JP2003009125A - Method and apparatus for delivering contents information as well as method and apparatus for receiving contents information - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize an apparatus for delivering contents information capable of transmitting contents information of a high quality level real time, by using a communication network which cannot sufficiently obtain a transmission speed and sufficiently protecting a copyright of the content information, and to provide an apparatus for receiving the content information. SOLUTION: A method for delivering contents information comprises the steps of previously dividing the contents information of a content delivering person side into two by a code divider 12, recording one coding signal in a medium 30 by a signal recorder 18, transmitting other coding signal by a signal transmitter 16 in response to a request from a user side to a content reproducer 40 via a contents transmission line 20, and processing to build up the signal from the signal reproduced from the medium 30 in the reproducer 40 and the signal transmitted via the line 20 by a code assembling unit 48 to obtain the coded signal of a high quality level protected by the copyright.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording medium in which a part of content is recorded and real-time transmission of digital content by transmitting another part of the content using a digital communication network, A method of delivering high-quality content over a transmission path with a limited transmission speed, and a method of delivering content information with enhanced copyright protection related to the content, a method of receiving content information, and content equipped with those functions. The present invention relates to an information delivery device and a content information receiving device.

[0002]

2. Description of the Related Art Conventionally, television broadcasting, FM broadcasting, and digital broadcasting have been used as transmission media as means for transmitting content information such as high-quality video and music signals in the home. C is a medium for recording content information on a medium and delivering the medium.
D, DVD, etc. are generally used.

Recording media such as CDs and DVDs, and large-capacity storage media such as recorded VTR tapes can be auditioned or watched by the program software when desired at the convenience of the viewer. Has been done.

Furthermore, recently, due to the rapid spread of personal computers and the Internet, it has become possible to obtain various kinds of information quickly and easily in ordinary households.
The distribution of video and music information using a communication network such as DSL (Digital Subscriber Line) is becoming widespread, and the transmission of video and music signals using the communication network, and the transmission and reproduction of content performed through these communication networks. Has become possible.

[0005]

However, the optical fiber, ADSL, which is becoming available for general household use.
(Asynmetric Digital Subscriber Line), CATV,
In order to perform transmission and reproduction of high-quality video signals and music signals using high-speed nets such as wireless communication, a high-speed communication net that secures at least a transmission rate that transmits information of that quality is required. Although these high-speed nets are currently being developed, the transmission rate available to the user also changes depending on the usage environment of the high-speed net, and it is always necessary to secure the high-speed net with the transmission rate desired by the user. You are in a difficult situation.

In such a situation, reproduction of a high-quality video signal and music signal at home is performed using a storage medium such as a DVD or a CD, but a high-quality video signal using the storage medium. , And music signal delivery media have problems with illegal copying.

In the illegal copying, when the content to be copied is recorded as an analog signal, the image quality is deteriorated and the noise is increased depending on the number of times of copying, and the quality of the content is deteriorated. Although not a problem, in the case of digitally recorded content information in recent years, there is no deterioration of the content according to the number of copies, and illegal copying of content information without such deterioration protects the rights of the content copyright holder. The situation is unfavorable.

In order to solve such a copyright protection problem, a method of prohibiting copying of a recording medium without permission information indicating that copying is permitted has been proposed, and a function related to the copying inhibition is provided. Although the recording device has been introduced to the market, the recording device does not have the illegal copying countermeasure function that has been supplied to the market in the past, and the device that has the illegal copying countermeasure function while maintaining the compatibility with the recording medium. In fact, there is no preferable method to introduce the product into the market, and effective countermeasures against illegal copying cannot be taken.

However, in order to implement countermeasures against illegal copying, it is effective to transmit and reproduce the information signal using the above-mentioned high speed net, and the copyright holder and the content provider can secure the distribution fee. However, since it is difficult to secure the above-mentioned communication speed for online distribution, it is not possible to reliably transmit a high-quality information signal.

A method of transmitting a high-quality information signal at the limited communication speed is such that the information signal is transmitted to the user side at a low speed, and the user side transmits the transmitted information signal to a recording medium such as a hard disk. There is a method of reproducing a high-quality information signal by storing it in a real time and reproducing the high-quality information signal accumulated for a long time. A receiving method such as receiving and receiving is not convenient and is not preferable.

To improve the convenience, for example, by providing a high-speed communication network using an optical cable and constructing a communication base with a higher communication speed, it becomes possible to transmit and reproduce high-quality images and music in real time. The maintenance of a high-speed communication network requires time and various expenses, and there is a problem that the large-capacity communication cost when the infrastructure is maintained is expected to be high.

Therefore, according to the present invention, an information encoded signal is obtained by encoding an information signal such as a high-quality video signal and a music signal, and the obtained information signal is converted into two signals according to the purpose, for example, real time. An information signal for transmission related to reproduction,
It is divided into a recording information signal related to a signal having a relatively large amount of information necessary for reproduction as high-quality information, and the recording information signal is recorded in a recording medium in advance and delivered to the user. The information signal for transmission is supplied to the user via the communication network in response to the request for reproduction of the information signal from the user, and the user transmits the information signal for recording recorded on the recording medium and the communication network. An information coded signal is obtained by combining it with a transmission information signal, and the obtained information coded signal is decoded to obtain a high quality video signal or music signal, and the high quality video signal is obtained. , And even when the music signal is transmitted using a communication network that does not provide a sufficient transmission speed, the high-quality video signal or music signal is reproduced in real time, and the high-quality signal is reproduced. (EN) A method of delivering content information, a method of receiving content information, and a content information delivery apparatus and a configuration of the content information receiving apparatus, which are provided with such functions, so that copyright protection for a video signal or a music signal is performed. It is the one we are trying to provide.

