JP2000224229A - Transmission method, transmitter and receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent effect of noise onto a receiver by transmitting a signal with a comparatively high transfer rate via a serial interface with a comparatively low transfer rate. SOLUTION: A disk player 100 being a transmitter and a recorder 200 being a receiver are interconnected via two IEEE 1394 standard serial interfaces 188-1, 188-2. For example, at least one control flag among a mute flag, a copy flag by packet type and a zero flag is arranged in a header of a transfer packet at data transfer and the resulting packet is transferred and a noise generated in a D/A converter provided in the receiver is prevented in advance and a copyright management is facilitated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an audio signal,
The present invention relates to a transmission method, a transmission device, and a reception device for transmitting via a serial interface that can be connected to a plurality of devices.

[0002]

2. Description of the Related Art Conventional transmission methods using a serial interface include, for example, JP-A-7-235132 and JP-A-9-200.
162, JP-A-10-106144, JP-A-10-136286, JP-A-10-19070
No. 5 publication.

Recently, it has become necessary to transmit a large amount of data between devices, and it is desired to transmit data at a higher speed. In that case,
It is conceivable to connect and use multiple serial interfaces between devices, and when connecting and using such multiple serial interfaces, when using all of the multiple interfaces simultaneously or not There is. In addition, during use of these interfaces, there are periods during which image data is transmitted, periods during which audio data is transmitted, and periods during which transmission data is different.

In such a case, when the data receiving apparatus has a D / A converter or the like,
If the converter is a circuit not related to data processing during transmission, noise may occur in the converter.

[0005] As another problem, when such a large amount of data is transmitted, copyright management is also particularly important, and copyright management according to the packet type is required.

Therefore, the present invention has been made in view of the above problems,
An object of the present invention is to provide a transmission method, a transmission device, and a reception device for transmitting an audio signal or the like that solves these problems via a serial interface that can be connected to a plurality of devices.

[0007]

Means for Solving the Problems To achieve the above object, the present invention comprises the following means 1) to 3).
That is,

1) A transmitting apparatus and a receiving apparatus are connected via a serial interface to which a plurality of connections can be made, a predetermined header is added to a signal composed of a predetermined data stream to form a packet, and a mute flag and a packet are added to the predetermined header. A transmission method characterized in that at least one of a type-specific copy flag and a zero flag is stored and transmitted.

[0009] 2) A serial interface that can be connected to a plurality of devices, and a signal composed of a predetermined data stream with a predetermined header added thereto to make a packet. Means for storing at least one control flag and transmitting via the serial interface,
Equipped transmission device.

3) A plurality of connectable serial interfaces and a signal composed of a predetermined data stream are packetized by adding a predetermined header, and the header includes at least one of a mute flag, a copy flag for each packet type, and a zero flag. A receiving device comprising: means for receiving the signal containing two control flags via the serial interface; and means for decoding from the header contained in the header.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a first embodiment of a transmission method, a transmitting device and a receiving device according to the present invention, and FIG. 2 is a flowchart showing processing of the disc player of FIG.

In the example of FIG. 1, a disc player 100 as a transmitting device and a recording device 200 as a receiving device are provided with data transfer interfaces (I / Fs) 200a and 200a, respectively.
0b, and the data transfer I / Fs 200a and 200b are 2
IEEE1394 standard serial interface 1
88-1 and 188-2. The disc player 100 reproduces, for example, an audio signal and a still image signal recorded on a DVD audio disc, and reproduces the audio signal and the still image signal via the data transfer I / F 200a and the serial interfaces 188-1 and 188-2.
Send to 0. The recording device 200 converts the audio signal and the still image signal into serial interfaces 188-1 and 188-1.
8-2, receiving via the data transfer I / F 200b,
For example, it is recorded on a DVD-RAM disk. At this time,
One serial interface 188-1 is selectively used for reception or transmission, and the other serial interface 188-2 is used exclusively for transmission.

