JP2002352505A - Transmission system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transmission system in which multi-channel audio data such as DVD-Audio is efficiently transmitted in a transmission line using a fixed-length frame such as an MOST(media oriented synchronous transfer) method and in which a copyright protection measure of audio data is applied. SOLUTION: Block data created by a multiplexing means 51 of a transmission device 22 is constituted of 8 frames. The leading first byte of each frame is allocated to a header 101 having Sync or OE, etc., the second byte is allocated to the auxiliary data 102 including AUX data necessary for reproducing audio data and copyright protection information, and remaining bytes are used to transmit the audio data. An enciphering means 52 carries out enciphering process for the second and succeeding bytes of each frame, and the enciphered data is outputted by a communication means 53. A communication means 61 of a receiver 23 receives the enciphered data from a transmitter 22, and the enciphered data is decoded by a decoding means 62 and a demultiplexing means 63 demultiplexes audio data 103 and auxiliary data 102.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission system for transmitting real-time data represented by digital audio data.

[0002]

2. Description of the Related Art As a conventional method of transmitting data recorded on a CD (compact disk) or the like, for example, M
There is a method called OST (Media Oriented Synchronous Transfer). (Reference: Pa
tric heck, et al: "Media Oriented Synchronous Tr
ansfer--A Network Protocol for High Quality, Low C
ost Transfer of Synchronous, Asynchronous, and Con
trol Data on Fiber Optics ", Presented AES 103rd Co
nvention, 1997 September, Preprint 4551.) A conventional data transmission method based on the MOST method will be described below with reference to FIGS. FIG. 11 is a diagram illustrating a data configuration of a frame included in transmission data.
In the conventional transmission method, as shown in FIG. 11A, data is transmitted in a frame transmitted at 44.1 kHz, that is, once every 22.67 microseconds. The data length of one frame is 512 bits. As shown in FIG. 11B, the frame includes a preamble 501, a boundary descriptor 502, a synchronous channel area 503, an asynchronous channel area 504, a control frame 505, frame control data 506, and a parity 507. In addition,
The frame period is not limited to 44.1 kHz, but is
Hz may be used.

Here, a preamble 501, a boundary descriptor 502, and a synchronous channel area 503 in a frame will be described. Asynchronous channel area 504, control frame 505, frame control data 50
6, the parity 507 is not directly related to the present invention, and the description is omitted.

[0004] The preamble 501 is 4-bit data having a predetermined pattern, and is used by a transmitting device and a receiving device that perform transmission to detect a frame boundary. The boundary descriptor 502 is 4-bit data, and indicates how many 4-byte block data the synchronous channel area 503 includes, and is used to indicate a boundary between the synchronous channel area 503 and the asynchronous channel area 504.

[0005] The synchronization channel area 503 is 0-480.
It is bit-length data, and the boundary descriptor 50
2 determines its length. Synchronous channel area 5
03 is used for transmission of real-time data such as voice. Here, the real-time data is data in which each data has a time constraint, and it is required that a transmission delay time can be defined in the transmission.

[0006] Data constituting the synchronization channel area 503 is allocated to the transmitting device and the receiving device as time slots in byte units. That is, the data constituting the synchronization channel area 503 can use a maximum of 60 time slots as the synchronization channel area. The transmitting device and the receiving device are:
Which time slot is used for transmission is assigned in advance, and a set of time slots used for one transmission is defined as a logical channel. The transmitting device transmits data using the allocated time slot, and the receiving device receives data of the allocated time slot. In the MOST system, using one time slot is equivalent to transmitting data at a transmission speed of 352.8 kbps. That is, 1.4112
To transmit CD (Compact Disk) data at a transmission rate of Mbps, the synchronization channel area 503 is required.
May be used.

FIG. 12 is an explanatory diagram for explaining a conventional digital audio data transmission method using a synchronization channel. In the figure, L, R transmitting digital audio data
The contents of the time slot in each of frame 1 and frame 2 used by the channel are shown. The 16-bit audio samples 1 and 3 in each of the frames 1 and 2 are transmitted on the L channel, and the 16-bit audio samples 2 and 4 are transmitted on the R channel.

[0008]

In the conventional transmission system, a system for transmitting two-channel audio data recorded on a CD or the like has been determined.
Since the data transmission method for transmitting multi-channel audio data recorded on Video or DVD-Audio or audio data having a large sample frequency or a large number of quantization bits has not been determined, it is not possible to transmit multi-channel data. There was a problem that could not be done.

Further, in the conventional transmission system, DTCP
(Digital Transmission Content Protection Specific
)), there are the following two problems in encrypting data for the purpose of copyright protection as represented by: The first problem is that when a transmission device performs encryption in units of 8 bytes, which is commonly used, the data of each frame is not always a multiple of 8 bytes in the conventional transmission method. The problem is that the encryption is not completed within the frame.
In P, copyright protection information is to be transmitted.
The conventional transmission method has a problem that the transmission method is not determined.

The present invention solves these problems, and performs efficient transmission of multi-channel audio data such as DVD-Audio on a transmission path using a fixed-length frame such as a MOST system, and transmits the audio data. An object of the present invention is to provide a transmission system capable of realizing copyright protection.

[0011]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above object, and a transmission system according to a first aspect of the present invention provides multi-channel audio data and auxiliary data necessary for reproducing the audio data. A transmitting device for transmitting the
A receiving device for receiving audio data and auxiliary data transmitted from the transmitting device, wherein the auxiliary data includes channel assignment information of the audio data. .

[0012] The transmission system according to claim 2 of the present invention comprises:
2. The transmission system according to claim 1, wherein the auxiliary data further includes sampling frequency information.

[0013] The transmission system according to claim 3 of the present invention comprises:
2. The transmission system according to claim 1, wherein the auxiliary data further includes quantization bit number information.

