JPH0325759A - Recording system discriminating method in reproducing device - Google Patents

Abstract

PURPOSE:To quickly perform a reproduction processing by performing a pre-search processing which detects the attribute of a frequency modulated video signal and stores a detected result in a memory at every track, and discriminating one out of plural kinds of recording systems. CONSTITUTION:When a video floppy disk is loaded, a bucket open/close detecting switch 41 and a VF detecting switch 42 detect it, and a system controller 27 performs the pre-search processing. The processing is to check the attribute of the frequency modulated video signal and to store the result in the memory 26. Simultaneously, it is discriminated whether a system is a high-band recording system or a normal-band recording system, and it is stored in the memory 26. A switching signal is supplied to a switching circuit 24 corresponding to the discriminated result of a recording system at every track stored in the memory 26. A reproduced Y signal passing an LPF 21 is supplied to a synchronizing separator circuit 25 by energizing the terminal (a) of the circuit 24 in normal-band recording, and a reproduced signal passing an LPF 22 to the synchronizing separator circuit 24 by energizing the terminal (b) of the circuit 24 in high-band recording. In such a way, the reproduction processing can be quickly performed.

Description

[Detailed Description of the Invention] Summary of the Invention When a recording medium is loaded, it is determined whether a video signal is recorded on each track of the recording medium, and whether the recorded video signal is by field recording or by frame recording. The recording method of the recorded video signal (for example, high band recording,
normal band recording), and the results of this determination are stored in memory for each track. This makes it possible to quickly reproduce the video signal by omitting the process of determining the recording method during the reproduction process.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for determining a recording format in an apparatus for reading and reproducing an FM modulated video signal recorded on a recording medium, such as a method for determining a recording format in a still video signal reproducing apparatus.
The present invention relates to a method for determining a normal band recording method.

Conventional technology and its problems When recording still video signals on a high-density magnetic floppy disk using an electronic still camera (still video camera) or other recording device, there are two recording methods: normal band recording method and high band recording method. There is a method.

A still video signal consists of a luminance signal (Y signal) and a color signal (C signal) (generally color difference signals R-Y and B-Y). In the normal band recording method, a carrier wave with a center frequency of 7 MHz is FM-modulated by a luminance signal Y (this FM modulated wave is abbreviated as a Y-RF signal). Color difference signal RY, B
−Y with frequencies of 1.2 MHz and 1, respectively.
．． The 3 MHz carrier wave is FM modulated (these FM modulated waves are abbreviated as C-RF signals), and these Y-RF,
C-RF signals are mixed and recorded on a video floppy track. The frequency allocation of these Y-RF signals and C-RF signals is shown in FIG. i2(A). The Y-RF signal's sync tip frequency is 6 MHz, white peak frequency is 7.5 MHz, and frequency deviation is 1.5 MHz.
It is Hz.

In a high-band recording method for recording a high-resolution still video signal, the center frequency of a carrier wave for FM modulation of the luminance signal Y is set to 9 MHz. As shown in Figure t2 (B), the sync chip frequency of the Y-RF signal is 7.7MHz, and the white peak frequency is 9.7M.
Hz, and the frequency deviation is 2 MHz.

The C-RF signal is the same as the normal band case.

As described above, when the recording method of still video signals differs, the reproduction/reproduction method also differs. Therefore, in a device that can reproduce both normal band and high band.
A normal band dedicated circuit section and a high band dedicated circuit section are provided. It is not specified which method is used to record stills and video signals on the video floppy installed in the playback device or on each track of the video floppy (especially video signals recorded using the normal band recording method and video signals recorded using the normal band recording method). (If video signals recorded using a high-band recording method are mixed), the playback device determines the recording method from the video signal read from the video floppy, and switches the dedicated circuit section based on the result of this determination. It is necessary to do this. This is why it is necessary to automatically determine the recording method of the RF video signal.

Summary of the Invention Purpose of the Invention This invention provides F
It is an object of the present invention to provide a method for determining a recording method in a reproducing device, which performs processing for determining a recording method for an M-modulated video signal by using a time period of presearch processing performed when a recording medium is loaded.

Structure and Effects of the Invention A method for determining a recording method according to the present invention detects that a recording medium is loaded at a reproduction position in an apparatus for reproducing an FM modulated video signal recorded on a recording medium having a plurality of tracks. In response to this detection, a presearch process is performed to detect the attributes of the FM modulated video signal recorded on all tracks of the recording medium and store the detection results in memory for each track. During processing, it is determined which of the multiple recording methods in which the FM modulated video signal read from each track was recorded using FM modulation using carrier waves of multiple different frequencies, and the determination result is determined. is characterized in that it is stored in memory for each track.

The attributes of the FM modulated video signal refer to field/frame recording data indicating whether a video signal is recorded on each track and whether the video signal is field recorded or frame recorded. This pre-search process for determining the attributes of a video signal and storing it in memory requires at least IV (V is the vertical scanning period), usually about 3V, for each track. During this time, it is fully possible to perform recording method discrimination processing such as high band/normal band discrimination.

According to this invention, the recording format of each track is determined using the time period of the presearch process and stored in the memory, so the recording format determination process can be omitted when playing each track, and the recording format Reproduction processing including switching of dedicated circuit parts can be quickly performed.

Hereinafter, an embodiment in which the present invention is applied to the above-mentioned discrimination between normal band recording and high band recording of still video signals will be described in detail. However, this invention is applicable not only to still video signals.
Needless to say, the present invention can also be applied to determining the recording format of a movie video signal recorded on a video tape, and to determining the recording format of other video signals.

DESCRIPTION OF THE EMBODIMENTS FIG. 1 is a block diagram showing a part of an apparatus for reproducing still video signals recorded on a video floppy.

The still video signal reproducing device is equipped with a packet (not shown) for loading a video floppy as a recording medium. The opening and closing of this packet is detected by the detection switch 41. A switch 42 is also provided to detect the presence of a video floppy in the bucket. These detection switches 41. 42 detection signals are detected by the system.
is given to the controller 27.

When the packet open/close detection switch 4l detects that the packet of the playback device has been opened and then closed, and the video floppy detection switch 42 detects that a video floppy is loaded in the packet, a new video floppy is inserted. ◆The floppy may have been loaded or the video floppy may have been replaced, so the system controller 27 performs presearch processing. Presearch processing is the process of checking the attributes of the FM modulated video signal recorded on each track of the video floppy (presence of recording, detection of field/frame data, etc.) and storing the results in the memory 2B for each track. The purpose of this is to use the time period of this presearch process to determine whether the FM modulated video signal recorded on each track is of the high band recording method or the normal band recording method. High band/normal band discrimination processing is performed,
The determination results are also stored in the memory 26 for each track.

Now. A still image signal (hereinafter referred to as an RF signal) which is FM modulated and recorded on a track of a video floppy loaded in a playback device is read by a magnetic head 10.
A preamplifier 11 is provided. The reproduced RF signal amplified by the amplifier l1 is supplied to the equalizer 12, where it is compensated so that the upper and lower sideband components are approximately equal.

The reproduced RF signal that has passed through the equalizer 12 is sent to the field/frame conversion circuit l5 on the one hand, and to the DPS on the other hand.
They are respectively applied to the low-pass filter 13 for the K signal.

The field/frame conversion circuit i5 includes a delay circuit 16 that delays the still video signal by 0.5H, and a video signal (hereinafter referred to as a through video signal) and a video signal delayed by 0.5H (hereinafter referred to as a 0.5H delayed video signal). It includes a changeover switch l7 for selecting either one. The changeover switch l7 is controlled by a changeover control signal given from the timing generation circuit 28.

