JPH0413202A - Magnetic recording method - Google Patents

Abstract

PURPOSE:To increase the number of tracks essentially by recording another digital signal in depth layer on the recording area of a digital signal with a fixed head before recording the digital signal. CONSTITUTION:The area of a magnetic tape 1 is divided into an analog video signal recording area 2 by a helical scan system and a digital PCM audio signal recording area 3, and the depth layer recording of a digital still picture signal is performed on the PCM audio signal recording area 3 with the fixed head 10 along the longitudinal direction of the tape. Thereby, the digital signal recorded previously is not erased even when the digital signal is recorded on a depth layer-recorded area afterwards by the helical scan system, which increases the number of tracks essentially.

Description

Detailed Description of the Invention <Industrial Application> The present invention improves the method of recording analog signals and digital signals in separate areas of the same magnetic recording medium using a helical scan method, and increases the number of tracks. technology that enables a substantial increase in

<Prior art> As a technique for recording this type of analog signal and digital signal in separate areas using a helical scanning method, the l8e
! The ``8mm video standard'' standardized by the ``J Video Conference'' is well known. An overview of this standard is shown in Table 1, and the tape format and one-track link format are shown in Figure 4.

Table 1 In Fig. 4, 1 is an 8-radius metal magnetic tape, and the recording surface of the magnetic tape 1 has a video signal (analog signal) recording area 2 using the helical scan method and a PCM recording area using the helical scan method in the radial direction. It is divided into an audio signal (digital signal) recording area 3, and an audio track 4 and a cue track 5 using a linear recording method (fixed head) along both sides of the tape.

The magnetic tape 1 is wound 221 degrees around a rotary head having two heads, and tracks 7 are formed alternately along the helical scan direction 6 by each head. Approximately 5/6 of one track 7 is the video signal recording area 2A.
The remaining approximately 1/6 is the PCM audio signal recording area 3A. However, details such as guard hands will not be explained.

8mm video cameras are mainly used for recording moving images, and although they are highly regarded as being able to record moving images in high quality, they are not capable of recording still images in high quality.

When photographing a subject with an 8mm video camera, there is a demand for recording the resulting noise as a still image in high quality.In response to this, we converted the analog signal of the still image to a digital signal and converted it to a PCM audio signal. Instead, an attempt has been made to apply the signal to a rotary head and record along a large number of PCM audio recording areas 3A using a linear scan method.

However, with this digital still image recording method, once the digital signal of the still image is recorded, the still image cannot be erased.
), there is an inconvenience that PCM audio signals cannot be recorded, and there is also an inconvenience that an unbelievable signal is output when the PCM audio signal is intended to be played back with a device that conforms to the 8 mm video standard.

<Problems to be Solved by the Invention> In view of the above-mentioned prior art, the present invention provides a magnetic recording method that can substantially increase the number of tracks and record different signals while making use of the conventional recording format. The purpose is to

Means for Solving the Problems> A magnetic recording method according to the present invention records an analog signal and a digital signal in separate areas of the same magnetic recording medium by a helical scan method, and includes the following steps: The method is characterized in that, before the digital signal is recorded, another digital signal is deeply recorded in the recording area of the digital signal using a fixed head.

Effect> Even if a digital signal is later recorded in the deep recorded area using the helical scan method, the previously recorded digital signal will not be erased, and the number of tracks will substantially increase.

Example of implementation An embodiment of the present invention will be explained with reference to FIGS. 1 to 3.

Figures 1 and 2 show a recording format when the present invention is applied to 8 mm video, in which a magnetic tape 1 with an 8-line width has an analog video signal recording area 2 using a helical scan method, and a digital PCM audio signal. The recording area 3 is divided into a recording area 3, and digital still image signals are deeply recorded in the PCM audio signal recording area 3 by a fixed head (numeral 10 in FIG. 3) along the longitudinal direction of the tape.

In magnetic recording using the linear recording method using the fixed head 10, the recording wavelength is set longer than that using the helical scanning method, and therefore, as shown in FIG.
The signal is recorded until Furthermore, in the helical scan method, the recording wavelength is set to be shorter than that in the linear recording method, and a signal is recorded in the surface layer region 9. Note that lA indicates the base 1 of the magnetic tape l, and 11 indicates a rotating head. Furthermore, the fixed head 10 and the rotary head 11 have different azimuths.

Therefore, if a digital still image signal is first recorded in the PCM audio signal recording area 3 using the linear recording method using the fixed head 10, and then a digital PCM audio signal is recorded using the rotating head 11 using the helical scanning method. For example, the previous digital still image signal can be reproduced without being erased, and the subsequent PCM audio signal can also be recorded and reproduced as desired. In addition, as before, in the video signal recording area 2, the analog 4G video signal is recorded using a helical scan method.
1, but the context of the recording with the digital still image signal and the PCM audio signal is not required.

However, when operating an 8mm video camera, if there is a scene that you would like to record as a still image while shooting a movie, the circuit should be configured so that the still image signal can be recorded with the fixed head 10 by operating an appropriate switch. Good.

FIG. 3 shows an example of installing the fixed head 10, and the rotating head 1
The fixed head 10 is installed on the upstream side of the head 1 in the tape running direction. In the figure, 12 is a capstan, 13 and 14 are video tape cassette reels, and 15 is a guide pole.

In this embodiment, a plurality of n recording tracks 16 for digital still image signals are formed in the PCM audio signal recording area 3, and therefore the fixed head 10 is an n-channel multi-head.

In the above embodiment, an example was given in which the digital still image signal is first recorded in the deep layer, and the PCM audio signal is later recorded in the surface layer, but the combination of digital signals is arbitrary, and Table 2 shows examples of the combinations. Furthermore, the magnetic recording medium is not limited to the magnetic tape 1, and the signals recorded in the analog signal recording area 2 are not limited to video signals.

Table 2 Ru.

In the drawing, 1 is a magnetic tape, 2 is an analog video signal recording area, 3 is a digital PCM audio signal recording area, 8 is a deep recording area, 9 is a surface recording area, 10 is a fixed head, 1
1 is a rotating head, and 16 is a recording track for digital still image signals.

<Effects of the Invention> According to the present invention, by later recording another digital signal on the surface layer using a rotating head in an area where a digital signal has been recorded deep using a fixed head, the previously recorded digital signal is not erased. Since it can be played back, the number of tracks can be substantially increased.

[Brief explanation of drawings]

Claims (1)

[Claims] In a magnetic recording method in which an analog signal and a digital signal are recorded in separate areas of the same magnetic recording medium by a helical scan method, before recording the digital signal, in the recording area of the digital signal, A magnetic recording method characterized by deep recording of another digital signal using a fixed head.