JPH03113886A - Picture recording and reproducing device - Google Patents

Abstract

PURPOSE:To retrieve a boundary position between a recorded picture area and unrecorded picture are at a high speed and at a low cost by transporting a tape at a high speed, detecting S-IDs recorded at prescribed intervals at the time of recording a picture data and detecting the time when the above detecting interval becomes longer than a prescribed time. CONSTITUTION:A recording signal outputted from a signal recording/reproducing part 24 becomes a PCM main data, and S-ID flags are generated from a header discriminating signal (S-ID) generating part 26 for a given period of time from the lead of a page, and is supplied together with the PCM main data to a head 40, so that the S-IDs for a given number of tracks are added to the lead of each page. Then, at the time of fast forwarding the recording medium (tape) 39, the S-IDs are reproduced and detected by the head 40, the signal recording/ reproducing part 24 and an S-ID detecting part 27, and the boundary position between the recorded area and the unrecorded area is decided upon the time when a time interval for detecting the S-ID becomes more than the prescribed value. By this method, the boundary position between the recorded picture area and the unrecorded picture area can be retrieved at low cost and high speed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to an image recording and reproducing apparatus that digitizes image information and records and reproduces it on a recording medium (magnetic tape).

(Prior Art) Conventionally, in this type of image recording and reproducing apparatus, data is recorded on a magnetic tape (hereinafter simply referred to as tape) when recording new additions.
By recording recording end mark data in the PCM area of a certain number of tracks from the last recorded position,
The end position, which is the last recorded area of the tape, was identified. Alternatively, absolute addresses that simply increase from the beginning of the tape are written in a subcode area, etc., and the absolute address corresponding to the recording end position is written as a TOC (Table
Of Contents),
At the time of additional recording, the absolute address of the recording end position is known from this TOC data, and the recording end position is identified by an absolute address search.

However, the former method has the disadvantage that it takes time to detect the end position because the only way to accurately detect the recording end mark signal is to perform normal playback. In addition, the latter method uses a TOC and the like, which makes the control of the device complicated and requires a buffer memory, a memory control circuit, etc., resulting in an excessive cost.

(Problems to be Solved by the Invention) As described above, in the method of recording a recording end mark to identify the boundary position between a recorded image area and an unrecorded image area on a tape, it takes time to detect the end position. There was a drawback that it took a long time. Another disadvantage is that the method of writing an absolute address corresponding to the recording end position at a fixed position on the tape in order to identify the boundary position between the recorded image area and the unrecorded image area on the tape is too costly. was there.

SUMMARY OF THE INVENTION The present invention aims to eliminate the above-mentioned drawbacks, and is an image recording and reproducing device that can search for the boundary position between a recorded image area and an unrecorded image area at high speed without putting a burden on the magnetic tape running system, etc., and at low cost. is intended to provide.

[Structure of the invention]

(Means for Solving the Problems) The present invention provides an image recording and reproducing apparatus for recording and reproducing image signals on a recording medium, including an identification signal generating means for generating an identification signal indicating a division of a predetermined screen, and an identification signal generating means for generating an identification signal indicating a division of a predetermined screen. recording means for recording the identification signal generated by the above at a predetermined interval on a recording medium; and identification signal reproduction detection means for reproducing and detecting the identification signal on the recording medium when the recording medium is fast-forwarded. a timer for timing the time interval at which the identification signal is detected by the identification signal reproduction detection means; and a timer for measuring the time interval at which the identification signal is detected by the identification signal reproduction detection means, and a time point recorded on the recording medium when the time interval measured by the timer reaches a predetermined value or more. It has a configuration comprising a position determining means for determining a boundary position between an area and an unrecorded area, and a tape running stop means for stopping the running of the tape when the position determining means detects the boundary position of the area.