[0014] The transmission system according to claim 4 of the present invention comprises:
2. The transmission system according to claim 1, wherein the channel assignment information of the audio data is based on a DVD-Audio standard.

[0015] The transmission system according to claim 5 of the present invention comprises:
2. The transmission system according to claim 1, wherein the transmitting device includes multiplexing means for multiplexing auxiliary data with audio data to generate multiplexed data, and the receiving device includes a multiplexed data transmitted from the transmitting device. Receiving means for receiving voice data and auxiliary data.

[0016] The transmission system according to claim 6 of the present invention comprises:
2. The transmission system according to claim 1, wherein, when transmitting the audio data having different sampling frequencies to the receiving device, the transmitting device multiplexes and transmits the audio data generated earlier in time. Is what you do.

[0017] The transmission system according to claim 7 of the present invention comprises:
2. The transmission system according to claim 1, wherein the transmission method of the audio data and the auxiliary data is configured to time-divide the data into transmission frames, and to transmit the audio data,
It is characterized in that certain bits are allocated in each transmission frame.

[0018] The transmission system according to claim 8 of the present invention comprises:
2. The transmission system according to claim 1, wherein the transmission method of the audio data and the auxiliary data is in accordance with the MOST method.

A transmission system according to a ninth aspect of the present invention comprises:
A transmission system comprising: a transmitting device that transmits digital data and auxiliary data necessary for reproducing the digital data; and a receiving device that receives the digital data and the auxiliary data transmitted from the transmitting device, wherein the transmitting device Is
Multiplexing means for multiplexing auxiliary data with digital data and creating block data composed of n frames which is a multiple of a predetermined encryption unit, and encrypting the block data in the predetermined encryption unit; Encryption means for creating encrypted data, wherein the receiving device decodes the encrypted data transmitted from the transmission device, and digitally converts the block data decrypted by the decryption means. And a separating unit for separating data and auxiliary data, wherein the block data is composed of a plurality of frames of an encryption unit.

A transmission system according to a tenth aspect of the present invention is the transmission system according to the ninth aspect, wherein the predetermined encryption unit is 8 bytes.

[0021] In a transmission system according to an eleventh aspect of the present invention, in the transmission system according to the ninth aspect, the multiplexing means includes, in a plurality of frames in the block data, copyright protection information relating to the digital data. It is characterized in that certain copyright protection information is multiplexed.

[0022] In a transmission system according to a twelfth aspect of the present invention, in the transmission system according to the eleventh aspect, the copyright protection information includes a copy indicating whether or not digital data can be copied at least in a top frame where the copyright protection information is multiplexed. It is characterized by including permission information.

[0023] In a transmission system according to a thirteenth aspect of the present invention, in the transmission system according to the eleventh aspect, the copyright protection information includes copy permission information indicating whether digital data can be copied, and copy permission information indicating whether copy is permitted. The number of times of copying indicating whether copying is permitted, copy quality information indicating the quality of copying when copying is permitted, and audio processing information indicating whether to perform special audio access control. It is a feature.

According to a fourteenth aspect of the present invention, in the transmission system according to the ninth aspect, the transmission method of the digital data and the auxiliary data is such that the data is time-divided into transmission frames, The transmission of the auxiliary data is characterized in that certain bits are allocated in each transmission frame.

A transmission system according to a fifteenth aspect of the present invention is the transmission system according to the ninth aspect, wherein a transmission system of the digital data and the auxiliary data complies with a MOST system.

A transmitting apparatus according to a sixteenth aspect of the present invention inputs audio data and copyright protection information which is copyright protection information relating to the audio data, and converts eight transmission frames into one.
A transmitting device for generating a periodic signal having a period, a first multiplexing unit for multiplexing copyright protection information in synchronization with the periodic signal, and an encrypting unit for performing encryption in synchronization with the periodic signal And second multiplexing means for multiplexing periodic information indicating information on the periodic signal in synchronization with the periodic signal.

[0027] A transmission device according to a seventeenth aspect of the present invention is the transmission device according to the sixteenth aspect, characterized in that a data transmission system follows the MOST system.

[0028] A receiving apparatus according to claim 18 of the present invention inputs audio data and copyright protection information which is copyright protection information relating to the audio data, and converts eight transmission frames into one.
A transmitting device that generates a periodic signal having a period, a receiving device that receives the audio data and the copyright protection information, based on periodic information that is information on the periodic signal detected from the received data. A first separating unit that generates a periodic signal, a decoding unit that performs decoding in synchronization with the periodic signal, and a second separating unit that separates the copyright protection information in synchronization with the periodic signal. It is characterized by having.

A receiving apparatus according to a nineteenth aspect of the present invention is the receiving apparatus according to the eighteenth aspect, wherein a data transmission method follows the MOST method.

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1. Embodiments of the present invention will be described below with reference to FIGS.
FIG. 1 is a block diagram showing a configuration of a transmission system according to the present invention. In FIG. 1, 21 is a digital audio output device, 22 is a transmitting device, 23 is a receiving device, 24 is a digital audio reproducing device, 51 is a multiplexing unit, 52 is an encrypting unit,
53 is a communication means, 61 is a communication means, 62 is a decoding means,
63 is a separating means.

The digital audio output device 21 is, for example, a D
This device outputs digital audio data typified by a VD-Audio drive, and outputs digital audio data recorded on a disc and auxiliary data related to the digital audio data.

The multiplexing means 51 multiplexes the audio data output from the digital audio output device 21 with the auxiliary data, and outputs multiplexed data. The encryption unit 52 performs an encryption process for each predetermined data unit (this data unit is defined as an encryption unit) based on a conventional encryption method. For example, when the encryption unit is 8 bytes, the encryption unit 52 performs encryption processing. Digital data to be encrypted is encrypted every 8 bytes.

