KR100192346B1 - Speed change device for a digital vcr - Google Patents

Abstract

Since the shift playback apparatus of DVCR has been disclosed, it is difficult to shift playback if the shift data is not accurately recorded on the helical track of the tape, and the multiplexing becomes very complicated because the recording positions of the shift guitar must be recorded differently. To solve this problem, first, the shift data recorded at the same position on the tape track by the helical head when the digital video signal is recorded can be easily reproduced by using the linear head and the MPEG digital video signal can be recorded and reproduced. In this case, all or part of the I frame serving as the reference image of all the images is detected and divided, and the divided data is recorded at the same position of each helical track. The multiplexing of the data is very simple.

Second, when the MPEG digital video signal is input, a part or all of the I frames are detected and divided, and recorded at the same position of each helical track, but a large number of I frames are reproduced to realize a natural shift image.

Description

DIGITAL V Seed's Shifting Playback Device

1 is a track configuration diagram of a tape according to the prior art.

2 is a block diagram showing a shift data recording and reproducing apparatus of a DVCR according to a first embodiment of the present invention.

3 is a track configuration diagram of a tape according to the present invention.

4 is a block diagram showing a shift data recording and reproducing apparatus of a DVCR according to a second embodiment of the present invention.

5 is a block diagram showing a variable speed data recording and reproducing apparatus of a DVCR according to a third embodiment of the present invention.

6 is a block diagram showing a shift data recording and reproducing apparatus of a DVCR according to a fourth embodiment of the present invention.

7 is a block diagram showing a variable speed data recording and reproducing apparatus of a DVCR according to a fifth embodiment of the present invention.

* Explanation of symbols for main parts of the drawings

11 input / output unit 12 format forming unit

13: shift regeneration processor 14, 24, 34, 47: switching unit

15, 25, 35, 46: control unit 16: recording / playback processing unit

17: rotating head drum 21, 31, 41: data processing unit for normal reproduction

22, 32, 42, 45, 64: storage 26, 36, 48: recording

23: variable speed reproduction data processing unit 27, 37, 49: tape running speed changing unit

28, 38, 50: Playback unit 29, 39, 52: Deformatting unit

33: I-frame detection and storage 43, 63: I-frame detection

44: I-frame data reduction unit 51: playback output amplifier

61: I-frame start code detection unit 62: VLD

65: packetization and sync block format unit

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to DVCR, and more particularly, to a variable speed playback apparatus for DVCR.

In recent years, digital broadcasting signals have been started or attempted to be started by US direct TV and ecostars.

In Europe, digital defense by DVB and in Korea is on the verge of inception.

Such digital broadcasting normally transmits a digital video signal based on the MPEG standard.

As described above, a magnetic recording and reproducing apparatus which attempts to record such a digital signal in the digital broadcasting era is being advanced.

As an example, Hitachi of Japan has developed an apparatus for recording / reproducing digital signals of Direct Dirk TV of the United States, and JVC has suggested a recording format of a tape.

In general, the speed regeneration of the DVCR is shown in FIG. 1, so that the rotational speed of the drum is the same as the normal regeneration, but the tape feed speed of the capstan motor remains in an accelerated state so that the head forms a trajectory across the track.

[0003] A variable speed reproduction method of a DVCR that shifts and reproduces I-frame data at a high speed without changing the arrangement state of the I-frame data recorded on the tape has been filed in Japanese Patent Application No. 94-16387.

In the variable speed regeneration method of the above-described filed DVCR, the normal regeneration step of performing a normal regeneration function to the end of I-frame and the skip speed of accelerating and decelerating the feed rate of the capstan motor for a predetermined time are performed. The shift image is reproduced by repeatedly performing the Skip) step.

However, the variable speed reproduction method of the previously filed DVCR also has the following problems.

Capstan motor control for precisely detecting the position of the I-frame recorded on the tape to increase the temporal update rate of the reproduced I-frame to reproduce a high-quality shift image, and controlling the time of the normal playback and skipping steps. Means were required, and when the time of normal playback and skipping step is controlled at a fixed interval because the recording position of I-frame is changed according to the contents of programs recorded on the tape, that is, sports, movies, events, etc. The reproduction quality was greatly changed according to the recorded data program, and a high quality shift image could not be expected.

