JP2000348473A - Audio recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make realizable a cross-fade processing for patching the voices before and after a patch recording area through overlap of several seconds without the post-edition on the occasion of executing a patch recording in an audio recording apparatus. SOLUTION: This audio recording apparatus is provided with a main audio data recording means 20, an auxiliary audio data recording means 30 for holding the audio data stored immediately after recording/temporary stop operation up to the restart of the next recording, and a means for executing the cross-fade process for recording the audio data through the fade-in and fade-out while the audio data before and after the position where the recording is started again after the temporary stop, namely the patching position, are overlapped with each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a video recorder,
The present invention relates to a sound recording device such as an audio recorder.

[0002]

2. Description of the Related Art In a video recorder and an audio recorder, after recording a sound or the like, the recording is paused, and another sound is recorded again after the already recorded sound.
The recording is being performed. In these existing video recorders and audio recorders, regardless of whether they are for business use or for consumer use, the sound is slowly faded out and faded in for a few seconds (for example, about 5 seconds) before and after the connecting portion. Some have functions.

[0003] However, even with similar faders, the crossfade function of overlapping the sound before and after the joint portion is installed only in recorders for business and broadcast stations, and professional editing equipment used in music production sites and the like. It has not been. One of the reasons is that a complicated post-editing operation is required after recording in order to perform a crossfade, so that it cannot be mounted on a consumer device by the same method.

However, the cross-fade function is a useful function for consumer devices because it provides an easy-to-understand and fun effect. Therefore, it is desired to develop a device equipped with a crossfade function that is easy to operate for general home use.

As one method of realizing the cross-fade function, a data reading device and a data writing device from a medium, for example, when the medium is a tape, a so-called reproducing head and a recording head are arranged in this order in the recording direction. In this method, while reading the base data already recorded by the preceding head, a new input audio signal is mixed with the data and overwritten by the succeeding head. -128955). However, this method has the disadvantage that the number of required heads increases. At present, the advancement of semiconductor technology and the availability of inexpensive digital signal processing circuits have led to an increase in the number of heads compared to an increase in digital signal processing circuits. It is disadvantageous from the viewpoint of realizing it at low cost. Also, it is very difficult to implement this method within existing audio (video) recording formats.

As another method, in the case of an audio recording apparatus that performs recording by a helical scan method using a rotating head, a time zone in which two heads disposed on the head drum simultaneously operate on the tape (the same signal is transmitted for two times). A method of realizing cross-fade by utilizing the fact that there is a time zone in which two heads record in duplicate (for this, refer to Japanese Patent Application No. 59-1).
98533), but in this case the overlap time is negligible. The crossfade time to be realized by the present invention is several seconds (for example, 5 seconds).
Second), which cannot be realized by this method.

[0007] Further, in current consumer camera-integrated video, image overlap fader is widely implemented (however, in a currently used apparatus, an image of a connecting portion is a still image). If the sound can be cross-fade in accordance with it, it will be possible to produce a very effective effect at the time of a scene change, but at present, such overlap fader processing of both image and sound can be done immediately without post-editing A camera-integrated video or the like to be realized has not been put to practical use.

[0008]

SUMMARY OF THE INVENTION The present invention realizes an easy-to-operate and effective audio crossfade suitable mainly for a home camera integrated video, a video deck, and various other home digital / analog audio recorders. The task is to

[0009]

In order to solve the above-mentioned problems, the present invention provides an audio recording device having the following means. That is, according to one aspect of the present invention, main audio data recording means, auxiliary audio data recording means for holding audio data stored immediately after the recording / pausing operation until the next recording restart, and temporarily stopping recording Means for performing a cross-fade process of recording as a fade-in / fade-out while overlapping the sound before and after the part restarted after the processing, that is, the connection part, while overlapping each other.

According to another aspect of the present invention, in the first audio recording device, when the continuous recording is restarted, the immediately preceding audio data recorded in the main audio data recording means is played back to assist. The present invention provides an audio recording device provided with a means for re-storing in a dynamic audio data recording means.

[0011] According to still another aspect of the present invention, the above first aspect is provided.
The auxiliary data recording means is not fixedly mounted on the main body of the audio recording device, but is provided by a removable semiconductor memory. According to still another aspect of the present invention, in the first audio recording device, a cassette for a DV video cassette recorder is used as the main audio data recording means, and the cassette is used as the auxiliary audio data recording means. The present invention provides an audio recording device that performs a cross-fade process using a cassette memory built in the audio recording device.