This changeover switch i7 is configured so that during playback of field recording, the changeover switch 17 is connected to the a terminal side during the first field scanning period of interlace scanning, and a 0.5H delayed video signal is output from the circuit l5. next second
During the field scanning period, the switch 17 is connected to the b terminal side, and switching control is performed so that the through video signal is output. Further, for the video signal of frame recording, the changeover switch 17 remains connected to the b terminal side. A timing generation circuit 28 that generates a switching control signal for performing such switching control is supplied with field/frame data determined by the demodulation result of the DPSK signal, which will be described later, from the system controller 27.

On the one hand, the output signal of the field/frame conversion circuit 15 is passed through the Takagi pass filter 1 for luminance signals, which has a cutoff frequency that allows only the FM modulated luminance signal Y-RF component to pass.
9, the Y-RF signal is extracted,
On the other hand, only the C-RF signal is extracted by applying it to a color signal low-pass filter {8 having a cutoff frequency that allows only the FM modulated color signal C-RF signal to pass. This C-RF signal is subjected to demodulation processing by a demodulation circuit (not shown).

The Y-RF signal that has passed through the Takagi pass filter l8 is given to the FM demodulation circuit 20. The luminance signal Y obtained by being demodulated by the demodulation circuit 20 is passed through the first low-pass filter 21 . The signal is applied to a second low-pass filter 22 and a high band/normal band discrimination circuit 30, which will be described later.

Both the first low-pass filter 2i and the second low-pass filter 22 are for removing carrier wave components of FM modulation. The first low-pass filter 21 is for the normal band recording method, and its cutoff frequency is approximately 4.5 MHz, which corresponds to the frequency bandwidth of the baseband signal for normal band recording. The filter 22 is for the high band recording method, and its cutoff frequency is set to approximately 6 MHz, which corresponds to the frequency 11} bandwidth of the baseband signal for high band recording.

The normal band reproduction signal from which the carrier component has been removed by passing through the first low-pass filter 2l is applied to the a terminal of the switching circuit 24. Second low pass filter 2
The high band reproduction signal from which the carrier component has been removed by passing through the attenuator 23 is supplied to the attenuator 23.

The FM demodulation circuit generates an output voltage that is approximately linear with respect to the frequency of the human input signal. Therefore, the amplitude of a high band reproduction signal with a wide frequency deviation is generally larger than that of a normal band. Attenuator 23 is R
This is to correct this amplitude difference in the reproduced signal that occurs during the demodulation process of the F signal. The amplitude of the high band reproduction signal is attenuated to be approximately equal to the amplitude of the normal band reproduction signal. As a result, the amplitude of the high band reproduction signal applied to the b terminal of the switching circuit 24 becomes approximately the same as the amplitude of the normal band reproduction signal applied to the a terminal.

The high band/normal band discrimination circuit 30 discriminates the recording method of the RF signal in the above-mentioned presearch process. A high band/normal band discrimination signal representing the recording method is applied to the memory 26 included in the system controller 27. Details of the high band/normal band discrimination circuit 30 will be described later.

During playback and presearch processing. The switching circuit 24 is supplied with a switching control signal according to the determination result of the recording method (high band/normal band) for each track stored in the memory 2G, as will be described later. When this switching control signal indicates normal band recording, the a terminal side of the switching circuit 24 is rendered conductive. The normal band reproduced Y signal that has passed through the l-th low-pass filter 21 is output and also provided to the sync separation circuit 25 . When the switching control signal indicates high band recording, the b terminal side of the switching circuit 24 becomes conductive, and the high band reproduction signal that has passed through the second low-pass filter 22 is output as the luminance signal Y. The signal is applied to the synchronization separation circuit 25. A synchronization signal is extracted from the luminance signal Y by the synchronization separation circuit 25, and is applied to the high band/normal band discrimination circuit 30 for use in discrimination processing.

The DPSK signal is mixed with an FM modulated video signal and recorded on a video floppy.
Only the data signal component recorded using the phase-shut key method (differential phase shift keying) is allowed to pass through. Data recorded in the DPSK system includes, for example, field/frame data indicating whether the FM modulated video signal is based on field recording or frame recording. The signal that has passed through the DPSK signal low-pass a filter l3 is applied to a DPSK demodulation circuit 14, where its data is demodulated. The demodulated data is given to the memory 26 of the system controller 27, and a track map is created for storing data for each track. An example of this track map is shown in FIG.

