JPH0626032B2 - Search method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Field of Industrial Application> The present invention relates to a search method, and more particularly to a search method suitable for finding a desired song in a digital audio tape device.

<Prior Art> A digital audio system in which a head is rotated while inclining relative to the longitudinal direction of a magnetic tape, digital audio data is digitally recorded on the magnetic tape by the head, and audio data is read from the magnetic tape and reproduced. There is a tape device (called an R-DAT device).

The rotary head configuration used in such an R-DAT device is
It has substantially the same structure as the rotary head in the VTR. That is, as shown in FIG. 4, two recording / playback heads HD1 and HD2 are arranged on the rotating body RB at intervals of 180 °, and the running loci of the heads HD1 and HD2 on the magnetic tape MT surface. Magnetic tape MT
The relative positional relationship between the magnetic tape and each head is determined so as to be inclined with respect to the longitudinal direction of the. And the rotating body R
Each time B rotates 180 °, the heads HD1 and HD2 alternately contact the magnetic tape MT for 90 ° to record audio data on the magnetic tape or read audio data from the magnetic tape.

In the R-DAT device, a signal CLC (T is a rotation cycle) synchronized with the rotation of the cylinder (rotary head) shown in FIG. 5 is synchronized with a contact between the head and the tape by a clock generator built in the signal processing circuit 11. Contact signal HT
C is generated, and signal processing and recording / reproduction processing are performed in synchronization with the signal. For example, in the case of normal reproduction, (a) When the head and the tape are in contact, that is, the in-contact signal HT
When C is at a high level (the period of T2 and T4), the audio data is read from the magnetic tape by the first and second heads HD1 and HD2, and the read audio data is supplied to the PLL circuit 11a.
To reproduce the clock signal and store the audio data in the RAM 11b in synchronization with the reproduced clock signal. (B) When the head and tape are not in contact
When TC is at a low level (during the period of T1 and T3), a read enable signal is generated to cause the processor 11c to perform error detection / correction and other processing on the audio data stored in the RAM, and perform DA conversion and output. . The head switching unit 12 switches the switch circuit 1 every half rotation based on a head switching signal HC from a head switching signal generating means (not shown).
3, the reproduction signals RS1 and RS2 from the first and second heads HD1 and HD2 are alternately switched to change the signal processing circuit 11
Function to type.

Further, the R-DAT device searches for a desired music piece by using the subcode data recorded in the subcode area of each track to find the desired music piece, or intro scan,
It has a function to perform other play at high speed. still,
The sub-code data is input from the signal processing circuit 11 to the sub-code processing circuit 14 and stored in the RAM 14a and then displayed by the processor 14b such as time code display, program number display, and search. Of these, the start of the desired song is detected by including the start ID indicating the beginning of the song in the subcode recorded in each track of the beginning of the song (track for 9 seconds at the beginning of the song). By doing so, the current song number is grasped and the desired song is searched. That is, if it is sent in the forward direction and the start ID is detected, the current song number is incremented by 1 (Ma + 1 → Ma), and if it is sent in the rewind direction and the start ID is detected, it is counted down by 1 (Ma−1 → Ma).
Ma), and when Ma becomes equal to the desired music number Ms, the search is completed and normal reproduction is performed thereafter.

<Problems to be Solved by the Invention> By the way, in the R-DAT device, it is necessary to perform play (playback) after the cue from the beginning of the start ID of the desired song.

However, in the conventional search method, the search completion point is within the start ID detection range, or the start ID detection range is too far in the reproduction direction, so that the reproduction can be performed accurately from the start of the start ID. There was a problem that I could not.

From the above, it is an object of the present invention to provide a search method capable of accurately searching for the beginning of a start ID in a short time and playing a desired song from the beginning of the start ID.

<Means for Solving Problems> FIG. 1 is a block diagram of an apparatus for realizing the present invention.

Reference numeral 21 is a start ID detection unit, 22 is a search control unit, and 23.
Is a tape feed control unit.

<Operation> If the start code is included in the subcode input from the signal processing circuit, the start ID detector 21 detects the start ID and outputs the signal SF.

The search controller 22 counts up the current song number Ma by 1 (Ma + 1 → Ma) if the signal SF is generated while sending in the forward direction, and counts down 1 if it detects the start ID while sending in the rewind direction ( Ma-
1 → Ma) to monitor the current song number.

If there is a search request, the search control unit 22 compares the size of the current music piece number Ma with the size of the desired music piece number Ms, and if Ma <Ms, the tape feed control section 23 is used to fast forward the tape in the forward direction. Then, the desired song is searched.