The communication means 53 receives the data encrypted by the encryption means 52 and sends it to the communication means 61 on the receiving device 23 side. The communication unit 61 receives the signal transmitted by the communication unit 53 of the transmission device 22 and outputs the signal to the decoding unit 62. The communication means 53 and the communication means 61
It is assumed that data is transmitted using the synchronous channel region by the MOST method described in the conventional example.

The decryption means 62 receives the data output from the communication means 61 and performs decryption processing for each encryption unit (= 8 bytes). When the transmission device 22 and the reception device 23 are not synchronized with each other, the data of the encryption unit at the time of encryption is different from the data of the encryption unit at the time of decryption, or a part of the data of the encryption unit. Is insufficient, the decryption means 62 cannot correctly decrypt the encrypted data. That is, in the decryption means 62, the data of the encryption unit selected by the encryption means 52 must be accurately synchronized and recognized. The separation means 63
It receives the data output from the decoding means 62, separates it into audio data and auxiliary data and outputs it.

The digital audio reproducing device 24 is typically a device composed of a digital amplifier and a speaker, receives the audio data and auxiliary data output from the receiving device 23, and reproduces the audio data. Output as audible sound.

FIG. 2 is an explanatory diagram of block data transmitted from transmitting apparatus 22 to receiving apparatus 23 in the first embodiment. In FIG. 2, one block is composed of frames 1 to
In each of frames 1 to 8, the first byte is header 101, the second byte is auxiliary data 102, and the third to n bytes are audio data 103. Each of the frames 1 to 8 is a fixed-period frame on the transmission path (44.1k in the MOST system).
Hz or 48 kHz), and each of the frames 1 to 8 includes time slot data used by the communication unit 53 of the transmission device 22 for data transmission.

Here, the time slot used by the communication means 53 is reserved prior to data transmission, and information about which time slot is used between the communication means 53 and the communication means 61 is shared. are doing. The time slot used by the communication means 53 is audio data 1
03, two bytes including a header 101 and auxiliary data 102 are reserved.
If the audio data 103 transmitted in 8 is 30 bytes,
A 32-byte time slot is reserved.

The frame 1 and the frame 2 in the block data are all synchronized with a sync pattern indicating a synchronization pattern.
Is a bit. The second and third bits of frame 3 are EMI
(Encryption mode indicator) The fourth bit is OE (odd even), and EMI and OE are bits defined in DTCP. As described above, sync, EMI, and OE are multiplexed by the non-encrypted area 120 that is not encrypted. The sync is data used to find the head of the block data, and the length and pattern of the sync are not limited to these, and are arbitrary.

The auxiliary data 102 includes the audio data 1
And copyright protection information indicating the copyright holder and whether or not copying is possible, and AUX data (auxiliary information) necessary for reproducing the audio data, such as the sampling frequency, quantization bit number, and channel assignment information of the audio data 103. including.

In FIG. 2, as an example, the second byte of frame 1 to frame 3 is used as the copyright protection information, and the second byte of frame 4 to frame 8 is used as the AUX data. However, the present invention is not limited to this. It is possible to transmit arbitrary data using 8 bytes.

Here, the copyright protection information of DVD-Audio is described in "DVD Specifications for Read-Only".
Part4. Audio Specification Version 1.2 ". The copyright protection information is composed of 3-byte data, and includes copy permission information (audio_copy_permission), copy count information (audio_copy_number), and copy quality information (audio_q).
uality), audio processing information (audio_transactio)
n), ISRC status information (ISRC_Status), ISR
It is composed of C number information (UPC_EAN_ISRC_number) and ISRC data information (UPC_EAN_ISRC_data).

FIG. 3 shows an example of the arrangement of each piece of copyright protection information. Copyright protection information 1 is copy control information,
It consists of 2-bit copy permission information, 3-bit copy count information, 2-bit copy quality information, and 1-bit audio processing information.

The copy permission information is information indicating whether copying is permitted or not. Specifically, 00 indicates that copying is permitted, 10 indicates that copying is permitted for the number of times indicated by the copy number information, and 11 indicates that copying is not possible.

The copy number information is information indicating how many times copying is permitted when copying is permitted. 000 is 1 time, 001 is 2 times, 010 is 4 times, 011 is 6 times, 1
00 indicates that copying is possible eight times, 101 indicates that copying is possible ten times, and 111 indicates that the number of copies is not limited.

The copy quality information is information indicating the sound quality of a copy when copying is permitted. 00 means that the number of channels is 2 or less and the sampling frequency is 48
kHz and the number of quantization bits is 16 or less, 01 indicates that the number of channels is 2 or less, and there is no limitation on the sampling frequency and the number of quantization bits, and 10 indicates It indicates that there is no limitation on the number of channels, the sampling frequency, and the number of quantization bits.

The audio processing information is a flag indicating whether or not to perform special audio access control. 0
Indicates that access control is not performed, and 1 indicates that access control is not currently reserved for the future.

The copyright protection information 2 is ISRC information (song information), and includes 3-bit ISRC status information and 5 bits.
Bit ISRC number information. The copyright protection information 3 is ISRC information, and is an 8-bit ISRC
Consists of data information.

The ISRC status information is ISRC status information used to find the position where the ISRC information has changed. 001 indicates the start position of the music, and 0
Reference numeral 10 denotes an intermediate position, that is, no change in ISRC information, and reference numeral 100 denotes an end position. The ISRC number information is 8-bit data in the ISRC data information, and indicates a number for identifying the music.

Note that copy permission information, copy number information,
Copy quality information and audio processing information are auxiliary data 1
It is desirable to be multiplexed at an earlier position of 02.
As a result, it is possible to quickly determine how to process the audio information on the receiving side.

