JPS6050663A - Recording and reproducing method of information signal - Google Patents

Abstract

PURPOSE:To reproduce an information signal independently of the speed of a recording medium by recording a signal block obtained by arranging the 1st signal having reference frequency and the 2nd signal having a frequency corresponding to the contents of the information signal symmetrically on both sides of a main signal. CONSTITUTION:The 1st signal section 12 having the reference frequency and the 2nd signal section having higher, lower or equal frequency than/to the reference frequency in accordance with the contents of the information are symmetrically arraged on both sides of the main signal section 11 and these signal blocks are successively recorded through blank sections 14. The reproduced signal is supplied to an envelop detecting circuit 23 and an inverter 24 through a reproducing amplifier 22 to detect the section 14 and supplied to an envelope detecting circuit 30 through an HPF29. A clock signal related to the carrying speed of the recording medium is supplied to a counter 24 and outputs sample and held 31, 32 by signals from decoders 27, 28 are compared by a comparator 33. Thus, the recorded information signal can be reproduced independently of the speed of the recording medium.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for recording and reproducing information signals on auxiliary tracks in, for example, a digital audio tape recorder.

´・l Technology and its problems For example, the track format in a fixed head digital audio tape recorder (DAT) is the first.
It is as shown in the figure.

In the figure, the chi 76 (1) is divided into two parts in the width direction, each serving as a recording surface in the forward direction and the reverse direction. On each recording surface, N data tracks (2) are provided, and furthermore, auxiliary tracks (3) are provided outside these data tracks (2).

The data track (2) records the PCM audio signal, sampling frequency, quantization bit number, emphasis, time code, etc. Small auxiliary truck (
3) various system control signals and additional information (for example, still images) are recorded.

There is a demand for performing what is called a high-speed search in such an AT. In that case auxiliary track (3)
It is necessary to be able to reproduce the necessary information even at high speed.

OBJECTS OF THE INVENTION In view of these points, the present invention makes it possible to reproduce information on auxiliary tracks regardless of the speed of the recording medium.

SUMMARY OF THE INVENTION The present invention provides a main signal section in which a first signal section having a reference frequency and a second signal section having a frequency higher or lower than the reference frequency or equal to the reference frequency depending on the content of the information signal are provided. The signal blocks provided symmetrically on both sides of the signal block are recorded in a quadratic manner through a predetermined blank section, and at the time of playback, the blank section in the playback signal is detected, and the playback signal is adjusted with respect to frequency. The signal is supplied to a filter having a characteristic having a predetermined slope, the output of the filter in the first and second signal sections is detected at a predetermined timing from the detection signal in the blank section, and the output of the filter is determined by comparing these detected values. , the content of the information signal can be determined by detecting whether the frequency of the second signal section is higher or lower than the reference frequency, regardless of the transport speed of the recording medium. This is a recording restriction method, and according to this method, all of the information on the auxiliary track can be reproduced regardless of the speed of the recording medium.

During recording of the embodiment, the signal recorded on the auxiliary track (3) is configured as shown in FIG. 2A. In the figure, a first signal section θ general (
A second signal section θJ having a frequency higher or lower than or equal to the reference frequency is symmetrically provided depending on the contents of the FF information. Then, these signal blocks are set to blank interval 0.
Via ◆, record the signal provided next on page j.

Next, FIG. 3 shows an example of a reproducing circuit for signals recorded in this manner. In the figure, (c) is the playback head from the auxiliary track (3), and the signal from the auxiliary track (3) is supplied to the envelope 144 via the playback amplifier (b) to the wave circuit. The output is supplied to impark (c) and a blank section α→ is detected as shown in FIG. 2B. This detection signal is supplied to the clear terminal of the counter (c). This counter (c) is also supplied with a clock signal related to the transport speed of the tape (1) from an arbitrary tape speed detection means (not shown). The count value of this counter (c) is supplied to decoders (a) and (c), and the timings shown in FIG. 2C and D are detected, respectively.

On the other hand, the signal from the amplifier (C) is passed through the bypass filter (C)
supplied to This bypass filter has a characteristic that the frequency of the recorded signal changes linearly as shown in FIG. 4 in the frequency range multiplied by the high-speed transport of the tape (1). The signal from this filter (c) then passes through the envelope detection circuit (a) to the sampling hold circuit 0m.

It is supplied to Pier 0. Signals at respective timings from the above-mentioned decoders (b) and (c) are supplied to the sampling and holding circuits 0me and 02, respectively, and sampling and holding is performed.

In other words, by being held at the timing shown in Figure 2C, a signal at a level corresponding to the frequency multiplied by the reference frequency is held, and the second signal is held at the timing shown in Figure 2. A signal having a level corresponding to the frequency multiplied by the signal in the interval (Ifl) is held. Here, these signals have the same multiplication rate, so the vertical relationship of the frequencies at the time of recording is detected as is.

Therefore, these Zanzo ring hold circuits 0]).

By comparing the output of Q → with the comparator circuit 0, the second
The cases in which the frequency of the signal section α1 is higher, lower, or equal to the reference frequency are detected, and the contents of the recorded information are outputted to the output terminals (b) Vcj1'y,p.

In this way (ff multiplier signal recording and reproduction is performed)7. However, according to this method, the speed of the recording medium J1. Reproduction can be performed without depending on LK.

The information recorded and reproduced in this manner is changed, for example, at predetermined time intervals, and this Lf is detected to constitute a linear counter. It is 11゛11I at the beginning of the grogram, lower at the end, and equal in between to mark the start and stop points of the grogram. This mark is repeated a predetermined number of times to become a chapter mark when a plurality of nologograms exist. Random access is performed by detecting the above mark. Perform the program Sugitsuno. Possible uses include cutting out unnecessary parts of commercials, etc.

It is also possible to insert various information data.

Furthermore, it can also be used as a speed control clock during editing, etc.

Effects of the Invention According to the present invention, information on the auxiliary track can be reproduced regardless of the speed of the recording medium.

[Brief explanation of drawings]

FIG. 1 is a diagram for explaining the background art, and FIGS. 2 to 4 are diagrams for explaining the present invention. 01) is the main signal section, α is the first signal section, cl is the second signal section, θ41d' blank section, 0) is the envelope detection circuit, (b) is the counter, (b) is the earphone decoder , (c) is Heino (Sufiruk, 0ρ, 0
N is a sampling and holding circuit, and (to) is a comparison circuit. 1st Rainbow 2 Drawing, [-1]-

Claims (1)

[Claims] A first signal section having a reference frequency and a second signal section having a frequency that is higher or lower than or equal to the reference frequency depending on the content of the information signal are provided symmetrically on both sides of the main signal section. The signal blocks are sequentially provided through a predetermined blank section, and all the signals are recorded, and at the time of playback, the blank section in the playback signal is detected, and the playback signal is passed through a filter having a characteristic having a predetermined slope with respect to the frequency. supply,
The output of the filter in the first and second signal sections is detected at a predetermined timing from the detection signal in the blank section, and by comparing these detected values, the output of the filter in the first and second signal sections is detected, regardless of the transport speed of the recording medium. A method for recording and reproducing an information signal, in which the content of the information signal is known by detecting that the frequency of the second signal section is higher, lower, or equal to the reference frequency.