KR0129961B1 - Recording format for an audio signal and a vcr circuit and method of operation for producing same - Google Patents

Abstract

The 1st thru 4th A/D converter(11-14) of the audio signal recording system converts the inputted analogue audio signal into the digital data and store in the 1st thru 4th memory(21-24). The stored audio data is converted to the appropriate signal form for the magnetic tape recording and is recorded on the magnetic tape. The record process part(40) modulates it to the signal suited for recording like EFM signal. The 4 head(51-54) which records the output of the record processing part(40) is enabled according to the head enable signal of the control signal generator(30) and is recorded in the audio sector designated on the track.

Description

Audio signal recording format and recording method of video cassette recorder and apparatus therefor

1A and 1B are diagrams for explaining a recording format of magnetic tape recorded according to an audio signal recording method of a conventional VCR.

2 is a block diagram according to an embodiment of an audio signal recording apparatus of a VCR according to the present invention.

3 is a view for explaining the angle of the magnetic tape is wound around the head and the drum on the drum for better understanding of the present invention.

4 is an operation timing diagram for the audio signal recording apparatus shown in FIG.

5 is a block diagram of another embodiment of an audio signal recording apparatus of a VCR according to the present invention.

6 is an operation timing diagram for the audio signal recording apparatus shown in FIG.

7A to 7C are diagrams for explaining the recording format of magnetic tape recorded according to the audio signal recording method according to the present invention.

* Explanation of symbols for main parts of the drawings

11 to 14 and 111 to 114: analog / digital converters

21 to 24 and 121 to 124 memory 30 and 130 control signal generator

40, 140: recording processing units 51 to 54, 151 to 154: head

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an audio signal recording format, a recording method, and an apparatus for a video cassette recorder. In particular, an audio signal of N channels is divided into N sectors on a track of a magnetic cape, and is distributed on a predetermined number of tracks. The present invention relates to an audio signal recording format, a recording method, and an apparatus for reducing the number of edit gaps.

A video cassette recorder for broadcasting systems (hereinafter referred to as VCR) that records commonly used entity Ssh (hereinafter referred to as NTSC) signals can record video and audio signals on tracks of magnetic tape. The recording capacity is not large, usually about 130 to 250 Mbps (Mega Bit Per Second). In particular, in order to record a signal requiring a large recording capacity at about 1.2 Gbps (Giga Bit Per Second), such as a high definition (HD) broadcasting signal, on a magnetic tape, it is necessary to efficiently use a limited magnetic tape recording area. Will be.

In order to record more signals on the track of the magnetic tape having such a limited length, there may be two methods. First, there is a method of increasing the recording density by making the wavelength of the signal for recording on the magnetic tape as short as possible. Second, securing a valid data recording area on the helical track of the magnetic tape.

The first method has significant difficulties and limitations in production such as reducing the video head gap. Therefore, it is more desirable to reduce the area occupied by the edit gap existing in the empty area between the sectors on the existing helical track as a method of securing the valid data area proposed in the second method.

This edit gap is a data storage area that exists at regular intervals between sectors in order to eliminate the interference between signals recorded in units of sectors and to provide independent editing areas. Such an edit gap exists between the audio sector and the audio sector or between the video sector and the audio sector.

FIG. 1A shows a tape format in which video and audio signals are recorded using four channels, and FIG. 1B shows a tape format in which video and audio signals are recorded using eight channels.

Here, each track consists of one video sector and four audio sectors for recording an audio signal as shown in FIG. 1A, and one video sector and eight audio sectors as shown in FIG. 1B. It is.

As shown in FIGS. 1A and 1B, there are four and eight edit gaps, that is, N edit gaps corresponding to the number of channels per track, respectively, on one track. In fact, since the length of one edit gap is about 0.25 mm, the area used for the edit gap in the four channels on one track is about 1.0 mm.

The reason why the audio signal of the same channel is recorded in the adjacent sector is for the independent editing of each channel. For example, in FIG. 1A, audio data A4 of the same channel is recorded in the top audio sector of each track.

