JPS60138783A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To eliminate distortion at the edition point by recording the 1st and 2nd CH data in four channels to an odd number field in one frame and inserting the 2nd CH data delayed by one field duplicatedly to an idle channel CH inserted with the 3rd and 4th CH. CONSTITUTION:If the 1st and 2nd CH data inserted to the 3rd and 4th CH of a PCM data 10a and the 1st and 2nd CH data of a field 10b are equal, an output 18a is extracted. The data recorded on the 3rd and 4th CH of the preceding one field 10a is reproduced with skipping, and when the data are not equal and no correlation exists, the PCM data included in the 1st field 10a is extracted to the output 18b and the PCM data included in the next 2nd field is extracted from the output 18c. After both the data are applied with weighting of a reciprocal by variable resistors 19, 20 by a inverse interlocking coefficient circuit 17 and subject to cross fade, an edition output 22 is extracted via an adder circuit 21.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a magnetic recording/reproducing device, and in particular to a magnetic recording/reproducing device, and in particular, when data is all-helically recorded on a magnetic tape of a video recorder (hereinafter referred to as VTR), an even number (or Record the first and second channel data of the four channels in the (odd number) field, and insert all the first and second channel data delayed by one field overlappingly into the empty channel where the third and fourth channel data are inserted. This article is related to a magnetic recording/reproducing device designed to do this.

BACKGROUND OF THE INVENTION 2. Description of the Related Art and Problems There are already known magnetic recording and reproducing apparatuses that helically record (reproduce) pulse code modulated (hereinafter referred to as PCM) signals on a VTR. FIG. 1 shows a PCM audio data track 2a recorded helically on a magnetic tape 1, for example.
2b -------2n All shown, but since the continuous audio data uses multiple rotating heads, the first track 2a and the second track are actually continuous audio data. Between track 2b of the eye, similarly between tracks 2b and 2c°=-
-----) Discontinuity occurs between racks 2n-1 and 2n. During such recording and playback, each track 2a, 2b
, 2cm------" 2n edge part 3.4
There is a problem in which there is a high probability that signal dropouts will occur.Furthermore, these PCM audio data tracks 2
a, 2b, 2c ------- When recording a 2nk television signal, one frame 7a consisting of an odd field 5a and an even field 5b between vertical synchronizing signals V and the next When performing editing such as splicing the PCM data of frame 7b at the position shown by reference numeral 6, the PCM data 5b and data 5cFi are combined as shown in FIG.
Since the data is uncorrelated, editing points 8 (seams) cause signal discontinuity and clicks, etc., and since it is a rotating head, speed control is not possible and crossfading is not possible.

Purpose of the Invention The present invention has been made in view of the above-mentioned drawbacks, and its purpose is to record PCM data using a special method using a rotating VTR, and to easily perform cross-fading during playback. 15. Arrangement of the Invention and the above objects according to the present invention provide a device with four channels 'lk2
In a magnetic recording/reproducing device used in the channels, the first and second channel data of the four channels are sequentially recorded in chronological order in the odd-numbered fields and even-numbered fields in one frame, and the data of the fourth channel of the odd-numbered fields are recorded. the third
Then, all of the first and second channel data of the even field are inserted with a one-field delay in the fourth channel data insertion part, and the third and fourth channel data of the even field of the next frame are also delayed by one field. This can be achieved by providing a magnetic recording/reproducing apparatus characterized in that odd-numbered first and second channel data are sequentially inserted.

Embodiments of the Invention Below, all drawings of the magnetic recording/reproducing apparatus of the present invention will be described in detail. FIG. 4 is a system diagram showing an embodiment of the PCM data recording apparatus of the present invention, and FIG. 5 is a waveform explanatory diagram. In FIG. 4, 9a, 9b, and 9c are first to third random access memories (hereinafter referred to as RAMs), and data for music information is converted into PCM and is stored in the first to third RAMs 9a. ,
The PCM audio data 10 supplied to the RAM 9b and RAM 9c is stored in the first RAM 9a as shown in FIG.
Similarly, channel data indicated by 11.21 of one field's worth of data 10a is sequentially recorded in the second RAM 9b as well, and channel data indicated by 1: and 21 of one field's worth of data 10b are sequentially recorded.

Next, 11 of the PCM data from the first RAM 9a
．． 21' (f- At the same time as reading and recording, the second
The first and second channel data 1a) 2 of the RAM 9b
2 is recorded as data 12' and 22' in FIG. 5 [F]). .

