JPH0563867B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a search method, and particularly to a search method in a DAT device (digital audiotape device).

<Prior art> A DAT device has a function of searching for and playing a desired song using a start ID indicating the beginning of the song. That is, a start ID indicating the beginning of the song is included in each track at the beginning of the song (a track for 9 seconds at the beginning of the song), and each time the start ID is detected, the current song number is updated and the desired song is searched. The desired song is searched by determining the current song number from the program number (music number) recorded in the subcode area when the start ID is detected.

By the way, in the conventional method of searching using a start ID, for example, the search is performed in the forward direction by fast forwarding (FF in FIGS. 6B and C).
), when the start ID of the desired song is detected (signal SFR = “H”), the tape is stopped, then fed in the rewind direction at the review speed (REV), and after the start ID is no longer detected, the tape is started at the play speed. Send it in the forward direction (PLY), and when the start ID is detected, release the Miyuto and start playing.

In addition, when feeding the tape by fast forwarding in the rewind direction, first detect and stop the start ID of the desired song by fast forwarding in the rewind direction (see REW in D and E in Figure 6), and then start at the queue speed. Send in the forward direction (CUE) until the ID is detected, then send in the rewind direction at the review speed (REV), and after the start ID is no longer detected, feed at the play speed (PLY), and detect the start ID. to release Miyuto.

<Problems to be solved by the invention> In the conventional search method, it is necessary to reverse the tape feeding direction several times after detecting the start ID of the desired song until canceling mute, which reduces the search time. The problem is that it is long.

From the above, an object of the present invention is to shorten the search time.

Another object of the present invention is to overcome the conventional search method of searching for a desired song using a start ID.
The present invention is to shorten the overall search time by appropriately combining a search method in which a desired song is searched using an absolute time without using a search method.

<Means for Solving the Problems> FIG. 1 is a block diagram of a device that implements the search method according to the present invention.

11 is a recording/reproducing head, 12 is a signal processing section,
13 is a control microcomputer, 14 is an operation panel, 15 is a tape feed control section, and 16 is a tape running mechanism section.

<Operation> In response to a search request, the controller microcomputer 13 determines whether the absolute time of the song number for which the search request was made is known, and if it is known, performs a search using the absolute time, and if not, performs a search using the start ID. .

<Embodiment> FIG. 1 is a block diagram of an apparatus for realizing a search method according to the present invention, and FIGS. 2 to 5 are flowcharts of search processing according to the present invention.

In FIG. 1, 11 is a recording/playback head (actually two recording/playback heads are provided), 1
2 is a signal processing section, 13 is a control microcomputer,
14 is an operation panel equipped with a search key 14a, a numeric keypad 14b, etc.; 15 is a tape feed control unit;
is the tape running mechanism.

The signal processing unit 12 converts the audio data read from the magnetic tape by the recording/reproducing head 11 into a built-in
The digital audio data is stored in the RAM, and after error detection and correction and other processing are performed on the audio data, DA conversion is performed and output.Furthermore, the digital audio data is output to the recording/reproducing head 11 and written on a tape. In addition, the signal processing unit 12 receives TOC information for all songs written at the beginning of the tape, TOC information for each song written at appropriate locations on the tape, absolute time written in the subcode area, and start ID detection signal SF. etc. are output to the control microcomputer 13. The TOC information for all songs includes the number of songs, the playing time of each song, the total playing time, the correspondence between each song number and the absolute time of the song, etc., and is generally recorded on commercially available soft tapes. is written at the beginning of the .

The control microcomputer 13 is the processor 13
a, a program memory (ROM) 13b for storing various processing programs, and a RAM 13c, and is configured to perform search processing shown in FIGS. 2 to 5.

The overall operation of FIG. 1 will be explained below with reference to the flowcharts of FIGS. 2 to 5.

(a) Correlation process between track numbers and absolute times (see Figure 2) When the tape is fed by a play operation, the processor 13a of the control microcomputer 13 checks whether the TOC information of all tracks has been read (step 101).

If the TOC information can be read, the TOC information is read from the signal processing section 12 and stored in the RAM 13c (step 102), and play is thereafter executed (step 103). As a result of the above, the correspondence between the song numbers and absolute times of all songs is stored in the RAM 13c.

On the other hand, if the TOC information cannot be read, play is executed (step 104), and after that, in parallel with play, a check is made to see if TOC information for each song is detected or if a start ID is detected (step 105), and If the TOC information of
Reading TOC information from signal processing section 12
If the start ID is detected, the absolute time at that time is read from the signal processing unit 12, associated with the song number, and stored in the RAM 13c in the same way (step 106), and the processing from step 104 onwards is repeated. .

(b) Search processing (see Figure 3) Processor 13 of control microcomputer 13
For example, during play (step 201),
Check if there is a search request (step
202). Incidentally, a search request is generated by setting a song number on the numeric keypad 14b and pressing the search key 14a.

If no search request occurs, continue playing, and if a search request occurs, use RAM13c.
It is determined whether the absolute time of the desired song number set on the numeric keypad 14b is known by referring to the song number/absolute time correspondence table stored in the numeric keypad 14b (step 203).