According to still another aspect of the present invention, the first aspect
In the above-mentioned audio recording apparatus, audio data recording means capable of recording on each track of a recording medium having more audio recording tracks than the number of input audio channels to be recorded is prepared, and the surplus audio recording tracks are cross-fade processed. The present invention provides an audio recording device that performs cross-fade processing at a connection point, using the auxiliary audio recording area as an auxiliary audio recording area.

According to still another aspect of the present invention, the first aspect
In the audio recording apparatus, a DV video cassette recorder or a digital eight video cassette recorder is used, and the 4ch channel defined by the audio recording format is used.
Using the audio mode, the recording area of two channels among them is used for main audio recording, and the remaining two channels are used as auxiliary audio recording areas for crossfading, and cross-fade processing is performed at a connection point. The present invention provides a sound recording device adapted to perform the following.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Various embodiments of the audio recording apparatus according to the present invention will be described below. Prior to that, first, a brief description will be given of crossfading. FIG.
(A) shows the operating characteristics of the fader at the point where a conventional home camera-integrated video is spliced. As shown, a recorder of this type is intended to smoothly reduce the volume and then increase the volume slowly so that the sound is perceived smoothly at the transition between scenes. The fade-out / fade-in time is usually set to the number of seconds (several 100 msec to about 5 sec) in many cases.

FIG. 7B shows the operating characteristics of the cross fade. As shown in this figure, in this method, the sound before and after the joint shooting point is overlapped. By doing so, it is possible to more effectively produce a scene change. At this time, the recording pause point must be at the point indicated by the dotted line in the figure, and this processing cannot be realized unless the audio data immediately before the end of the previous scene is stored in some way until the recording is restarted.

The audio recording apparatus of the present invention has been studied for storing the above audio data, and will be described in detail below. FIG. 1 shows a circuit of the audio recording device according to the first embodiment of the present invention. Here, the auxiliary audio data recording means 30
Even with the storage capacity to record audio data for the time required for crossfading, at least the input / output speed to record and reproduce audio data in real time, and the function to change the reading position instantly so that it can be ignored in terms of hearing If so, analog recording means or digital recording means may be used. However, here, a case will be described in which the auxiliary audio data recording means is a RAM and the audio data to be handled are all digital signals.

In FIG. 1, signal level attenuators 40 and 50 and an adder 60 are a group of circuits for mixing signals necessary for a crossfader operation. The input sound 10 to be recorded is normally recorded in the main sound data recording means via the signal level attenuator 40 and the adder 60 during normal operation (when the crossfade is not operating), and is also recorded in the auxiliary sound data recording means 30. Recorded at the same time. Attenuation coefficient (multiplication coefficient) α given to signal level attenuators 40 and 50
Is generated by the crossfader control unit 80. Normally, the attenuation coefficient α is set to 1. That is, since α = 1 is given to the signal level attenuator 40 and 1−α = 0 is given to the signal level attenuator 40, only the input voice 10 is recorded in the main voice data recording means 20 at 100%. Become.

On the other hand, during the cross-fade operation, the auxiliary audio data recording means 30 does not perform the data input operation, but only performs the output operation of the already recorded data in the normal state.
The crossfader control unit 80 sets the attenuation coefficient α to 0 ≦ α ≦
It is changed continuously within the range of 1. Then, the input voice 10
Is multiplied by α in the signal level attenuator 40 and data obtained by multiplying the output from the auxiliary audio data recording means 30 by (1−α) in the signal level attenuator 50 are added in the adder 60. The signals are recorded in the main audio data recording means 20, and thus a necessary signal mix at the time of the crossfader operation is realized.

The command signal 70 is a signal for giving an operation command to the entire sound recording apparatus, and represents a command such as "record" or "stop". The crossfader control unit 80 operates on the basis of a command signal 70 given from the outside, and an operation mode signal 120 for controlling the operation of the main audio data recording means 20.
Is generated and supplied to the auxiliary audio data recording means 30 (RAM). The address signal 90 (ADS) and the write enable flag 100 (RW, where 1 is write enable, 0 is write disable) And a signal level attenuator 40
, And 50 are generated. The crossfader control unit 80 has a register 110 for holding one address value therein.

In the circuit of FIG. 1, in order to briefly explain the principle of operation, the path until the input voice 10 is recorded in the main voice data recording means 20 and the auxiliary voice data recording means 30 and the auxiliary voice In the following description, it is assumed that there is no circuit with a time delay of the data on the path until the output data from the data recording means 30 is recorded on the main audio data recording means 20.

