JP2007157245A - Audio data recording/reproducing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a audio data recording/reproducing device capable of recording/reproducing audio data in a unified format. <P>SOLUTION: The audio data recording/reproducing device capable of recording and reproducing audio data comprises a format setting means of setting the audio data to a specified format, an audio data recording medium 10 where the audio data set by the format setting means are recorded, and a CPU 1 which controls operations of the whole. Consequently, the audio data can be handled in a standardized manner. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an audio data recording / reproducing apparatus.

  In broadcasting stations, professional (professional) audio data recording / reproducing devices are used. In recent years, digital audio data recording / reproducing devices have been used in place of analog audio data recording / reproducing devices. However, the data structure of the audio data recording / reproducing apparatus is an original format for each manufacturer, and there is no unified format. Further, there is no format that can be efficiently recorded / reproduced in an optical medium such as a DVD medium that requires a relatively long time for seeking. Therefore, there is no conventional technique corresponding to the present invention.

  As described above, the data structure of the audio data recording / reproducing apparatus is a format unique to each manufacturer and is not compatible with each manufacturer. In recent years, a data format called BWF (Broadcast Wave Format) has been proposed as a common format. This BWF is defined in “Tech 3285” of EBU. This format is a combination of a plurality of minimum unit chunks called chunks. However, the current situation is that the size and order of chunks differ among manufacturers, and complete compatibility is not achieved.

Further, the format structure so far is not optimal for optical media such as DVD, and the efficiency has deteriorated during recording, reproduction and editing.
The present invention has been made in view of such problems, and provides an audio data recording / reproducing apparatus capable of efficiently recording / reproducing audio data in a unified format on a DVD medium. The purpose is that.

(1) According to the first aspect of the present invention, in an audio data recording / reproducing apparatus capable of recording and reproducing audio data, format setting means for setting the audio data in a predetermined format, and setting by the format setting means And an audio data recording medium for recording the audio data and a CPU for controlling the overall operation.
(2) In the invention according to claim 2, the audio data format is composed of a RIFF header, a META data area, and an AUDIO data area, and the META data area has a fixed length and records predetermined information. When the size of the region varies, the remaining region is a variable-length PAD region.

Here, RIFF is defined in “Multimedia Programming Interface Specification 1.0” by IBM and Microsoft.
(3) In the invention according to claim 3, the META data area has a fixed length, and when the size of the area for recording predetermined information varies, the remaining area is set as a variable length PAD area. As the audio data recording medium, DVD media can be handled efficiently.

(1) According to the first aspect of the invention, it is possible to record and reproduce audio data according to a unified format.
(2) According to the second aspect of the present invention, the META data area has a fixed length, and even if the amount of META data increases or decreases, the remaining area is made up of dummy data called PAD so that the audio data Can be handled in a unified manner, and BWF can be handled efficiently.
(3) According to the invention described in claim 3, by using the DVD medium as the audio data recording medium, it is possible to simplify the mounting and taking out of the apparatus, and the operability can be improved.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of the present invention. In the figure, 1 is a CPU for controlling the operation of the entire apparatus, and 2 is a timing clock generator for giving a timing clock to the CPU 1. Reference numeral 3 denotes an operation unit for operating the apparatus, which includes various knobs and switches. Reference numeral 4 denotes a display unit that displays various types of information associated with recording / reproduction of audio data. The display unit 4 includes, for example, a level display unit, a clock display unit, a time display unit, various operation information display units, and the like.

  Reference numeral 5 denotes a flash (FLASH) -ROM in which an operation program is recorded, and reference numeral 6 denotes an SD-RAM used as a buffer at the time of program execution and data recording / reproduction. Reference numeral 7 denotes an A / D converter that receives analog input and converts it into digital data. Reference numeral 8 denotes a D / A converter that converts digital audio data into an analog audio signal and outputs the analog audio signal. A timing clock is input from the timing clock generator 2 to the A / D converter 7 and the D / A converter 8. As these A / D converter 7 and D / A converter 8, a plurality of channels can be used. For example, 8 channels can be used. As a method of the A / D converter 7 and the D / A converter 8, for example, a Σ / Δ modulation method is used. A serial / parallel (S / P) converter 9 performs mutual conversion between serial data and parallel data.