In this figure, the number O. written on the vertical axis. to, 20.
30. 40 represents the lO digit of the truck Na, and the numbers 0 to {0 are the 1 digit (1
(0 is the only exception), and the combination of these numbers represents the track size of the video floppy from Na1 to Na50. The code "1" or "0" shown in the area where the numbers on the vertical axis intersect with the numbers on the horizontal axis represents the track field/frame data and high band/normal band discrimination data of that track Na. . That is, the upper row of each section shows the field/frame ψ data detected by D'P S K demodulation.
Tracks marked with "1" indicate frames recording tracks, and tracks marked "0" indicate tracks of field recording. The bottom row of each section is from 7 to Iband/
High band/normal band discrimination data discriminated by the normal band discriminating circuit 30 is shown. Tracks marked with "1" are tracks of high band recording, and tracks marked with "0" are tracks of normal band recording. It is.

During reproduction, among the data stored in the memory 2G, field/frame data corresponding to the track being reproduced is supplied to the timing generation circuit 28, and high band/normal band discrimination data is supplied to the switching circuit 24.

FIG. 3 is a flowchart showing, in particular, the initial operation procedure among the processing procedures of the still/video image signal reproducing apparatus.

When the packet open/close detection switch 4l detects that the packet has been opened and then closed, and the video floppy detection switch 42 detects that a video floppy is inserted (YES in step 5i). ), presearch processing is started (step 52). The presearch process is performed for each track from the positive 1 track to the NCL50 track. The video signal (on which the DPSK signal is superimposed) read from the rotating video floppy track is applied to the DPSK131 circuit t4 and the high band/normal band discrimination circuit 30 as described above. Based on the demodulated data of the DPSK demodulation circuit I4, field/frame data is created during at least IV (the time of one revolution of the biteo floppy) or about 3V. Also. During this time, no band/normal band discrimination data is obtained within a time of IV.

These field/frame data and /% band/normal band discrimination data are stored in the memory 2G for each track, and the track map shown in FIG. 2 is created (step 53).

In the subsequent playback process, the field, /frame, and data of the track to be played back and the high hand/
As described above, the normal band discrimination data is read from the track map and the switching circuits 17 and 24 are controlled to switch.

In the presearch process, instead of or in addition to the DPSK data extraction process, a process of determining whether a video signal is recorded on each track of the video floppy is sometimes performed. This process is called a track search process, and the presence or absence of recording is determined based on whether the level of the envelope of the signal output from the IA head 10 is above a predetermined level.

Next, the high band/normal band discrimination processing by the low band/normal band discrimination circuit 30 will be described.

A detailed block diagram of the high band/normal band discrimination circuit 30 is shown in FIG.

Referring to FIG.
2 are given respectively.

FIG. 6 shows the characteristics of the FM demodulation circuit 20. FM
The demodulation circuit has a portion where the output voltage changes linearly with respect to the frequency of the human input signal, and this portion is used for FM demodulation. As mentioned above, the sync chip frequency of the normal band recording method is 6 MHz, and the white peak frequency is 7.5 MHz. It is assumed that the output voltage levels of the return and fall circuits 20 for these frequencies are gN3'gN1, respectively. Further, the demodulated output corresponding to the pedestal (black) level frequency of the normal band is assumed to be gN2. Similarly, the sync chip frequency (7.7 MHz), pedestal level frequency and white peak frequency (9.7 MHz) of the high band recording method
) is the output level of demodulation circuit l5 corresponding to g
, g , g .

03 H2 Il1 On the other hand. As shown in Figure 7, the frequency difference between the white peak and the sync tip is a, the frequency difference between the white peak and the vedestal level is b, and the frequency difference between the pedestal level and the sync tip is C. NT
According to the SC format, these frequency differences a, b,
Regardless of the type of recording method, the ratio of c is a:b:c=
1: Q. 714: It is fixed as 0.28B.