FIG. 2 shows an example of a timing chart of the cross-fade processing operation of the circuit of FIG. There are various ways to control the RAM, but the simplest method is described here. First, the timing when transitioning from the recording state to the stop state will be described. The crossfader controller 80 keeps increasing the address signal 90 one by one at the data input rate. Then, after the address signal 90 reaches the last address value of the RAM, it returns to the first address value and repeats the address increase.
That is, for example, [1 data length: 16 bits] × [number of recorded data: 240000 data] = [3.84 Mbits]
In the case of using the RAM of FIG.
2, 239999, 239999, 0, 1, 2, ‥
Change as ‥.

During this time, the RAM write permission flag 100 is set to 1
Keep it. The attenuation coefficient α is always set to 1 during normal recording. By doing so, the input data which is always retroactive from the present time by the amount of the RAM capacity is continuously stored in the RAM.

When the command signal 70 changes from "record" to "stop" by an external operation, the crossfader control unit 80 sets the main audio data recording means 20 to the "stop" mode, and simultaneously sets the address signal at that time. The value of 90 is stored in the address value holding register 110, and the write permission flag 100 is changed from 1 to 0 after a lapse of time necessary for crossfading therefrom. In this way, the input audio data after the main audio data recording unit is in the stop mode is stored in the RAM for the time required for the crossfade processing later.

Next, the timing when recording is restarted from the stop state will be described. Command signal 7 from external operation
When 0 changes from stop to recording, the crossfader control unit 80 sets the operation mode of the main audio data recording unit 20 to the recording mode, and presets the address signal 90 to a value stored in the address value holding register 110. Thereafter, the address value is increased by one as before. The crossfader control unit 80 further resets the attenuation coefficient α to zero at the same time when the address value is preset, and gradually increases the value of α over a desired crossfade time. When the value of α reaches 1, the write enable flag 1 is prepared for the magnetic field cross-fade processing.
00 is changed from 0 to 1 again.

If the above processing is performed, the sound stored immediately after the recording pause operation output from the RAM is multiplied by (1-α) by the signal level attenuator 50, and the input sound signal after the recording is resumed. 10 is multiplied by α in the signal level attenuator 40, and the two are added in the adder 60 and recorded in the main recording audio data recording means 20. At this time, if α is changed from 0 to 1, the desired value is obtained. Crossfade processing is realized.

In the above description, the case where the operation procedure is changed in the order of recording->stop-> recording has been described. However, in the audio recording apparatus of the first embodiment, the main audio data recording unit 20 is provided after the recording is temporarily stopped. When the recording position in the recording medium has been moved, that is, for example, when the main audio data recording means is a magnetic tape and the operation of fast-forwarding / rewinding the tape is performed, the data stored in the RAM is stored. The audio data and the current recording position of the main audio data recording means 20 cannot be correlated, causing a problem. But,
This inconvenience is solved if the main audio data recording means 20 has a function of accurately finding the last recording position of the previous time later. In this case, the operation state transition of the main audio data recording means 20 does not become as shown in FIG.
> Arbitrary operation (other than recording)-> jump to last last recording position-> recording, but the timing chart showing this situation is omitted. Further, the specific content of the method of finding the final recording position is not directly related to the present invention, so that the description thereof is also omitted.

Next, a second embodiment of the present invention will be described. In the first embodiment of the present invention, even if the audio recording device has the cueing function and can detect the last recording position of the previous time, the main audio data recording unit 20 can be used.
If the recording medium used in the above is a replaceable medium such as a cassette tape, the crossfade processing becomes impossible if the cassette is replaced. Also,
If a volatile RAM is used as the auxiliary audio data recording means, once the device is turned off, the RAM
The cross-fade processing becomes impossible because the stored contents of the data disappear.

On the other hand, in the second embodiment, when recording is resumed from the connection point, the main audio data recorded immediately before is temporarily played back and stored in the auxiliary audio data recording means. The above problem is solved by performing the crossfade processing after that.

FIG. 3 shows an example of a circuit of the audio recording apparatus according to the present embodiment. Again, the auxiliary audio data recording means 2
It is assumed that the RAM is used as 0, and the audio data to be handled is all digital signals. The difference from the first embodiment is that, in the second embodiment, the data input path to the auxiliary audio data recording means 30 is taken from the reproduction output section of the main audio data recording means 20.

FIG. 4 shows an example of the operation of the audio recording apparatus according to the second embodiment of the present invention shown in FIG. FIG.
It is a timing chart at the time of changing a command in order of>pause-> recording. It should be noted that the device of the second embodiment is different from the device of the first embodiment in that if audio has already been recorded in the main audio data recording means 20, the splicing by crossfade can be performed from any of the recorded locations. It can be carried out. In that case, the transition of recording-> stop illustrated in FIG. 4 is unnecessary.