The arrangement of such information may be any arrangement as long as it is determined between the transmitting device and the receiving device. Further, the copyright protection information is not limited to the above-described method, and any information determined in a recording medium or a broadcasting system can be used.

Next, FIG. 4 shows an example of the arrangement of AUX data. AUX1 includes a 4-bit quantization bit number 1 and a 4-bit quantization bit number 2. The quantization bit number 1 is data indicating the number of quantization bits of the channel group 1, the quantization bit number 2 is data indicating the number of quantization bits of the channel group 2, and 0 is 16 bits and 1 is 20 bits. , 3 represents 24 bits. Also, A
UX2 includes a 4-bit sampling frequency 1 and a 4-bit sampling frequency 2. Sampling frequency 1 is data indicating the sampling frequency of channel group 1, sampling frequency 2 is data indicating the sampling frequency of channel group 2, 0 is 48 kHz, 1 is 96 kHz,
2 is 192 kHz, 4 is 44.1 kHz, and 5 is 88.2
kHz and 6 represent 176 kHz. AUX3 is 5
It is composed of bit channel allocation information and a 3-bit reserved area. The channel assignment information indicates the channel assignment of the multi-channel audio data 103.

FIG. 5 is an explanatory diagram for explaining channel assignment information of multi-channel audio data in DVD-Audio (reference material is Matsushita Technic).
al Journal Vo145, No6, December 1999, Shinbo et al. "Standardization of DVD Audio". 6)
FIG. 4 is an explanatory diagram illustrating a method for transmitting digital audio data using a synchronization channel.

In FIG. 5, C is the center channel, L
And R are left and right channels, Lf and Rf are left and right front channels, Ls and Rs are left and right rear channels or surround channels, respectively, Lfe is a bass-only channel, and S is a surround channel.

As shown in FIG. 5, specifying which multi-channel audio data is to be transmitted to each of CH1 to CH6 and which channel group 1 or channel group 2 belongs, based on the value of the channel allocation information. Can be.

The audio data 103 in the block data is
According to the value of the channel assignment information, the audio samples of CH1 to CHn are arranged in order and transmitted as shown in FIG. Here, the value of n depends on the value of the channel assignment information. The audio data 103 of each CHx is composed of m audio samples according to the value of the sampling frequency of the channel group to which it belongs. For example, the frequency band of the transmission path is 48 kHz, the audio data 103 belongs to channel group 1,
If the sampling frequency 1 indicates 96 kHz, it is composed of two audio samples, and the sampling frequency 1 is 192
In the case of indicating kHz, it is composed of four audio samples. The bit number X of each audio sample is equal to the quantization bit number of the channel group to which each audio sample belongs.

FIG. 7 is a diagram for explaining the structure of audio samples at each quantization bit number. First, it is assumed that audio samples are composed in order from the upper byte (x byte) to the lower byte (x + n byte). For example, as shown in FIG. 7A, in an audio sample having a quantization bit number of 16 bits, the upper byte (H
The i-byte) is composed of 8 bits, and the lower-order bit (Lo byte) of the (x + 1) th byte is composed of 8 bits, and the audio sample is transmitted using a time slot of a total of 2 bytes.

As shown in FIG. 7 (b), in a sound sample having a quantization bit number of 20 bits, the Hi byte of the x-th byte has 8 bits, and the middle byte (Mid byte) of the x + 1-th byte has 8 bits. Four bits are configured for the Lo byte of the (x + 2) th byte, and the remaining four bits of the Lo byte are left empty. As described above, for a 20-bit audio sample, the audio sample is transmitted using a time slot of a total of 3 bytes.

As shown in FIG. 7 (c), in an audio sample having a quantization bit number of 24 bits, the Hi byte of the x-th byte is 8 bits, the Mid byte of the x + 1-th byte is 8 bits, and the x + 2 byte is the The audio sample is transmitted by using a time slot of a total of 3 bytes by configuring 8 bits in the Lo byte.

As described above, the audio samples of each quantization bit number are from the MSB (Most Significant Bit; most significant bit) first to Hi byte, Mid byte, Lo.
Transmission may be performed in the order of bytes, but is not limited to this, and LSB (Least Significant Bi
(t: least significant bit) It may be transmitted in the reverse order from the first. Further, the audio sample may be assigned to an arbitrary bit position as long as the audio sample is included in the byte. Further, in FIG. 7B, the remaining bits of the (x + 2) th byte are made blank, but by using two 20-bit samples and making up 5 bytes, there is no blank space. good.

FIG. 8 is a diagram for explaining a method of transmitting transmission data composed of frames having different periods. From FIG. 8, each cycle (48 kHz, 96 kHz, 192 kHz)
The transmission time is shown on the horizontal axis for the audio sample of FIG.

In the MOST system, when the sampling frequency of transmission data is 48 kHz, one audio sample (A1) is transmitted per frame, and the sampling frequency is 9 kHz.
At 6 kHz, two audio samples (B1, B2) are transmitted per frame, and the sampling frequency is 192 kHz.
In the case of Hz, four voice samples (C1, C2, C3, C4) are transmitted per frame.

For example, the sampling frequency is 48 kHz, 96 kHz, 192 kHz.
When the audio samples of z are mixed and transmitted, the audio samples of each channel are normalized such that the audio samples of each channel exist at the head position of the frame, and the audio samples generated earlier are transmitted in order. That is, according to the above example, the first transmitted audio samples are A1, B1, and C1, and 2
The audio sample transmitted the second time is C2, the audio sample transmitted the third time is B2 and C3, and the audio sample transmitted the fourth time is C4.

