JP2001265399A - Voice file editing method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform the editing of voice files only by performing an editing operation while selecting files to be edited to automatically make a sampling frequency constant. SOLUTION: The editing of arbitrary voice files is performed with one operation by providing a means editing the voice files becoming necessary at the time of performing editing capable of being handled on a personal computer and a means making the sampling frequency becoming necessary at the time of performing the editing constant in this device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method and apparatus for editing an audio file, and more particularly to a method and apparatus for editing an edit file that can be handled on a personal computer.

[0002]

2. Description of the Related Art When editing digital audio files composed of a plurality of different sampling frequencies or mixing audio, it is necessary to keep the sampling frequency constant before editing. The sampling frequency conversion is performed by the method described in Japanese Unexamined Patent Publication No. Hei 5-235698. In this method, in order to determine a point to be subjected to linear interpolation, there are many preparatory steps such as 8-times oversampling and polynomial interpolation (Lagrange 7th-order interpolation) calculation, and a high processing speed is required.

After the sampling frequency is made constant, an editing process, for example, a process of audio mixing or audio combining is started.

[0004]

However, in the method of editing a plurality of audio files as described above, it is necessary to make the sampling frequency constant in advance. 1. Perform “sampling frequency stabilization”; Enter "edit" work. Must be performed in two steps. This not only increases the number of operations but also makes the user aware of the task of stabilizing the sampling frequency. In addition, the sampling frequency of each audio file to be edited must be checked using some method in order to determine at which sampling frequency the signal is to be fixed (hereinafter referred to as a decision). In such a situation, the user is required to have a corresponding skill and knowledge level, so that there is a problem that convenience is reduced.

The present invention has been made to solve these problems.

[0006]

According to a first aspect of the present invention, there is provided a step of designating and selecting an audio file to be edited from stored audio files, and a sampling frequency used for editing from the selected audio file to be edited. And converting the sampling frequency of the specified / selected audio file to be edited into the sampling frequency determined in the step.

A second invention is a means for storing a plurality of audio files having different sampling frequencies, a means for specifying and selecting an audio file to be edited from the plurality of audio files, Means for determining a sampling frequency to be used for editing from a target audio file, and means for converting each sampling frequency of the specified / selected audio file to be edited to the determined sampling frequency. Is an audio file editing device.

In a third aspect based on the first aspect, the sampling frequency determined from the designated / selected audio file to be edited is a sampling frequency of the designated / selected audio file to be edited. Is the maximum value of the audio file.

In a fourth aspect based on the first aspect, the sampling frequency determined from the specified / selected audio file to be edited is a sampling frequency of the specified / selected audio file to be edited. The audio file editing method is characterized in that it is an intermediate value of the audio file.

In a fifth aspect based on the first aspect, the sampling frequency determined from the specified / selected audio file to be edited is a sampling frequency of the specified / selected audio file to be edited. The audio file editing method is characterized by being a minimum value of

In a sixth aspect based on any one of the first or third to fifth aspects, the ratio of the sampling frequency of the designated / selected audio file to be edited to the sampling frequency used for editing is as follows. This audio file editing method has an integer multiple and a decimal multiple sampling frequency, and when the multiple is a decimal multiple, adds a decimal part and performs an interpolation process based on the added value.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an audio file editing method and apparatus according to the present invention will be described below with reference to FIGS.

FIG. 1 shows an example of the configuration of an embodiment of an audio file editing apparatus according to the present invention. The audio file 1 to be edited, an audio file input processing unit 2, a conversion sampling frequency automatic determination processing unit 3, a sampling frequency conversion unit It comprises a processing section 4, an editing processing section 5, an edited audio file storage section 6, and a conversion value determination table 7.

The operation will be described below based on an embodiment of the above configuration.

In FIG. 1, a user edits a plurality of files 1 (a, b, c, c,...) 1 having different sampling frequencies from audio files (not shown) stored in a personal computer or the like.
When the user specifies and selects d), the audio file input processing unit 2 reads all the audio files specified and selected.
Then, the conversion sampling frequency automatic determination processing unit 3 extracts sampling frequencies from all the audio files 1 to be edited, and determines at which sampling frequency in the read audio file the sampling frequency should be constant. The sampling frequency conversion processing unit 4 performs actual frequency conversion processing at the determined sampling frequency, and the editing processing unit 5 performs desired editing.

