 |
Description  |
|
|
BACKGROUND OF THE
INVENTION
Field of the Invention
This invention relates to a method and a system for transmitting compressed audio data without expansion and for recording the data on the receiving side as compressed signals in which the status of a recording medium is detected for announcing
an error and displaying an error message.
There has so far been known a magneto-optical disc, termed a mini-disc (trademark), which is a recordable and reproducible disc-shaped recording medium of approximately 64 mm in diameter housed within a cartridge. This magneto-optical disc can
record stereo audio signals continuing for about 74 minutes in accordance with the Adaptive Transform Acoustic Coding (ATRAC) system. This magneto-optical disc can duplicate audio data because it can record the information in distinction from the
conventional digital audio disc known as a compact disc (trademark).
Similarly to the conventional digital audio disc, the magneto-optical disc permits random accessing to the audio data recorded thereon, because an area for Table-Of-Contents information (TOC information) for supervising the recorded audio data is
provided in this magneto-optical disc in addition to an area for recording audio data. Therefore, if audio data is overwritten on the magneto-optical disc carrying recorded audio data, it is possible to erase or edit musical titles by rewriting the TOC
information without erasing actual audio data.
There may be envisaged an audio dubbing system in which, for recording audio data compressed to approximately 1/5 on a magneto-optical disc, compressed audio data are directly stored in a server and read out therefrom so as to be recorded on a
server side hard disc, and in which the compressed audio data are transmitted without expansion for recording on the receiving side.
It may be feared that if, in such audio dubbing system, the recording capacity of a magneto-optical disc is short, the recording area is destroyed partially or entirely, a replay-only disc is inserted or a mistaken recording inhibiting pawl
provided in a cartridge of the magneto-optical disc is locked, the recording operation is not performed as regularly. This defective state can, however, be repaired if, when the user dubs the data from the compact disc to the magneto-optical disc, the
status of the loaded magneto-optical disc is detected in the recording device to issue an alarm, since the user can then halt and re-initiate the dubbing operation even if the transmission of audio data from the compact disc is already started.
On the other hand, in an audio dubbing system in which the audio data transmitted from the server present in a remote place over a transmission route, if the user once requests a desired musical title, the server transmits the audio data without
regard to the status of the recording medium owned by the client.
If the user inadvertently loads the replay-only disc on the recording device, the audio data transmitted cannot be recorded on the replay-only disc, such that the audio data transmitted cannot be dubbed on the client side.
Since the server charges the fee for the transmitted audio data, there is incurred monetary loss to the user.
Moreover, since the transmitted audio data is in the form of non-decoded compressed data, the user cannot tentatively hear the audio data, such that the transmitted audio data is of no avail to the user.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a dubbing system in which meaningless charging can be evaded and in which the status of the loaded recording medium is detected on the side of the recording device, such that, if the detected
state is good or bad, delivery of the audio data is or is not requested to the server, respectively.
It is another object of the present invention to provide a dubbing system in which the rest of money deposited on the recording device, such as rest of coin inserted or a pre-paid card inserted on the recording device side, is detected and, if
the detected state is good or bad, request for delivery of audio data is or is not made to the server side, respectively.
In one aspect, the present invention provides a transmitting/receiving system including a transmitter and a receiver, in which the transmitter has memory means for storing plural compressed data and transmitting means for transmitting compressed
data selected by a user, and in which the receiver has receiver means for receiving the compressed data transmitted from the transmitter, recording means for recording the compressed data on a recording medium, detection means for detecting the recording
inhibiting information of the recording medium, display means for displaying an error message in order to advise the user of the recording inhibition responsive to detection by the detection means and transmitting means for transmitting the request
information to the transmitter as to if the recording medium is normal responsive to the detection result by the detection means.
In another aspect, the present invention provides a data transmitting/receiving method including the steps of detecting the recording inhibiting information of a recording medium, displaying an error message for advising the user of the effect of
recording inhibition depending on the result of detection, transmitting means for transmitting the request information to a server if the recording medium is normal in accordance with the detected result, receiving the compressed data transmitted from
the server and recording the compressed data on the recording medium.