As mentioned above, the normal band frequency deviation (represented by aN) is 1.5 MHz, and the high band frequency deviation (represented by aH) is 2.0 MHz.
Since it is MHz, it is "N/aH" - 3/4. Assuming that the characteristics of the demodulation circuit 20 are linear. (g −
g ) / (gH1-.gH3) -NIN
It becomes 3 3/4.

Pedestal level and sync in normal band◆
The frequency difference with the chip is C. Let CI1 be the frequency difference between the vedestal ● level and the sync tip in the high band N. As explained with reference to Figure 7, since c/a is constant regardless of the recording method,
c/a -C11/all-NN c/a. a N / a H - 3/
4, so it becomes C N /C H-3/4. Expressing this relationship in terms of the output voltage difference of the demodulation circuit l5,
C N / C +1 - (g - g ) / (
g,,2-g,,3) - 3/4 and N2
~3.

In this high band/normal band discrimination circuit 30, (g
-g) or (g112-g[3) is detected. Also, (g −g ) and (g112− gH
3), the reference level VR between N2 and N3 is set in advance.

Then, the detected (g − g ) or (g112
By comparing N2 N3 g) with the reference level vR, it is possible to determine whether the 113 recording method is normal band. It is determined whether it is a high band.

FIG. 5 shows the relationship between the synchronizing signal portion of the demodulated luminance signal Y and sample pulses SPI and SP2 for sampling the pedestal level and sync tip level from this same signal portion.

In Figure 4. Based on the synchronization signal provided from the synchronization separation circuit 25, the timing generation circuit 35 generates the above-mentioned sample pulses SPI and SP2, and the sample and hold circuits 31. 32 each. Sample and hold circuit 31. 32, each demodulated luminance signal Y is input manually as described above. The sample hold circuit 32 detects and holds the pedestal level (g or gH) at the timing of the sample pulse SPI. Sump N2 The loop hold circuit 32 syncs at the timing of sample ●pulse SP2 ◆chip ◆level (gN3 or g11
3) Detect and hold.

The pedestal signal detected by the sample and hold circuit 3l
A signal representing the level is sent to the differential amplifier 33 via the resistor R1.
A signal representing the sync tip level detected by the sample and hold circuit 32 is applied to the negative input terminal of the differential amplifier 33 via a resistor R2. The differential amplifier 33 has a feed loop in which the output signal is fed back to the positive input terminal via the resistor R4. Moreover, the negative input terminal is grounded via a resistor R3. This differential amplifier 33 creates a level difference (g) between the pedestal level and the sink C chip◆ level.
-g) or (gH2gH3) is detected.

The output of the differential amplifier 33 is applied to the positive input terminal f of the comparator 34. The reference level VR is applied to the negative input terminal of the comparator 34. Therefore, in the normal band, since (gN2 ``N3) < VR, the comparator 34 outputs an L level signal. In the high band, the comparator 34 outputs an H level signal from H2 1+3, which is (g g)>VH. The output signals of the comparator 34 serve as high band/normal and red band discrimination signals.

As described above, a track map representing the recording method of each track of the video floppy is created based on this high band/normal band discrimination signal.

Sample and hold circuit 31. The sampling operation in step 32 (generation of sample pulses SPI and SP2) is performed in the mixed synchronization signal portion, but may be performed only once or multiple times. Further, it may be performed every time a period of 1V has elapsed, or it may be performed only once during reproduction of one track.

Figure 9 shows a modification of the playback device shown in Figure 1.
The portions that are different from those in FIG. 1 are extracted and shown.