In addition, the track structure and head trajectory of the tape for shift reproduction of a DVCR using a conventional 1 / 4-inch tape are shown in FIG.

According to FIG. 1, a plurality of partial shift data I1, I2, I3 are recorded on a helical track, and a head trace is recorded according to the double speed reproduction mode (3, 5, 7, ... double speed). By reproducing all the partial shift data existing in the E-frame, a single I frame is created to implement double speed reproduction.

That is, as shown in FIG. 1, I = I1 + I2 + I3.

However, the conventional speed reproducing apparatus must accurately record the shift data (I1, I2, I3) into a predetermined position on one helical track, and accurately record the recording position of the partial data during the shift reproduction.

Therefore, there is a problem that the implementation of the shift reproduction is very difficult as the shift tracking is likely to be wrong due to tape degradation, sagging tape, system instability, and the like.

Then, as shown in FIG. 1, the shift data recording positions must be recorded differently on each track, and there is another problem in that the multiplexing for this is very complicated.

In addition, conventionally, the shift data is recorded on a helical track for shift reproduction only, and the partial shift data of the same video is repeatedly recorded on one track when recording data for executing various speeds (3, 5 times ...). There is another problem that the use time of the tape is shortened.

Accordingly, the present invention has been made to solve the above-mentioned problems according to the prior art, and an object of the present invention is to linearize shifting data recorded at the same position on a tape track by a helical head when recording a digital video signal. The present invention provides a variable speed reproduction apparatus for a DVCR that implements variable speed reproduction using a head.

In addition, another object of the present invention is to detect and divide an I-frame in a DVCR for recording and reproducing an MPEG digital video signal, and to record the divided data at the same position of each helical track, using a linear head for shift reproduction. The present invention provides a variable speed reproduction apparatus of a DVCR that implements variable speed reproduction.

In addition, another object of the present invention is to detect and divide an I-frame in a DVCR for recording and reproducing an MPEG digital video signal, and to record at the same position of each helical track, but to record many I frames. Disclosure of the Invention The present invention provides a DVCR shift reproducing apparatus that records a reduced amount of data and reproduces a natural shift image by reproducing many I frames during shift regeneration.

In order to achieve the above object, the apparatus for shift reproducing of a DVCR according to the present invention records the shift data at the same position of the helical track and the human helical track of the tape and detects the shift data by using a linear head. It features.

Another feature of the present invention for achieving the above object is to detect an I-frame having data capable of realizing one complete image in a DVCR for recording a digital signal according to the MPEG standard, and It is characterized in that the amount of data is reduced to reduce the amount of shift data and the data is recorded in the shift data recording area.

Another feature of the present invention for achieving the above object is characterized in that the shift data recorded by the helical head is reproduced by the linear head having the same azimuth angle, instead of being reproduced by the helical head during shift reproduction.

Hereinafter, a shift regeneration device of a DVCR according to the present invention will be described with reference to the accompanying drawings for each embodiment.

(First embodiment)

2 is a block diagram showing a variable speed playback apparatus for a DVCR according to a first embodiment of the present invention. The configuration according to the present embodiment will be described below.

An input / output unit 11 for receiving a digital signal of an input digital broadcast signal or outputting a reproduced digital signal; A format forming unit 12 for converting the digital data input in the recording mode or the reproducing mode into a data format corresponding to the recording format of the tape, and constituting output data during reproduction; A shift playback processing unit (13) for detecting shift reproduction data for shifts only among the data compressed and configured by the format forming unit (12), temporarily storing the detected data, and then forming the packet into a corresponding format; A switching unit 14 for multiplexing the data output from the format forming unit 12 and the shift reproducing processing unit 13 in accordance with an output timing control signal and de-multiplexing upon reproduction of the recorded data; A recording / reproducing signal processor (16) connected to the switching unit (19) for performing a series of signal recording or reproducing processes including modulation or demodulation of a digital signal; The output timing signal and control means 15 for providing a traveling speed control signal of the tape 18 at the time of reproduction and controlling the entire system.