In this state, the third RAM 9c is empty, so the next (PCM data 15.23) is written into the second RAM 9b.
, 2i record one field as shown in FIG. 5(B), and at the same time, the first and second channel data Xi,
2* is read and recorded in the next field 10b as shown in FIG. 5e). In this state, the first RA
Since M9a is empty, the next (PCM data 14.24) is written to the third RAM 9c. The channel storage data I11, 2i'(l" is read and filled in the field 10c.
At the same time, data 14' and 24'i are recorded in the inserted portions of the third and fourth channels. At this time, the second RA
Since M9b is empty, data 1as2a following the first RAM9a is stored. By repeating this process, all of the first and second channel data in the previous part of one field are transferred to the third and second channel data in the previous part of the field, as shown in Figure 5 (CB). It becomes possible to insert and record 4 channels in a portion to be recorded.

As mentioned above, for example, P recorded on the magnetic tape of a VTR
When compiling commercial data into a drama collection, please use all the 6th factors and Figure 7 to describe in detail. Figure 6 is a system diagram of the playback editing device.
As shown in FIG. 3B, the data j'ti D is outputted from the data vTR 13 helically recorded using a rotary head on a magnetic tape and applied to the arithmetic circuit 16 via the buffer memory 14. Reference numeral 15 denotes an editing operation unit for performing editing operations.The output of the buffer memory 14 is given to a comparator circuit 18 in an arithmetic circuit 16, which includes a control unit for controlling the operation of the entire system. VTR within 18
PCM data in 1 field carried in the TV signal of 10a, data 1 of the 1st and 2nd channels inserted into the 3rd and ig 4th channel portion of 10a, ', 22' and the 1st and 2nd of field 10b. Channel data 111.
If 2+1 are equal, the output 18a becomes J49. The data Ig', 2i''!r recorded in the 3rd and 4th channel parts of the previous field 10a is skipped and reproduced, and the data 1g, 2g and 1.', 22' are not equal and have no correlation. If there is no PCM contained in the first field 10a
Data 1+i', 2tr' are taken out to output 18b,
PCM data 1g, 2 included in the following second field
m is taken from output 18c. Both of these data are transmitted to the ninth point by the inverse motion coefficient circuit 17 through variable resistors 19 and 20.
As shown in the figure, the weighting of the inverse coefficients is carried out in such a way that after all the weighting is carried out and crossfading is performed, all the editing outputs 22 are taken out through the adding circuit 21.

Effects of the Invention Since the present invention is configured as described above, it is possible to repeatedly record data on both edge portions of the tape, and interpolation when one edge is missing is not only simple, but also allows for rotational VT.
It has the feature that R data can be edited automatically and distorted sound can be effectively removed at the editing point.

[Brief explanation of drawings]

Figure 1 is a plan view of a magnetic tape showing tracks when recording PCM data entirely helically on a conventional rotary VTR, Figure 2 is a recording format when recording PCM data on a conventional VTR, and Figure 3. is a data diagram explaining the editing points of conventional PCM data, FIG. 4 is a system diagram showing the recording system of the magnetic recording and reproducing apparatus of the present invention, and FIGS. FIG. 6 is a system diagram showing the editing system of the magnetic recording/reproducing apparatus of the present invention, and FIG. 7 is a cross-fade signal waveform diagram at the editing point. 1...Magnetic tape 2a, 2b, 2cm---2n*"
) Rack 3.4... Φ edge part 5a... Odd number field 5b... Even number field 6.8... @ Edit point 7a
, 7b "e 17 ram period 9a, 9b, 9cm ***1st to 3rd RA
M100・PCM audio data 12...Controller 13...VTR14...Buffer memory 15@...Editing device 16...Arithmetic circuit
17... Inverse motion coefficient circuit 18... Comparison circuit 19.
20...Variable resistor 21@...Addition circuit

Claims (1)

[Claims] In a magnetic recording/reproducing device that uses four channels as two channels, the first and second channel data of the four channels are sequentially recorded in chronological order during the odd and even fields in one frame, and the third
And the 1st and 2nd channel data of the above-mentioned even field are inserted with a delay of 1 field in the 4th channel data insertion part, and the 3rd and 4th channel data of the above even field are inserted with a delay of 1 field of the next frame. A magnetic recording/reproducing device 0 characterized in that the odd-numbered first and second channel data are sequentially inserted.