The luminance signal Y demodulated by the FM demodulation circuit 20 is given to a low-pass filter 2LA and a high band/normal band discrimination circuit 30. The low-pass filter 21A is for removing the carrier wave component of FM modulation similarly to the first low-pass filter 21 and the second low-pass filter 22 shown in FIG. 1, and its cutoff frequency is , is set at approximately 6 MHz so that the high frequency components of the high band luminance signal Y can be sufficiently passed through. Demodulated luminance signal Y output from low-pass filter 2LA
is applied to the automatic gain control amplifier circuit 23A.

The automatic gain control amplifier circuit 23A, like the attenuator 23 shown in FIG. 1, is for making the level of the finally output luminance signal Y almost constant regardless of the difference in recording method. The gain of this amplifier circuit 23A is controlled by the output signal of a differential amplifier 33 included in the high band/normal band discrimination circuit 30 shown in FIG. In other words, when the output signal level of the 6-differential amplifier 33 is high (high band), the gain of the amplifier circuit 23A becomes a relatively small value, and conversely, when the output signal level of the differential amplifier 33 is small (normal band), the gain of the amplifier circuit 23A is switched to a relatively large value.

This makes it possible to make the amplitude level of the demodulated video signal constant, which varies depending on the recording method.

The luminance signal Y output from the automatic gain amplification circuit 23A is
One is output and the other is given to the sync separation circuit 25.The 6 sync separation circuit 25 extracts the sync signal from the luminance signal Y and gives it to the timing generation circuit 35 included in the high band/normal band discrimination circuit 30 as described above. That's right.

The reproducing circuit shown in FIG. 8 has a configuration in which only the gain of the amplifier circuit 23A is switched depending on the recording method determination result.
This has the advantage of simplifying the circuit.

FIG. 9 shows another example of the high band/normal band discrimination circuit 30. This high band/normal band discrimination circuit is designated by reference numeral 60. In addition, Fig. 10 shows the main operations of the circuit shown in Fig. 9, especially the operations during the vertical retrace period, and Fig. 11 shows the time axis of the time chart shown in Fig. 10 extended and further expanded. It is shown in detail.

The Y-RF signal input to the high band/normal band discrimination circuit 60 is given to the Schmitt inverter 6l, and is shaped into a pulse signal (or square wave signal) by level discrimination using the zero◆ level threshold. Ru. This pulse signal is input to the counter 62. As will be described later, the counter 62 operates only during the period T2 to count the human pulse signals. The input pulse signal of the counter 62 during this period T2 (normal band sync chip component,
high band sync chip component) and counter 62
The output signal of is shown in FIG.

Figure 10 shows a mixed synchronization signal C of the demodulated video signal.
are extracted and shown. The vertical sync pulse part of this hybrid sync sync signal C is 3H S)'
ne width, and in order to prevent the horizontal synchronization signal from disappearing during that period, this is divided into six pulse parts of 0.07H width every 0.43H. This 0.07H width pulse portion will be referred to as a delimiter pulse portion a.

There are various types of synchronization separation circuits 25, but in this high band/normal band discrimination circuit Go, this circuit 25 detects a vertical synchronization signal delayed by approximately IH from the vertical synchronization pulse part in the mixed synchronization signal C. A device that outputs V is used. This vertical synchronization signal V is the first monostable multivibrator syn
c (MMI)64. The output signal of the monostable multivibrator 64 rises in synchronization with the rise of the vertical synchronizing signal V and is held at the H level for a predetermined time Tt (16 μs in this embodiment). This output signal is applied to the clear terminal of counter 62 and twelve monostable multivibrators (MM2) 135.

The second monostable multivibrator 65 rises in synchronization with the fall of the output of the first monostable multivibrator 64, and then rises for a predetermined time T2 (3.5 μS in this embodiment).
), and this output signal is applied to the enable terminal of the counter 62. Therefore, the counter 62 will operate during this period T2.