Next, a processing flow in the conversion sampling frequency automatic determination processing section 3 will be described with reference to FIGS.

FIG. 2 shows, as a processing flow, an example in which the largest frequency (maximum frequency) is adopted as the conversion value as the processing in the conversion sampling frequency automatic determination processing section 3.

In FIG. 2, first, the audio file 1 to be edited
The respective sampling frequencies are extracted from (step S1). In the sampling frequency extracted in the above step,
The largest frequency value is searched (S2). Then, the result is determined as the conversion frequency (S3).

For example, the audio sampling frequencies acquired from the audio file 1 to be edited are 8 kHz and 11.025 kHz, respectively.
z, 22.05kHz, 44.1kHz, the maximum frequency value is 4
Since the frequency is 4.1 kHz, the conversion frequency value is determined to be 44.1 kHz. Then, in the sampling frequency conversion processing unit 4 at the next stage, the sampling frequency of each audio file to be edited is converted to the maximum frequency of 44.1 kHz by, for example, a well-known upsampling conversion process.

Conversion sampling frequency automatic determination processing unit 3
The conversion value determined by (1) may be another value, and FIG. 3 illustrates, as a processing flow, an example in which an intermediate frequency is used as the conversion value as the processing in the conversion sampling frequency automatic determination processing unit 3.

In FIG. 3, an average value of the sampling frequency is calculated from the sampling frequency (S1) obtained from the audio file to be edited (S2). The average value and the conversion value determination table 7 that the application has in advance
A value closest to the average value is searched from among the sampling frequencies registered in (3). The result is determined as a converted value of the sampling frequency (S4).

A description will be given using a specific example. The sampling frequency of the audio file 1 to be edited is 8 kHz and 11.025 kHz, respectively.
z, 22.05kHz, 44.1kHz, and the conversion value determination table 7 has 8kHz, 11.025kHz, 16kHz, 22.050kHz, 32kHz, 44.1kHz.
It is assumed that the value of z is registered. At this time, the average value of the sampling frequency of the audio file 1 to be edited is 21.29375.
kHz. When a value closest to this 21.29375 kHz is searched from the conversion value determination table 7, it is 22.05 kHz, and this value is determined as a conversion value.

The obtained average value itself cannot be used as a sampling frequency. The table 7 is provided so that the obtained average value is approximated to one of the sampling frequencies of the audio file to be edited and used.

When the intermediate value of the audio file to be edited is determined as the sampling frequency, the sampling frequency conversion processing unit 4 performs the up-sampling conversion process on the audio file having the intermediate value or less, and the audio file having the intermediate value or more. The file is converted to an intermediate sampling frequency by a downsampling conversion process.

FIG. 4 shows, as a processing flow, an example in which the smallest frequency (minimum frequency) is adopted as the conversion value as the processing in the conversion sampling frequency automatic determination processing section 3. In FIG. 4, first, each sampling frequency is extracted from the audio file 1 to be edited (S
1). Find the smallest frequency value among them (S
2) The result is adopted as a conversion value (S3). As a specific example, the sampling frequency of the audio file 1 to be edited is 8kHz, 11.025kHz, 22.05kHz, 44.1kHz, respectively.
When z is set, the smallest frequency value is 8kHz
Therefore, the adopted frequency value is determined to be 8 kHz.

In this case, the sampling frequency conversion processing section 4 converts the sampling frequency of the audio file to be edited to the minimum frequency by downsampling conversion processing.

As described above, in the present embodiment, an audio file to be edited is designated and selected from the stored audio files, and a sampling frequency to be used for editing is determined from the selected audio file to be edited. Then, the sampling frequency of each of the specified / selected audio files to be edited is converted into the sampling frequency determined in the step. Therefore, as in the prior art, the two-step operation of performing “fixing the sampling frequency” in advance and then performing the “editing” work is not necessary, and the determination of the sampling frequency to be used for editing, and
Audio file editing can be performed by one operation.

Further, in the sampling frequency conversion processing section 4, the sampling frequency of the audio file to be edited and the sampling frequency used for editing have a sampling frequency whose ratio is an integral multiple and a decimal multiple. At this time, if the decimal part is added and the interpolation processing is performed based on the added value, it is possible to perform a low-load and high-speed multiple sampling frequency conversion, which is useful.