Next, another transmission system will be described with reference to FIG. FIG. 9 is a block diagram showing a configuration of another transmission system according to the present invention. In FIG. 9, 7
1 is a digital audio output device, 72 is a transmitting device, 73 is a receiving device, 74 is a digital audio reproducing device, 80 is an encryption processing unit, 81 is first multiplexing means, 82 is encryption means, 8
3 is a second multiplexing unit, 84 is a control unit, 85 is a communication unit, 90 is a decoding processing unit, 91 is a communication unit, and 92 is a first unit.
, 93 is a decoding means, 94 is a second separating means, and 95 is a control means.

The digital audio output device 71 is
5 and outputs audio data in synchronization with the clock, and outputs copyright protection information and auxiliary information related to audio as auxiliary data.

The first multiplexing means 81 inputs and multiplexes the audio data output from the digital audio output device 71, auxiliary information and copyright protection information, and outputs multiplexed data. The encryption unit 82 receives the multiplexed data from the first multiplexing unit 81, encrypts the area of the audio data 103 and the auxiliary data 102 based on the encryption key input from the control unit 84 described later, and Outputs formatted data. The second multiplexing unit 83 receives the encrypted data from the encrypting unit 82 and multiplexes the EMI and OE (header information 101) from the control unit 84. As described above, the first multiplexing unit 81, the encrypting unit 82, and the second multiplexing unit are referred to as an encryption processing unit 80. Here, the first multiplexing means 81, the encrypting means 82, and the second multiplexing means 83
Operate in synchronization with the same periodic signal. That is, each periodic signal indicates the cycle of the block, and means that the same processing is performed in the section of each periodic signal. For example, when the start point of the periodic signal is the start point of the block, the encryption unit 82 matches the start point of the periodic signal with the start point of the encryption unit. Then, the second multiplexing unit 83 multiplexes the Sync data at the start point of the periodic signal. Also, the period of the periodic signal depends on how many transmission frames one block is composed of. For example, when one block is composed of eight transmission frames, the period is synchronized with eight transmission frames. As a result, a periodic signal is generated. The periodic signal may be generated by any device, or may be supplied from outside.

The control means 84 is composed of a CPU, inputs the copyright protection information output from the digital audio output device 71, determines whether or not to perform encryption based on the information, and performs the encryption. In this case, the encryption key is output to the encryption means 82. Also, EMI and OE, which are information indicating how to perform encryption, are output to the second multiplexing means 83.

The communication means 85 outputs a clock synchronized with the transmission clock of the transmission line to the digital audio output device 71, inputs the multiplexed data from the second multiplexing means 83, and It is transmitted to the communication means 91.

The communication means 91 is provided with the digital audio reproducing device 7.
4 and outputs the clock to the communication unit 85 on the transmission device 72 side.
And transmits the encrypted data to the first separating means 92 in synchronization with the clock.

The first separating means 92 receives the data output from the communication means 91 and converts the received data into an EMI.
And OE are separated and transmitted to the control means 95, and other data is transmitted to the decoding means 93. The decryption unit 93 receives the data output from the first separation unit 92, receives the encryption key from the control unit 95, and performs a decryption process for each encryption unit. The second separation unit receives the data output from the decoding unit 93, separates the data into audio data and copyright protection information, transmits the audio data to the digital audio playback device 74, and controls the copyright protection information. To the means 95. As described above, the first separating unit 92, the decoding unit 93,
The second separating unit 94 is referred to as a decryption processing unit 90. Here, the first separating means 92, the decoding means 93, and the second separating means 94 operate in synchronization with the same periodic signal. The periodic signal is generated by looking at the Sync data of the transmission path. For example, when the start point of the periodic signal is set as the start point of the block, the decryption unit 93 matches the start point of the periodic signal with the start point of the encryption unit, as in the case of the encryption unit 82.

The control means 95 is composed of a CPU, inputs EMI and OE from the data output from the communication means 91, and decrypts the encryption key based on these information.
Output to Also, copyright protection information is input from the decrypted data, and processing such as copying of audio data is controlled based on the information.

As a result, the transmitting device 72 is
Since the data is transmitted in synchronization with the clock output from the clock 5, it is not necessary to perform the clock conversion of the audio data, the circuit configuration can be reduced, and the deterioration of the audio quality can be prevented. Can be. Further, the first multiplexing means 81, the encrypting means 82 and the second multiplexing means 8
The encryption processing unit 80 may be configured as a single semiconductor chip as the encryption processing unit 80, and the encryption processing unit 80 and the communication unit 85 may be configured as a single semiconductor chip. In addition, the first separating unit 92, the decoding unit 93, and the second separating unit 94 may be collectively configured as a single semiconductor chip as the decoding processing unit 90. The means 91 may be configured as one semiconductor chip.

Although the clocks of the transmitting device 72 and the receiving device 73 are supplied from the transmission line, the present invention is not limited to this. When any one of the devices serves as a clock source for the transmission path, the configuration is such that a clock is supplied to the transmission path.

The case where the start point of the periodic signal coincides with the start point of the block has been described. However, the present invention is not limited to this. It is needless to say that the phase relationship between the periodic signal and the block or between the periodic signal and the encryption unit may be synchronized.

As described above, according to the transmission system according to the first embodiment of the present invention, the transmission method for transmitting the channel assignment information, the sampling frequency information, and the quantization bit number information of the multi-channel audio data is determined. Thus, transmission of multi-channel audio data, which has not been conventionally performed, can be performed. Since header information is transmitted for each block when transmitting multi-channel audio data, more efficient data transmission in a smaller band can be realized as compared with a conventional transmission system that transmits header information for each frame. .

