JP2005276349A - Disk playback apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To conduct playback of a disk while confirming a compressed file regardless of the external identifier added to the compressed file even though a user inadvertently adds other external identifier to the compressed file such as a music file or the like. <P>SOLUTION: When compressed data are reproduced from a disk of a compressed file having the compressed data to which an external identifier is added in accordance with a compression system, discrimination is made to determine whether reproducing is possible or not by confirming the compression form of the compressed data regardless of the external identifier. When it is judged that reproducing is possible, reproducing of the compressed data is conducted. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a disk playback device, and in particular, when playing back compressed data from a disk on which a file having compressed data is recorded, the compressed data is checked regardless of the extension added to the file. The present invention relates to a disk reproducing apparatus for reproducing data.

  In recent years, music data has been distributed using a network with the spread of the Internet and the like. In such music data distribution, music data is transmitted in order to shorten the time required for data transmission / reception on the network. Are compressed and distributed as music files. Various compression methods are known.

  For example, in addition to MP3 (MPEG-1 Audio Layer III) which is one of audio compression methods used in MPEG-1, WMA (Windows (registered trademark) Media Audio) which is an audio compression format of Microsoft (registered trademark). AAC (Advanced Audio Coding), which is an audio compression method used in MPEG-2 or MPEG-4, is known.

  The music file distributed over the network is played back by an audio function provided in the computer after being imported into the computer. Further, the music file is further converted by a user into, for example, a CD-R (Compact Disc Recordable) or a CD. -A music file may be played back by a disc playback device written on a writable disc such as RW (Compact Disc Rewriteable).

  As described above, when a user writes a music file on a disc, a disc creation / editing function (ripping software) is generally used. In this case, the user generally adds an extension to the music file. When a music file is played back by the disc playback device, the disc playback device checks the extension and plays back the music file. For example, an extension “.mp3” is added to a music file compressed in the MP3 format, and the disc playback apparatus confirms this extension “.mp3” and plays the music file.

  By the way, when a user adds an extension to a music file, an extension different from the extension corresponding to the music file may be mistakenly added. (For example, when an extension “.mp3” is added to a file compressed in a format other than the MP3 format), when a music file is played back on the disc playback device, it is played back as noise or in a silent state. The reproduction continues for several minutes as it is, and the user feels uncomfortable.

  In order to deal with such a situation, the existence of an extension to be added to the compressed music file is searched, and whether or not the file with the extension is a compressed music file is checked, and the extension Plays only the data that constitutes a file that has been confirmed to store compressed music data among the files that have children added, and adds an extension that indicates that it is a compressed music file to a file that is not compressed music data Even if it has been done, there is one in which the file is not reproduced (see, for example, Patent Document 1).

JP 2002-196791 (pages 3 to 7, FIGS. 1 to 6)

  However, since the conventional disc reproducing apparatus is configured as described above, if the user accidentally adds an extension indicating that the music data is not compressed music data to the music file that is compressed music data, In spite of this, there is a problem that the result cannot be reproduced by the disc reproducing apparatus.

  In the situation as described above, generally, the user is not aware of the mistake in attaching the extension, and when a situation occurs in which the music file cannot be played back by the disc playback device, there is a cause for the disc playback device itself (for example, a failure has occurred). However, even if it is not actually a failure, it may cause a failure claim against the manufacturer.

  The present invention has been made to solve the above-described problems, and even if a user accidentally adds another extension to a compressed file such as a music file, the extension added to the compressed file is changed. It is an object of the present invention to obtain a disc reproducing apparatus capable of confirming a compressed file and reproducing a disc.

  The disc playback apparatus according to the present invention confirms the compression format of the compressed data regardless of the extension when the compressed data is played back from the disc on which the file having the extension and the extension added according to the compression method is recorded. It is determined whether or not the data can be reproduced, and when it is determined that the data can be reproduced, the compressed data is reproduced.

  According to the present invention, since it is configured to determine whether or not the compressed data can be reproduced by checking the compression format regardless of the extension, when the user records a file such as a music file on the disc. Even if a compression format and a child extension are added by mistake, the compressed data can be reproduced, and the extension is attached even though the compressed data is a compression format that can be reproduced by the disc playback device. There is an effect that it is possible to prevent a situation where reproduction is impossible due to a mistake.