With the audio data recording method and apparatus according to the present invention, an error message is displayed on the display means if audio data cannot be recorded as regularly. This enables display as to whether or not recording can be
made correctly before recording on the recording medium to enable audio data to be recorded reliably. Also, with the present audio data recording method and apparatus, since the error message is displayed, the user can accommodate the contents of the
error.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of the overall dubbing system embodying the present invention.
FIG. 2 shows the data structure on a magneto-optical disc embodying the present invention.
FIG. 3 similarly shows the data structure on a magneto-optical disc embodying the present invention.
FIG. 4 shows the data structure for a U-TOC sector 0 which is a management area on a magneto-optical disc embodying the present invention.
FIG. 5 shows the data structure of a slot on a U-TOC which is a management area on a magneto-optical disc embodying the present invention.
FIG. 6 shows the data structure of a track mode on a U-TOC which is a management area on a magneto-optical disc embodying the present invention.
FIG. 7 is a diagrammatic view showing the linking state of each slot on a U-TOC which is a management area on a magneto-optical disc embodying the present invention.
FIG. 8 shows a data structure for a U-TOC sector 1 which is a management area on a magneto-optical disc embodying the present invention.
FIG. 9 shows a data structure for a U-TOC sector 2 which is a management area on a magneto-optical disc embodying the present invention.
FIG. 10 shows a data structure for a U-TOC sector 4 which is a management area on a magneto-optical disc embodying the present invention.
FIG. 11 is a detailed block diagram of a recording device shown in FIG. 1.
FIG. 12A is a block diagram showing the connecting state between an audio transferring unit 10 and a recording unit 20 according to the present invention.
FIG. 12B is a timing chart for illustrating compressed audio data ATRAC sent from the audio transferring unit 10 to the recording unit 20, a request signal Data Req sent from the recording unit 20 to the audio transferring unit 10 and the
processing timing on the recording unit.
FIG. 12C is a timing chart for illustrating a command signal Command sent from the audio transferring unit 10 to the recording unit 20, an acknowledgment signal ACK sent from the recording unit 20 to the audio transferring unit 10 and the
processing timing on the recording unit.
FIG. 13 is a flowchart for illustrating the dubbing processing by the recording unit 20 embodying the present invention.
FIG. 14A shows the management information for the music program stored in a server embodying the present invention.
FIG. 14B shows the management information for the music program recorded on an optical disc D embodying the present invention.
FIG. 15A is a timing chart for compressed audio data ATRAC sent from the audio transferring unit 10 to the recording unit 20.
FIG. 15B is a timing chart of a request signal DATA Req sent from the recording unit 20 to the audio transferring unit 10.
FIG. 15C is a timing chart for illustrating a command signal Command sent from the audio transferring unit 10 to the recording unit 20.
FIG. 15D is a timing chart for illustrating an acknowledgment signal ACK sent from the recording unit 20 to the audio transferring unit 10.
FIG. 15E is a timing chart for illustrating the timing of processing on the recording unit.
FIG. 16A is a timing chart for illustrating a command signal Command sent from the audio transferring unit 10 to the recording unit 20.
FIG. 16B is a timing chart for illustrating an acknowledgment signal ACK sent from the recording unit 20 to the audio transferring unit 10.
FIG. 16C is a timing chart for illustrating the timing of processing on the recording unit.
FIG. 16D is a diagrammatic view showing the contents of the management information TOC formed on the optical disc D.
FIG. 17A is a timing chart for illustrating a command signal Command sent from the audio transferring unit 10 to the recording unit 20.
FIG. 17B is a timing chart for illustrating an acknowledgment signal ACK sent from the recording unit 20 to the audio transferring unit 10.
FIG. 17C is a timing chart for illustrating the timing of processing on the recording unit.
FIG. 17D is a diagrammatic view showing the contents of the management information TOC formed on the optical disc D.
FIG. 18A is a timing chart for illustrating a command signal Command sent from the audio transferring unit 10 to the recording unit 20.
FIG. 18B is a timing chart for illustrating an acknowledgment signal ACK sent from the recording unit 20 to the audio transferring unit 10.
FIG. 18C is a timing chart for illustrating the timing of processing on the recording unit.
FIG. 18D is a diagrammatic view showing the contents of the management information TOC formed on the optical disc D.