The format forming unit 12 packetizes the data in a format recorded on the tape and a data format unit 12a for generating information such as error correction of input data and sub information to be recorded on the tape. It also comprises a tape format section 12b for issuing recording timing.

The operation of the apparatus for reproducing video recording of a DVCR according to the present invention configured as described above is as follows.

First, the operation at the time of recording will be described.

The digital broadcast signal transmitted from the digital broadcast signal source is received by the integrated receiver decoder (IRD) and input to the data format unit 12a of the format forming unit 12 through the input / output unit 11.

The data format section 12a corrects an error of the input digital data, generates additional information to be recorded, inputs it to the tape format section 12b, and outputs a memory in which the data is temporarily stored and output.

The tape format unit 12b packetizes the input digital data into a format recorded on the video tape 18, generates recording timing, and performs signal processing such as modulation to record / reproduce through the switching unit 14. To the processing unit 16.

The shift regeneration processing unit 13 detects shift data from the signal output from the data format unit 12a and formats the detected shift data to be recorded on the tape 18 and applies it to the switching unit 14.

At this time, the control unit 15 outputs the timing control signal to the switching unit 14 so that the normal reproduction data and the detected shift data output from the tape format unit 12b can be recorded at a predetermined position on the tape track. ) Is applied to the recording / reproducing signal processor 16 in accordance with the recording timing control signal.

The recording / reproducing processor (! 6) receives the data output from the switching unit (14) and outputs the helical recording signal. The helical head (a) records the shift data and the normal reproduction data in accordance with the recording timing signal. To write in position.

The above-described shift data is recorded using the helical head a in the same position of each helical track and a plurality of adjacent helical tracks as shown in FIG.

On the other hand, the operation of shifting reproduction of the recorded data will be described.

When the user applies a shift mode (various speed mode signal) signal to the controller 15, the controller 15 increases the running speed of the tape 18 according to the speed mode.

At this time, the linear head 19 reads the shift data recorded on the track of the linear head 19 and outputs it to the recording / reproducing processor 16.

Here, the azimuth angle of the linear head 19 is configured to be substantially the same as the angle recorded in the helical head a for shift data detection.

The recording / reproducing processing unit 16 which receives the shifting data is outputted to the shifting / playing processing unit 13 through the reverse path during the recording, and extracts only the shifting screen from the shifting data to the input / output unit 11. It is displayed on the TV screen.

At this time, during shift reproduction of the shift data, the shift data on the helical track at the same position where the shift data is recorded is reproduced using the linear head 19, as shown in FIG.

Second Embodiment

FIG. 4 is a block diagram of a variable speed playback apparatus for a DVCR according to a second embodiment of the present invention. The configuration of the present embodiment is as follows.

A normal reproduction data processor 21 receiving an input digital broadcast signal and adding an error correction code and additional information (sub-code) for the digital signal to a sync block format; A storage unit 22 for temporarily storing the sync block format and outputting the sync block format according to a control signal; A shift data processor 23 for extracting shift data from the input digital broadcast signal and outputting the shift data according to one control signal; A switching unit 24 for selectively outputting the normal reproduction data and the shift data according to an output timing control signal; A recording section 26 for recording the data output by the switching section 24 on a tape using a helical head; A control unit 25 for providing the one control signal and the output timing signal and generating a tape travel speed change signal when a user applies a shift mode (various speed mode) signal; A tape running speed changing unit 27 for changing the running speed of the tape according to the tape running speed changing signal of the controller 25; A reproducing unit 28 for reproducing the shift data recorded by the recording unit 26 using a linear head; And a deformatting unit 29 which deformats the shift data reproduced by the reproducing unit so as to display the shift data reproduced.

Here, the shift reproduction data processing unit 23 includes an extraction unit for extracting the shift reproduction data and a storage unit for temporarily storing the extracted data.

First, the operation of the digital image proxy in the second embodiment will be described.

The digital broadcast signal transmitted from the digital broadcast signal source is received by the IRD and input to the normal playback data processor 21 and the shift playback data processor 23 through the input / output port.

