JP4053705B2 - Audio transmission apparatus and audio transmission method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus and method for transmitting an audio signal, and more particularly to an audio transmission apparatus and an audio transmission method for transmitting copy management information to a compressed digital audio signal.
[0002]
[Prior art]
In MPEG2-TS, CGMS (Copy Generation Management System), which is a descriptor determined for copyright information of a video signal, is used as a copy control descriptor, and is generally inserted in broadcasting etc. in each country. It has been decided.
[0003]
On the other hand, in digital transmission of an unencoded audio signal alone, SCMS (Serial Copy Management System), which is an identifier of copyright information for the audio signal, is adopted and adopted in IEC60958.
[0004]
Some audio content recorded on broadcasts and media requires copyright protection, and measures must be taken to prevent unauthorized copying. Video content / video signal + In the case of an audio signal, CGMS is inserted, and in the case of only an audio signal, SCMS is inserted.
[0005]
At present, since the audio signal transmitted by an audio provider such as the record industry association of America (RIAA), which is a record-related industry organization in the United States, is encoded, the data does not describe SCMS. It is not permitted to transmit to the digital interface as it is.
[0006]
Also, according to the rules of a license institution of DTCP (Digital Transmission Copy Protection) which is one of IEEE 1394 copy protection standards, transmission of an encoded audio signal is not permitted.
[0007]
[Problems to be solved by the invention]
Thus, in the conventional audio transmission apparatus and audio transmission method, transmission of only the encoded audio signal to the digital interface is not permitted because CGMS and SCMS are not described. For this reason, there is a problem in that only the MPEG2-TS audio signal cannot be transmitted to a receiver that wants to receive only the MPEG2-TS audio signal.
[0008]
In order to solve the above problems, an object of the present invention is to provide an audio transmission apparatus and an audio transmission method capable of transmitting an MPEG2-TS audio signal to a receiver that wants to receive the MPEG2-TS audio signal.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, according to the present invention, there is provided an audio transmission apparatus for transmitting data to a digital interface that does not permit transmission of only compressed audio data, the audio data together with the compressed audio data. first copy control descriptor (e.g., SCM S) against the stream (e.g., SI) that includes an input that is input in accordance with the content of the first copy control descriptor, the first Copy control descriptor conversion means for converting a copy control descriptor into a second copy control descriptor (for example, CGMS), and a stream (for example, PMT) including the second copy control descriptor (for example, CGMS) means for generating the image data to be the audio data and multiplexing the image data generating means to generate separately from the audio data, the sound voice data A packet (eg, PMT) including first packetizing means for packetizing, second packetizing means for packetizing the image data, and the second copy control descriptor (eg, CGMS). a third packetizing unit that reduction, to generate a multiplexed packets each packet obtained each Ri by said first to third packetization means and multiplexed so as to correspond to the format of the digital interface, wherein copy control information corresponding to the format that is generated based on the second copy control descriptor (e.g., EMI) that was and output means for outputting to the pressure to the digital interface with the header of the multiplexed packet An audio transmission device is provided.
[0010]
Further, the present invention provides a voice transmission method to a digital interface that does not allow transmission of only the compressed audio data performs data transmission, the first copy control descriptor against this voice data together with the compressed audio data children (e.g., SCM S) copy stream (e.g., SI) the steps which are entered by the copy control descriptor conversion means, in accordance with the contents of the first copy control descriptor, the first containing the the control descriptor second copy control descriptor (e.g., CGMS) and generating and converting the said second copy control descriptor (e.g., CGMS) a stream (e.g., PMT) including the Paquet image data to be the audio data and multiplexing, the method comprising generate separately from the voice data, the first packetization means, the sound voice data A stream including the second copy control descriptor (for example, CGMS) by the third packetizing means, and the third packetizing means. For example, PMT) is packetized, and output means generates a multiplexed packet in which each packet obtained by the first to third packetizing means is multiplexed in accordance with the format of the digital interface. while, a step of outputting the copy control information of the second copy control descriptor corresponding to the format generated based on (e.g., EMI) and then pressurized with a header of the multiplexed packet to the digital interface An audio transmission method is provided.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
Hereinafter, a first embodiment of the present invention will be described in detail with reference to FIGS.