The operation of the disc player 100 will be described with reference to FIG. First, the data transfer I / F 200a and one serial interface 188-1 are set to the reception mode (step S1), and then the data transfer I / F 20
0a, two serial interfaces 188-1, 18
The bidirectional transmission with the recording device 200 is performed via 8-2 (step S2). Next, one of the serial interfaces 188-1 is set from the reception mode to the transmission mode (step S3), and the signal having a relatively high transfer rate is dispersed via the two serial interfaces 188-1 and 188-2. The data is transmitted to the recording device 200 (step S4). That is, in this example, the other serial interface 188-2 is always set to the transmission mode.

As a specific example of transmission data, audio data having a sampling frequency of 96 kHz is converted to 48 kHz.
The 48-kHz audio data of the two systems, which are separated and thinned, are serially interfaced 188-1 and 188-1, respectively.
A method of transmitting data via 8-2 is conceivable. As another example, 8-channel audio data is divided into 4 channels × 2.
A method of dividing into groups and transmitting each group (4 channels) via the serial interface 188-1, 188-2 is conceivable. As another example, 4
8 kHz 2-channel audio data is separated for each channel, and the serial interface 1
A method of transmitting the data via the 88-1 and 188-2 is conceivable. As still another example, since a still image signal is recorded on a DVD audio disc in addition to an audio signal, a method of transmitting the audio signal and the still image signal via the serial interfaces 188-1 and 188-2, respectively, is known. Conceivable.

In the bidirectional transmission in step S2, in order to manage the copy of the transmission data, the disc player 100 requests the recording device 200 for a copy permission password before the data transmission, and 200
Transmits a password to the disc player 100. Then, when the disc player 100 confirms the password, transmission of data is started.

The number of serial interfaces is not limited to two. For example, as shown in FIGS. 3 and 4, four serial interfaces 188-1 to 188-4 (and data transfer I / Fs 200a 'and 200b') are used. May be used.
That is, first, the interfaces 188-1 to 188-
4 is set to the reception mode (step S1).
1) Then, bidirectional transmission is performed with the recording device 200 via two lines (step S12). Next, the interface 188 in the above-mentioned reception mode is set to the transmission mode (step S13), and then the signal having a relatively high transfer rate is dispersed and recorded via the four serial interfaces 188-1 to 188-4. (Step S14).

In this case, for example, one serial interface 188-1 is selectively used for reception or transmission, and the other three serial interfaces 188-2 to 188-1 are used.
88-4 may be used exclusively for transmission. In this case, for example, 8 channel audio data is divided into 2 channels × 4, and each group (2 channel data) is serially interfaced 188-1 to 188-.
4 is conceivable. The audio signal and the still image signal are respectively converted into two serial interfaces (188-1, 188-2), (188-3, 1).
88-4).

The present invention can also be applied to an audio-compatible format of the IEC958 standard instead of the transmission system of the IEEE1394 standard. The IEC958 standard is different from the bidirectional transmission system like the IEEE1394 standard of the present embodiment, and is a transmission system in only one direction.
In the case of bidirectional transmission using a plurality of serial interfaces as in the present embodiment, it becomes easy to apply.
Further, the audio-compatible format of the IEC958 standard refers to the IEC958 standard in the IEEE1394 standard.
It may be a mode audio compatible format.
It can be applied to various modes of the EEE1394 standard.

Further, after transmitting a copy flag indicating "copy permitted" or "copy not permitted" according to the type of packet from the transmitting side to the receiving side via one serial interface, the data is transmitted to a plurality of serial ports. The data is transmitted via the interface. On the receiving side, when the copy flag of the still image packet is "copy permitted", the received data is recorded (copied) on another medium. Is not recorded (copied). If the copy flag of the audio packet is "copy permitted", the high sampling frequency is down-converted to 44.1 kHz and recorded (copied) on another medium. The received data may not be recorded (copied).