FIG. 5 shows a sampling frequency conversion processing unit 4.
The following describes an example of the upsampling conversion process performed in step (1). For example, when performing a conversion process from 11.025 kHz to 44.1 kHz, an interpolation value is determined such that the data is simply quadrupled, and an integer multiple conversion for inserting data is performed. However, in the case of conversion from 8 kHz to 44.1 kHz such as a decimal multiple (5.5125 times), basically, an integer multiple (5 times) conversion is performed, but a decimal part (0.5125 is equivalent in this example) is added. When it becomes 1 or more, the interpolation process is performed by adding 1 to the interpolation multiple. After this interpolation processing, subtract 1 from the added value,
The subsequent interpolation processing is repeated.

FIG. 6 shows a sampling frequency conversion processing unit 4.
1 illustrates the downsampling conversion process performed in step (a). In this case, the interpolation number referred to in the example of FIG. 5 may be considered as a thinning number, and realization is possible by thinning out the sample data by the thinning number.

As described above, by using the sampling frequency conversion of the integral multiple and the decimal multiple, it is possible to perform the low-load and high-speed sampling frequency conversion of the multiple.

[0032]

According to the present invention described above, the following effects can be obtained.

The audio file editing method and apparatus according to the first and second aspects of the present invention have the above-described configuration.
Editing of an arbitrary audio file can be performed by one operation.

Since the audio file editing method according to the third to fifth aspects has the above-described configuration, the sampling frequency used for editing can be selected to the frequency intended by the user or the designer, and the sampling frequency conversion can be performed. It has the advantage of being done automatically.

Since the audio file editing method according to the sixth aspect has the above-described configuration, it is possible to perform low-load and high-speed sampling frequency conversion of a decimal multiple.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a processing configuration of an audio file editing device according to the present invention.

FIG. 2 is a flowchart of an automatic determination process when a maximum value of a conversion sampling frequency is used according to the present invention.

FIG. 3 is a flowchart of an automatic determination process when using an average value of conversion sampling frequencies according to the present invention.

FIG. 4 is a flowchart of an automatic determination process when the minimum value of the conversion sampling frequency is used according to the present invention.

FIG. 5 is a diagram showing a method of upsampling frequency conversion at an arbitrary multiple according to the present invention;

FIG. 6 is a diagram illustrating a method of downsampling frequency conversion at an arbitrary magnification according to the present invention;

[Explanation of symbols]

 Reference Signs List 1 audio file to be edited 2 audio file input processing unit 3 conversion sampling frequency automatic determination processing unit 4 sampling frequency conversion processing unit 5 editing processing unit 6 editing result audio file 7 conversion value determination table

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5B082 GA02 5D045 BA02 9A001 BB03 BB06 EZ05 HH15 KK31 KK62 KZ43

Claims (6)

[Claims] A step of specifying and selecting an audio file to be edited from the stored audio files; a step of determining a sampling frequency to be used for editing from the selected audio file to be edited; Converting the sampling frequency of each of the edited audio files into the sampling frequency determined in the step. 2. A means for storing a plurality of audio files having different sampling frequencies, a means for specifying and selecting an audio file to be edited from the plurality of audio files, and a voice to be edited which is specified and selected. Means for determining a sampling frequency to be used for editing from a file; and means for converting a sampling frequency of each of the specified / selected audio files to be edited to the determined sampling frequency. Audio file editing device. 3. The sampling frequency determined from the specified / selected audio file to be edited is a maximum value of the sampling frequency of the specified / selected audio file to be edited. Claim 1
Audio file editing method described in. 4. The sampling frequency determined from the specified / selected audio file to be edited is an intermediate value of the sampling frequency of the specified / selected audio file to be edited. Claim 1
Audio file editing method described in. 5. The sampling frequency determined from the specified / selected audio file to be edited is a minimum value of the sampling frequency of the specified / selected audio file to be edited. Claim 1
Audio file editing method described in. Claim 1 characterized by the following:
How to edit audio files. 6. The sampling frequency of the specified and selected audio file to be edited and the sampling frequency used for editing have a sampling frequency of an integer multiple and a decimal multiple. 6. The audio file editing method according to claim 1, wherein a decimal part is added and interpolation processing is performed based on the added value.