JPH0244591A - Digital signal recording and reproducing device - Google Patents

Abstract

PURPOSE:To facilitate a retrieval to reach target absolute position information at an ordinary reproduction speed during a high speed reproduction by storing in a storing means the pair of block discrimination information corresponding to respective data blocks passing through a target data block during a retrieval and the absolute position information corresponding to the head frame of the block. CONSTITUTION:One frame by plus and minus azimuth trucks is previously formed on a tape 3 and absolute position information 10-1n to discriminate a frame unit with making the frame into a reference and data block information B1 being the discrimination information of the data block with one frame are formed. The information of the tape 3 is reproduced at heads 5a and 5b with the action of a mechanical control part by an instruction from a system control part 12, position information 1o-1n are inputted to an absolute position information recording and reproducing part 9 through a signal processing part 7 and the block information B1 is inputted to a data block discrimination information recording and reproducing processing part 8. Respective position information 1o-im and the block information B1 are processed and stored in the storing means.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a digital signal recording and reproducing apparatus that uses a rotary head to retrieve data recorded on a tape at high speed.

BACKGROUND OF THE INVENTION In recent years, digital recording and reproducing technology has come to be applied to a wide range of fields, and in particular, has made remarkable progress in the field of digital audio, with rotary head type % type % (AT) and the like being put into practical use.

On the other hand, attempts have been made to utilize DAT and apply it to auxiliary recording devices for computers. Instead of digitized audio data, these devices convert digital data provided from a computer into a predetermined amount of data in a preset data format.
It records data in sequence for each lock, reads digital data during normal playback, and outputs it as a data block, making it possible to record, playback, and save extremely large amounts of data. In addition, during the search operation, as in the case of audio applications, the program number that identifies the data block is read out from the sub data area at high speed, and the recording position of the target data block is searched to find the beginning of the target data block. It has been devised so that it can be taken out.

Problems to be Solved by the Invention However, in the above-mentioned conventional configuration, in order to search for high-speed playback using program numbers, it is necessary to search for the program number corresponding to the target data block and stop the target data block. The problem is that if you go too far past the first frame, you have to rewind by the amount you went too far and search for the first frame, which takes time. It cannot be determined whether a data block exists in the forward or backward direction of the tape, and the tape must be rewound and the search started from the beginning, which takes time. I was living with this problem.

The present invention solves the above-mentioned conventional problems, and aims to provide a digital signal recording/reproducing apparatus that searches for the first frame of a target data block at high speed.

Means for Solving the Problems In order to solve the above problems, the digital signal recording and reproducing apparatus of the present invention provides absolute position information that identifies a frame unit based on a frame formed in advance on a tape, and a plurality of frames. a recording means for recording data block identification information for identifying a data block to be formed in a predetermined specific area on a certain track; a reproduction means for intermittently reproducing; a first comparison means for comparing data block identification information reproduced by the reproduction means with target data block identification information of a target data block; and a first frame of the target data block. , or absolute position information targeting a frame near the first frame,
a second comparison means for comparing the absolute position information reproduced by the reproduction means; and a search means for searching for the target data block based on the comparison result of the first comparison means or the second comparison means. a storage means for storing search information that is a pair of data block identification information reproduced by the reproduction means and absolute position information corresponding to the data block identification information; and a storage means for storing the target data block identification information as a pair. and setting means for searching the search information stored in the search information and setting the absolute position information corresponding to the target data block identification information in the second comparing means as the target absolute position information. .

According to the above-described configuration, the present invention stores a pair of data block identification information corresponding to each data block passed during a search for a target data block and absolute position information corresponding to the first frame of the data block in a storage means. It has a learning ability by storing, and when the target data block is already stored in the storage means, the search is performed based on the target absolute position information corresponding to the first frame of the target data block. A single search can be performed without going too far into the first frame of the data block.

Embodiments Hereinafter, embodiments of the digital signal recording and reproducing apparatus of the present invention will be described with reference to the drawings.

First, FIG. 1 shows the configuration of a digital signal recording and reproducing apparatus in one embodiment of the present invention.