The period T2 in which the counter 62 operates is the hybrid synchronization signal C.
Approximately in the middle of the vertical synchronization pulse part S)'ne near, preferably between the second and third delimiting pulse part a. Alternatively, as shown in FIG. This is because although the signal of the sync chip frequency component input to the counter 62 may be disturbed at the edges of the vertical synchronizing pulse portion, this disturbance is thought to be less near the center of the vertical synchronizing pulse portion. Further, this period T2 is set to be located approximately at the center of the adjacent delimiter pulse portions a. This is also to perform the sync chip frequency measurement operation in a portion where signal disturbance is as small as possible.

A hybrid synchronization signal C as shown by the dashed line in FIG. When using a synchronization separation circuit that generates a vertical synchronization signal V that rises with almost no delay from the vertical synchronization pulse part during synchronization, the first monostable multi-by-break 64 has a period almost 1H longer than the period T1. One that outputs a one-shot pulse of time TI2 will be employed.

The counter 62 is cleared by the output signal of the first monostable multivibrator 64, then performs a counting operation while the output of the second monostable multivibrator 65 is at H level, and is output from the Schmitt inverter 6l. In this embodiment, the frequency signal created by the sink chip is divided by 1/16. As described above, the sync chip frequencies are different between normal band recording and high band recording, so even if frequency division is performed at the same ratio, the frequencies after frequency division will be different. In this embodiment, the counting operation period T2 of the counter 62 is set to 3.5 μs. 11th
As shown in the figure, when the input signal is a 6 MHz signal, the output of the counter 15 becomes L level at the end of period T2. In the case of a 7.7 MHz signal, it becomes H level and is held at that level. Therefore, the period T
It is possible to determine whether normal band recording or high band recording is being performed based on the level of the output signal of the counter 62 at the time when 2 has elapsed.

The output signal of the counter 62 is given to a low pass filter 63. The output of the low-pass filter 63 is applied to and stored in the memory 28 included in the system controller as a high band/normal band discrimination signal.

The above processing is performed on all recorded tracks of the video floppy when the 5 presearch processing is performed, resulting in a pre-populated video floppy as shown in Figure 2.
A track map representing the recording method of each track of the floppy is created. Therefore, it is no longer necessary to perform a process of distinguishing between the high band and the normal band each time each track is reproduced.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a diagram showing an example of a track map that is created, and FIG. 3 is a flowchart showing the processing procedure when inserting a video floppy.
It is a chart. Figure 4 is a block diagram showing the high band/normal band discrimination circuit, Figure 5 is a time chart showing the relationship between the synchronization signal of the luminance signal and the sample pulse, and Figure 6 is the FMu
A graph showing the characteristics of the 1-tone circuit, FIG. 7 is a waveform diagram showing the luminance signal. FIG. 8 shows a modification of the circuit shown in FIG. 1, and is a block diagram showing a portion of the playback device. Fig. 9 is a block diagram showing another example of the high band/normal band discrimination circuit, Fig. 10 is a time chart showing the main operations of the circuit shown in Fig. 9, and Fig. 11 is a time chart showing the main operations of the circuit shown in Fig. 10.・The time of the chart is extended to show details. FIGS. 12(A) and 12(B) are diagrams showing frequency allocation, where (A) shows normal band recording and (B) shows high band recording, respectively. io...magnetic head, 17. 24...Switching circuit, 20...Demodulation circuit, 21, 22. 21A...Low pass filter, 2B
...Memory, 27...System Controller, 30. 80...High band/normal band discrimination circuit. That's all Figure 2 3gl Figure 5 Figure 2 (A) Normal Band +8+ NoheX Nokundo 2 3 4 5 6 7 8 Te10 [MH2. )

Claims (1)

[Claims] In an apparatus for reproducing an FM modulated video signal recorded on a recording medium having a plurality of tracks, it is detected that the recording medium is loaded at the reproduction position, and in response to this detection, the recording medium is A presearch process is performed to detect the attributes of the FM modulated video signal recorded on all tracks of the track and store the detection results in the memory for each track. Determining which of a plurality of recording methods in which the modulated video signal is FM modulated using a plurality of carrier waves of different frequencies is recorded, and storing the determination result in a memory for each track. A recording method determination method in a playback device.