FIG. 19 illustrates the contents recorded on the optical disc D.
FIG. 20 is an overall block diagram showing a second embodiment of the present invention.
FIG. 21 is a flowchart for illustrating the confirming sequence prior to the recording operation by the recording unit 20.
DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to the drawings, preferred embodiments of an audio dubbing system according to the present invention will be explained in detail.
FIG. 1 shows an audio dubbing system embodying the present invention. An audio dubbing system 1 has an audio transfer unit 10 including a main controller 11, a server 12, an actuating input unit 13 and a display unit 14, a recording unit 20 for
recording audio data on a portable recording medium and a connection cable 2 for interconnecting the audio transfer unit 10 and the recording unit 20.
In this audio dubbing system 1, audio data is previously stored in a server 12 of the audio transfer unit 10, so that the user will select desired audio data from the audio data stored in the server 12 for recording on a recording medium.
That is, the present audio dubbing system 1 is such a system purveying musical contents to the user by recording audio data on a recording medium owned by the user, instead of purveying contents of audio data stored in a medium such as compact
disc or audio tape. For example, this audio dubbing system 1 can be installed on a railroad station or a retail store to furnish the chargeable musical contents to the user or on a music studio for contents management purposes.
The schematics of the contents purveying system of the present audio dubbing system 1 are hereinafter explained.
In the server 12 of the audio dubbing system 1, musical contents of musical titles, each continuing for several minutes, such as top 100 titles of the latest hit chart, are stored as audio data. The user confirms the contents purveyed by the
audio dubbing system 1 by a display 14 and, if he or she finds desired contents, he or she selects one or plural contents using the actuating input unit 13. The user loads the recording medium D on the recording unit 20 and actuates the actuating input
unit 13 to initiate the recording.
If the user initiates the recording operation, the main controller 11 of the audio transfer unit 10 furnishes audio data of the contents designated by the user, from among the contents stored in the server 12, to the recording unit 20. The
recording unit 20 records the audio data furnished from the audio transfer unit 10 in a recordable area of the recording medium.
When the recording of audio data of the contents desired by the user comes to a close, the audio dubbing system 1 terminates the purveying of the contents.
Although the server 12 is included in the audio transfer unit 10 in FIG. 1, the server 12 can be installed in an information center located on a distant place and can be communicated with a unit which includes the main controller 11, the display
unit 14, the actuating input unit 13, and the recording unit 20 using ISDN and phone line.
In the following description of the present audio dubbing system 1, it is assumed that the recording medium handled by the audio dubbing system 1 of the present embodiment is a magneto-optical disc which is a recordable and reproducible disc
provided in the format termed a mini-disc (trademark).
This magneto-optical disc, termed the mini-disc, is a disc-shaped recording medium approximately 64 mm in diameter, held in a cartridge, and can record approximately 74 minutes of stereo audio data using a Adaptive Transform Acoustic Coding
(ATRAC) system. This magneto-optical disc, termed the so-called mini-disc, is herein referred to simply as an optical disc D.
Since the audio dubbing system 1 records the audio data compressed in accordance with the ATRAC system on the optical disc D, audio data of the contents stored in the server 12 are previously compressed in accordance with the ATRAC system. The
audio data, compressed in accordance with the ATRAC system, is directly recorded on the optical disc D, without processing the audio data with decoding or encoding. The audio data compressed by the ATRAC system is referred to herein as ATRAC data.
Thus, a connection cable 2 used fro transferring audio data from the audio transfer unit 10 to the recording unit 20 transfers the ATRAC data. It is noted that control commands or command data (Command) such as table-of-contents (TOC) data of the
optical disc D are sent over the connection cable 2 in accordance with the transmission protocol which will be explained subsequently.
The format of data of the optical disc D used in the audio dubbing system 1 will now be explained.
Data can be written on the optical disc D in units corresponding to an integer number times of a cluster, as shown in FIG. 2. It is noted that an audio signal of approximately 2.04 second is produced on reproducing the ATRAC data recorded in
each cluster.
It is noted that each cluster is made up of 3 linking sectors, 1 sub-data sector and 32 main sectors for recording audio data compressed in accordance with the ATRAC system, the sum of which is 36 sectors. Each sector is a unit made up of 2352
byte data.