As described above, in the case of recording a video signal at the center and an audio signal at both ends as shown in FIGS. 1A and 1B, the audio signal is divided into a plurality of sectors and recorded in one track. Is equal to the number of channels. Therefore, when the audio signal is recorded in N channels, the audio signal is divided into N audio sectors per track and recorded. Therefore, N edit gaps per track are required. Therefore, there is a problem that the magnetic tape can not be used effectively due to the edit gap.

In order to solve the above problems, an object of the present invention is to record 1 / M of the number of channels on one helical track when recording the N-channel audio signal on the magnetic recording medium by the number of N sectors, where M is Provided is an audio signal recording format of a VCR in which audio signals are recorded with a number of sectors of two or more).

Another object of the present invention is to divide an N-channel audio signal into N sectors on a magnetic recording medium and distribute it to a predetermined number of tracks so that the number of edit gaps present on one track is equal to 1 / M relative to the number of channels (N). Here, to provide an audio signal recording method and apparatus for a VCR capable of further recording an audio signal or a video signal by reducing the area of N and M by an integer of 2 or more).

In order to achieve the above object, in the audio signal recording format of the VCR according to the present invention, a video signal is recorded in a predetermined area on a track, and a predetermined number (N) of audio signals of a predetermined number (N) are recorded in the remaining area. In a magnetic recording medium divided into audio sectors and having an edit gap for independent editing between the video area and the audio area or between the audio and audio sectors, the number of the audio sectors on one track is the channel. The audio signal of N audio sectors is distributed to M tracks so as to be 1 / M relative to the number, thereby reducing the edit gap to 1 / M (where N and M are integers of 2 or more).

In the audio signal recording method of a VCR according to the present invention, a video signal is recorded in a predetermined area on a track, and audio signals of a predetermined number (N) of channels are divided and recorded in a predetermined number (N) of audio sectors in the remaining areas. An audio signal recording method for recording an audio signal on a magnetic recording medium having an edit gap for independent editing between the video region and the audio region or between the audio sector and the audio sector, wherein N channels from the audio signal source are recorded. A first data conversion process of converting an analog audio signal input into a digital signal into a digital signal; A storage step of storing N-channel digital signals in the first data conversion step; A second data conversion step of converting the signal stored in the storage step into a signal suitable for recording on the magnetic recording medium; And a recording control process of recording and controlling the audio signals of the N audio sectors converted in the second data conversion process to be divided into M tracks so that the number of audio sectors on the helical track becomes 1 / M with respect to the number of channels. In addition, the edit gap is reduced to 1 / M (wherein N and M are integers of 2 or more).

In the audio signal recording apparatus of the VCR according to the present invention, a digital video signal is recorded in a predetermined area on a track, and a digital audio signal of a predetermined number (N) of channels is divided into a predetermined number (N) of audio sectors in the remaining area. An audio signal recording apparatus for recording an audio signal on a magnetic recording medium which is recorded and has an edit gap for editing independently between the video region and the audio region or between the audio sector and the audio sector. A plurality of memory means for dividing and storing the data into N channels; And control means for distributing audio signals of N audio sectors stored in the plurality of memory means to M tracks such that the number of audio sectors on the one track becomes 1 / M relative to the number of channels. It is characterized by reducing the edit gap to 1 / M (where N and M are integers of 2 or more).

Hereinafter, an audio signal recording format, a recording method, and a device of a VCR according to the present invention will be described with reference to the accompanying drawings.

2 is a block diagram showing an embodiment of an audio signal recording apparatus of a VCR according to the present invention.

The configuration of an embodiment of the present invention comprises a plurality of analog / digital (A / D) converters 11-14, a plurality of A / D converters 11-14 for converting an incoming analog audio signal into a digital signal. A plurality of memories 21-24 configured to store audio signals converted into digital signals of the same number, and a recording processor for modulating audio signals stored in the plurality of memories 21-24 into signals suitable for recording on magnetic tapes ( 40, a plurality of heads 51-54 for recording a plurality of channel signals outputted from the crossroad distance section 40 in a predetermined audio region on a tape, a main clock signal Clock and a horizontal synchronization signal Hsync. To generate memory enable signals for enabling the plurality of memories 21-24, output the result to the enable terminals EN1-EN4 of the memories 21-24, and output the plurality of heads 51-24. Generate and enable head enable signals to enable Is the enable terminal to the control signal generating part 30 that outputs a (EN1-EN4) of the head (51-54).