In Figure 1, 1 is a cassette half, 2 is a reel, and 3 is a cassette half.
4 is a tape, 4 is a cylinder, 5a and 5b are heads, 6 is a mechanism control unit that controls the operation of the reel 2 and cylinder 4, and 7 is a recording operation that encodes a digital signal and supplies the recording signal to the heads 5a and 5b. In the playback operation, a signal processing section 8 decodes the playback signals obtained from the heads 5a and 5b and outputs a diptal signal, and in the recording operation, 8 is a signal processing section that sends data block identification information, which is data block management information, to the signal processing section 7. 9 is a data block identification information recording/reproducing control unit which supplies the data block identification information to the signal processing unit 7 in the recording operation and extracts the data block identification information from the signal processing unit 7 in the reproduction operation; 9 supplies absolute position information to the signal processing unit 7 in the recording operation; An absolute position information recording and reproducing control unit extracts the absolute position information from the signal processing unit 7, and 10 stores search information consisting of a pair of data block identification information and absolute position information corresponding to the first frame of the data block. It is a search information storage section, and 11 is a communication section that transmits and receives digital data to and from an external device. 12, in the recording operation, the data block identification information is transmitted to the data block identification information recording/reproducing control unit 8.
or absolute position information is sent to the absolute position information recording/playback control unit 9, and in the playback operation, the data block identification information obtained by the data block identification information recording/playback control unit 8 and the data block identification information obtained by the absolute position information recording/playback control unit 9 are used. Extract absolute position information,
Search information consisting of a pair of the extracted data block identification information and the absolute position information corresponding to the first frame of the extracted data block is stored in the search information storage unit 10, and in the search operation, the extracted absolute position information and the search A system that compares the absolute position information corresponding to the data block of the target data block among the search information stored in the information storage unit 10, sends tape speed information to the mechanism control unit 6, and searches for the target data block. This is the control section.

The operation of the digital signal recording/reproducing apparatus of this embodiment configured as described above will be explained below. Prior to the explanation, FIG. 2 shows the tape format. One frame consists of an adjacent positive azimuth track and a negative azimuth track, and each track has a main data area for recording digital data,
A sub-data area located on both sides of the sub-data area for recording auxiliary data and a track synchronization signal (ATF)
e Track Finding) area.

First, the recording operation will be explained in detail. In the recording operation, absolute position information and data block identification information are recorded in the sub data area, and user data given via the communication means is recorded in the main data area. First, the absolute position information is determined by setting the absolute position information of the 0th frame, which is a reference, to 10,n in Fig. 3 showing the frame arrangement of the tape.
Let In be the absolute position information of the th frame. Further, the data block identification information is the identification information of a data block formed from a certain plurality of frames in FIG. 4, and is designated as B9. Next, in FIG. 1, the data block identification information recording/playback control section 8 and the absolute position information recording/playback control section 9 give operation commands to the mechanism control section 6 via the system control section 12 to drive the mechanism. , data block identification information and absolute position information are transferred to the signal processing section 7 and recorded in the sub data area for each frame via the head 5 al 5 b.

Next, the playback operation will be explained in detail. In FIG. 1, the absolute position information recording and reproducing control section 9 and the data block identification information recording and reproducing control section 8 give operation commands to the mechanism control section 6 via the system control section 12 to drive the mechanism, and also to drive the mechanism. Absolute position information and data block identification information in the data area are extracted via the head 5 at 5 b, and the absolute position information is sent from the signal processing unit 7 to the absolute position information recording/reproduction control unit 9, and the data block identification information is extracted from the data area. The identification information is input to the data block identification information recording/reproducing control section 8.

Next, the search operation for a certain data block will be explained in detail using the flowchart shown in FIG.

First, the system control unit 4 sets the mechanism to high-speed playback operation, starts the search, and proceeds to step (2).If the data block identification information of the data block to be searched exists in the search information storage unit, the system control unit 4 proceeds to step (2). If it does not exist, proceed to step ■.

First, a case will be described where the data block identification information of the data block to be searched does not exist in the search information storage section. In step (2), if the reproduced frame is the first frame of the data block, the process advances to step (2), and if it is not the first frame, the process of step (2) is repeated again. Next, in step (2), a pair of reproduced data block identification information and absolute position information corresponding to the data block identification information is stored in the search information storage section 10. Next, proceed to step ■, and if the new data block matches the data block to be searched, stop high-speed playback and rewind the tape by the amount that was exceeded until the data block to be searched is reached at normal speed and the search is resumed. finish.

Next, a case where data block identification information of a data block to be searched exists in the search information storage section will be described.