  Reference numeral 10 denotes a DVD medium as an audio data recording medium for writing (recording) and reading (reproducing) audio data, and 11 is a hard disk (HDD) for writing and reading audio data. Here, by using a DVD medium as the audio data recording medium, it is possible to easily attach and remove the apparatus to and from the apparatus, and to improve operability. As the DVD medium, for example, a DVD-RAM is used, and for example, a standard type of 12 cm is used. The HDD is not necessarily required, and is provided as necessary. Reference numeral 12 denotes a computer connected to the DVD medium 10, which is a computer that writes data to and reads data from the DVD medium 10. As the computer 12, for example, a personal computer or the like is used. The DVD medium 10 and the computer 12 are connected via a USB interface described later.

  Here, two types of positioning of the computer 12 are assumed. One is to directly connect to the recorder via USB or ETHERNET (registered trademark of Fuji Xerox Co., Ltd.), and the other is to take advantage of removable media and load the DVD media into the computer drive. This is a method for exchanging files.

Reference numeral 13 denotes a CPU 1, operation unit 3, FLASH-ROM 5, SD-RAM 6, S / P converter 9, DVD medium 10, HDD 11, a common bus (BUS 1), and 14 an S / P converter 9 and A This is a serial signal line connecting the / D converter 7 and the D / A converter 8. Reference numeral 15 denotes a USB interface connected between the computer 12 and BUS1. A USB interface 15 connects the computer 12 and the BUS1. The operation of the apparatus configured as described above will be described below.
(When writing audio data)
The DVD medium 10 is mounted on the mounting unit. Usually, since the tray comes out of the apparatus main body, the DVD medium is set in the mounting portion. Once set, the DVD medium 10 is drawn into the apparatus. In this state, the operation unit 3 is operated to start the operation of the apparatus. First, an analog audio signal is input. Analog audio may be input directly from a microphone or input from another audio device. The input analog audio signal is converted into digital audio data by the A / D converter 7. This digital audio data enters the subsequent S / P converter 9 and is converted into parallel audio data.

  The CPU 1 performs predetermined processing, for example, formatting processing as shown in FIG. 2, on the digital audio data as necessary. In this processing, the SD-RAM 6 is used as necessary for primary data recording. The CPU 1 receives the output of the timing clock generator 2 that determines the operation timing. The audio data sampled by the signal from the timing clock generator 2 is added to other data (for example, the RIFF header and META data). ) Is added by the CPU 1 and written to the DVD medium 10.

In this case, when the number of channels to be written is a plurality of channels, audio data is written for each channel. Alternatively, output audio data from the computer 12 may be written as necessary. It is also written in the HDD 11. The DVD medium 10 in which the audio data is written is read out and reproduced as necessary, or is written into the computer 12 via the USB interface 15. Or it is reproduced by another audio device.
(During audio data playback)
The DVD medium 10 in which the audio data is written is set in the apparatus. Then, playback is started from the operation unit 3. When the CPU 1 detects this reproduction start, it accesses the DVD medium 10 and reads the audio data. In this case, since the audio data file has a unified format as will be described later, and the data up to the audio data is fixed-length data, the data can be efficiently sought. The read audio data is converted into serial data by the S / P converter 9, and then converted into an analog audio signal by the subsequent D / A converter 8, and output as an audio signal. The output audio signal is amplified by, for example, a power amplifier, and is input to a speaker and can be heard as audio.
(Audio data format)
Next, the audio data file format used in the present invention will be described. FIG. 2 shows the structure of the file. As shown in the figure, it is composed of a Resource Interchange File Format (RIFF) header, a META data area, and an AUDIO data area. The RIFF header includes “RIFF”, a file length (file-length), and “WAVE”. The AUDIO data area is called a data chunk, and is composed of “data”, chunk length (ck-size), and chunk data (AUDIO data). “ck” is an abbreviation for chunk. Here, the area from the beginning of the file to the chunk data of the data chunk is assumed to be 32 × n (n is an integer of 1 or more) bytes, which is the physical minimum writing unit of the DVD medium.

