JPH0218756A - Level setting device - Google Patents

Abstract

PURPOSE:To automatically set an optimum recording level even at the time of analog recording by constituting a level setting device of an A/D converter, which executes the A/D conversion of an analog input signal, and a level control part to control the level of the analog input signal so that relation between first and second level data to be outputted from first and second level detecting parts can satisfy a specified condition. CONSTITUTION:An A/D converter 102 converts the analog input signal to a digital signal. Next, a first level detecting part 104 detects the level of digital data ADDAT, which are outputted by the A/D converter 102, and outputs analog input level data ALV. A second level detecting part 105 detects the level of a digital sound input DIN and outputs digital input level data DLV. A level control part 101 compares the digital input level data with analog input level data ALV and sets the level so that the ALV can be maximum in a range not to exceed the DLV. Thus, even at the time of the analog recording, the optimum recording level can be automatically set.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a recording level setting device that can be used in a device for recording digital data such as an R-DAT (rotating head type digital audio tape recorder).

Conventional technology In recent years, digital technology has been applied to many fields such as audio and imaging, and has been used in CD players, R-DATs, digital VTRs, etc.
Such technologies have been established. Among them, basic PCM
Along with signal recording and playback technology, technology that pursues ease of use, such as automatic recording level setting, has become important. Digital recording can have a wider dynamic range than analog recording, but if the recording level is not appropriate, the wide dynamic range cannot be fully utilized.

Of course, when digital input signals are directly recorded using a digital interface, it is not necessary to set the recording level, but direct recording of digital input signals may be prohibited for copyright protection reasons. Therefore, in conventional recording devices, the volume level of the music source to be recorded from the beginning to the end is checked, and the level is set so that the maximum value does not exceed the dynamic range of the recording device.

Problems to be Solved by the Invention However, with the above method, it is necessary to once play back the music source that you want to record from the beginning to the end, and the problem is that it takes twice the time to record the music source that you want to record. It had a point.

SUMMARY OF THE INVENTION The present invention is intended to solve the above-mentioned conventional problems, and an object of the present invention is to provide a level setting device that can automatically set an optimal recording level even during analog recording.

Means for Solving the Problems The level setting device of the present invention converts analog input signals into A/D converters.
an A/D converter to convert, a first level detection section that detects the level of digital data output from the A/D converter, a second level detection section that detects the level of the digital input signal, and the first level detection section that detects the level of the digital input signal; , the level control section controls the level of the analog input signal so that the relationship between the first and second level data output from the second level detection section satisfies a specific condition.

According to the above-described configuration, the present invention detects the digital level of the recording source from the digital signal line using the digital signal line and analog signal line on which the same signal is transmitted, and detects the digital level of the recording source after A/D conversion of the analog signal. By setting the level of the analog signal so that the digital level does not exceed the digital level of the recording source, the optimal recording level can be automatically set even during analog recording.

Embodiments Hereinafter, embodiments of the level setting device of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a level setting device according to the present invention. In FIG. 1, 1o1 is a level control section that controls the level of the analog voice input AIN. 102
is an A/D converter that converts the output signal of the level control section 101 into a digital signal. Reference numeral 103 denotes a recording unit that records digital data ADDAT output from the A/D converter 102. 104 is digital data ADD
Detects the AT level and receives analog input level data AL
This is a first level detection section that outputs V. 105 is a second level detection unit that detects the level of digital audio input DIN and outputs digital input level data DLV.

The level control section 101 receives digital input level data DL.
By comparing V and analog input level data AIV', A
The level coefficient K is set so that LY is maximized within a range that does not exceed DIJ. Note that the level of the output signal LAIH of the level control section 101 (') is a value obtained by multiplying the analog input level data ALY by the level coefficient K.

Next, the operation of the level control section 101 will be explained. Second
The figure is a flowchart showing the operation of the level control section 1o1. In Fig. 2, 201 is the initial value 1 for the level coefficient K.
This shows the process for setting the . 1 is a value sufficiently smaller than K. Reference numeral 202 indicates a process for determining the difference DEF between the digital input level data DLY and the analog input level data ALV. Reference numeral 203 indicates processing for determining whether DEF is smaller than a constant j.

If DEF is smaller than j, the level setting process ends and D
If EF is greater than or equal to J, the process of 204 is performed. 204 indicates a process of adding a constant S to the level coefficient K. After that, the process returns to step 202. Therefore, the level control section 101 gradually increases the level coefficient K, and ends the level setting process when the analog input level data A[, V become sufficiently close to the digital input level data DLY.

Effects of the Invention As described above, the level setting device of the present invention includes an A/D converter that converts an analog input signal into a digital signal, and an A/D converter that converts an analog input signal into a digital signal.
A first level detection section that detects the level of digital data output from the converter, a second level detection section that detects the level of the digital input signal, and Lm2 output from the first and second level detection sections. A digital signal line and an analog signal line that transmit the same signal are configured to include a level control unit that controls the level of the analog input signal so that the relationship between level data satisfies specific conditions. Detect the digital level of the recording source from the digital signal line using This allows the optimal recording level to be automatically set even during analog recording.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of the level setting device of the present invention, and FIG. 2 is a flow chart showing the operation of the level control section 101. 101- Level control section, 102 A/D converter, 103... Recording section, 104-
・ ・ 1st level detection section, 10.5... 2nd level detection section.

Claims (1)

[Claims] An A/D converter that A/D converts an analog input signal, a first level detector that detects the level of digital data output from the A/D converter, and a second level detector that detects the level of the digital input signal. A level control section is provided for controlling the level of the analog input signal so that the relationship between the detection section and the first and second level data output from the first and second level detection sections satisfies a specific condition. A level setting device featuring: