KR100222471B1 - A long time recording method of only recording vtr - Google Patents

Abstract

The present invention relates to a long-term recording method of the recording dedicated VTIAL, a composite vector according to the tape advance speed and the inclination angle and rotational speed of the head drum in the normal playback direction, that is, the scanning angle and speed On the basis of, by advancing the tape to 1 / N times, and setting the inclination and speed of the head drum so that the scan angle and speed according to the composite vector are not deformed, N times is recorded in the general VTial. In accordance with the angle of the scanned scan line to be scanned, the playback quality is reproduced along the recorded scan line N times from the playback head during playback, so that the playback quality is improved.

Description

Long time recording method of recording VRT

The present invention relates to a long-time recording method of the recording dedicated VTI, in particular, the speed of the tape is 1 / N times, by adjusting the inclination of the head drum and the scanning speed of the head so that the angle of the scanning line is not deformed, N times, Since there is no deformation of the scan line during recording, the present invention relates to a long time recording method of a recording-only VTI that can improve image quality when played back with a general VRT.

A schematic playback method according to a general N-fold recording is shown in FIGS. 1A and 2B. As shown in FIGS. 1A and 2B, an image data detection unit 70 which is a partial data intersecting an N-fold recorded recording line and a normally reproduced scanning line, and the image A signal presence detection unit 71 for receiving a signal detected by the data detection unit 70 to determine the presence of a signal and outputting a pulse according thereto, and the image data detection unit 70 according to the pulse output from the signal presence detection unit 71. A multiplexer 72 for dividing the signal detected by the < RTI ID = 0.0 >), a memory 73 for storing the signal divided by the multiplexer 72 < / RTI > and a pulse signal from the signal presence detecting unit 71 output a sequential flashing signal. It consists of a ring counter (74).

Herein, the operation of the reproducing method according to N times recorded recording having the above configuration will be described.

First, as shown in FIG. 1A, a scanning line recorded at an N-time recorded with a predetermined angle, that is, a scanning line 1, 2, 3, 4, 5, .... ) And the scan line produced at this time are detected from the image data detector 70, which is a portion where the scan lines a, b, .... formed to intersect. In outlined description, the playhead for reproducing the recorded content scans track A, and then scans track B.

At this time, the A track signal detected from the playhead is N times recorded, and the 'ga' portion of the scan line 1 is detected first, and the 'na' portion of the scan line 2 is detected, and then the 'multi' portion of the scan line 3 is detected. Will be detected. In addition, while scanning the track B, the playhead detects the 'ga' portion of the scanning line 3 recorded N times more, detects the 'na' portion of the scanning line 4, and then detects the 'multi' portion of the scanning line 5. will be. Each data detected by such a detection method is combined and reproduced through a predetermined circuit, which will be described below with reference to FIG. 1B.

When the above-described N times recorded data is reproduced at the normal speed, the signal according to the signal flows into the signal presence detection unit 71 to control the on / off of the output signal according to the noise removal and the presence of the input signal. . In addition, the reproduction signal introduced into the signal presence detection unit 71 is simultaneously introduced into the multiplexer 72 to receive a signal output from the signal presence detection unit 71. This is for the pulse signal output from the signal presence detecting unit 71 to sequentially output the reproduction signal applied to the multiplexer 72. The sequentially output reproduction signals are stored through the memory 73. In this case, the data to be stored should be stored in the order of the recorded data by N times. This operation uses a ring counter 74 that receives the pulse signal output from the signal presence detection unit 71 and sequentially flashes according to the input pulse signal.

Then, the data of the 'ga' portion detected by the number 1 scan line recorded N times is designated as address 1 by the multiplexer 72 and the first part of address 1 is selected from the ring counter 74. . In this portion, some of the data of the number 1 scan line recorded as the N times is stored. In addition, it is determined that the data of the 'b' portion of the second scanning line detected by the playhead through the track A is the second input signal from the signal presence detecting unit 71. Due to this, the data of the 'I' part of the scan line 2 is transmitted to the address 2 through the multiplexer 72, and the ring counter 74 selects the second part of the address 2 to 'B' of the scan line 2. The data corresponding to the part is stored.

Thereafter, the reproduction scan line of track A detects 'multi' among the number 3 scan lines recorded N times, and the reproduction scan line moves to track B and detects 'ga' of number 3 scan lines recorded N times. This allows the multiplexer 72 to transmit the detection data to address 3 of the memory 73, while the ring counter 74 selects the third part of address 3, and then selects the first part to N times. Some of the scanning lines 3, which are recorded, are stored.

The data stored in this manner is output by selecting the address of the memory 73.

However, the above configuration causes a difference in the forming angle between the scan line formed from the tape speed of 1 / N times the recording rate and the scan line scanned in the normal playback as the number of times is increased, so that playback is performed regardless of the forming angle of each scan line. Done. As a result, after partially combining the image data detected in hardware, the combined final image signal is output to reproduce the recorded image. Then, the output video signal is degraded because only a portion of the recorded signal is stored after being stored N times, and thus it is difficult to reproduce important scenes captured by a closed surveillance camera that mainly utilizes N times recording. have.