[0012]
In the present embodiment, as shown in FIG. 3, an audio signal transmitted by digital broadcasting is received by the digital broadcast receiver 31, and the MPEG2-TS encoded audio signal of a predetermined audio program is directly decoded without decoding. The data is output to DVHS (digital VHS) 32 via a network.
[0013]
In the digital broadcast receiver 31 of FIG. 3, the TS & demultiplex processing circuit 11, the video signal generation circuit 12, the PMT generation circuit 13, and the IEEE 1394 processing circuit 14 shown in FIG. 1 are provided.
[0014]
In FIG. 1, a video signal generation circuit 12 generates, for example, background video (hereinafter referred to as BGV), and performs 1394 processing on a BGV data, that is, a video signal transport stream (hereinafter referred to as TS). Output to the circuit 14.
[0015]
The TS & demultiplex processing circuit 11 receives the TS including the audio program selected by the digital broadcast receiver 31 and demultiplexes the audio program packet selected from the input TS. The TS of the audio program only is output to the IEEE 1394 processing circuit 14. If this TS is transmitted in 1394, it becomes as shown in FIG. It is currently not permitted by audio companies to transmit 1394 audio-only MPEG2-TS.
[0016]
Furthermore, the TS & demultiplex processing circuit 11 generates the above-described BGV (or BGV + audio program) copy control information based on the audio program copy management information (CGMS or SCMS) selected in advance, and generates a PMT generation circuit. 13 to output.
[0017]
If this is inserted into the SI (service information) of the audio program as the first copy management information, it is sent to the PMT generation circuit 13 and again as the second copy management information for BGV + audio, the PMT generation circuit 13 And inserted into the PMT stream.
[0018]
For example, the first copy management information (CGMS or SCMS) previously assigned to the program is CGMS copy-free when copy free, CGMS copy once when copying is permitted n times, and CGMS when copy prohibited. To copy prohibition.
[0019]
Usually, in the 1394 output stream, the CGMS is inserted into a PMT (Program Map Table) for sending auxiliary information of data to be transmitted. In the present invention, the PMT generation circuit 13 creates a PMT in which the second copy management information (CGMS) of BGV (or BGV + audio program) is inserted, and generates IEEE 1394 processing circuit 14 and 1394 header copy control information. Output to the circuit 15.
[0020]
The 1394 header copy control information generation circuit 15 generates EMI (Encryption Mode Indicator), which is copy control information to be inserted into the 1394 Isochronous packet header, from the input second copy management information of the PMT, and outputs it to the IEEE 1394 processing circuit 14. .
[0021]
The IEEE 1394 processing circuit 14 is stipulated by IEC61883-4 that the TS of the BGV data from the input video signal generation circuit 12, the PMT from the TS & demultiplex processing circuit 11, and the TS of the selected audio program. Each time stamp is added according to the method, and EMI is added to the header of the packet, which is sent to the IEEE 1394 transmission path. At this time, the TS from the video signal generation circuit 12 and the TS and PMT from the TS & demultiplex processing circuit 11 are designated as the same 1394 Isochronous channel and sent to the IEEE 1394 transmission path.
[0022]
In the IEEE 1394 processing circuit 14, when only MPEG2-TS and PMT of only the audio signal from the TS & demultiplex processing circuit 11 are transmitted in 1394, the signal is as shown in FIG. Thus, since the consent of the audio provider has not been obtained, the BGV data from the video signal generation circuit 12 is always multiplexed and the signal as shown in FIG. By transmitting the second copy descriptor (CGMS) based on the signal and performing EMI processing based on the second copy descriptor (CGMS), it is possible to prevent a violation of the regulations.
[0023]
Whether or not to record the encoded audio signal sent from the digital broadcast receiver 31 via the 1394 transmission path on the magnetic tape of the DVHS 32 is controlled based on CGMS.
[0024]
In the first embodiment, the transmission is performed from a digital broadcast receiver to DVHS (digital VHS). However, the transmission side is not limited to this, and any device that reproduces audio content such as a DVD can be applied. is there.
[0025]
The video signal generation circuit 12 detects the program name of the audio program and the title of the song included in the SI (service information) originally included in the content as the BGV, and generates image information of the characters. You may do it. In this way, it is possible to know from which program the program was obtained or simply by displaying the title of the song on the DVHS side.