Further, according to the transmission system according to the first embodiment of the present invention, when transmitting multi-channel audio data such as DVD-Audio, multiplex transmission of copyright protection information is possible in a small band. In addition, since one block is composed of eight frames and encryption processing is performed in units of 8 bytes for each block, encryption can be performed up to the last byte regardless of the length of the audio data 103.

The priority of the transmission order of the audio samples is such that the audio samples that occur earlier in time are transmitted, so that the transmission side and the reception side wait for the required data transmission / reception timing. The amount of memory can be reduced. The transmission order may be, other than the time constraint, transmitted in the order of the channel number, or transmitted from the audio sample of the upper byte to the audio sample of the lower byte. Any order can be used as long as the order is uniquely defined.

In the first embodiment, a DVD-Audio drive is used as the digital audio output device 21. However, the present invention is not limited to this.
Drives for recording media such as AT and DVD-Video, tuners for receiving digital audio broadcasts such as digital TV broadcasts and digital radios, analog-to-digital converters for digitizing and outputting analog audio, and audio data received via the Internet A device that outputs arbitrary digital audio data, such as a PC that reproduces digital audio data, is applicable.

In the first embodiment, the receiving device 23
Is the digital audio playback device 24,
The present invention is not limited to this, and any device that uses digital sound, such as a device that records digital sound and a device that edits digital sound, can be used.

In the first embodiment, the MOST type transmission system is used. However, the present invention is not limited to this, and a transmitting apparatus and a receiving apparatus which have a time slot within a fixed period frame and perform transmission are allocated in advance. The present invention can be applied to any transmission method in which transmission is performed using the assigned time slot. Examples of such transmission schemes include:
D2B optical, etc. (Ref: "The D2B Optical
Optical Bus-an Integration platform for Car Ent
ertainment and Telematic Systems ", by Peter Mros,
Proc. Of World Congress on Intelligent Transport S
ystems Technical Sessions, Oct. 1997). Further, the transmission path is not limited to the time slot type, but may be IEEE 1394.
The present invention can be applied to any transmission path.

The AUX data is not limited to the example shown in FIG. 4, but is composed of sampling frequency information, quantization bit number information, and channel allocation information, provided that the arrangement of audio data to be transmitted is specified. , Any format is fine.
Each data of sampling frequency information, quantization bit number information, and channel assignment information may be transmitted in an arbitrary frame, and any number of bits expressing necessary information can be used, and any value can be used. It is possible to use In addition to the sampling frequency information, quantization bit number information, and channel assignment information data, it is also used to reproduce audio data to be transmitted, such as conditions for reducing the sampling frequency and quantization bit number and the presence or absence of emphasis. It can include any required data. If the sampling frequency or the number of quantization bits is a fixed value, the information is unnecessary and may be omitted.

Also, AUX data is multiplexed with audio data and transmitted via a synchronization channel, but is not limited to this. For example, when a disc is inserted, when the beginning of a song or the state of a song changes, or when a fixed AUX every hour
Data may be transmitted on an asynchronous channel or the like. Here, the asynchronous channel is an area used for transmitting data that does not require a time constraint. Examples of the asynchronous channel include a control channel and an asynchronous channel defined by MOST.
Examples of data transmitted on the control channel include, for example, operation command information (playback, fast forward, etc.) and menu information (tune list, etc.). Also, Asynchrono
Examples of data transmitted on the us channel include map data and Internet data (IP packets).

The format of the block data is
It is not limited to the one shown in FIG. In the first embodiment, one block corresponds to 8 bytes corresponding to the encryption unit of 8 bytes.
Although the frame is constituted by frames, as shown in FIG. 10, a frame having a multiple of 8 may be defined as one block. Also,
For example, one block is composed of 16 frames, and the first 8
It is also possible to use the first byte of the frame as the header and the first byte of the subsequent eight frames as the auxiliary data area. Also, for example, the encryption unit is not limited to 8 bytes, and may be n bytes other than that, and in that case, the number of frames constituting one block may be a multiple of n. The configuration of the block is not limited to these. It is sufficient that the total data amount of the encryption area included in the frame selected as the block is a multiple of the encryption unit. In this case, the same effect can be obtained by using a block having an arbitrary number of frames.

Further, for transmission of each audio sample,
Although the arrangement is as shown in FIG. 6, it is not limited to this. If the transmission device and the reception device determine the number of the audio sample of which channel and which position in the frame, the arrangement is arbitrary. Rules for arrangement may be determined in advance, may be shared prior to transmission of audio data, and an arbitrary method may be used.

[0084]

As described above, according to the transmission system of the first aspect of the present invention, a transmission apparatus for transmitting multi-channel audio data and auxiliary data necessary for reproducing the audio data, and the transmission apparatus And a receiving device for receiving the audio data and the auxiliary data transmitted from the communication device, wherein the auxiliary data includes channel assignment information of the audio data, so that multi-channel audio data can be transmitted. For example, DVD-Aud
This has the effect that audio data transmitted from the io drive can be received by a speaker device or the like and output as audio.

According to the transmission system according to the second aspect of the present invention, in the transmission system according to the first aspect, the auxiliary data further includes sampling frequency information. , It is possible to transmit multi-channel audio data.

According to the transmission system of the third aspect of the present invention, in the transmission system of the first aspect, the auxiliary data further includes quantization bit number information. Even in the case where it differs for each channel, transmission of multi-channel audio data becomes possible.

According to the transmission system of the fourth aspect of the present invention, in the transmission system of the first aspect, the channel assignment information of the audio data is DVD-Audio.
Since it is based on the o standard, when transmitting audio data by DVD-Audio, there is an effect that data transmission can be performed efficiently, for example, parameters in a recording method can be used as they are.

