KR0137863B1 - Detecting method of curve edge - Google Patents

Abstract

A method of searching for a head position of a song in a digital audio tape recorder driving a digital audio tape recording subcode information including a start ID, the method comprising: a first step of checking whether a tape skip key is input; The second process of advancing the tape in a high speed forward direction and pausing when a rising edge is detected and detecting the rising edge, then reading the starting ID while advancing the tape in the medium speed reverse direction and changing the speed to the low speed forward direction when the falling edge is detected. And a third step of reversely skipping the key, reading the start ID while advancing the tape in a high speed reverse direction, pausing when the falling edge is detected, and reproducing the tape in the medium speed forward direction, and starting ID during the low speed forward progression. Is detected as 1 or the medium speed forward true If a rising edge of the start ID is detected in the row, the tape proceeds in a slow reverse direction, and when the start ID is read out and 0 is detected (the music head is found), a fourth process is started. It features.

Description

How to navigate the song head

1 is a schematic block diagram of a digital audio tape recorder to which the present invention is applied.

2 is a flowchart illustrating a song head search method according to an exemplary embodiment of the present invention.

Figure 3 shows the track format of a digital audio tape

4 is a subcode block format diagram of FIG.

* Description of the symbols for the main parts of the drawings *

10: key input unit 20: signal processing unit

30: microcomputer 40: servo unit

50: display unit

The present invention relates to a tape position search method in a digital audio tape (DAT) recorder, in particular a start-identification (hereinafter referred to as ST-ID) recorded on a tape. To quickly find the beginning of a song.

In general, you may want to listen to music and then listen to the song you are playing. However, the conventional cassette tape recorder has a disadvantage in that the search speed is slow because it searches with the presence or absence of radio frequency (RF) when searching for the beginning of a song.

In the DAT for converting and recording audio signals digitally, the necessity of searching for the beginning of a song is similarly raised, but it cannot be taken as a cassette tape recorder due to its characteristics.

Accordingly, an object of the present invention is to provide a method for searching for a song head portion of a DAT.

In order to achieve the above object, the present invention provides a method for searching for a head position of a song in a digital audio tape recorder driving a digital audio tape recording subcode information including an ST-ID. In the first step of checking and the forward skip key, the ST-ID is read while the tape is advanced in the high-speed forward direction, and when the rising edge is detected, the pause is paused. When the edge is detected, the second process of changing the speed forward in the forward direction and the reverse skip key reads the ST-ID while advancing the tape in the high speed reverse direction and pauses when a falling edge is detected, and then proceeds the tape in the medium speed forward direction again. And the ST-ID is detected as 1 during the low speed forward progress or the medium speed forward true When the rising edge of the ST-ID is detected, the fourth process starts the playback after a predetermined time elapses when the ST-ID is read while the tape is advanced in the reverse direction and 0 is detected (the song head is found). It is characterized by.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First of all, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals have the same reference numerals as much as possible even if displayed on different drawings. Also, in the following description, many specific details such as components of specific circuits are shown, which are provided to help a more general understanding of the present invention, and the present invention may be practiced without these specific details. It is self-evident to those of ordinary knowledge in Esau. In the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

In addition to the digital audio signal, the DAT can record various additional information such as, for example, subcode data, so that the head part of the song can be searched using this information.

1 is a schematic block diagram of a digital audio tape recorder to which the present invention is applied.

The microcomputer 30 collectively controls the overall operation of the DAT recorder, the key input unit 10 for inputting various commands and data, and the control of the microcomputer 30 to read and retrieve the corresponding code data from the tape. The signal processing unit 20 performs a signal processing operation according to a mode and transmits the signal processing result to the microcomputer 30, and drives the motor under the control of the microcomputer 30 to drive the DAT according to various modes. A servo unit 40 for controlling the operation and a display unit 50 for displaying various states of the DAT recorder under the control of the microcomputer 30 are included.

2 is a flowchart illustrating a music head search method according to an exemplary embodiment of the present invention.

3 is a diagram illustrating a track format of a DAT.

Set the Pulse Code Modulation (PCM) data area in the center of the track, and set the Auto Track Finding (ATF) areas for tracking on both sides, and again provide various information such as song number and time code on both sides. A sub code area that can be recorded is set. An interblock gap (IBG) is set between the regions, and each region can be independently rewritten by overwriting. By having a variety of information on the tape as described above, the microcomputer 30 can find the head part of the song by reading the subcode information recorded on the tape through the operation process according to FIG. .

4 illustrates a detailed structure of a subcode block of FIG.

4 is a subcode block format. When subcodes are classified, they can be broadly divided into PCM areas (PCM IDs) and subcode areas. The subcode areas are further divided into subcode IDs and subcode data, and the subcode IDs are divided into control IDs, data IDs, and the like. It is divided into Pack ID and PNO ID. In the present invention, the ST-ID, which is used as an index for searching the beginning of the song, is one of the information recorded in the control ID, and '1' means the beginning of the song or program, and '0' means the middle of the program. The ST-ID is recorded as '1' for 300 ± 30 frames from the beginning of the song.