[0026]
As described above, it is possible to provide an audio transmission apparatus and an audio transmission method capable of transmitting an MPEG2-TS audio signal to a receiver that wants to receive the MPEG2-TS audio signal.
[0027]
(Second Embodiment)
Next, a second embodiment of the present invention will be described in detail with reference to FIGS.
[0028]
In the present embodiment, as shown in FIG. 5, the MPEG2-TS encoded audio signal reproduced from the DVD audio 41 is directly output to the digital television 52, the digital amplifier 53, or the recording / reproducing DVD 54 via the IEEE 1394 network without decoding. To do.
[0029]
5 includes a video signal generation circuit 41, a DVD audio signal processing circuit 42, an MPEG2-TS circuit 43, a second copy control descriptor conversion circuit 45, a PMT generation circuit 46, An IEEE 1394 processing circuit 47 and a second copy control descriptor conversion circuit 45 are provided.
[0030]
In FIG. 4, the video signal generation circuit 41 generates BGV and outputs TS of BGV data to the IEEE 1394 processing circuit 47.
[0031]
The DVD audio signal processing circuit 42 sends the reproduction data reproduced from the reading circuit such as a DVD audio pickup to the MPEG2-TS circuit 43, and the detected second copy of the SCMS as the first copy control descriptor. The data is output to the second copy control descriptor conversion circuit 45 that converts the control descriptor. The second copy control descriptor conversion circuit 45 converts the CGMS according to the SCMS and outputs it to the PMT generation circuit 46.
[0032]
The PMT generation circuit 46 generates a PMT signal, which is an information table relating to the 1394 output signal including CGMS, and outputs the PMT signal to the MPEG2-TS processing circuit 43 and the copy control information generation circuit 48 of the 1394 header. For example, CGMS copy-free when SCMS copy-free, CGMS copy-prohibited when SCMS copy is prohibited, CGMS copy-once (copy allowed only once) when SCMS copy is allowed n times, and PMT generated Output to the circuit 46.
[0033]
Output to the MPEG2-TS circuit 43. The MPEG2-TS processing circuit 43 performs MPEG2-TS processing and outputs it to the IEEE 1394 processing circuit 47.
[0034]
The 1394 header copy control information generation circuit 48 generates 1394 header copy control information (EMI) from the input PMT, and outputs it to the IEEE 1394 processing circuit 47.
[0035]
The IEEE 1394 processing circuit 47 adds a time stamp to the signals input from the video signal generation circuit 41 and the MPEG2-TS processing circuit 43 by the method prescribed in IEC61883-4, and performs copy control of the 1394 header. Copy control information from the information generation circuit 48 is inserted, and a signal shown in FIG. 3C is output to the digital television 52 or the digital amplifier 53. At this time, the TS from the video signal generation circuit 41 and the TS and PMT from the MPEG2-TS processing circuit 43 are designated as the same 1394 Isochronous channel and sent to the IEEE 1394 transmission path.
[0036]
In the case where only the TS (audio signal and TS of the PMT) from the MPEG2-TS processing circuit 43 is transmitted in 1394 as defined in IEC61883-4, the IEEE 1394 processing circuit 47 is shown in FIG. Since it becomes a street signal, it is not approved by the audio provider. Therefore, the BGV data from the video signal generation circuit 41 is always multiplexed and the signal as shown in FIG. 2C is sent to the IEEE 1394 network. Preventing violations.
[0037]
Then, the signal sent from the DVD audio 51 via the 1394 transmission path is such that the encoded audio signal is copy-controlled based on the second copy control descriptor (CGMS), the digital television 52 or the digital amplifier 53, and the recording / playback. Processed on DVD 54.
[0038]
The BGV generated from the video signal generation circuit 41 in FIG. 4 may be a fixed image pattern regardless of the audio information to be output, or the OSD (on-screen) in the sub-picture data recorded in the disk data. Data: On Screen Data) Image information (OSD) may be created from data and character information and output as BGV.
[0039]
As described above, it is possible to provide an audio transmission apparatus and an audio transmission method capable of transmitting an MPEG2-TS audio signal to a receiver that wants to receive the MPEG2-TS audio signal.
[0040]
The digital amplifier 53 receives a still image TS, but does not have a display process internally, so only an audio signal is processed after all.