Embodiment 1 FIG.
FIG. 1 is a block diagram showing the configuration of a disk playback apparatus according to Embodiment 1 of the present invention. A disk D played back by this disk playback apparatus includes MP3 (MPEG-1 Audio Layer III), WMA ( A music file compressed by one of Windows (registered trademark) Media Audio) or AAC (Advanced Audio coding) format is recorded, and the music file compressed by MP3 format is “.mp3”, by WMA format An extension “.wma” is added to the compressed music file, and an extension “.aac” is added to the music file compressed by the AAC method.

  TOC (Table of Contents) information is stored in the lead-in area formed at the top of the disk D, and the file names and extensions of all music files stored in the disk D are included in the TOC information. In addition, the recording position of each music file on the disk D is included.

  As a disc D, an audio CD (CD-DA: Compact Disc Digital Audio) such as a CD-R (Compact Disc Re- cordable), CD-RW (Compact Disc Re-Writable), an audio MD (mini disc), and a DVD on which audio data is recorded -R (Digital Versatile Disc Recordable), DVD-RW (Digital Versatile Disc Rewriteable), and DVD-RAM (Digital Versatile Disc Random Access Memory) are used.

  Here, it is assumed that the user records a music file from the computer to the disk D, and at this time, the user adds an extension to the music file. At this time, as described above, the user may mistake the extension.

  The illustrated disk playback apparatus has a deck unit 10 and an audio set unit 20, and the deck unit 10 includes a deck 11, a DSP (digital signal processor) 12, a motor driver 13, a disk detection unit 14, a microcomputer (hereinafter referred to as a microcomputer). 15) and a memory 16.

  The microcomputer 15 includes a communication port unit 15a, an interrupt control unit 15b, a CPU 15c, a ROM 15d, and a RAM 15e. The ROM 15d stores a program such as a control program, and the RAM 15e temporarily stores work data for the CPU 15c. It is used as an area to perform. The communication port unit 15a is a port for data transmission / reception between the CPU 15c and the audio set unit 20, and data transmission / reception between the CPU 15c, the disk detection unit 14, and the DSP 12. The interrupt control unit 15b performs interrupt control on the CPU 15c.

  The deck 11 is a mechanism (mechanical) for driving the disk D. The deck 11 includes a pickup 11a. When the disk D is inserted into the deck 11, the deck 11 detects a disk insertion signal indicating the disk detection. Send to part 14. When the disc detection unit 14 receives a disc insertion signal from the deck 11, the disc detection signal is sent to the microcomputer 15, and the CPU 15c sends a reproduction instruction to the DSP 12 in accordance with the disc detection signal.

  The motor driver 13 controls the spindle motor and sled motor of the deck 11 based on the output (reproduction output) from the DSP 12. That is, the deck 11 drives a spindle motor (not shown) according to a control signal from the motor driver 13 to rotate the disk D, and drives a sled motor (not shown) to move the pickup 11a. It will be.

  The pickup 11a is moved by a sled motor and positioned, and then reads data from the rotating disk D. The data read by the pickup 11a is given to the DSP 12.

  The DSP 12 performs signal processing on the data output from the pickup 11a in response to a reproduction instruction from the CPU 15c, and reproduces the data recorded on the disk D. For example, the DSP 12 sends the data output from the pickup 11 a other than the compressed data (for example, TOC information and header information) to the microcomputer 15, and the compressed data is decoded and sent to the audio set unit 20.

  In the illustrated disk reproducing apparatus, the memory 16 is for so-called shock proof, and if the disk reproducing apparatus is mounted on a moving body such as a vehicle, data reproduction may not be performed satisfactorily due to vibration or the like. is there. For this reason, the DSP 12 temporarily stores the reproducible data in the memory 16 sequentially under the control of the CPU 15c.

  This data accumulation is performed by, for example, a double speed process (first processing speed), and the data accumulated in the memory 16 is read from the memory 16 by a first-in first-out method and reproduced by the DSP 12. Data reproduction is performed at a single speed (second processing speed), for example, and if data reproduction and data storage are performed at a speed that is more than double, even if reading / determination processing is performed, the time delay is Is not conscious.

  For example, even if there is a state where the pickup 11a does not move normally due to vibration or the like, that is, there is a state where data cannot be read for a short time, reproduction is performed using the data stored in the memory 16. For example, reproduction can be performed without interruption of sound (for example, accumulation of data is about 10 seconds in reproduction time).