On the other hand, in the case of Ma> Ms, the tape is sent in the fast-forward direction in the rewind direction to search for the desired song. Then, when the start ID of the desired song is detected, the tape feed is stopped, and it is checked whether the stop position is within the start ID detection range. If it is within the start ID detection range, the tape feed control unit 23 is operated. The tape is fed in the rewind direction at a first speed that is slower than the fast-forward speed but higher than the normal playback speed, and normal playback feed is performed in the forward direction after the start ID is no longer detected.

Further, if the stop position is outside the start ID detection range, it is fed at the second speed (the first speed or a speed close thereto) in the rewind direction or the forward direction until the start ID is detected. The feed is performed in the rewind direction at the speed of, and the normal reproduction feed is performed after the start ID is not detected.

<Embodiment> FIG. 1 is a block diagram of an apparatus for implementing the present invention.

Reference numeral 21 is a start ID detector, 2 is a search controller, and 23 is a tape feed controller.

FIG. 2 is a schematic diagram of music number search according to the present invention, and FIG.
The figure is a flow chart of the process of the present invention.

The music piece number search process of the present invention will be described below with reference to FIGS.

The start ID detector 21 checks whether or not the subcode input from the signal processing circuit (not shown) includes the start ID, and if it does, the built-in flip-flop is set and the signal SF (see FIG. Output). The flip-flop is reset when the start ID is not included in the subcode. And
The signal SF lasts for about 9 seconds.

If the signal SF is generated while the tape is being sent in the forward direction, the search control unit 22 detects the rising of the signal SF and counts up the current music piece number Ma by 1 (Ma + 1 → M).
a), if the start ID is detected when sending in the rewind direction, the countdown is 1 (Ma-1 → Ma) in the same manner.
Then, the current song number Ma is monitored. Now, (a) When a search request for the desired music piece number Ms is generated, the search control unit 22 compares the current music piece number Ma with the size of the desired music piece number Ms.

(b) When Ma <Ms, the search control unit 22 causes the tape feed control unit 23 to feed the tape fast forward in the forward direction (FF search).

(c) During the FF search, if the start ID detector 21 detects the start ID and generates the signal SF, the search controller 2
2 increments the current song number by 1 (Ma + 1 → M
a). Then, it is checked whether Ma = Ms, and Ma
If ≠ Ms, the FF search after step (b) is continued.

(d) If Ma = Ms, in other words, if the start ID of the desired song is detected, the search control unit 22 causes the tape feed control unit 23 to stop the tape feed.

(e) After that, the tape is fed in the rewind direction at a review speed, which is slower than the fast-forward speed but faster than the normal playback speed (see FIGS. 2B and 2C) .. REV search.

(f) Then, signal S while feeding the tape at the review speed
Check whether F becomes high level ("H").

As shown in FIG. 2B, the stop position is the start ID.
If it is within the detection range SDR (the range where the signal SF is at the high level), the process immediately proceeds to the next step. But FF
When the start ID detection range SDR is stopped too much during the search (see FIG. 2 (C)), SF = “H” after moving in the amount rewind direction indicated by OVR.

(g) After that, the movement in the rewind direction continues at the review speed, and during this period, it is checked whether the start ID detection range SDR has been passed, in other words, whether SF = "L" has been reached.

(h) When the start ID detection range SDR is passed, the search control unit 22 causes the tape feeding control unit 23 to temporarily stop the tape feeding.

(i) After that, the tape is sent in the reproduction direction at the normal reproduction speed (PLY search).

(j) While feeding the tape at the normal reproduction speed, it is checked whether the start ID detection range SDR has been reached, in other words, whether the signal SF has become high level, and if the start ID detection range SDR is reached, mute is performed. Cancel and start normal playback.

(k) On the other hand, in step (a), if Ma> Ms, the search control unit 22 causes the tape feed control unit 23 to feed the tape in the fast-forward direction in the rewind direction to search for the desired song (REW search). ). In addition, prior to the REW search,
The search control unit 22 sets Ma + 1 → Ma.

(l) After that, the start ID detection unit 21 starts the start ID.
When the signal SF is detected and the signal SF is generated, the search control unit 22 counts down Ma (Ma-1 → Ma). Then, it is checked whether Ma = Ms, and if Ma ≠ Ms, the REW search is continued.

(m) If Ma = Ms, in other words, if the start ID of the desired song is detected, the search control unit 22 causes the tape feed control unit 23 to stop the tape feed.

(n) Then, it is checked whether the signal SF is at a high level ("H"). If it is at a high level (see FIG. 2 (E)), the process immediately proceeds to step (q).