When data other than an audio signal, for example, a still image or a compressed audio signal is transmitted through a certain serial interface, a D / A for an audio signal is received on the receiving side.
The mute flag is transmitted from the transmission side to the reception side via the serial interface so that noise is not generated by the converter, and the reception side performs mute processing on the serial interface receiving the mute flag as shown in FIG. (Step S2
4 → S25). When some of the serial interfaces are not used or the data is “0”, the transmitting side transmits a zero flag to the receiving side via the serial interface, and the receiving side transmits the zero flag. As shown in FIG. 5, it may not be received from the serial interface that has received the zero flag (step S22).
→ S23). When transmitting via a plurality of serial interfaces, it is necessary to see a flag for each interface.

The above-described copy flag, mute flag, or zero flag may be transmitted in the following data arrangement. FIG. 6 shows an IE for performing the transmission.
FIG. 6A is a diagram for explaining an isochronous (Isochronous) transfer method of the EE1394 standard, and FIG. 6A shows a transport stream. The transport stream is a fixed packet of 188 bytes and includes, for example, image data, audio data, and DVD according to the DVD video standard.
A bit string of audio data according to the audio standard is arranged.

FIG. 8 shows, by way of example, the DV arranged there.
Linear PC for audio data according to D audio standard
3 shows the structure of an M-A pack (audio pack). The A pack of the linear PCM is recorded in the data area of the DVD audio disc. The A-pack of the linear PCM is composed of 2048 bytes or less, and the breakdown is composed of a 14-byte pack header and an A packet. A packet is 17,
It comprises a 9 or 14 byte packet header, a private header, and 1 to 2011 bytes of audio data (scrambled or not scrambled linear PCM data).

The private header includes: an 8-bit substream ID; a 4-bit reserved area in the ISRC; a 4-bit ISRC number in the ISRC; an 8-bit ISRC data in the ISRC; It comprises a private header length of 8 bits, a first access unit pointer of 16 bits, audio data information (ADI) of 6 bytes, and a stuffing byte of 0 to 7 bytes.

The ADI (audio data information) includes: 1-bit audio emphasis flag; 1 + 2 bit reserved area; 4-bit downmix code; and 4-bit group "1" quantization. Word length "1"
And the quantization word length “2” of the 4-bit group “2”
A 4-bit audio sampling frequency fs1 of group "1"; a 4-bit audio sampling frequency fs2 of group "2"; a 4-bit reserved area; and a 4-bit multi-channel type. , 3 bits of reserved area, 5 bits of channel allocation information, and 8 bits of dynamic range control information.

Referring again to FIG. 6, the fixed packet consisting of 188 bytes is prefixed with a time stamp called a source packet header [FIG.
(B)]. On the receiving side, a moving image or a sound is reproduced according to the time of the time stamp. These data are divided into a plurality of 48-byte data blocks [FIG. 6 (c)]. There are four division methods: 192 bytes × 1 block, 96 bytes × 2 blocks, 48 bytes × 4 blocks, and 24 bytes × 8 blocks.

Next, a plurality of data blocks are put together to form one isochronous transfer packet.
This grouping is performed with 125 μs as one cycle, sequentially grouped into a number of blocks that can be accommodated in each cycle, and an IEEE 1394 packet header described later is added to the head of the block. [FIG. 6 (d)]
Data divided into 48-byte units are 3 blocks and 2
The state in which the blocks are combined is shown.

At the time of transfer, as shown in FIG.
Arbitration is added to the beginning, followed by a cycle start packet, and further, after this cycle start packet, packets of 125 μs are repeatedly arranged at predetermined intervals and transferred.

The packet every 125 μs is composed of a packet header, a data field, and a data error detection code. The packet header includes:-16-bit data length information;-2-bit CIP (described later). Common Isochronous Pac
ket) a tag indicating the presence / absence of a header, channel assignment information for transmitting a 6-bit packet, and a transaction (tcod) indicating a 4-bit processing code.
e), 4-bit synchronization code (sy), and 32-bit packet header error detection code.

The data field is a 64-bit CIP
The CIP header is composed of a header and real data in which a data block is stored. The CIP header stores a 48-bit reserved area and 16-bit control data. "Copy permitted", "copy permitted once", "copy not permitted"
And at least one control flag of a copy flag, a mute flag, and a zero flag, and a sampling frequency 4 of audio data stored as real data.
It is used for sampling frequency information such as 4.1 kHz, 96 kHz or 192 kHz.