Since the format of the optical disc D uses an error correction system of the Advanced Cross Interleaving Reed Solomon Code (ACIRC) system, the linking sector is used as a sector allocated for completing the error-correcting interleaving within
the cluster. That is, the linking sector is a waste sector for taking into account the interleaving in the error correction so that the data rewriting will be made on the cluster basis.
The sub-data sector is a reserve area.
The optical disc D handles 424 byte data compressed in accordance with the ATRAC system in units termed a sound group. This sound group allocates 212 byte data for each of the left and right channels. This sound group allocates 212 byte data
for each of the left and right channels. On expansion, the sound-group-based compressed data corresponds to 512 samples of left and right channels. These 512 samples of data correspond to 2048 byte data, more specifically, 512 samples.times.16
bits.times.2 channels.div.8 bits =2048 bytes. 11 of the sound groups make up two sectors, as shown in FIG. 3 .
The recording area of the optical disc D is split into a program area for recording audio data compressed in accordance with the ATRAC system, a User Table-Of-Contents (U-TOC) area as a management area for recording management data for managing
audio data recorded in the program area, and a Pre-mastered Table-Of-Contents (P-TOC) area as a lead-in area.
In this optical disc D, musical numbers can be erased or edited by rewriting the U-TOC information instead of physically erasing the actual music data for rewriting. For example, in the case of the optical disc D having recorded thereon five
musical titles, if a start address and an end address of a third musical title are specified as a recordable area, the third musical number cannot be reproduced. Thus, when recording the ATRAC data on the optical disc D, this U-TOC information needs to
be re-written simultaneously. This U-TOC is explained hereinbelow. The unit of audio data recorded on the optical disc D is simply termed `track`. This track is the unit of a musical title corresponding to the contents of the music purveyed by the
above-described audio dubbing system 1.
The U-TOC of the optical disc D s made up of from U-TOC sector 0 to U-TOC sector 15, totaling 16 sectors. The U-TOC sector n, where n denotes 1 to 15, is indicated simply as U-TOCn.
FIG. 4 shows data recorded on the U-TOC0. the data recorded on the U-TOC0 is partitioned into bytes and represented as a slot for convenience. Each slot is specified by numerical figures from 0 to 587 on the ordinate in FIG. 4 by slot number of
from 1 to 4 on the abscissa. The same applies for the U-TOC1 and so forth.
In the U-TOC0, there are recorded 12 byte header data followed by ClusterH and ClusterL specifying the address of the TOC0. In the TOC0, there are recorded a Maker code, specifying the maker of the optical disc D, a Model code, specifying the
model of the optical disc D, FirstTNO specifying the track number of the first track of the optical disc D and LastTNO specifying the rack number of the last track, beginning from a slot 7.times.1. In the U-TOC0, Used Sectors specifying the use state of
the sectors and DiscSerialNo specifying the serial number of the optical disc D are recorded in slot 8.times.4 and in slot 10.times.4, respectively.
In the U-TOC0, there are also recorded DiscID specifying the ID number of the optical disc D, a pointer P-DFA (Pointer for Defective Area) specifying the slot having recorded therein the start address of an area for recording the defective
address information produced on the optical disc D, a pointer P-EMPTY (Pointer for Empty Slot) specifying the use state of a slot and a pointer P-FRA (Pointer for Freely Area) specifying a slot having recorded therein the start address of an area used
for managing the recordable area, beginning from a slot 11.times.1. In the U-TOC0, there is also recorded a pointer P-TNOn specifying the slot having recorded therein a start address of each track recorded on the optical disc D from a slot 12.times.2 to
a slot 75.times.4, n specifying the track number of each track. Since 255 tracks can be provided on the optical disc D, n is an integer from 1 to 255.
In the U-TOC0, there are also recorded a start address and an end address of each track, link information Link-P and a track mode (Trackmode) from a slot 78.times.1 to a slot 587.times.4. In the U-TOC0, there are further recorded 255.times.4
slots for recording the start address and the end address. The start and end addresses are recorded in a slot associated with each track.
Therefore, the pointer recorded in each of the above-mentioned P-DFA, P-EMPTY and in P-FRA indicate a slot of a start address represented from the slot 78.times.1.