Next, the operation of the audio signal recording apparatus shown in FIG. 2 will be described.

2, the first to fourth A / D converters 11-14, which input four analog audio signals from the audio source, convert the input analog audio signals into digital data suitable for recording. 4 Store in memory 21-24.

Source coding such as data compression may be performed before being stored in the first to fourth memories 21-24.

The audio data stored in the first to fourth memories 21 to 24 are converted into a signal form suitable for recording on magnetic tape by outputting only the output of the memory enabled by the memory enable signal to the recording processor 40. It is written on the magnetic tape through the four heads 51-54.

At this time, the recording processing unit 40 performs channel coding. As is widely known, the recording processing unit 40 modulates the signal into a signal suitable for recording, such as an EFM (Eight to Fourteen Modulation) signal.

The four heads 51-54 for recording the output of the recording processing unit 40 are constituted by four channel heads (head A, head B, head A ', and head B') as shown in FIG.

The four heads 51-54 are enabled in accordance with the head enable signal generated by the control signal generator 30, and record the output of the recording processor 40 in the audio sector determined on the track.

Here, the data of the first memory 21 is called A1, the data of the second memory 22 is called A2, the data of the third memory 23 is called A3, and the data of the fourth memory 24 is called A1. Let's say A4.

Referring to the process in which these data A1-A4 are recorded on the tape, first, control signals (memory enable signal, head enable signal) for controlling the input / output of the data are transmitted from the control signal generator 30 to FIGS. The output is as shown in Fig. 4b.

The control signal (head enable signal, memory enable signal) generated by the control signal generator 30 and input to the four heads 51-54 and the first to fourth memories 21-24 will now be described. Same as Instead of the control signal generator 30, a control signal may be generated by a system controller (not shown).

The rotational speed of the drum shown in FIG. 3 is 5400 rpm (radian per minute), that is, 90 rpm (radian per second). This means that the drum rotates three times per frame. Then, as shown in FIG. 3, when the drum rotates one time, two heads simultaneously generate two tracks. Therefore, one frame consists of 12 tracks, and one track consists of four audio sectors.

Accordingly, the half rotation time of the drum is 1/180 seconds, and the winding angle of the magnetic tape is θ because the angle at which the magnetic tape is wound on the drum is not 180 °. ,

t1 = 1/180 × θ / 180... … … … … … … … … … … … … … … … … … … (One)

Becomes

In addition, the memory enable signal for controlling the memory 21-24 is shown in FIGS. 4E to 4H at the beginning or end of the track generation time T1 corresponding to equation (1). Provided for a predetermined time x seconds, and the first memory 21 is enabled by a memory enable signal (Fig. 4e) generated at the beginning of the track generation time by the head A 51 and the head B 52. The second memory 22 is enabled by the memory enable signal (FIG. 4f) generated at the end of the track generation time by the head A 51 and the head B 52, and the third memory 23 ) Is enabled by the memory enable signal (FIG. 4g) generated at the beginning of the track generation time by A '53 and head B' 54, and the fourth memory 24 is head A '. (53), it is enabled by the memory enable signal (FIG. 4h) which occurs at the beginning of the track generation time by the head B'54. Here, the predetermined time x is the time corresponding to two audio sectors shown in FIG. 1A, for example, sectors A1 and A2 of the first track.

The audio signal recording operation will be described in more detail with reference to the above description as follows.

When the magnetic tape is wound around the heads A 51 and B 52 on the drum, the data stored in the first memory 21 is input to the recording processing unit 40 by the memory enable signal shown in FIG. 2E. The head enable signals shown in FIGS. 4A and 4B are supplied from the control signal generator 30 to the heads A 51 and B 52 so that data can be recorded on the magnetic tape.