  FIG. 3 is a diagram showing an example of the META (meta) data format. As shown in the figure, it is composed of broadcast_audio_extension-ck, fmt-ck, cue-point-ck, playlist-ck, associated-data-ck, iXML-ck, other-ck, and PAD-ck. Here, iXML is defined in “iXML Specification Revision 1.41” (http://www.ixml.info/). PAD-ck is a variable length area, and the META data area has a fixed length. Here, the data area recorded in the META data area is composed of an arbitrary number of data. Therefore, the data length of each data is variable depending on the number of data recorded in the META data area. Although the META data length is fixed, the combined data length is variable, so this fluctuation is absorbed by PAD-ck.

  That is, since the META data area as a whole is fixed, the variable portion is absorbed by the PAD-ck by changing each data length. PAD-ck contains dummy data. By changing the dummy data area, the condition that the META data has a fixed length is satisfied.

  As described above, according to the present invention, audio data can be efficiently recorded and reproduced according to a unified format. In addition, by managing in units of 32 k × n bytes that are well-divided for DVD media, even for media that cannot be directly overwritten, such as DVD-R, the area of 32 k × n bytes is rewritten to a new area, and the DVD file system By changing the link information managed by UDF (Universal Disc Format), the META data can be changed without affecting the audio data area (see FIG. 6).

  Regarding CUE chunks, whether a certain amount of area is secured, and the CUE chunks that are not registered are registered by setting the upper 8 bits of number_of_cue (which will not be used practically) to ffH Be able to judge whether or not As a result, editing such as registration or deletion of cue chunks does not change the overall length of the file or the META data area length, and it becomes possible to edit cue relatively easily.

  FIG. 4 is a diagram showing a format example of audio (AUDIO) data. In the header portion, ck-id = “DATA” is entered, then ck-size is entered, and then data for n channels is entered. The data for n channels is composed of Channel 1, Channel 2, and Channel n, and becomes sample 1 in the following manner, and thereafter, audio data enters sample 2 and sample 3 in the same manner. The data length of the audio data is variable depending on the audio length.

FIG. 5 is a diagram illustrating a format example of a chunk (ck). As shown in the figure, it consists of ck-id, ck-size, and ck data.
Hereinafter, each data area in FIG. 3 will be described. The cue-point chunk indicates a position in the WAVE data, and is also used as a position of a playlist chunk described later. The playlist chunk is used for sequential playback depending on the cue-point specified in the playlist playback mode. The associated-data chunk is a chunk that adds related information to the cue-point registered in the cue-point chunk. If a label chunk is used, an easy-to-understand name can be added to each cue-point. . The iXML chunk is a chunk that records BWF META data information. The other chunk is a chunk added as necessary. As described above, the pad chunk is dummy data used to absorb a change in the data length due to a change in META data and make it a fixed length.

  As described above in detail, according to the present invention, an audio data recording / reproducing apparatus that can handle audio data in a unified manner and can efficiently process audio data based on a new idea is realized. be able to.

It is a block diagram which shows one embodiment of this invention. It is a figure which shows the structure of a file. It is a figure which shows the example of a format of metadata. It is a figure which shows the example of a format of audio data. It is a figure which shows the format example of a chunk. It is explanatory drawing of the link change of metadata.

Explanation of symbols

1 CPU
2 Timing clock generator 3 Operation unit 4 Polling processing unit 5 FLASH ROM
6 SD-RAM
7 A / D converter 8 D / A converter 9 S / P converter 10 DVD media 11 HDD
12 Computer 13 BUS1
14 Serial signal line 15 USB interface

Claims (3)

In an audio data recording / reproducing apparatus capable of recording and reproducing audio data,
Format setting means for setting audio data to a predetermined format;
An audio data recording medium for recording audio data set by the format setting means;
A CPU that controls the overall operation;
An audio data recording / reproducing apparatus configured to include:   The audio data format is composed of a RIFF header, a META data area, and an AUDIO data area. The META data area has a fixed length, and when the size of an area for recording predetermined information varies, 2. The audio data recording / reproducing apparatus according to claim 1, wherein the area is a variable length PAD area.   The META data area has a fixed length. When the size of an area for recording predetermined information varies, the remaining area is a variable-length PAD area, so that the DVD medium can be efficiently used as the audio data recording medium. 3. The audio data recording / reproducing apparatus according to claim 2, wherein the audio data recording / reproducing apparatus can be handled well.

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