First, the process proceeds to step (2), where it is determined whether the position of the data block to be searched for in the tape running direction is in the forward direction or in the reverse direction, and high-speed playback is started in the determined direction. Next, the process proceeds to step (2), and if the absolute position information corresponding to the data block to be searched matches the reproduced absolute position information, the search ends. If they do not match, the process proceeds to step (3), where the difference between the absolute position information corresponding to the data block to be searched and the reproduced absolute position information is determined, and speed control is performed in accordance with the difference. For example, when the difference is large, the playback is performed at high speed, and as the difference becomes smaller, the playback speed is decelerated toward the normal playback speed. In this way, steps (2) and (2) are repeated, deceleration is started from before the data block to be searched, the data block to be searched is reached by normal reproduction, and the search is completed.

Note that although the mechanism control unit 6, data block identification information recording/playback control unit 8, absolute position information recording/playback control unit 9, and system control unit 12 are each independent control units, several of these are integrated into a microcomputer. It may also be implemented as software.

Further, in the absolute position information recording/reproducing control section 9 of this embodiment, the absolute position information is set in units of frames, but the absolute position information may be set in units of tracks.

As described above, according to this embodiment, data blocks that are frequently searched can be searched at high speed.

Effects of the Invention As described above, the digital signal recording and reproducing apparatus of the present invention has the following advantages:
Absolute position information for identifying frame units based on pre-formed frames on the tape and data block identification information for identifying data blocks formed from multiple frames are stored at a predetermined location on a certain track. a recording means for recording in the area; a reproducing means for reproducing the plus azimuth track and the minus azimuth track continuously or intermittently at normal speed or high speed;
a first comparison means for comparing the data block identification information reproduced by the reproduction means and the target data block identification information of the target data block; and a first frame of the target data block or a frame near the first frame; A second comparison means for comparing the absolute position information aimed at and the absolute position information reproduced by the reproduction means, and the comparison result of the first comparison means or second comparison means a search means for searching for a target data block; a storage means for storing search information consisting of a pair of data block identification information reproduced by the reproduction means and absolute position information corresponding to the data block identification information; Searching for target data block identification information from the search information stored in the storage means, and setting absolute position information corresponding to the target data block identification information in the second comparing means as the target absolute position information. By providing a setting means for setting the target data block, it is easy to judge whether the target data block identification information is in the forward direction or the reverse direction with respect to the tape running direction, and the target absolute position information is set at the normal playback speed during high-speed playback. Easy to search to reach. In addition, there is no need to record a huge amount of search information over the entire tape, the tape is used more efficiently, and the memory of the device is small, so it is easy to implement at low cost, and the configuration is simple. It has some characteristics.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of a digital signal recording/reproducing device, Fig. 2 is a block diagram of a tape format, Fig. 3 is a frame block diagram showing absolute position information on a tape in an embodiment of the present invention, and Fig. 4 is a block diagram of a tape format. FIG. 5 is a frame configuration diagram showing the data block identification information on the tape in the embodiment of the present invention. FIG. 5 is a flowchart showing the control procedure of the system control section 12 in the embodiment of the present invention. 1...Cassette half, 2...Reel, 3...Tape, 4...
・Cylinder, 5a, 5b...Head,
6...Mechanism control section, 7...
・Signal processing unit, 8... Data block identification information recording/playback control unit, 9... Absolute position information recording/playback control unit, 10... Search information storage unit, 11.・・・・・・Communication Department, 12・・・・・・
System control unit. Name of agent: Patent attorney Shigetaka Kurino (1 person) Figure 1 Figure 3 Beak - 1 - Tape shortage ↑ 紮 を しょょう n Figure 2 Figure 4 Figure ヂ'-Dub'8-t7f

Claims (1)

[Claims] (1) Absolute position information for identifying frame units and data blocks for identifying data blocks formed from multiple frames, based on a frame consisting of a positive azimuth track and a negative azimuth track formed in advance on the tape. a recording means for recording identification information in a predetermined specific area on a certain track; and a recording means for recording identification information in a predetermined specific area on a certain track, and reproducing a plus azimuth track and a minus azimuth track continuously at a normal speed or intermittently at a high speed. a first comparison means for comparing the data block identification information reproduced by the reproduction means and the target data block identification information of the target data block; A second comparison means for comparing absolute position information targeting a frame near the frame with the absolute position information reproduced by the reproduction means, and a comparison between the first comparison means or the second comparison means. A search means for searching the target data block based on the result, and a storage means for storing search information that is a pair of data block identification information reproduced by the reproduction means and absolute position information corresponding to the data block identification information. The target data block identification information is searched from the search information stored in the storage means, and the absolute position information corresponding to the target data block identification information is sent to the second comparison means to determine the target absolute position. 1. A digital signal recording and reproducing device comprising a setting means for setting information.