The above-mentioned start and end addresses are represented in 3 bytes=24 bits, as shown in FIG. 5. In the start and end addresses, a cluster address, a sector address and an address of the sound group are recorded in the first 14 bits, next 6
bits and the trailing 4 bits, respectively.
The track mode (Trackmode) is represented by 1 byte=8 bit data, as shown in FIG. 6. In the track mode (Trackmode), the recording protect information, duplication protect information, generation information, audio information, erasure reserve
information, monaural or stereo information and the emphasis information are recorded in the first bit, second bit, thirds bit, fourth bit, fifth and sixth bits, seventh bit and in the eighth bit, respectively. That is, the relevant information proper
to each track is recorded in the track mode (Trackmode).
The link information P-Link is a pointer used for tracing from which start address the next data is recorded in case the same track is not recorded as a continuous data stream on the optical disc D, that is in case data of the same track is
recorded discretely in the recording area of the optical disc. For example, if, in reproducing a track, data from the start address of the slot 586.times.1 needs to be reproduced next to the end address represented in the slot 78.times.1, the link
information Link-P of the slot 80.times.4 specifies the slot 581.times.1.
That is, in the optical disc D, data need not necessarily be recorded on the recording medium, that is as a continuous data stream, but a sequential data string may be recorded discretely. If data is recorded discretely, data continuity is
indicated by this link information P-Link, such that, by transiently storing read-out data in a memory during reproduction and by writing data in the memory at a quicker rate than the data read-out rate, continuous data can be reproduced without
interruptions.
If data shorter than the recorded program is overwritten on the previously recorded data, efficient recording can be achieved by specifying the redundant area as a recordable area (P-FRA) without rasing the redundant area.
The method for linking discrete areas is now explained with reference to FIG. 7 taking an example of the recordable area P-FRA.
The area specified by the start point address and the end point address of the slot 18h specified by the link information of the slot 03h can be judged to be a recordable area. Further, by tracing the slot 1Fh stated in the link information of
the slot 18h, the area specified by the start point address and the end point address of the slot 1Fh can be judged to be a recordable area.
Further, by tracing the slot 2Bh stated in the link information of the slot 1Fh, the area specified by the start point address and the end point address of the slot 1Fh can be judged to be a recordable area. By tracing slot addresses recorded in
the link information as described above, slots are traced until the link information is equal to 00h.
By tracing the slots beginning from a slot specified by P-FRA until the link information is equal to Null (=00h), it is possible to link on the memory plural fractional parts making up a track discretely recorded on the disc.
Although P-FRA is taken as an example for explanation, discretely present fractional parts can similarly linked for P-DFA, P-EMPTY and T-TNO)0 to 255.
FIG. 8 shows data recorded on the U-TOC1.
In the U-TOC1, the title of each track and title of the optical disc D in its entirety are managed.
If the recording track is audio data, the title of the optical disc D in its entirety and the title of each track correspond to the album title and the name of the performer and to the name of the musical title, respectively.
The letter information for each track is recorded in the slot specified by P-TNAn (n is 1 to 255), and if there are a large number of letters, the link information is used to connect plural slots for recording.
FIG. 9 shows data recorded on the U-TOC2.
In U-TOC2, the recording time and data for each program recorded in the program area is managed in the similar configuration to the above-mentioned U-TOC0.
FIG. 10 shows data recorded in the U-TOC4.
In U-TOC4, the title of each program recorded in the program area is managed in the similar configuration to the above-mentioned U-TOC0 so that the Japanese syllabic characters and kanji can be used as fonts of the entire title of the entire
optical disc D.
Referring to FIG. 11, the configuration of the audio dubbing system 1, added to with that of the recording unit 20 as described above, will be explained in detail.
FIG. 11 shows the block diagram of the audio dubbing system 1 embodying the present invention. This audio dubbing system 1 is made up of an audio transfer unit 10, recording unit 20 and a connection cable 2 interconnecting the audio dubbing
system 1 and the recording unit 20. The audio transfer unit 10 has a main controller 11, a server 12, actuating input unit 13 and a display unit 14. The recording unit 20 is used for recording audio data in a portable type recording medium.
