JPH0664835B2 - Repeat playback method - Google Patents

Description

The present invention relates to a repeat reproduction system, and more particularly to a repeat reproduction system in a device including a digital signal processor (hereinafter abbreviated as DSP).

<Prior Art> An analog tape player, a CD player, and a DAT device have a function of repeatedly reproducing and outputting the same song (repeat reproducing function).

<Problems to be Solved by the Invention> With such a conventional repeat playback method, it is inconvenient when it is not possible to repeat playback from an arbitrary position desired by the user and it is repeated many times from the middle like English conversation. there were.

Also, in the conventional repeat and playback system, it is necessary to move the signal reading section (head, pickup, etc.) to the beginning of the part to be repeatedly played, so the audio signal source is damaged (especially analog tape, DAT tape), and the signal is read. There is a problem that it takes time to move the part to a desired place and it takes time to start the repeat reproduction.

From the above, the object of the present invention is not required to move the reading unit to the repeat reproduction start position, therefore does not damage the recording source, and promptly if a repeat reproduction request is made,
Moreover, it is to provide a repeat reproduction system capable of reproducing any number of times from an arbitrary position.

<Means for Solving Problems> According to the present invention, the above object is to provide a digital signal processor for performing predetermined signal processing on a digital audio signal, and various coefficients and DSP processing required for processing of the digital signal processor. A memory that stores the result and the digital audio signal, a DA converter that converts the digital audio signal to an analog signal, a data switch that inputs the digital signal processor output and the memory output, and inputs one of them to the DA converter. , A memory control means for controlling reading / writing of data from / to the memory, and an operation panel having a repeat reproduction key, a memory stop key, a repeat end key, and the like.

<Operation> Normally, the output of the digital signal processor is
When DA conversion is performed and output, and the repeat playback key is operated,
The memory control means inputs a digital audio signal into the memory and starts storing, and stores the audio signal in the memory until the memory stop key is operated or until the memory is full, and after the storage is completed, the memory control means Read the audio signal from the memory and through the data switch
The operation of inputting into the DA converter, DA converting with the DA converter and outputting is repeated until the repeat end key is operated.

<Example> FIG. 1 is a block diagram of a digital amplifier to which the present invention is applied.

Reference numeral 11 is an AD converter that converts the analog audio signal S _A input from an audio source (not shown) into digital data S _D , and 12 is subjected to predetermined digital processing using coefficient data every time digital data is input, and output A digital signal processor (DSP), 13 is a DA converter that DA-converts digital audio data into an analog audio signal, 14 is various coefficient data necessary for DSP processing, and DSP processing results are stored, and in a repeat playback state. Is a large-capacity RAM that stores the digital audio data _SD output from the AD converter 11, 15 is a repeat control unit that controls repeat playback control, and 16 is an address bus and data bus in the normal signal processing state and repeat playback state. A bus switch for switching the connection of the, 17 is a device for outputting according to the normal signal processing state and the repeat playback state. Data switch for switching the barrel data, 18 denotes an operating panel, repeat playback key, a memory stop key 18b, variable irregular playback key 18c,
A repeat end key 18d and the like are provided.

In the normal signal state, the bus switcher 16 operates at the address A1.
And the address bus ABS are connected, the data bus D1 and the data bus DBS are connected, and the RAM 14 is connected to the DSP 12. Further, the data switching device 17 inputs the digital data S _D ′ output from the DSP 12 into the DA converter 13. Therefore, DS
The P12 reads predetermined coefficient data for each characteristic from the RAM 14 and digitally processes the input digital data S _D , and outputs the processed digital data S _D ′ to change various properties.

In such a signal processing state, when the repeat reproduction key 18a is pressed, the repeat control unit 15 outputs the switching signal BSC1 to connect the address bus A2 and the address bus ABS, and between the data bus D2 and the data bus DBS. Connect and DSP
Disconnect the connection between 12 and RAM14.

Then, the repeat control unit 15 thereafter synchronizes with the write command and the RAM 1 in synchronization with the sampling clock of the digital data S _D.
4 address data is generated, and the digital audio data S _D output from the AD converter 11 is stored in the RAM 14. still,
While storing digital audio data _SD in RAM14, DSP12
Outputs the digital data S _D as it is or after performing predetermined processing as digital data S _D ′, and this digital data S _D ′ is output via the data switcher 17.
It is input to the DA converter 13, where it is DA converted and output.

When the memory stop key 18b is pressed during the storage in the RAM 14 or the predetermined storage area of the RAM 14 is completely used up, the repeat control unit 15 generates the switching signal BSC2 and causes the bus switching unit 16 to operate the data bus. The D3 and the data bus DBS are connected to each other, and the data switching unit 17 is used to selectively output the digital data on the bus D3. The analog source is in the paused state.

Thereafter, the repeat control unit 15 generates a read command and sequentially generates address data on the address bus A2 with a sampling clock, and continuously outputs digital audio data stored from the RAM 14 to the data bus D3.
The data is input to the DA converter 13 via the data switch 17, and the DA converted analog audio signal is output.
When the repeat reproduction is performed until the end, every time the repeat key 18a is pressed thereafter, the stored audio signal is similarly reproduced from the beginning to the end.

The playback speed can be changed by operating the variable speed playback key 18c.

The repeat end key 18d is pressed to return to the normal signal processing state after the above repeated reproduction operation. As a result, the bus switch 16 and the data switch 17 bring the connection into a signal processing state, and the above-mentioned signal processing is performed.

<Effects of the Invention> According to the present invention, since the digital audio data to be repeatedly reproduced is stored in the RAM, it is not necessary to move the reading unit to the reproduction start position, and thus the source is not damaged. Moreover, if there is a reproduction request, the reproduction can be performed promptly, and the repeat reproduction can be performed from an arbitrary position desired by the user.

Further, according to the present invention, when the repeat reproduction key is operated, the audio data is input to the memory to start the storage, and the audio data is stored in the memory until the memory stop key is operated or the memory is full. Remember
After the memory is stored, the data is read from the memory and repeatedly output. Therefore, by repeatedly operating the repeat key at the beginning of the part you want to hear truly, you can store it in the memory from the beginning and output it repeatedly. You can

Further, according to the present invention, since the memory already prepared for storing the processing result of DSP and the coefficient can be shared as the memory for storing the audio data, the cost can be reduced.

[Brief description of drawings]

The figure is a block diagram of a digital amplifier to which the present invention is applied. 11 …… AD converter, 12 …… digital signal processor (DSP), 13 …… DA converter, 14 …… RAM, 15 …… repeat control block, 16 …… bus switch, 17 …… data switch, 18 ... Operation panel

Claims (1)

[Claims] 1. A digital signal processor for subjecting a digital audio signal to predetermined signal processing, and a memory for storing various coefficients and DSP processing results necessary for processing of the digital signal processor and a digital audio signal.
DA that converts digital audio signals to analog signals
A converter, a digital signal processor output and a memory output are input, one of which is input to a DA converter, a memory control means for controlling reading / writing of data to / from the memory, a repeat playback key, and a memory stop. Equipped with an operation panel that has keys, repeat end keys, etc. Normally, the output of the digital signal processor is a DA converter.
When DA repeat conversion is performed and the repeat playback key is operated, the memory control means inputs the digital audio signal to the memory and starts storing, until the memory stop key is operated or the memory is full. The signal is stored in the memory, and after the storage is finished, the memory control means reads the audio signal from the memory, inputs it to the DA converter via the data switching device, DA-converts it in the DA converter, and outputs the signal. Repeat playback method characterized by repeating until a key is operated.