic tape 11. By driving the magnetic head 28 at a speed equal to the above speed, the image signal recorded on the magnetic tape 11 by the magnetic head 28 can be normally reproduced.

As mentioned above, by running the magnetic tape 11 at the same speed (standard speed) as during recording, the same audio signal as during recording can be obtained, and the movement of the magnetic head 28 By setting the speed to be the same as the image track formation speed, it is possible to obtain the same image signal as during recording.

However, when reproducing the magnetic tape 11 as described above with the reproducing apparatus shown in FIG.
If the magnetic tape 11 is moved faster, a playback track as shown in FIG. By slowing down the transport, a playback track as shown in FIG. 2, 30-2 is formed, and a slow motion image signal is obtained.

As mentioned above, the magnetic tape 11 is extremely convenient because the state of the image signal can be easily changed simply by changing the transport speed of the magnetic tape 11.

However, when the state of the image signal is changed in this way, the running speed of the magnetic tape 11 changes, resulting in the inconvenience that the audio signal is not reproduced normally. The present invention eliminates the drawbacks of the conventional method by converting the pitch of an audio signal using a control signal reproduced from a magnetic tape. FIG. 3 shows the present invention in detail. Here, 31 is a first shift pulse generator for supplying shift pulses to a shift register 32, which will be described later. The pulse frequency 31 is selected to be K (K is a proportionality constant) so as to correlate with the frequency fc of the control signal obtained from the magnetic head 19.

33 indicates a constant frequency fo (this fo is expressed by &o = K, where &o is the frequency of the control signal obtained from the magnetic head when the magnetic tape 11 is run at the same speed (standard speed) as during recording). This is a second shift pulse generator that generates shift pulses (selected as follows), and applies the shift pulses to a shift register 34, which will be described later.

The shift registers 32 and 34 are each constructed by cascading n memory elements, and each derives an output from only one memory element, and the memory element that derives this output is the one that receives the shift pulse. It is constructed so that it is sequentially shifted in the direction of the arrow in response to the application, and after reaching the storage element Mn or mn, returns to the storage element MI or nl. The output of the magnetic head 29, in other words, the reproduced audio signal, is applied to the terminal 36, and this state is controlled by the switching transistor G1 controlled by the output signal of each storage element of the shift register 32. , G2, . . . Gn are connected to storage elements C1, C2, . . . Cn consisting of capacitors.
It is connected to the.

Therefore, by applying a shift pulse to the shift register 32 while applying the output of the magnetic head 29 to the terminal 36, the switching transistors G1, G27, . ……
, Gn are sequentially turned on, and as a result, the memory elements C1,
C2,.・・・．・・・． ... Analog quantities sampled sequentially will be stored in Cn. On the other hand, the output of each storage element of the shift register 34 is the switching transistor g.
1, g2, river ""... Since it is connected to the control electrode of Liu, this switching transistor is also turned on every time the output is derived from each storage element, and the terminal 38 is connected to the switching transistor g that is turned on. It is possible to read out the charges accumulated in the memory element.

Therefore, the storage element sequentially samples and stores the audio signals reproduced at a speed corresponding to the frequency of the control signal, and the audio signals sampled and stored at a constant frequency are sequentially derived from the storage element. .

If configured like this, when trying to obtain a frame-drop image,
If you want to increase the frequency of the reference signal fs, use "magnetic tape 1".
1 is transported at a speed faster than the standard speed and can obtain a desired frame-dropped image signal.

As described above, as the transport speed of the magnetic tape 11 increases, the frequency of the reproduced audio signal also increases, making it unlistenable. However, in the present invention, the frequency of the control signal detected by the magnetic head 19 also increases. Moreover, the audio signal reproduced at a frequency correlated with the frequency of this control signal is sampled and stored in a storage element, and the information is sequentially read out from the storage element at a predetermined constant frequency. Since the time axis has been compressed, the pitch of the audio signal reproduced by the magnetic head 29 can be changed to create an audio signal that can be listened to.

Conversely, if you lower the frequency of the reference signal $,
The magnetic tape 11' is transported at a speed slower than the standard speed V, and a slow motion image signal can be obtained. When the transport speed of the magnetic tape 11 is slowed down in this way, the frequency of the reproduced audio signal becomes low and becomes unlistenable, but the frequency of the control signal detected by the magnetic head 19 also becomes low, and the control signal The audio signal reproduced at a frequency correlated with the frequency of the signal is sampled and stored in a storage element, and information is sequentially read out from the storage element at a predetermined constant frequency, so the time axis of the audio is expanded. The pitch of the audio signal reproduced by the magnetic head 29 can be converted to make the audio signal suitable for listening. As described above, the present invention controls the pitch of the audio signal by the reproduction frequency of the control signal stored on the magnetic tape that stores the image signal and the audio signal, so the reproduction state of the image signal can be changed to any state. This is something that can be achieved.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing a conventional simultaneous image and audio reproduction device, FIG. 2 is an explanatory diagram of a magnetic tape applied to the reproduction device of FIG. 1, and FIG. 3 is a circuit diagram for explaining the present invention. Here, 11 is a magnetic tape, 12 is an image track, 13 is an audio track, 14 is a control track, 31 is a first shift pulse (first clock signal) generator, and 33 is a second shift pulse (second clock signal). ) generator, 33 and 34 are shift registers, and CI, C2, . . . , Cn are storage elements. Tsutomu - Illustrated 2 Illustrations 3 Illustrations

Claims (1)

[Claims] 1 A recording medium in which an audio signal and a constant frequency control signal are recorded on a longitudinal track and an image signal is recorded on a number of tracks formed in a direction intersecting the longitudinal direction is run, and the image signal and audio signal are simultaneously reproduced. In a playback device for normal playback, the playback control signal is used to control the running of the medium to play back the same image signal and audio signal as during recording, and the playback control signal is used to play back the same image and audio signals as during recording. When reproducing the image signal and the audio signal by controlling the running speed of the medium to a speed different from that during recording, the audio signal is sampled with a first clock signal obtained using the reproduction control signal. , store this in the memory element group,
A simultaneous image and audio reproducing apparatus characterized in that the stored contents of this memory element group are read out using a second clock signal of a constant frequency that is separately set based on the running speed of the medium at the time of recording.