The address signal 90 supplied to the RAM of the auxiliary audio data recording means 30 is always increased by 1 as in the previous case. When the command signal 70 changes from “record” to “stop” by an external operation, the crossfader control device 80 stops the main audio data recording unit 20. Next, when the command signal 70 changes from “stop” to “record”, the crossfader control unit 80 determines the write / read position on the recording medium in the main audio data recording means 20 in advance necessary for crossfading. (For tape media, rewind), and then read (reproduce) data.

At the retreat position, the write enable flag 100 of the RAM is set to 1, and the address signal 90 at that time is stored in the address holding register 110. In this way, the data transfer from the main audio data recording means 20 to the auxiliary audio data recording means 30 is performed, and when the read position from the main audio data recording means returns to the original position (the position where it was first stopped), the data is transferred to the RAM. Is set to zero. The write / read position of the main audio data recording means 20 is moved backward again by the time required for the above-mentioned predetermined crossfade. Then, the read address 90 from the RAM is preset to the value stored in the address holding register 110, the attenuation coefficient α is set to zero, the main audio data recording unit 20 is set to the recording mode, and the main audio data recording unit 20 is slowly set over the cross-fade time. And α are increased to 1.

By performing the above processing, the audio data immediately before the previous recording stop position stored in the auxiliary audio data recording means 30 and the input data are cross-fade and recorded in the main audio data recording means 20. Thus, the desired cross-fade processing can be realized. Since this method can be realized without any limitation on the recording start position of the main audio data recording means 20 (can be executed from any recorded position), the disadvantage of the above-described audio recording device of the first embodiment (the auxiliary audio After the data has been recorded in the data recording means, the write / read position of the main audio data recording means must not be moved).

Next, a third embodiment of the present invention will be described. As the auxiliary audio data recording means described in the first and second embodiments, the audio recording device of the third embodiment uses a removable nonvolatile semiconductor memory (portable IC recording medium). Such an external IC
An audio (video) recording / reproducing apparatus equipped with an interface with a recording medium and exchanging data is more and more likely to be used in the future. Since it can also be used as a part of the crossfader control unit 80 and a peripheral circuit of the auxiliary audio data recording means 30, there is an advantage that the circuit scale can be reduced.

Further, since the price of the semiconductor memory cannot be ignored, from the viewpoint of the user, it is possible to take the form that only the user who wants to use the crossfade function prepares the external IC medium. For users who do not need this function, there is an advantage that costs can be reduced. In addition, since the external IC medium is used in the method of the above-described first embodiment because it is nonvolatile, there is an advantage that no trouble occurs even after the power is once turned off.

Next, a fourth embodiment of the present invention will be described. In particular, when the present invention is applied to a DV video cassette recorder, a cassette memory (non-volatile semiconductor memory) provided as an option inside a DV (digital video) cassette is used as auxiliary audio data recording means. In this case, when the cassette is replaced, the correspondence between the data stored in the RAM and the main audio data is lost, which is a drawback of the above-described audio recording device of the first embodiment. The disadvantage that processing cannot be performed can be overcome.

Next, a fifth embodiment of the present invention will be described. This method eliminates the auxiliary audio data recording means, prepares a recording medium having a number of audio recording tracks larger than the number of channels required for recording the input audio, and prepares audio data recording means for those tracks, and provides the surplus audio data. The cross-fade processing is realized by using a recording track.

In the apparatus shown in FIG. 5, as an example, a circuit example in which the input audio to be recorded is one channel (monaural) and the audio data recording means is two channels (CH-1 and CH-2) is shown. I have. Here again, in order to simplify the explanation of the principle of operation, the path until the input audio 10 is recorded on CH-1 and CH-2 of the audio data recording means 20 and the reproduction of CH-2 by the main audio data recording means 20 It is assumed that there is no circuit with a time delay of data on any path until output data is recorded on CH-1.

The operation of the voice recording device shown in FIG. 5 is shown in FIG. FIG. 6 shows, as an example, a timing chart in the case where commands are transited in the order of recording->pause-> recording. Note that, similarly to the device according to the second embodiment, if the sound has already been recorded in the audio data recording means, the device according to the fifth embodiment of the present invention uses crossfade from any of the recorded locations. You can take a splice. In that case, the processing of the left half of FIG. 6 (left from the broken line) is unnecessary. However, in this case, as will be described later, a CH-channel is provided at least from the point where the splicing shooting is to be performed to a position temporally behind by a desired crossfade time.
It is necessary that the same sound is recorded in both 1 and CH-2.