(Function) In the image recording and reproducing apparatus of the present invention, the identification signal generating means generates an identification signal indicating the division of N screen bones. The recording means records the identification signal generated by the identification signal generating means at a predetermined position on the recording medium at regular intervals. The identification signal reproduction detection means reproduces and detects the identification signal on the recording medium when the recording medium is fast-forwarded. The timer measures the time interval at which the identification signal is detected by the identification signal reproduction detection means. Position determination means determines the point in time when the time interval measured by the timer exceeds a predetermined value as the boundary position between the recorded area and the unrecorded area on the recording medium. The tape running stop means stops the tape running when the boundary position of the area is detected by the position determining means.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of the image recording and reproducing apparatus of the present invention. 1 is an input terminal that inputs an analog video signal, 2 is an A/D converter that converts the analog video signal to a digital video signal, and 3 is an input terminal that separates the video signal into a luminance signal and a color signal and processes each signal. , a Y/C separation processing unit that synthesizes and outputs the signal again in a predetermined format, 4 a bus buffer that sends the signal onto the bus controller, 5 a bus that transmits the signal, and 6 a D/A converter that converts the signal on the bus 5. 6 a path buffer, 7 a D/A converter that converts the digital video signal into an analog video signal, 8 a modulation unit that modulates the analog video signal, 9 an output terminal that outputs the analog video signal, 11 12 is a frame memory into which data for one screen is written; 13 is a bus buffer that sends the data on the bus 5 to the bus 15; 14 is a bus buffer that sends the data on the bus 15 to the bus 15. 15 is a bus for transmitting signals, 1 is a path buffer for sending signals to
6 is a buffer memory that temporarily stores video signals to maintain the continuity of video signal 6; 18 is a memory address generator that generates addresses for the buffer memory 16; and 19 is a header generator that generates ladder data for pages. , 21 is a timing control section that controls the operation timing of each section; 22 is a microcomputer section that controls recording/reproduction of video signals and cueing of areas where signals are not recorded;
23 is a header detection unit that detects a header recorded on the tape 39; 24 is a signal recording/reproducing unit that records/reproduces a video signal on the tape 39; and 25 is an error detection and correction unit that corrects errors in the recorded/played signal. , 26 is a 5-ID that generates a header identification signal (hereinafter referred to as 5-ID) flag.
The generation unit 27 detects the 5-ID on the tape 39.
ID detection unit, 28 is a timer that measures the detection interval of 5-ID, 30 is a reel motor 31, 34, drum motor 32
and a servo control unit that controls the rotation of the capstan motor 33; 31 is a reel motor that rotates the supply reel 35; 32 is a drum motor that rotates the drum 36; 33 is a capstan motor that rotates the capstan 37; 34 is a tick A reel motor that rotates the up reel 38, 35 is a supply reel, and 36 is a head 4.
0 is mounted on a rotating drum, 37 is a capstan that runs the tape 39 at a constant speed, 38 is a pick-up reel,
39 is a tape on which signals are recorded/reproduced, 40 is tape 3
9 is a head for recording/reproducing signals; 41 is a rotation speed detector for detecting the rotation speed of the drum 36; and 42 is a rotation speed detector for detecting the rotation speed of the pickup reel 38.

Here, 5-ID generating section 26 is an identification signal generating means, microcomputer section 22, signal recording/reproducing section 24, head 40 is a recording means, head 40, signal recording/reproducing section 24.5-ID detecting section 27 is an identification signal reproduction detection means;
The timer 28 has a timing means and a microcomputer section 22.
constitutes a position determination means, and the microcomputer section 22 and servo control section 30 constitute a tape running stop means.

Next, the operation of this embodiment will be explained. For example, an NTSC analog video signal is supplied to the recording input terminal 1 and introduced into the A/D converter 2 . Here, the digitized image information is separated into brightness information and color information in a brightness signal/color signal separation section 3, subjected to prescribed signal processing, and then synthesized again in a prescribed format. and stored in the frame memory 12. At this time, the address generated from the frame memory address generation section 11 specifies the write address or read address of the data in the frame memory 12. The data for one screen written in the frame memory 12 is supplied to the modulation section 8 via the bus 5, the bus buffer 6, and the D/A converter 7, where it is converted into the original video signal and sent to the output terminal 9 for monitoring. derived.

At the same time, one screen worth of data written in the frame memory 12 is transferred to the buffer memory 16 via the bus controller, the path buffer 13, and the bus 15. Next, the memory address generator 18 supplies the read address to the buffer memory 16 to read the image data in the buffer memory 16, and the read image data is supplied to the signal recording/reproducing unit 24 via the bus 15. be done. At this time, in response to a page header instruction from the microcomputer section 22, ladder data for the page generated by the header generation section 19 is supplied to the signal recording/reproducing section 24. The signal recording/reproducing section 24 processes the input signal to produce a recording signal. Signal recording/
The recording signal output from the reproducing section 24 is further added with an error detection and correction code by the error detection and correction section 25, and converted into PCM.
This becomes the main data. Also, a 5-ID flag is generated from the 5-ID generation unit 26 for a certain period of time (for example, 9 seconds) from the beginning of the page, and this becomes subcode data and is sent to the PCM.
It is supplied to the head 4o together with the main data. As a result, recording in the format shown in FIG. 2 is obtained on the tape 39.

Here, FIG. 2 is a diagram showing an example of the recording format recorded on a tape by the helical scan method using the above-mentioned device. While establishing
5-IDs corresponding to a certain number of tracks are added to the beginning of each page. However, FIG. 2 (A> is a partially enlarged view of FIG. 2 (B>).

Next, the reproduction system of the above system will be explained.

During normal reproduction, the signal reproduced by the rotary head 40 is supplied to the signal recording/reproducing section 24. Here, the PCM main data is subjected to error detection and correction by the error detection and correction section 25. Further, the subcode data reproduced by the head 40 is sent to the 5-ID detection section 27, 5-ID is detected, and a detection signal is sent to the microcomputer section 22.