  The audio set unit 20 includes an operation button 21, a microcomputer 22, a liquid crystal display (LCD) 23, an audio control unit 24, and an amplification unit 25. The microcomputer 22 includes a communication port unit 22a, a CPU 22b, and an interrupt control unit 22c. ROM 22d and RAM 22e. The ROM 22d stores a program such as a control program, and the RAM 22e is used as an area for temporarily storing work data for the CPU 22b.

  The communication port unit 22a is a port for transmitting and receiving data between the CPU 22b and the deck unit 10, and interrupt control is performed on the CPU 22b by the interrupt control unit 22c.

  When disc playback is selected by the operation button 21, a disc playback instruction is sent from the CPU 22b to the CPU 15c via the communication ports 22a and 15a. The CPU 15c, as described above, of the disc D inserted into the deck 11 is sent. Perform playback control. When the reproduction is started, the CPU 22b displays various messages on the LCD 23 according to the data sent from the CPU 15c.

  The audio control unit 24 generates an analog sound signal based on the reproduction music data (digital data) sent from the DSP 12 and sends the analog sound signal to the amplification unit 25. The amplifying unit 25 amplifies the analog sound signal and applies the amplified signal to the speakers 26 and 27, and the sound (music) is transmitted from the speakers 26 and 27.

Next, the operation will be described.
When the disc D is inserted into the deck 11, the music file recorded on the disc D is played as described above. In this example, the music file is recorded on the disc D by the MP3 method. Shall.

  FIG. 2 is a diagram showing a format example of a music file recorded on the disk D. Here, a format example of an MP3 file is shown (hereinafter referred to as an MP3 data stream). The MP3 data stream has a plurality of frames 1, 2, 3,..., And each frame includes a header, side information, and main data. The header is composed of 32 bits (4 bytes) as described later, and the side information is information necessary for decoding main data such as window information and area designation. The main data is data including music data.

  FIG. 3 is a diagram showing the configuration of the header shown in FIG. 2, and the header includes information indicating the type of the entire MP3 data such as the bit rate and the sampling frequency. In FIG. 3, the meaning of each element (field) is defined by the MP3 standard and will not be described. However, in the header shown in FIG. 3, when the compression format is MP3, the 12 bits of Syncword are all “1”. That is, if there are 12 consecutive “1” s at the beginning of the header, the header is an MP3 header.

  1 and 4, when the disc D is inserted into the deck 11 and the music file to be played back is selected by the operation button 21 (step ST1), the CPU 15c controls the DSP 12 to control the contents of the music file. Is checked (step ST2). First, in the case of MP3, since all 12 bits of syncword are “1”, the CPU 15c checks whether or not “1” is continuously 12 times (with a reproducible header: step ST3). If “1” is 12 times, the CPU 15c determines that the header of MP3 exists.

  If the CPU 15c determines that the header exists, each element (field) following the syncword is checked (data configuration check: step ST4) to determine whether or not the header has the MP3 data configuration. That is, it is determined whether or not it has a reproducible data configuration (step ST5). If it is determined in step ST5 that the data structure is reproducible, the CPU 15c determines whether or not an extension corresponding to the data structure is added to the music file for the first time (step ST6).

  If the corresponding extension is added, the CPU 15c controls the DSP 12 to decode the music file as described above (data decoding: step ST7) and temporarily stores the data in the memory 16 (step ST). ST8) Play music file.

  By the way, in reproducing a music file, the structure of the header is checked before reproduction, but due to this header structure check, the reproduction of the music file is delayed by that amount. For this reason, in the illustrated example, the CPU (first processing means) 15c controls the DSP 12 for pre-reading for the second and subsequent music pieces and checks the data configuration in advance. That is, as shown in FIG. 5, in a state where data is stored in the memory (storage means) 16 from the middle of the first music to the middle of the second music, the CPU 15c prefetches the data from the beginning of the second music via the DSP 12. Thus, the data structure of the second song is checked. In the example shown in FIG. 5, the first half of the first song is reproduced via the audio set unit (second processing means) 20.