Although the head A 51 and the head B 52 have an offset but perform a recording operation at substantially the same time, as shown in FIG. 7A, A1 data is simultaneously recorded in the lowest audio sector of two tracks.

Here, A1 data simultaneously recorded on two tracks may be odd data and even data of the first memory 21 output through the recording processor 40. When odd data of A1 data is recorded on one track, even data of A1 data is recorded on the other track.

As shown in FIG. 7A, after the audio signal A1 is recorded in a predetermined region of the lowermost audio sector, two channels of video signals stored in the video memory (not shown) are assigned to the head A 51 and the video sector. It is recorded by the head B 52.

When the uppermost audio sector on the helical track is reached again, the data of the second memory 22 is inputted to the recording processing unit 40 by the memory enable signal shown in FIG. 4f, so that the head A 51 and the head B 52 are located. By this, A2 data is simultaneously recorded on two tracks.

This memory enable signal (Fig. 4f) is generated after a predetermined time T3 has elapsed in the high period of the head enable signal (Figs. 4a and 4b), and is expressed by the following expression (2).

T3 = (1/180 × θ / 180-x)... … … … … … … … … … … … … … … … … … … (2)

When the odd data of A2 data is recorded on one track in the top audio sector as in the A1 data of the lowest audio sector, the even data of A2 data is recorded on the other track.

In this operation, when one helical track of magnetic tape is viewed, audio data A1 is first recorded in one sector, and video data is recorded for a predetermined time, and then audio data A2 is recorded.

Then, the time T2 at which the magnetic tape is not wound, that is,

T2 = 1 / 180- (1/180 × θ / 180). … … … … … … … … … … … … … … … … … … (3)

After the time T2 corresponding to equation (3) has elapsed, the data stored in the third memory 23 is input to the recording processing unit 40.

At this time, the head enable signal generated from the control signal generator 30 to record the audio signal on the magnetic tape is as shown in FIGS. 4c and 4d. It is supplied to head B'54.

Therefore, the third memory 23 is enabled only during the high period of the memory enable signal as shown in FIG. 4C, and the data A3 stored in the third memory 23 is stored in the head A '53 and the head B'. It is supplied to 54 and recorded in two tracks on magnetic tape.

After the video signal is recorded in the predetermined region of the video sector, the data of the fourth memory 24 is input to the recording processor 40. The fourth memory 24 is enabled during the high period of the memory enable signal shown in FIG. 4h, and data A4 stored in the fourth memory 24 is stored in the head A '53 and the head B' 54. FIG. By two tracks on the magnetic tape.

In this operation, the audio data A3 is recorded in the audio sector of the next two tracks of the magnetic tape by the head A '53 and the head B' 54, and after the video signal is recorded for a predetermined time, the audio data A4 is recorded. Is recorded.

5 is a block diagram of another embodiment of an audio signal recording apparatus of a VCR according to the present invention.

The configuration of FIG. 5 is based on the first to fourth memories 21-1 by the memory enable signals (FIGS. 4E and 4B) generated by the control signal generator 30 of FIG. 2 as compared with FIG. 24, respectively, while the first memory 121 and the third memory 123 are connected by the memory enable signals (FIGS. 6e and 6f) generated by the control signal generator 130 of FIG. The only difference is that they are enabled at the same time and enable the second memory 122 and the fourth memory 124 simultaneously by the memory enable signals (Figs. 6g and 6h).

The operation of FIG. 5 will not be described in FIG. 2 and will be described based on the relationship between the memory enable signal generated by the control signal generator 130 and the memory.

According to FIG. 5, the memory enable signal for controlling the memories 121-124 is shown in FIGS. 6E to 6H at the beginning or end of the track generation time T1 corresponding to equation (1). As described above, the first memory 121 and the third memory 123 are provided for the predetermined time x seconds, and the head A 161 and the head B 152 or the head A '153 and the head B' 154 are provided. Is enabled by the memory enable signals shown in FIGS. 6E and 6G at the beginning of the track generation time of the tracks, and the second memory 122 and the fourth memory 124 are the head A 151 and the head B. FIG. 152 or at the end of the track generation time of head A '153 and head B' 154 is enabled by the memory enable signals shown in FIGS. 6f and 6h.