The normal reproduction data processing unit 21 corrects an error of the input digital data, generates additional information to be recorded, converts it into a sync block format, temporarily stores it in the storage unit 22, and then inputs it to the switching unit 24. .

The shift reproducing data processor 23 extracts all or a part of the shift data for shifting from the compressed digital video signal to be input to the switching unit 24.

The normal reproduction data and the shift data applied to the switching unit 24 are input to the recording unit 26 in accordance with the output timing control signal of the control unit 25.

The recording section 26 records the applied data at the same position on the helical track of the tape by using the helical head.

The operation in shift reproduction of the recorded data is as follows.

First, when the control unit 25 applies a change signal of the running speed of the tape according to the double speed mode to the tape running speed changing unit 27 according to the double speed mode, the shift data recorded at the same position of the helical track is converted into a third position. As shown in the figure, the reproduction section 28 reproduces using the linear head.

The reproduced shift data is deformatted by the shift data deformatting unit 29 and displayed on the TV screen.

At this time, the speed mode is to change the running speed of the tape according to the selected speed mode by the user's key input.

Therefore, in the second embodiment of the present invention, the shift data for shifting during reproduction are extracted from the input digital video signal and recorded at the same position on the helical track using the helical head, and at the same position on the helical track during reproduction. The shifted data can be reproduced using a linear head.

(Third Embodiment)

FIG. 5 is a block diagram of a variable speed playback apparatus of a DVCR for inputting an MPEG digital video signal according to a third embodiment of the present invention, and the same elements as those of the second embodiment of FIG. 4 will be omitted.

At this time, in the third embodiment, the input signal is an MPEG digital signal, and the shift data processing unit 23 according to the second embodiment is an I-picture frame which becomes a reference image of all images among the input MPEG image data. Only the configuration of the I-frame processor 33 which detects and processes (Intra Picture Frame) only is different.

Therefore, the I-frame is input to the switching unit 34 by detecting all or part of the I-frame among the input MPEG signals, and the applied I-frame is applied to the output timing control signal of the control unit 35. To the recording unit 36 accordingly.

Here, when the input signal is an MPEG signal, an I-frame serving as a reference image of all images exists in the MPEG signal, and the other B and P frames are frames indicating only the amount of video change.

The I-frame is about 1.3M as data that can constitute one complete picture.

Within this I-frame there are multiple encoded macro blocks.

Therefore, no problem occurs in displaying the screen even in the shift mode by the user's key input.

(Example 4)

FIG. 6 is a block diagram of a variable speed playback apparatus of a DVCR when an MPEG digital video signal is input according to a fourth embodiment of the present invention, and descriptions of the same components as those in the second or third embodiment will be omitted. Let's do it.

However, the fourth embodiment is an I-frame which reduces the data amount of the I-frame detected by the I-frame processing unit 33 between the I-frame processing unit 33 and the switching unit 34 in the third embodiment. A data reduction unit 44;

The second storage unit 45 temporarily stores the reduced I frame data.

In addition, a difference is configured in that it includes a reproducing output amplifier 51 for amplifying a signal reproduced by the reproducing section 50 using a linear head and applying it to the deformatting section 52.

Referring to the operation, the I frame detector 43 detects I frame data existing in the first MPEG digital video signal.

The detected data amount is reduced by the I-frame data reduction unit 44 and temporarily stored in the second storage unit 45, and then stored at the same position on the helical track using the helical head according to the output timing signal of the controller 46. To record.

The image quality is slightly lowered due to the reduction of the I-frame data amount, but the shift reproduction has nothing to do with the image quality since it is mainly for search purposes.

When the recorded I frame data is reproduced, it is reproduced using a linear head, and the reproduced signal is amplified by the reproduction output amplifier 51 and decoded by the deformatting unit 52 so that the amplified signal can be displayed on a TV screen. Formatting

At this time, reducing the detected I frame by the I frame reduction unit 44 is to record more I frame data so as to have a natural playback picture.

Further, amplifying the reproduced output signal using the linear head is to prevent the reproduction output level from being lowered when the user enters the double speed mode.