According to the transmission system of claim 5 of the present invention, in the transmission system of claim 1, the transmitting device includes a multiplexing unit that multiplexes auxiliary data with audio data and creates multiplexed data. The receiving device receives the multiplexed data transmitted from the transmitting device and includes a separating unit that separates the multiplexed data into audio data and auxiliary data. Has the effect that the receiving device can easily synchronize with the transmitting device.

According to the transmission system of the sixth aspect of the present invention, in the transmission system of the first aspect, the transmission device transmits the audio data having different sampling frequencies to the reception device in a time-dependent manner. Since the audio data generated earlier is multiplexed and transmitted, it is possible to reduce the amount of memory required for the transmitting and receiving sides to wait for the data transmission and reception timing required.

According to a transmission system according to claim 7 of the present invention, in the transmission system according to claim 1, the transmission method of the audio data and the auxiliary data is such that the data is time-divided into transmission frames, and For data transmission, fixed bits are allocated in each transmission frame, so efficient transmission of multi-channel audio data is performed on transmission paths using fixed-length frames, and copyright protection measures for audio data are taken. Can be applied.

According to the transmission system according to claim 8 of the present invention, in the transmission system according to claim 1, the transmission system of the audio data and the auxiliary data conforms to the MOST system. In the transmission path used, efficient transmission of multi-channel audio data can be performed, and copyright protection of the audio data can be taken.

According to the transmission system of the ninth aspect of the present invention, there is provided a transmitting apparatus for transmitting digital data and auxiliary data necessary for reproducing the digital data, and a digital data and auxiliary data transmitted from the transmitting apparatus. A transmission system comprising: a reception device for receiving data; the transmission device multiplexes auxiliary data with digital data, and creates block data including n frames, which is a multiple of a predetermined encryption unit. Multiplexing means, and encrypting means for encrypting the block data in the predetermined encryption unit to create encrypted data, wherein the receiving device decrypts the encrypted data transmitted from the transmitting device. And decoding means for separating the block data decoded by the decoding means into digital data and auxiliary data. Because, an effect that may be applied in the application of copyright protection, encryption to the last byte regardless of the length of the digital data included in each block data.

According to a transmission system according to claim 10 of the present invention, in the transmission system according to claim 9, since the predetermined encryption unit is 8 bytes and n is a multiple of 8, There is an effect that encryption can be performed up to the last byte regardless of the length of digital data included in the data.

[0094] According to the transmission system according to claim 11 of the present invention, in the transmission system according to claim 9, the multiplexing means protects a plurality of frames in the block data with respect to copyright of the digital data. Since the copyright protection information, which is information, is multiplexed, the copyright protection information can be transmitted with a smaller bandwidth.

[0095] According to the transmission system of claim 12 of the present invention, in the transmission system of claim 11, the copyright protection information includes at least whether or not digital data can be copied in a multiplexed first frame. Since the copy permission information is included, it is possible to quickly determine how to process the digital data on the receiving side.

According to the transmission system of the thirteenth aspect of the present invention, in the transmission system according to the eleventh aspect, the copyright protection information includes copy permission information indicating whether digital data can be copied and copy permission information indicating whether copy is permitted. Information about the number of times copying is permitted, copy quality information indicating the quality of copying when copying is permitted, and audio processing information indicating whether to perform special audio access control. This has the effect that the receiving side can quickly determine how to process the digital data.

According to a transmission system according to claim 14 of the present invention, in the transmission system according to claim 9, the transmission method of the digital data and the auxiliary data is such that the data is time-divided into transmission frames, For transmission of data and the auxiliary data, fixed bits are assigned in each transmission frame. Therefore, efficient transmission of multi-channel audio data is performed on a transmission path using fixed-length frames, and copyright of the audio data is transmitted. Rights protection measures.

According to a transmission system according to claim 15 of the present invention, in the transmission system according to claim 9, the transmission method of the digital data and the auxiliary data is MOS transmission.
Since the system conforms to the T method, efficient transmission of multi-channel audio data can be performed on a transmission path using fixed-length frames, and copyright protection for audio data can be taken.

A transmitting apparatus according to claim 16 of the present invention inputs audio data and copyright protection information, which is copyright protection information relating to the audio data, and converts eight transmission frames into one.
A transmitting device for generating a periodic signal having a period, a first multiplexing unit for multiplexing copyright protection information in synchronization with the periodic signal, and an encrypting unit for performing encryption in synchronization with the periodic signal And second multiplexing means for multiplexing periodic information indicating information about the periodic signal in synchronization with the periodic signal, so that it is not necessary to perform clock conversion of audio data, and the circuit configuration is reduced. In addition, it is possible to prevent voice quality from deteriorating.

In the transmission apparatus according to the seventeenth aspect of the present invention, since the data transmission scheme is based on the MOST scheme in the transmission apparatus according to the sixteenth aspect, a multi-channel audio signal is transmitted on a transmission path using a fixed-length frame. Efficient transmission of data can be performed, and copyright protection of audio data can be taken.

The receiving apparatus according to the eighteenth aspect of the present invention inputs audio data and copyright protection information which is copyright protection information relating to the audio data, and converts eight transmission frames into one.
A transmitting device that generates a periodic signal having a period, a receiving device that receives the audio data and the copyright protection information, based on periodic information that is information on the periodic signal detected from the received data. A first separating unit that generates a periodic signal, a decoding unit that performs decoding in synchronization with the periodic signal, and a second separating unit that separates the copyright protection information in synchronization with the periodic signal. Since it is provided, it is not necessary to perform clock conversion of the audio data, the circuit configuration can be reduced, and the deterioration of the audio quality can be prevented.

According to a nineteenth aspect of the present invention, in the receiving device according to the eighteenth aspect, the data transmission method is based on the MOST method. Efficient transmission of data can be performed, and copyright protection of audio data can be taken.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a transmission system according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of block data transmitted by the transmission system according to the first embodiment of the present invention.