The PCM main data processed by the signal recording/reproducing section 24 is transferred and written in the memory 16 for one screen from the first image data whose header was detected by the header detecting section 23. Next, this screen data is serialized and read out from the buffer memory 16, and transferred to the frame memory 12 via the bus 15 and bus buffer 14.

After the data in the frame memory 12 is read out by the frame memory address generation section 11, it is converted into an analog video signal via the bus 5, the D/A converter 7, and the modulation section 8, and is output to the output terminal 9. .

Next, the recording end position search operation of the above system will be explained. First, the servo control section 30 controls the reel motor 31 to rotate the sub reel 35 in the winding direction, and as shown in FIG.
Performs a 5-ID search using 0. Here, Fig. 2 (C)
``A'' shown in Figure 2 indicates the starting position when the tape is installed in the device. At this time, the reproduced signal reproduced by the head 40 is sent to the bus 15 via the signal recording/reproducing section 24. Thereafter, the 5-ID detection unit 27 sends S-I Dt! on the bus 15. - When detected for the first time, this is notified to the microcomputer section 22. The microcomputer section 22 sets (including resetting) the counter of the timer 28 at the time of detection of this 5-ID. Next, the microcomputer 22 controls the servo control section 30.
A command is issued to rotate the pick-up reel 38 in the fast forward direction to perform a 5-ID search. In this search, the signal 5-ID signal detected by the rotary head 40 is 5-
It is supplied to the ID detection section 27.

Here, when the subcode data is detected by the 5-ID detection section 27, the detection signal is sent to the microcomputer section 22, and according to the instructions from the microcomputer section 22, the timer 2
8 is reset. When the timer 28 counts over before being reset, the signal is sent to the microcomputer section 22.

Upon receiving the signal, the microcomputer section 22 detects the position of the end of the recorded area of the tape, issues an instruction to the servo control section 30, controls the tape running system, and stops the tape at the recording end position. . However, at this time, the timer set value of the timer 28 is set to t, which is the sum of the time T determined from the search speed and the one-page interval (constant) and the additional recording margin α. The "mouth" shown in Figure 2 (C),
"C" means that 5-ID was detected within t, so timer 2
The counter 8 is reset without counting over, but when it reaches the boundary of the unrecorded portion of "E", the timer 28 counts over as shown in FIG. 2(D), as described above. At this point, the tape is stopped, and after returning at the specified speed for β (a time equal to or smaller than the time γ for passing the number of tracks passed at the search speed in time α at a specified speed, for example, minus 3 times the speed), the tape is returned at the specified speed. ) will stop at the point indicated by "to".

According to this embodiment, the tape is played back by running at high speed,
By detecting 5-ID recorded at predetermined intervals during image data recording and detecting the point in time when this detection interval becomes a predetermined time or more, the end of the recorded area of the tape is detected, so the tape is recorded at high speed. Even when running, it is possible to reliably detect the end of the recorded area, that is, the beginning of the unrecorded area, and high-speed search can be realized at low cost.

〔Effect of the invention〕

As described above, according to the image recording and reproducing apparatus of the present invention,
The boundary position between the recorded image area and the unrecorded image area (the beginning of the unrecorded image area) can be searched at high speed at low cost.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the image recording and reproducing apparatus of the present invention, and FIG. 2 shows an example of the recorded image format for one page formed on a tape by the apparatus shown in FIG. 1st
FIG. 3 is a diagram illustrating an operation of searching for a recording end position of the apparatus shown in the figure. 2... A/D converter 3... Luminance signal color signal separation circuit 7... D/A converter 8... Modulator 11...
Frame memory address generation section 12... Frame memory 16... Buffer memory 18... Memory address generation section 19... Header generation section 21... Timing control section 22... Microcomputer section 23...・Header detection section 24...Signal recording/reproduction section 26...5-ID generation section 21...5-ID detection section 28...Timer 30...Servo control section 36...Drum 40. ··head

Claims (1)

[Scope of Claims] An image recording and reproducing apparatus for recording and reproducing image signals on a recording medium, comprising: an identification signal generating means for generating an identification signal indicating a division of a predetermined screen; and an identification signal generated by the identification signal generating means. recording means for recording the information at predetermined positions on a recording medium at regular intervals; identification signal reproduction detection means for reproducing and detecting an identification signal on the recording medium when the recording medium is fast-forwarded; and identification signal reproduction; a timer for measuring the time interval at which the identification signal is detected by the detection means; and a timer for measuring the time interval at which the identification signal is detected by the detector; An image recording and reproducing apparatus comprising: a position determining means for determining a boundary position; and a tape running stop means for stopping the running of the tape when the position determining means detects a boundary position of the area.