Next, FIG. 9 shows another example of the disc player 100, which shows a universal player capable of reproducing a DVD video disc, a DVD audio disc, and the like. In the universal player, a disc 1 such as a DVD video disc or a DVD audio disc is controlled based on the control of the control unit 14 and the operations of the operation unit 15 and the remote controller 16.
Is reproduced by the drive device 2 and demodulated by the demodulation circuit 2B. A video (V) pack reproduced from a DVD video disk and a still image pack reproduced from a DVD audio disk are composed of a still image /
The DVD is decoded by the V-pack decoder 3 and converted into a video stream. This video stream is originally scrambled by the CSS (content scrambling system) method.

When the video stream is to be displayed on an external display (not shown) via the output terminal 55 shown in FIG. 1, the video stream is decompressed and descrambled by the decompression / image conversion unit 4, and then the D stream is output. V via the / A converter 5
The pack is output as a video signal, and the still image pack is output as a sub-picture signal. On the other hand, there are two cases in which the data is transferred to the recording device 200. In the first method, the data expanded and descrambled by the expansion / image conversion unit 4 is scrambled by the scrambler 6 by the CSS method, and then the two data are transferred. Data transfer I / Fs 7-1 and 7-2IE
The data is transferred to the recording device 200 via the EE1394 or IEC958 serial interface. In the second method, a scrambled video stream decoded by a still image / V-pack decoder is transferred to a data transfer I / F.
7-1, 7-2 and IEEE1394 or IEC958
Is transferred to the recording device 200 via the serial interface.

An audio pack (A pack) reproduced from a DVD video disk or a DVD audio disk and a real time information pack (RTI pack) reproduced from a DVD audio disk
Is DVD-decoded by the A-pack / RTI-pack decoder 8 and converted into a DVD audio stream and RTI. The DVD audio stream is originally scrambled by the CSSII method.

When outputting the audio signal through an external speaker through the output terminal 55, the audio stream is subjected to PCM conversion, descrambling, etc.
The signal is converted into a CM signal and then output via the D / A converter 10. When the RTI is displayed on an external display (not shown), the RTI is converted into character information by the display signal generator 11 and output. On the other hand, the recording device 2
00, there are two cases as in the case of the video. In the first method, the PCM converted and descrambled by the PCM conversion / audio signal processing unit 9 are used.
The M signal is scrambled by the CSS II system by the scrambler 12, and then the two data transfer I / Fs 13-1,
13-2 and transferred to the recording device 200 via the serial interface of IEEE1394 or IEC958.

In the second method, the A-pack / RTI-pack decoder 8 decodes the D
VD audio stream is data transfer I / F13-
1, 13-2 and the IEEE 1394 or IEC958 serial interface.

FIG. 10 shows another example of the recording apparatus 200, which shows an apparatus for recording data transferred by the universal player 100 shown in FIG. 9 on a DVD-RAM disc.
8 or the data transferred via the IEEE 1394 serial interface is a data transfer I / F 21-1,
21-2. Note that the data transfer I / F
21-1 and 21-2, the DVD formatting unit 22 and the descrambler 27, the universal player 100
A video mode or an audio mode is set by the control unit 30 based on the actual data transferred by the control unit. Then, the scrambled data is transferred to the medium 26, for example, DV.
When recording the data on the D-RAM disk 26, the received data is formatted by the DVD format unit 22 according to the DVD video standard or the DVD audio standard, and then sent to the modulation circuit 23 as it is or temporarily stored in the buffer recording unit 24. After being recorded, it is sent to the modulation circuit 23. In the modulation circuit 23, the data is modulated by a method corresponding to the medium, and then the modulated data is sent to the drive device 25,
For example, it is recorded on a DVD-RAM disk 26.