That is, when magnetic tape is wound around the heads A 151 and B B 152 on the drum, the data stored in the first memory 121 and the third memory 123 is input to the recording processing unit 140. From the control signal generator 130, the head enable signals shown in FIGS. 6A and 6B are supplied to the head A 151 and the head B 152, and the output of the third memory 123 is connected to the magnetic tape. It is recorded on the track.

After the audio signals A1 and A3 are recorded, video signals of two channels stored in the video memory (not shown) are recorded by the head A 151 and the head B 152 in a predetermined video sector.

Thereafter, when data stored in the second memory 122 and the fourth memory 124 are input to the recording processing unit 140, the head A 151 records the output of the second memory 122 on the track of the magnetic tape. The head B 152 records the output of the fourth memory 124 on the track of the magnetic tape.

When the tape is wound around the head A '153 and the head B' 154, the above-described operation is performed.

Here, the head A 151 and the head A '152 record data of the odd channel, that is, A1 and A3 on the magnetic tape, and the head B 152 and the head B' 154 are data of the even channel, Record on A2 and A4 ruled magnetic tape. The format of the tape recorded in this way is as shown in FIG. 7B.

The above operation is an example of recording four audio channel signals on magnetic tape. When recording audio signals on four channels, the number of audio sectors included in one track is two and the edit gap is two. Therefore, the signal can be further recorded by an area corresponding to two edit gaps.

For example, in a system where the shortest recording wavelength is 0.6 vm and the length of one edit gap is 0.3 mm, the audio signal is recorded in eight channels, that is, the tape shown in FIG. 1b is recorded as shown in FIG. In this case, about 4 x 0.3 mm / (0.6 vm / 2 bit) = 4000 bits of data can be recorded on one track.

When the audio signal is recorded as N channels on the helical track as described above, the number of edit gaps is reduced because the audio color is reduced to N / 2, so that the signal is recorded in the N audio sectors. Compared to this, it is possible to record more video or audio signals in the reduced edit gap area.

7C shows a tape format in which signals of eight audio channels are recorded on a helical track, and has four edit gaps in one track. Conventionally, although eight data gaps are configured in one track, the present invention means that the number of edit gaps is reduced by half, thereby ensuring a usable data recording area.

The relationship between the number of audio sectors and the number of channels mentioned in the above embodiment is expressed as follows.

Number of audio sectors = number of channels / M (where M is an integer of 2 or more). … … … … … … … … … (4)

Although the description of the present invention has been described with respect to four channels and eight channels, it is not limited thereto.

In addition, although N / 2 audio sectors are set per track when using N channels according to the operation of the present invention, the present invention is not limited thereto, and the number of audio sectors configured per track may be inversely proportional to the number of channels. have. For example, when the memory enable signal and the head enable signal generated from the control signal generator shown in FIG. 2 shown in FIG. 2 are adjusted, the audio is set per track such as N / 4 or N / 8. The number of sectors can vary.

As described above, the audio signal recording format and recording method of the VCR according to the present invention, and a device for dividing the audio signal of N channels into N sectors and distributing them into a predetermined number of tracks to record audio sectors on one track. As the number is reduced to 1 / M with respect to the number of channels, the audio or video signal can be recorded as much as the edit gap area reduced, so that the recording capacity can be improved.

Claims (13)