FIG. 3 is an explanatory diagram of copyright protection information included in the block data of FIG. 2;

FIG. 4 is an explanatory diagram of AUX data included in the block data of FIG. 2;

5 is an explanatory diagram of channel assignment information in the AUX data of FIG. 4;

FIG. 6 is an explanatory diagram illustrating a data transmission method by the transmission system according to the first embodiment of the present invention.

FIG. 7 is a diagram for explaining the configuration of audio samples at each quantization bit number.

FIG. 8 is a diagram for explaining a method of transmitting transmission data composed of frames having different periods.

FIG. 9 is a block diagram showing a configuration of another transmission system of FIG. 1;

FIG. 10 is a diagram showing another example of block data transmitted by the transmission system according to the first embodiment of the present invention.

FIG. 11 is a diagram showing a data configuration of a frame included in transmission data.

FIG. 12 is an explanatory diagram illustrating a data transmission method using a conventional transmission system.

[Explanation of symbols]

 21, 71 Digital audio output device 22, 72 Transmission device 23, 73 Receiving device 24, 74 Digital audio reproduction device 51 Multiplexing means 52, 82 Encryption means 53, 61, 85, 91 Communication means 62, 93 Decoding means 63 Separating means 81 First multiplexing means 83 Second multiplexing means 84,95 Control means 92 First separating means 93 Second separating means

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Toshiaki Mori 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. F-term (reference) NN02 SS04 SS14

Claims (19)

[Claims] 1. A transmission device comprising: a transmitting device for transmitting multi-channel audio data and auxiliary data necessary for reproducing the audio data; and a receiving device for receiving the audio data and the auxiliary data transmitted from the transmitting device. A transmission system, wherein the auxiliary data includes channel assignment information of the audio data. 2. The transmission system according to claim 1, wherein the auxiliary data further includes sampling frequency information. 3. The transmission system according to claim 1, wherein the auxiliary data further includes quantization bit number information. 4. The transmission system according to claim 1, wherein the audio data channel assignment information is DVD-
A transmission system according to the Audio standard. 5. The transmission system according to claim 1, wherein the transmitting device includes multiplexing means for multiplexing auxiliary data with audio data to create multiplexed data, and the receiving device transmits from the transmitting device. A transmission system comprising: a separating unit that receives the multiplexed data and separates the multiplexed data into audio data and auxiliary data. 6. The transmission system according to claim 1, wherein, when transmitting the audio data having different sampling frequencies to the reception device, the transmission device multiplexes and transmits the audio data generated earlier in time. A transmission system characterized by that. 7. The transmission system according to claim 1, wherein, in the transmission method of the audio data and the auxiliary data, the data is time-divided into transmission frames. A transmission system, wherein a fixed number of bits are allocated. 8. The transmission system according to claim 1, wherein the transmission method of the audio data and the auxiliary data is MO transmission.
A transmission system according to the ST method. 9. A transmission system comprising: a transmitting device for transmitting digital data and auxiliary data necessary for reproducing the digital data; and a receiving device for receiving digital data and auxiliary data transmitted from the transmitting device. And a multiplexing means for multiplexing auxiliary data with digital data to create block data composed of n frames, which is a multiple of a predetermined encryption unit, and transmitting the block data to the predetermined data. Encrypting means for encrypting the data in units of encryption to create encrypted data, wherein the receiving device decrypts the encrypted data transmitted from the transmitting device, and decrypts the data by the decrypting device. A separating unit for separating the converted block data into digital data and auxiliary data. 10. The transmission system according to claim 9, wherein the predetermined encryption unit is 8 bytes. 11. The transmission system according to claim 9, wherein the multiplexing means multiplexes copyright protection information, which is copyright protection information on the digital data, into a plurality of frames in the block data. A transmission system, characterized in that: 12. The transmission system according to claim 11, wherein the copyright protection information includes at least copy permission information indicating whether or not digital data can be copied in a multiplexed first frame. Transmission system. 13. The transmission system according to claim 11, wherein the copyright protection information includes copy permission information indicating whether digital data can be copied,
Copy count information indicating how many times copying is permitted when copying is permitted, copy quality information indicating copying quality when copying is permitted, and audio processing indicating whether to perform special audio access control And transmission information. 14. The transmission system according to claim 9, wherein a transmission method of the digital data and the auxiliary data is:
A transmission system, wherein the data is time-divided into transmission frames, and a fixed bit is assigned to each of the transmission frames for transmission of the digital data and the auxiliary data. 15. The transmission system according to claim 9, wherein a transmission method of the digital data and the auxiliary data is:
A transmission system according to the MOST method. 16. A transmitting apparatus which receives audio data and copyright protection information which is copyright protection information related to the audio data, and generates a periodic signal having eight transmission frames as one period, The first to multiplex copyright protection information in synchronization with a signal
Multiplexing means, encryption means for performing encryption in synchronization with the periodic signal, and second multiplexing means for multiplexing periodic information indicating information on the periodic signal in synchronization with the periodic signal. A transmitting device characterized by the above-mentioned. 17. The transmitting device according to claim 16, wherein a data transmission method follows the MOST method. 18. A transmission apparatus which inputs audio data and copyright protection information which is copyright protection information related to the audio data, and generates a periodic signal having eight transmission frames as one cycle, and transmits the audio data and A receiving apparatus for receiving the copyright protection information, comprising: first separating means for generating a periodic signal based on periodic information that is information on the periodic signal detected from received data; A receiving device comprising: a decoding unit that performs decoding in synchronization; and a second separation unit that separates the copyright protection information in synchronization with the periodic signal. 19. The receiving apparatus according to claim 18, wherein a data transmission method follows a MOST method.