Therefore, in the fourth embodiment, it is possible to record more I frame data, and to configure the reproduction output amplifier 51 capable of amplifying the reproduction output signal, thereby further improving the reproduction reproduction output displayed on the TV screen. It would be.

(Example 5)

FIG. 7 is a block diagram of a variable speed playback apparatus for DVCR when an MPEG digital video signal is input according to a fifth embodiment of the present invention, and descriptions of the same components that overlap with the second, third, and fourth embodiments will be omitted. Shall be.

Looking at the configuration, the system decoder and I frame start code detection unit 61 for detecting the start position of the I frame and issuing packetization information by performing semi-decoding for the transmission packet of the input MPEG digital video signal;

A VLD 62 for stretching the compressed I frame at which the start position is detected;

A storage unit 64 which temporarily stores all or part of the extracted I frames and outputs them according to an output timing signal;

A packetization and sync block format unit 65 for encoding the output shift data into a format recognizable by an MPEG decoder and converting the shifted data into a sync block format to which information such as sync, ID, parity, etc. is added so as to be recorded on a tape; It is composed.

First, an input compressed MPEG digital video signal is decoded and a start position of an I frame serving as a reference video of all images is detected.

Then, the compressed I-frame data from which the start position is detected is expanded in the VLD 62.

All or part of the stretched I-frame data is extracted as the shift data by the shift data extracting unit 63 and temporarily stored in the storage unit 64.

In this case, a part of the I frame data is extracted in order to implement a natural shift screen by recording more shift data as in the feature of the present invention.

The I-frame data stored in the storage unit 64 is applied to the packetization and sync block format means 65 according to one control signal and encoded in a format recognizable by the MPEG decoder.

Then, it converts to sync block format to which sync, ID, and parity are added, and records the same in the helical track of the video tape by the helical head.

The recorded shift data is reproduced using a linear head.

As described above, the variable speed reproduction apparatus of the DVCR according to the present invention has the following effects.

First, since the shift data is recorded only at the same position of each helical track when the shift data is recorded, there is no recording position error, and there is no advantage of using a complex multiplexing device.

Second, since the data is detected using the linear head during the shift reproduction, the shift data detection is accurate and precise tracking is required, so the system for shift reproduction is simplified.

Third, since different shift data are recorded regardless of each speed mode, there is an advantage that the waste of tape is reduced compared to the method of repeatedly recording the same shift data according to the conventional shift mode.

Fourth, since the amount of shift data is reduced and recorded, more shift screens can be recorded, thereby achieving a natural shift playback screen.

Claims (5)

A DVCR capable of recording digital broadcast signals and shifting reproduction, comprising: digital data processing means for separating an input digital video signal into normal reproduction data and shift reproduction data; Recording means for recording the shift reproduction data to the nth track by the helical head on the same position; Reproducing means for reproducing the shift data recorded at the same position of the helical track using a linear head; And a control means for controlling the recording position of the shift data. 2. The apparatus of claim 1, further comprising: a system decoder and shift data start code detection means for detecting a start position of shift data by performing semi-decoding of a transmission packet of an input digital video signal; A VLD for extending the compressed shift data output from said system decoder and shift data start code detecting means; Shift data extracting means for extracting all or part of the extended shift data; Second storage means for temporarily storing the extracted shift data; Packetization which encodes the shift data stored in the second storage means into a recognizable format by the packetization information provided by the system decoder and the shift data start code detecting means, and converts the shift data into a sink block format to which sink, ID, and parity are added; And a sync block formatting means. A normal playback data processing means for extracting normal speed playback data from the input digital video signal and converting it into a sync block format; First storage means for temporarily storing the sync block format; And a multiplexing means for selectively outputting the normal reproduction data format and the shift reproduction data stored in said first storage means according to one selection control signal of said control means. The system of claim 1, wherein the control means comprises: a system controller for controlling the entire system; And a shift timing control unit generating a traveling speed signal of the tape to control the shift of the tape. The shift data is a DVCR shift playback apparatus characterized by extracting only I-frame data from MPEG data.