4B is a classification diagram of the subcode ID in the subcode block. The subcode ID is recorded in W1 and W2 of the subcode area.

Hereinafter, a process of searching for a music head position using the ST-ID will be described with reference to FIGS. 1 to 4.

In step (a) of FIG. 2, the microcomputer 30 scans the key input unit 10 to check whether a predetermined key is input. If there is a key input as a result of the check, the process proceeds to step (b) to determine whether the key is a forward skip key. In this case, the forward skip is an operation for searching for the next song in the forward direction from the direction currently being played.

If it is confirmed that the forward skip key, the process proceeds to step (c) to control the signal processing unit 20 and the servo unit 40 to advance the tape in the high-speed forward direction. In step (d), it is determined whether the ST-ID read from the signal processor 20 is a rising edge. When the rising edge is detected as a result of the determination, the process proceeds to step (e) to control the servo unit 40 to stop the high speed forward movement of the tape. As described above, when the tape is advanced at high speed, the sub code is reproduced, but the audio signal is not reproduced. Therefore, if a point where the ST-ID is '1' is detected as a result of the high speed progression, it is recognized as the start position of the song, and from this time, the operation for finding the correct position is performed. The reason for doing the work to find the exact position is that if the tape advances at a high speed, even if the rising edge of the ST-ID is detected, it may slightly move out of position. Therefore, reduce the speed and advance the tape at medium speed, but the direction is reversed.

Specifically, after the stop operation in step (e), the process proceeds to step (f) to operate the signal processing unit 20 and the servo unit 40 in the medium speed reverse mode, and in step (g), the signal processing unit 20 ) Detects the falling edge of the ST-ID. When the falling edge is detected as a result of the irradiation, the process proceeds to step (h) to control the signal processing unit 20 and the servo unit 40 to operate in a low speed forward mode. The reason for taking the reverse direction at middle speed is to go back to find the position because the tape is moving forward more than the exact position. The reason for detecting the falling edge of ST-ID is to be forward because the tape is moving in the reverse direction. This is because the rising edge point at the time is detected as the falling edge.

After performing step (h), in step (i), it is determined whether the ST-ID is 1, and if it is 1, the process proceeds to step (j) to advance the tape in a low speed reverse direction. The unit 40 is operated in a low speed reverse mode. Subsequently, in step (k), the signal processor 20 determines whether the ST-ID is '0'. If the value is '0', this means that the music is at the beginning of the song. After elapse of), the process proceeds to step (m) to terminate the search operation by operating the signal processing unit 20 and the servo unit 40 in the regeneration mode. It is also possible to switch directly from the medium speed mode to the playback mode without going through the low speed mode. However, switching from the low speed mode to the playback mode as described above may be more stable in the mechanism than switching from the medium speed mode to the playback mode. Because it can be fast.

On the other hand, if it was not the forward skip in step (b), go to step (n) to check whether or not the reverse skip key, and if not the reverse skip key, the operation is terminated. However, if it is confirmed in step (n) that the reverse skip key, the reverse skip is to find the beginning of the song currently being reproduced, so proceed to step (o) and the signal processing unit 20 and the servo unit 40 Operate in fast reverse mode.

After performing step (o), the signal processor 20 operating in the fast reverse mode is checked to determine whether the falling edge of the ST-ID is detected. If the falling edge is detected as a result of the check, the process proceeds to step (q) to stop the progress of the tape once, and in step (r), the servo part 40 is controlled to allow the tape to proceed in the medium speed forward direction and at the same time the signal The processor 20 controls the processor 20 to check whether an ST-ID rising edge is generated in step (s). If the ST-ID rising edge is detected as a result of the check, the process proceeds to step (j) to switch the tape advance mode to the low speed reverse direction as described above, and then to play after a predetermined time elapses.

As described above, by reading the ST-ID of the sub-code recorded on the digital audio tape so that the head position of the song can be quickly found, not only can it be easily used, but also the function of the system requiring diversification is improved. Even has the advantage to play a role.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined not only by the scope of the following claims, but also by those equivalent to the scope of the claims.

Claims (1)

A method of searching for a beginning position of a song in a digital audio tape recorder which drives a digital audio tape having recorded subcode information including a start ID, A first step of checking whether a tape skip key is input, In case of forward skip key, the start ID is read out while the tape advances in the high speed forward direction, and when the rising edge is detected, it is paused, and the start ID is read out while the tape is advanced in the medium speed reverse direction. The second process of letting A third step of reversing the tape in a high speed reverse direction while reading the start ID and pausing when the falling edge is detected by the reverse skip key; When the start ID is detected to be high during the low speed forward progress or the rising edge of the start ID is detected during the medium speed forward progress, the start ID is read while the tape is advanced in the low speed reverse direction, and when the low state is detected, playback is performed after a predetermined time. Song head searching method characterized in that the fourth process to start.