If it is not known, a search process using the start ID shown in FIG. 4 is performed (step 204), and if it is known, a search process using the absolute time shown in FIG. 5 is performed (step 205), and after the search, play is performed ( Step 206).

(c) Search process using start ID (see Figures 4 and 6) In the determination process at step 203 in Figure 5,
If the absolute time of the track number requested for search is not known, the processor 13a of the control microcomputer 13 compares the current track number Ma with the desired track number Ms, and if Ma<Ms, controls the tape advance. 15 to rapidly feed the tape in the forward direction (referred to as FF search, step 301). Note that if it is Ma/Ms, a search is performed by rewinding, but the explanation will be omitted.

When searching for FF, the signal processing unit 12 uses the start ID.
When the processor 13a detects this and generates the signal SF (see FIG. 6A), the processor 13a increments the current song number by one (Ma+1→Ma). And Ma＝
Check whether Ms (step 302), Ma<Ms
If so, the FF search continues, and if Ma=Ms, in other words, if the start ID of the desired song is detected, the control microcomputer 13 causes the tape feed controller 15 to stop the tape feed (step 303). ).

Thereafter, it is checked whether it has stopped within the start ID detection range SDR (FIG. 6A), in other words, it is checked whether the signal SF is at a high level ("H") (step 304).

If signal SF is low level, start ID
The detection range SDR has been stopped by a predetermined amount OVR (see Figure 6 C), and the tape is then fed in the rewind direction at a review speed that is slower than the fast forward speed but faster than the play speed (referred to as REV search). In step 305), while feeding the tape at the review speed, it is checked in step 304 whether the signal SF has become high level ("H").

Then, when the signal SF becomes high level, or if the stop position in step 303 is within the start ID detection range SDR (see Figure 6B), the movement in the rewind direction at the review speed is continued (step 306). , whether the start ID detection range SDR was passed during this time, in other words
Check whether SF=“L” (step 307).

If SF=“L”, that is, if the start ID detection range SDR is passed, the control microcomputer 13 causes the tape feed controller 15 to temporarily stop tape feed (step 308).

Thereafter, the tape is sent in the forward direction (playback direction) at the play speed (PLY search, step 309). Then, while feeding the tape at the play 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.
310), when the start ID detection range SDR is reached, the mute is canceled and playback is started.

(d) Search by absolute time (see Figure 5) In the determination process at step 203 in Figure 5,
If the absolute time As of the track number for which the search request has been made is known, the processor 13a of the control microcomputer 13 reads the current absolute time Aa from the signal processing unit 12, and
The absolute time Aa is compared with the absolute time As of the desired track number, and the tape feed control section 15 is controlled depending on the size, and the tape is rapidly fed in the forward or rewind direction (step 401).

Then, during the search by fast forwarding, the time difference T between the current absolute time Aa and the first absolute time As of the desired track number is determined (step
402), it is checked whether the time difference T has become smaller than the preset first deceleration start time T _D1 (step 403), and if T _D1 < T, step 401 is performed.
The subsequent fast-forward search continues, and if T _D1 ≧T, the tape feed control section 15 decelerates the tape feed speed to a predetermined first speed V _D1 (step
404), the search will be performed at that speed from now on (step
405).

Current absolute time Aa during low speed search
It is checked whether the time difference T between the start absolute time As of the desired track number has become less than the second deceleration start time T _D2 (step 406), and if T _D2 < T, the low-speed search from step 405 onwards is continued,
If T _D2 ≧T, the tape feed control section 15 decelerates the tape feed speed to a predetermined second speed V _D2 (for example, the play speed, where V _D2 < V _D1 ) (step 407). A search is performed at the second speed (step 408).

Then, during the search using the second speed, it is determined whether the current absolute time Aa and the starting absolute time As of the desired track number match (step 409). If they do not match, the search using the second speed is continued to find a match. If you do this, you can release Miyuto and start playing.

<Effects of the Invention> According to the present invention, when the correspondence between the song number and the absolute is known, a search is performed using the absolute time, and when it is not known, the search is performed.
Since the configuration is configured to search by ID, the search can be performed by absolute time, which can shorten the search time, so the overall search time can be shortened.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a device implementing the search method according to the present invention, FIGS. 2 to 5 are flowcharts of the search process of the present invention, and FIG. 6 is an explanatory diagram of the search process using a start ID. 11... Recording/playback head, 12... Signal processing section, 13... Control microcomputer, 14... Operation panel, 15... Tape feed control section.

Claims (1)

[Claims] 1. A start ID indicating the beginning of a song and an absolute time from the beginning of the tape are recorded on a magnetic tape together with audio data, and the correspondence between the song number and the absolute time at the beginning of the song number is determined. Each time a song is found, the corresponding correspondence is stored in memory, and a search request is made to determine whether the absolute time of the song number for which the search request was made is known. If it is known, a search is performed using the absolute time, and if it is not known, A search method characterized by searching by start ID.