[0041]
The following is common to the first and second embodiments.
[0042]
In the present embodiment, the BGV data is used. However, the present invention is not limited to this, and a normal moving picture video signal or a blue back screen may be used. For example, it is not preferable to insert one still image only at the beginning of an audio program because it is close to sending only an encoded audio signal to the IEEE 1394 digital interface.
[0043]
IEEE 1394 standardizes the insertion of 2-bit copy control information based on the value of CGMS in the MPEG2-TS PMT as the EMI (Encryption Mode Indicator) value of the 1394 Isochronous Packet header. Is used. For example, when a digital broadcast receiver records the contents of a service on a digital recorder such as DVHS through a digital interface, copy control is performed by EMI based on CGMS in the DTCP method.
[0044]
This is because when an audio signal is output together with a video signal, an audio provider such as RIAA recognizes that audio copy control may be performed by CGMS of the video signal.
[0045]
【The invention's effect】
As described above, according to the present invention, it is possible to transmit an MPEG2-TS audio signal to a receiver that wants to receive only MPEG2-TS audio.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining an audio transmission device according to a first embodiment;
FIG. 2 is a diagram for explaining a 1394 transmission signal.
FIG. 3 is a diagram for explaining a configuration example including a voice transmission device according to the first embodiment;
FIG. 4 is a diagram for explaining a voice transmission device according to a second embodiment;
FIG. 5 is a diagram for explaining a configuration example including a voice transmission device according to a second embodiment;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 ... TS & demultiplex processing circuit, 12 ... Video signal generation circuit, 13 ... PMT generation circuit, 14 ... IEEE1394 processing circuit

Claims (6)

An audio transmission device that transmits data to a digital interface that does not allow transmission of only compressed audio data,
An input end stream is input includes a first copy control descriptor against this voice data together with the compressed audio data,
Copy control descriptor conversion means for converting the first copy control descriptor into a second copy control descriptor in accordance with the contents of the first copy control descriptor ;
Means for generating a stream including said second copy control descriptor;
Image data to be the audio data and multiplexing the image data generating means to generate separately from the voice data,
A first packetizing means for packetizing the sound voice data,
Second packetizing means for packetizing the image data;
Third packetizing means for packetizing a stream including the second copy control descriptor;
To generate a multiplexed packet multiplexed in correspondence with each packet obtained each Ri by said first to third packet means the format of the digital interface, based on the second copy control descriptor audio transmission apparatus characterized by comprising an output means for outputting to the digital interface the generated copy control information corresponding to the format appends a header of the multiplexed packet.   The copy control descriptor converting means is a second unit that permits copy free when the first copy control descriptor is copy free, prohibits copy when the copy is prohibited, and permits one copy when copy n (n is a natural number) is permitted. The voice transmission device according to claim 1, wherein the voice transmission device is converted into a copy control descriptor.   2. The audio transmission apparatus according to claim 1, wherein the output unit outputs the image data once in a predetermined period.   2. The audio transmission apparatus according to claim 1, wherein the image data generation means is a means for generating a still image regardless of audio to be transmitted in an audio transmission apparatus having means for outputting to the digital interface. .   2. The audio transmission apparatus according to claim 1, wherein the image data generation means is an image generation means for displaying characters or displaying an image based on information inserted in content service information. An audio transmission method for transmitting data to a digital interface that does not allow transmission of only compressed audio data,
The method comprising stream are entered that contains first copy control descriptor against this voice data together with the compressed audio data,
A step of converting the first copy control descriptor into a second copy control descriptor according to the contents of the first copy control descriptor by a copy control descriptor conversion means;
Generating a stream including the second copy control descriptor;
Image data to be the audio data and multiplexing, the method comprising generate separately from the voice data,
The first packetization means, the steps of packetizing the sound voice data,
Packetizing the image data by a second packetizing means;
Packetizing a stream including the second copy control descriptor by third packetizing means;
The output unit generates a multiplexed packet in which each packet obtained by the first to third packetizing units is multiplexed in correspondence with the format of the digital interface, and the second copy control descriptor speech transmission method is characterized in that a step of outputting to the digital interface to be pressurized with the copy control information corresponding to the format that is generated based on a header of the multiplexed packet.

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