  If it is determined in step ST5 that the CPU 15c does not have a reproducible data structure, the CPU 15c checks the header and data structure again to determine whether or not the data can be replayed (step ST9). If it is determined that playback is not possible, information indicating that playback is not possible is passed to the CPU 22b, and the CPU 22b displays on the LCD 23 that playback is not possible. On the other hand, if it is determined that reproduction is possible, the CPU 15c proceeds to step ST6.

  In step ST6, if there is no corresponding extension, the CPU 15c checks the header and data structure again to determine whether or not playback is possible (step ST10), and if playback is possible, performs step ST7. If it is not reproducible, it is displayed on the LCD 23 that it cannot be replayed as described above.

  As is apparent from the above description, the CPU 15c functions as a determination unit and the DSP 12 functions as a reproduction unit.

  As described above, according to the first embodiment, the header in the music file is confirmed, the compression format of the compressed data is checked, and it is determined whether or not playback is possible. When a user records a music file on a disc, the music file can be played even if the extension is wrong and the music file is in a compressed format that can be played on the disc playback device. This has the effect of preventing a situation in which playback cannot be performed due to an incorrect extension. As a result, the user can play the disc even if the extension is wrong.

  According to the first embodiment, after determining whether or not the header is related to a compression method that can be reproduced in accordance with the check of the header, the data configuration is confirmed by this header and whether or not the reproduction is possible. Therefore, it is possible to reliably determine whether or not a music file can be played.

  According to the first embodiment, when it is determined that playback is possible, it is further determined whether or not the extension is an extension corresponding to the compressed data, and this extension does not correspond to the compression format of the music file. In addition, since the header is used to confirm whether or not the music file can be reproduced again, there is an effect that it is possible to determine whether or not the music file can be reproduced with high accuracy regardless of the extension.

  According to the first embodiment, when the compressed data of the music file is stored in the memory, it is performed at the first processing speed, and when the compressed data is read from the memory, it is performed at the second processing speed. Since the speed is set to be twice or more the second processing speed, there is an effect that it is possible to prevent a time delay due to the header check in reproducing the music file.

1 is a block diagram showing a configuration of a disk reproducing device according to Embodiment 1 of the present invention. FIG. It is a figure which shows the data format of MP3 compression format. It is a figure which shows the structure of the header shown in FIG. 6 is a flowchart for explaining a playability determination operation in the disc player shown in FIG. 1. FIG. 2 is a diagram for explaining the timing of accumulation and reading of reproduction data in the disc reproduction apparatus shown in FIG. 1.

Explanation of symbols

  10 deck section, 11 deck, 11a pickup, 12 DSP (digital signal processor), 13 motor driver, 14 disk detection section, 15, 22 microcomputer (microcomputer), 15a, 22a communication port section, 15b, 22c interrupt control section, 15c, 22b CPU, 15d, 22d ROM, 15e, 22e RAM, 16 memory, 20 audio set unit, 21 operation buttons, 23 liquid crystal display (LCD), 24 audio control unit, 25 amplification unit, 26, 27 speaker.

Claims (5)

In a disk playback device for playing back the compressed data from a disk on which a file having compressed data with an extension according to the compression method is added,
Determining means for determining whether the compressed data can be reproduced by checking the compression format regardless of the extension;
A disc reproducing apparatus comprising: a reproducing unit that reproduces the compressed data when the determining unit determines that reproduction is possible. The compressed data includes a header in which information related to the compression method is stored at the head portion thereof,
2. The disk reproducing apparatus according to claim 1, wherein the determination unit checks the compression method of the compressed data by checking the header. The determination unit is a header determination unit that determines whether the header is based on a compression method that can be reproduced by the reproduction unit according to the check of the header;
3. The disc reproducing apparatus according to claim 2, further comprising reproduction determining means for determining whether or not reproduction is possible by confirming the data configuration with the header.   When the reproduction determining unit determines that the reproduction is possible, the reproduction determining unit further determines whether or not the extension is an extension corresponding to the compressed data. If the extension does not correspond to the compressed data, the compressed data is restored. 4. The disc reproducing apparatus according to claim 3, wherein whether or not reproduction is possible is confirmed by a header. Storage means for storing compressed data;
A first processing means for storing the compressed data in the storage means at a first processing speed;
A second processing means for reading the compressed data from the storage means at a second processing speed, wherein the first processing speed is at least twice as high as the second processing speed. The disc reproducing apparatus according to claim 1, wherein the disc reproducing apparatus is any one of claims 1 to 4.

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