(p) On the other hand, if the level is not high, the tape is sent in the forward direction at a queue speed that is slower than the fast-forward speed but faster than the normal playback speed (see FIG. 2 (F)).
UE search.

While feeding the tape at the cue speed, it is checked whether the signal SF has become high level ("H"). When the signal SF becomes high level ("H"), the tape feeding is stopped at the queue speed, and the process proceeds to the next step (q).

Therefore, as shown in FIG. 2 (E), if the stop position is within the start ID detection range SDR (within the range where the signal SF is at a high level), "YES" is determined in the step (n), and immediately the next step ( Go to q). However, as shown in FIG. 2 (F), if the start ID detection range SDR is exceeded and stopped, SF = “H” after moving in the forward direction at the amount queue speed indicated by OVR ′.

(q) After that, the tape is fed in the rewind direction at the review speed until SF = "L" (Figs. 2 (E) and (F)).
REV search.

Then, if SF = “L”, the processes after step (h) are repeated.

(r) In step (a), if Ma = Ms, it is checked whether the current stop position is within the start ID detection range SDR, in other words, whether the signal SF is at high level.

If the signal SF is at the high level, the process immediately jumps to step (q) to perform a review search, and then the processing from step (g) is performed (see FIG. 2 (D)).

(s) In step (r), if the stop position is outside the start ID detection range, REW search is performed until the signal SF becomes high level.

(t) Then, the signal SF is reached when the start ID detection range is reached.
If becomes a high level, the process skips to step (m) to stop the tape feeding, and then the process from step (n) is performed.

In the above, the case where the present invention is applied to the R-DAT device has been described, but it goes without saying that the present invention can also be applied to the fixed head type. The review speed and the cue speed are equal, but they need not be equal.

<Effects of the Invention> As described above, according to the present invention, the current music piece number Ma and the desired music piece number Ms are compared in size, and if Ma <Ms, the desired music piece number is searched by fast-forwarding in the forward direction, and Ma> Ms In this case, a search is performed in the fast forward direction in the rewind direction, and when the start ID of the desired song is detected, the search is stopped, and the stop position is the start ID
It is checked whether it is within the detection range. If it is within the start ID detection range, it is slower than the fast-forward speed, but is sent in the rewind direction at a review speed (first speed) higher than the playback speed, and the start ID is no longer detected. Then, normal reproduction feed is performed, and if the stop position is outside the start ID detection range, the feed is continued until the start ID is detected at the first speed or the second speed close to the first speed. Since the normal reproduction feed is performed after the start ID is not detected at the speed of 1, the start ID is not detected. Therefore, the start ID of the start ID is searched accurately and in a short time, and the desired start ID is obtained from the start ID of the start ID. The song can be played normally.

Further, according to the present invention, even if the stop position after the fast-forward search is outside the start ID detection range, the stop position is moved once within the start ID detection range, and then the stop position after the fast-forward search is detected within the start ID detection range. Since the reproduction is performed by the same control as in the case of (1), the reproduction can always be performed accurately from the beginning of the start ID regardless of the stop position after the fast-forward search.

[Brief description of drawings]

FIG. 1 is a block diagram of an apparatus for implementing the present invention, FIG. 2 is a schematic diagram of a search by the method of the present invention, FIG. 3 is a flow chart of processing of the present invention, and FIGS. 4 and 5 are R-DAT devices. FIG. 7 is an operation explanatory diagram of FIG. 21 ... Start ID detection unit, 22 ... Search control unit, 23 ... Tape feed control unit

Claims (1)

[Claims] 1. A sub-code data including a start ID indicating the beginning of a song is recorded on a magnetic tape together with voice data, and the current song number is grasped by detecting the start ID to search for a desired song. In the search method to be performed, the size of the current song number Ma and the desired song number Ms are compared, and Ma <M
In the case of s, the desired song number is searched by fast-forwarding in the forward direction, and in the case of Ma> Ms, the search is performed by fast-forwarding in the rewind direction, and when the start ID of the desired song is detected, the stop position is It is checked whether it is within the start ID detection range. If it is within the start ID detection range, the start ID is not detected because it is sent in the rewind direction at the first speed which is slower than the fast-forward speed but higher than the playback speed. If the stop position is outside the start ID detection range, it is fed at the first speed or the second speed close to the start speed in the rewind direction or the forward direction until the start ID is detected, and then the start is started. After the ID is detected, it is sent in the rewind direction at the first speed, and normal playback is sent after the start ID is no longer detected. Search method to collect.