A video signal is recorded in a predetermined area on the helical track, and audio signals of a predetermined number (N) of channels are divided into a predetermined number (N) of audio sectors and recorded in the remaining area, and between the video area and the audio area or audio. In a magnetic recording medium having an edit gap for independent editing between a sector and an audio sector, audio signals of N audio sectors are tracked in M tracks such that the number of audio sectors on one track is 1 / M relative to the number of channels. Recording format of an audio signal of a VCR, wherein N and M are integers of 2 or more. A video signal is recorded in a predetermined area on the helical track, and audio signals of a predetermined number (N) of channels are divided into a predetermined number (N) of audio sectors and recorded in the remaining area, and between the video area and the audio area or audio. An audio signal recording method for recording an audio signal on a magnetic recording medium having an edit gap for independent editing between a sector and an audio sector, wherein an analog audio signal input through N channels from an audio signal source is converted into a digital signal. Converting first data; A storage step of storing digital signals of N channels in the first data conversion step; A second data conversion step of converting a signal stored in the storage process into a signal suitable for recording on the magnetic recording medium; And a recording control process of recording and controlling the audio signals of the N audio sectors changed in the second data conversion process into M tracks so that the number of audio sectors on the one helical track becomes 1 / M with respect to the number of channels. And the editing gap is reduced to 1 / M (wherein N and M are integers of 2 or more). The method of claim 2, wherein the number of audio sectors is 1/2 of the number of channels. The audio signal recording method of claim 2, wherein in the storing process, audio signals of N channels are stored as much as Mx audio sectors than reference audio sectors. 3. The audio signal recording method of claim 2, wherein in the recording control process, audio signals of the same channel are recorded in adjacent sectors on the magnetic recording medium for independent editing of each channel. A digital video signal is recorded in a predetermined area on the track, and a digital audio signal of a predetermined number (N) of channels is divided into a predetermined number (N) of audio sectors in the remaining area, and recorded between the video area and the audio area or the audio. An audio signal recording apparatus for recording an audio signal on a magnetic recording medium having an edit gap for independent editing between a sector and an audio sector, comprising: a plurality of memory means for dividing and storing the digital audio signal into N channels; And control means for distributing audio signals of N audio sectors stored in the plurality of memory means to M tracks such that the number of audio sectors on the one track becomes 1 / M relative to the number of channels. An audio signal recording apparatus, wherein N and M are integers of 2 or more, characterized in that the edit gap is reduced to 1 / M. 7. The recording apparatus according to claim 6, wherein the recording control means comprises: a plurality of heads composed of N pieces on a drum; Recording processing means for processing an N-channel audio signal output from the plurality of memory means into a signal suitable for recording on a magnetic recording medium; And control signal generation means for generating a memory control signal for controlling the audio signal to be read from the corresponding memory of the plurality of memory means and a head control signal for enabling the heads. Device. 8. The VCR of claim 7, wherein the recording control means records an audio signal of the same channel by the N / M heads on the magnetic recording medium for independent editing of each channel. Audio signal recording device. 7. The audio signal recording method of a VCR according to claim 6, wherein audio signals of N channels are stored as much as M sectors of audio sectors than M audio sectors. 8. The memory control signal generated by the control signal generating means is a signal that is activated for an audio sector period of M times at a predetermined time point of the actual period in which the magnetic recording medium is wound on the head-mounted drum. An audio signal recording apparatus of a VCR. 8. The VCR of claim 7, wherein the head control signal generated by the control signal generating means is a signal in which the N / M heads are simultaneously enabled only during the actual period in which the magnetic recording medium is wound on the drum. Audio signal recording device. A video signal is recorded in a predetermined area on the helical track, and audio signals of a predetermined number (N) of channels are divided and recorded in a predetermined number (N) of audio sectors in the remaining area, between the video area and the audio area or the audio. An audio signal recording method for recording an audio signal on a magnetic recording medium having a data gap for independent editing between a sector and an audio sector, wherein the audio signal input from the audio signal source to the N channel is converted into a digital signal. Digital / analog conversion means; N memory means for storing the digital audio signal of the N channel; And N heads for recording the outputs of the N memory means in a predetermined audio sector. Alternatively, while the N / 2 heads are enabled, the remaining N / 2 heads include head enable signals for disabling and control signal generating means for generating respective memory enable signals of the N memories. Thus, the edit gap is reduced to 1/2, and the N / 2 heads simultaneously record data of one selected memory among the N memories in a predetermined audio track to record audio signals of the same channel in adjacent sectors. An audio signal recording apparatus of a VCR. 13. The control signal generating means according to claim 12, wherein the control signal generating means generates a first memory enable signal for simultaneously enabling memory of an odd channel and a first memory enable signal for enabling memory of an even channel simultaneously. And recording the output of the memory of the channel with the audio sector predetermined by the N / 2 heads.