First, in the steady state, the attenuation coefficient α is always set to 1 and the input voice 10 is
H-1 and CH-2 are recorded simultaneously.
When the command signal 70 changes from “recording” to “stop” by an operation from the outside, after continuing the recording for at least a desired cross-fade time, the write position is moved backward to the position where the command transitions ( In the case of tape media, rewind and stop.

Thereafter, when the command signal changes from "stop" to "record" again, the operation mode of the main audio data recording means 20 is changed to the write state for CH-1 and to the read state for CH-2, and at the same time, the attenuation coefficient is changed. α is set to 0, and then slowly set to 1 over a desired crossfade time.
By doing so, the command is "recorded" on the CH-2 side.
After the transition from "to" to "stop", the cross-fade processing of recording the extra audio data and the current audio input data on the CH-1 side can be realized. After α has reached 1, the operation mode of the audio data recording means is again set to the write mode for both CH-1 and CH-2 in preparation for the next crossfade processing.

According to this method, it is not necessary to separately provide auxiliary audio data recording means, and a control circuit for the auxiliary audio data recording means is not required, so that a circuit to be added is greatly simplified. Also, the first
The disadvantage of the audio recording device according to the embodiment, that the cross-fade processing cannot be performed when the recording position is moved to an arbitrary position or the recording medium is changed (for example, when the cassette is replaced), is overcome, and The burden of controlling the main audio data recording means is reduced as compared with the audio recording device of the second embodiment.

Finally, a sixth embodiment of the present invention will be described. In particular, in the audio recording using a DV video cassette recorder or a digital eight video cassette recorder, the 4ch-audio mode defined by each recording format is applied by applying the apparatus of the fifth embodiment. To use. If a DV system or a digital eight system video system having independent recording / reproducing means for four channels is used, crossfade processing can be realized with a relatively small number of additional circuits.

[0044]

According to the audio recording apparatus of the present invention, when performing the continuous recording, the cross-fade processing for overlapping and connecting the sound before and after the connected portion for several seconds can be performed without the need for post-editing. This can be realized instantly by simply performing the switching operation. Since cross-fade processing that can provide easy-to-understand and fun effect can be realized by simple operation, it is mainly used for home camera integrated video,
It is suitable for video decks and various other home digital / analog audio recorders. Particularly for video cameras and VCRs, extremely effective effects can be achieved by using them together with an image overlap fader.

[Brief description of the drawings]

FIG. 1 is a system block diagram of a crossfade processing device according to a first embodiment of the present invention.

FIG. 2 is an operation timing chart of the device of FIG. 1;

FIG. 3 is a system block diagram of a crossfade processing device according to a second embodiment of the present invention.

FIG. 4 is an operation timing chart of the device of FIG. 3;

FIG. 5 is a system block diagram of a crossfade processing device according to a fifth embodiment of the present invention.

6 is an operation timing chart of the device of FIG.

FIG. 7 is an explanatory diagram of a fade-in / fade-out operation.

[Explanation of symbols]

20 ‥‥ main audio data recording means, 30 ‥‥ auxiliary audio data recording means, 40, 50 ‥‥ signal level attenuator, 80 ‥
‥ Crossfader control section

Claims (6)

[Claims] 1. A main audio data recording means, an auxiliary audio data recording means for holding audio data stored immediately after a recording / pausing operation until the next recording restart, a place where recording is temporarily stopped and then resumed, That is, a means for performing a cross-fade process for recording the sound before and after the connection point, before and after the sound while overlapping and fading in and out. 2. The apparatus according to claim 1, wherein at the time of resuming the continuous recording, the immediately preceding audio data recorded in said main audio data recording means is played back and stored in the auxiliary audio data recording means again. An audio recording device provided with a means for resetting. 3. The audio recording device according to claim 1, wherein the auxiliary data recording means is not fixedly provided in the main body of the audio recording device, but is a removable semiconductor memory. 4. The apparatus according to claim 1, wherein a cassette for a DV video cassette recorder is used as said main audio data recording means, and a cassette memory built in said cassette is used as said auxiliary audio data recording means. An audio recording device that performs a cross-fade process using a. 5. The apparatus according to claim 1, further comprising audio data recording means for recording on each track of a recording medium having an audio recording track larger than the number of input audio channels to be recorded. An audio recording device that uses an existing audio recording track as an auxiliary audio recording area for cross-fade processing, and performs cross-fade processing at a connection point. 6. The apparatus according to claim 1, wherein a DV video cassette recorder or a digital eight video cassette recorder is used, and a 4ch-audio mode defined by an audio recording format is used.
An audio recording apparatus in which a recording area for two channels among them is used for main audio recording, and a remaining two channels are used as auxiliary audio recording areas for cross-fade, and cross-fade processing is performed at a connection point. .