The recording unit 20 includes a Random-Access Memory (RAM) 22 for storing data sent from the audio transfer unit 10, and a memory controller 21 for controlling the RAM 22. The recording unit 20 also includes an encoding/decoding circuit 23 for
decoding and encoding data and a magnetic head driving circuit 24 for driving a magnetic head 25 and an optical pickup 26 for illuminating the laser light on the optical disc D for detecting the reflected light. The recording unit 20 also includes a RF
amplifier 27 for reproducing the Focusing Error signals (FE), Push-Pull signals (PP) and Magneto-optical playback signals (MO) from the reflected light detected from the optical pickup 26. The recording unit 20 also includes an address decoder 28 for
reproducing signals corresponding to the wobbling of the groove formed in the guide groove of the optical disc D based on the Push-Pull signals (PP) from the RF amplifier 27 for decoding the ADIP and a spindle motor 29 for rotationally driving the
optical disc D. The recording unit 20 further includes a thread unit 30 for radially moving the optical pickup 26 along the radius of the optical disc D.
The recording unit 20 includes a servo circuit 31 for controlling the focusing servo, thread servo and spindle servo based on the Focusing Error signals (FE) and the Push-Pull signals (PP) and a system controller 32 for controlling the memory
controller 21, encoding/decoding circuit 23 and the servo circuit 31.
The optical pickup 26 illuminates the laser light on the optical disc D from the laser diode via an objective lens. The optical pickup 26 also detects the reflected light from the optical disc D by a photodetector to send the detection current
to the RF amplifier 27.
The RF amplifier 27 generates the Focusing Error signals (FE), Push-Pull signals (PP) and the Magneto-optical playback signals (MO) based on the detection current from the photodetector. The RF amplifier 27 sends the generated Focusing Error
signals (FE) to the servo circuit 30, while sending the Push-Pull signals (PP) to the address decoder 28 and the servo circuit 30, while sending the Magneto-optical playback signals (MO) to the encoding/decoding circuit 23.
The servo circuit 31 drives the objective lens via a biaxial unit of the optical pickup 26, based on the furnished Focusing Error signals (FE) and the Push-Pull signals (PP), in order to perform tracking and focusing servo control of the light
beam radiated to the optical disc D. The servo circuit 31 drives a thread unit 30 based on the Push-Pull signals (PP) to perform thread servo control for driving the optical pickup 26 radially of the optical disc D. The servo circuit 31 performs spindle
servo control of driving the spindle motor 29 to cause the optical disc D to be rotated at a Constant Linear Velocity (CLV) based on the spindle error signals from an optical disc rotation detection circuit, not shown.
The address decoder 28 regenerates the address information from the wobbled signals corresponding to the groove wobbling formed in the guide groove of he optical disc D.
The encoding/decoding circuit 23 converts the Magneto-optical playback signals (MO) from the RF amplifier 27 into bi-level signals and decodes the bi-level signals in accordance with the Eight-to-Fourteen Modulation (EFM) system while also
decoding error correction in accordance with the Cross-Interleaved Reed-Solomon Coding (CIRC). The encoding/decoding circuit 23 appends error correction codes to the recording signals supplied from the memory controller 21 in accordance with the CIRC
system and modulates the resulting signal in accordance with the EFM system to send the recording signal to the magnetic head driving circuit 24.
The magnetic head driving circuit 24 drives the magnetic head 25 based on recording signals from the encoding/decoding circuit 23 to apply a modulating magnetic field on the optical disc D by way of recording the recording signals.
The memory controller 21 controls the writing and readout of the ATRAC data to be stored on the RAM 22. This memory controller 21 causes the ATRAC data supplied from the audio transfer unit 10 transiently in the RAM 22 to send the transiently
stored data subsequently to the encoding/decoding circuit 23.
The system controller 32 performs control of the recording unit 20 in its entirety. For example, the system controller 32 controls the memory controller 21, encoding/decoding circuit 23 and the servo circuit 31. The system controller 32 also
controls the circuits adapted for exchanging control data with the audio transfer unit 10, as will be explained subsequently.
By the above structure, the recording unit 20 of the audio dubbing system records ATRAC data sent from the | | |