Accordingly, the present invention has been made to solve the above problems, by changing the inclination of the head drum and the speed of the head drum according to the tape speed of 1 / N times so that the angle of the recording line recorded as N times more deformed N Since no distortion of the scan line occurs during double-recording recording, it plays back along the scan line recorded N times more from the playhead when playing with a normal VTial, thereby providing a long-term recording method of the recording-only VTIAL to increase the image quality during playback. Has its purpose.

The present invention for achieving the above object, on the basis of the tape running speed and the tilting angle and the rotational speed of the head drum relative to the tape running direction in the normal playback, that is, based on the scanning angle and speed, The tape advancing speed is 1 / N times, and the tilt and speed of the head drum are reset so that the scanning angle and speed are not deformed according to the composite vector.

1A is a diagram illustrating a schematic method for normal reproduction of conventional N times recorded data;

1B is a view showing a configuration according to the schematic method of FIG. 1A,

2 is a view showing the inclination and the speed of the head drum to be calibrated according to the present invention.

* Explanation of symbols for main parts of the drawings

V ₁ : Scanning line during playback and recording

Vs´: Head drum rotation speed for 1 / N times recording

α: slope of the head drum during normal playback

α´: Tilt of the head drum during 1 / N times recording

β: Scanning line angle during playback and recording

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

First, as shown in FIG. 2, the configuration for setting the tilt and speed of the head drum according to the present invention includes a fixed position point of the head for displaying the tape running speed and the tilt and rotation speed of the head drum at relative speeds. H), the relative speed Vt in the advancing direction of the tape around the fixed position point H of the head, and the absolute speed Vs scanned by the head based on the fixed position point H of the head. ) And the head tilt α showing the inclination angle of the head drum with respect to the absolute speed Vs, the absolute speed Vs of the head and the relative speed Vt according to the advancing direction of the tape. And a composite vector V ₁ , which is illustrated and described, and an angle formed by the composite vector V ₁ , that is, the scan line angle β.

On the other hand, when the tape speed Vt is 1 / N times based on such a configuration, the inclination angle of the head drum and the rotation speed of the head drum are set as follows so that the scanning line angle β is not deformed. .

When the tape speed (Vt / N) at the time of recording is set to 1 / N times the relative speed (Vt) according to the progress of the tape around the fixed position point (H) of the head, the tape speed (Vt) at the time of recording is set. / N) and the new rotational speed (Vs') of the head drum so that the composite vector (V ₁ ) is not deformed. This assumes the scalar amount of the relative speed Vt according to the progression of the tape as the line segment 'D' shown in FIG. 2, and the tape speed Vt / N at the time of recording which is 1 / N times the relative speed Vt. Assuming the scalar amount of) as the line segment 'A', and setting the scalar component 'B' using the absolute speed (Vs) of the head and 'C' and 'D', the rotational speed (Vs') First, the definition of line segment is as follows.

A = | Vt | / N = | Vt '|

B = | Vs | COS (α)

C = | V ₁ | SIN (β)

D = | Vt |

B + D = A + E

E = D + B-A

In the relationship between the line segments defined as above, the value of E is expressed by the following equation.

[Equation 1]

Then, the rotation speed (Vs') of the head drum using the value of the set line segment E, the value of the C and the head tilt α and the scan line angle β, which are already set as constants, can be obtained.

It is represented by Equation 2 more specifically.

[Equation 2]

Then, as described above, the composite vector formed from the traveling speed Vt of the tape by the head tilt α, which is the inclined angle of the head drum, and the rotation speed Vs of the head rotating with the head tilt α, V ₁ ) is not deformed, and the rotational speed Vs' of the head drum is set as the traveling speed Vt decreases by 1 / N times.

Meanwhile, a process of setting a new head tilt α ′, which is an inclination angle of the head drum according to the rotation speed Vs' of the head drum, is as follows.

By the head tilt α 'is expressed by the equation (3).

[Equation 3]

∴

The velocity and the tilted angle of the head drum thus obtained are to prevent deformation of the scan line during recording. Therefore, when recording at the rotational speed (Vs ') and the head tilt (α') of the reset head drum, the recording is performed at the scanning line angle (β) scanned from the general VTial, so that it can be reproduced with the general VTal. Will be done.

As described above, in the present invention, when the recording speed for recording N times, that is, the tape speed is reduced by 1 / N times, the head scan angle during normal playback after setting the velocity vector of the tape thus formed is not changed. By re-adjusting the head speed and the tilt angle of the head drum during recording, N times the recorded tape is played back so that the angle of the recording scan line and the angle of the playback scan line can be matched to improve the playback quality. It is possible to regenerate with thial, which has the effect of widening the range of application.

Claims (3)

In VTI used exclusively for recording, When the rotational speed of the head drum according to the recording of VTI is reset to Vs ', and the tape speed is reduced by 1 / N times by resetting the tilt of the head drum to α', the number of times recorded is recorded. A long time recording method of a recording dedicated VTIAL, wherein the angle coincides with the angle of the reproduction scan line during normal reproduction. The method of claim 1, wherein the rotational speed Vs' of the head drum is expressed by the following equation;

The method of claim 1, wherein the gradient α 'of the head drum is expressed by the following equation;

∴

Images