On the other hand, the descrambled data is
-When recording on the RAM disk 26, the descrambler 27
The audio data is descrambled by the CSS method and descrambled by the SS method. Next, the video stream is compression-encoded by the DVD video encoder 28 and sent to the DVD formatting unit 22, and the still image data is compression-encoded by the compression encoder 29 and sent to the DVD formatting unit 22. Further, the audio data, the copyright information and / or the real-time text information are sent to the DVD formatting unit 22 as they are, and the control information is sent to the control unit 30.

In each of the above embodiments, the receiving device is described as a recording device. However, the present invention is not limited to this, and data may be exchanged between reproducing devices. In addition, the recording system and the reproducing system may be integrated. It may be a recording / reproducing device. As a configuration of the recording / reproducing apparatus, for example, the recording system is configured as shown in FIG.
The demodulation circuit 2B shown in FIG.
A still image V-pack decoder 3, a decompression / image conversion unit 4, and a D / A conversion unit 5 are provided in one of the systems subsequent to the demodulation circuit 2B.
A video reproduction system consisting of
/ RII pack decoder 8, PCM conversion / audio signal processing unit 9, D / A conversion unit 10, and display signal generation unit 11
And the like. Also in this case, by transferring a header including at least one of the above-mentioned copy flag, mute flag, and zero control flag at the time of transfer from the transmission device, noise generated in the D / A converter 10 and the like can be prevented beforehand. And can easily manage copyrights.

The interface in the above embodiment is an interface that can be connected to a plurality of interfaces, and has been described with a configuration in which a plurality of interfaces are connected in consideration of transferring a large amount of data at a higher speed. If high-speed transfer of a large amount of data is not desired, one IEEE 1394 standard interface capable of bidirectional transfer may be used.

[0039]

As described above, according to the present invention, since data transmission is performed using a serial interface to which a plurality of connections can be made, a large amount of data can be transferred at a higher speed, and a control flag is simultaneously transmitted. Control of the interface not used at the time of transfer and control of the circuit operation on the receiving device side.Also, it is possible to know whether or not data copying is possible, and to prevent the influence of noise on the receiving device side. This makes it possible to prevent copyright management and facilitate copyright management.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a first embodiment of a transmission method, a transmission device, and a reception device according to the present invention.

FIG. 2 is a flowchart showing a process of the disc player of FIG. 1;

FIG. 3 is a block diagram illustrating a transmission method, a transmission device, and a reception device according to a second embodiment.

FIG. 4 is a flowchart showing processing of the disc player of FIG. 3;

FIG. 5 is a flowchart showing a process of the recording apparatus of FIGS. 1 and 3;

FIG. 6 is a diagram for explaining an isochronous transfer method in the IEEE 1394 standard.

FIG. 7 is a detailed diagram of a data array at the time of transfer.

FIG. 8 is a data structure diagram of an A pack of linear PCM of audio data according to the DVD audio standard.

FIG. 9 is a block diagram showing another example of the disc player of FIG. 1;

FIG. 10 is a block diagram illustrating another example of the recording apparatus of FIG. 1;

[Explanation of symbols]

Reference Signs List 100 Disc player (transmitting device) 188-1 to 188-4 Serial interface 200a, 200b Data transfer interface (transmitting means) 200a ', 200b' Data transfer interface (receiving means) 200 Recording device (receiving device)

Claims (3)

[Claims] 1. A transmitting device and a receiving device are connected via a serial interface which can be connected to a plurality of devices, a predetermined header is added to a signal composed of a predetermined data stream to form a packet, and a mute flag and a packet are added to the predetermined header. A transmission method characterized in that at least one of a type-specific copy flag and a zero flag is stored and transmitted. 2. A serial interface that can be connected to a plurality of devices, and a packet formed by adding a predetermined header to a signal composed of a predetermined data stream, and the predetermined header includes a mute flag, a copy flag for each packet type, and a zero flag. Means for storing at least one control flag and transmitting the control flag via the serial interface. 3. A serial interface that can be connected to a plurality of devices, a signal comprising a predetermined data stream, a predetermined header is added to the signal, and the signal is packetized. Means for receiving the signal containing the two control flags via the serial interface,
Means for decoding from the header stored in the header.