[0013]

The present invention comprises the following means 1) to 9) in order to solve the above problems. That is,

1) A content information delivery method for delivering content information to a user as encoded content information by a content deliverer, wherein a predetermined portion of the content information at the content deliverer is encoded in advance. A first step (18) of recording the obtained first encoded signal portion on a medium and transporting the recorded medium to the user, and a predetermined portion of the content information in response to a request from the user side. A second encoded signal portion obtained by encoding a content portion that does not include the second portion is transmitted to the user via a transmission medium having a communication path established between the content distributor side and the user side. A method of delivering content information, comprising at least the step (16).

2) Both the first coded signal part and the second coded signal part are coded signal parts that have been compression coded, or coded signals that have been converted into digital signals. The method for delivering content information according to item 1), which is a part.

3) The first coded signal portion is converted into a digital signal with a bit number of 4 or more at each sampling time, and is composed of upper and lower signal portions, and the upper signal portion is plural. Is a signal portion represented by a plurality of bits in the upper group of the digital content signal represented by the number of bits, and the lower signal portion is represented by a plurality of bits in the lower group of the digital content signal. The method of delivering content information according to item 1), characterized in that it is a signal portion.

4) The first coded signal portion is a compression-coded video signal composed of an intra-frame coded signal portion and an inter-frame predictive coded signal portion,
The content information delivery method according to 1), wherein the intra-frame encoded signal portion or the inter-frame predictive encoded signal portion is either one of the signal portions.

5) The first coded signal portion is a signal portion relating to a voice signal which is compression-coded by combining signal portions based on a plurality of compression methods, and when the signal portion is decoded The method of delivering content information according to item 1), characterized in that the signal information is one of a signal portion from which a part of content information is obtained or a signal portion from which almost no content information is obtained. .

6) A first encoded signal portion obtained by previously encoding a predetermined portion of the content information at the content distributor is recorded and supplied on a recording medium and does not include the predetermined portion of the content information. A second encoded signal portion obtained by encoding the content portion is supplied via a transmission medium, and the content information is obtained from the supplied signals of the first encoded signal portion and the second encoded signal portion. A method of receiving content information, comprising: reproducing the recording medium to obtain the first encoded signal portion, and receiving a signal supplied by the transmission medium to obtain the second encoded signal portion. First step (41, 4
5), a second step (47) of combining the first coded signal portion and the second coded signal portion to obtain a coded signal related to the digital content information, and a second step (47) thereof. A third step (48) of decoding the coded signal obtained in the step to obtain the content information, the receiving method of the content information.

7) A content information delivery device for delivering content information to a user as encoded content information by a content deliverer, wherein a predetermined portion of the content information provided to the content deliverer is encoded in advance. Recording signal generating means (18) for supplying the obtained first encoded signal portion to the medium recorder as a signal for recording on the medium, and content not including a predetermined portion of the content information in response to a request from the user side. Signal transmission means for transmitting a second encoded signal portion obtained by encoding the portion to the user side via a transmission medium in which a communication path is established between the content distributor side and the user side. (16) A content information delivery apparatus comprising at least the following:

8) A first encoded signal portion obtained by previously encoding a predetermined portion of content information existing in a content distributor is recorded and supplied on a recording medium and does not include the predetermined portion of the content information. A second encoded signal portion obtained by encoding the content portion is supplied via a transmission medium, and the content information is obtained from the supplied signals of the first encoded signal portion and the second encoded signal portion. A content information receiving apparatus for reproducing the signal recorded on the recording medium to obtain the first encoded signal portion, and a signal supplied via the transmission medium. A signal receiving means (41) for receiving the second coded signal portion to receive the content information by combining the first coded signal portion and the second coded signal portion. And a decoding means (48) for decoding the coded signal obtained by the code assembling means to obtain the content information. A content information receiving device characterized by:

9) In the reproduction of the recording medium by the signal reproducing means, instead of reproducing the recording medium, the first encoded signal portion previously supplied from the content distributor via the transmission medium is temporarily used. 9. The content information receiving apparatus according to claim 8), wherein the content information receiving apparatus is configured to record in a storage medium and reproduce the recorded temporary storage medium to obtain the first encoded signal portion.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a content information delivery method, a content information receiving method, a content information delivery apparatus, and a content information receiving apparatus according to the present invention will be described below with reference to preferred embodiments. FIG. 1 is a schematic block diagram of a content information delivery system including a content information delivery apparatus including the content information delivery method and a content information receiving apparatus including the content information receiving method. Will be outlined.

The content information delivery system shown in the figure has an encoding unit 11, a code division unit 12, a division information unit 13, a personal information unit 14, a digital modulation unit 15, a signal transmission unit 16, a digital modulation unit 17, and a signal recording. The content information delivery device 10 including the unit 18, the content transmission path 20, the content recording medium 30, the signal reception unit 41, the digital demodulation unit 42, the personal information acquisition unit 43, the encryption key acquisition unit 44, the signal reproduction unit 45, A digital demodulation unit 46, a code assembly unit 47,
And a content information receiving device 40 including a decoding unit 48
And a display unit 50.

Next, the operation of the content information delivery system having such a configuration will be outlined. First, digital content such as a video signal to be delivered to the user is supplied to the encoding unit 11.

In the encoding unit 11, the supplied digital contents are processed by, for example, MPEG (moving picture exper).
ts group) 2 to obtain a coded signal according to the international coding standard, and the obtained coded signal is the code division unit 12
Is supplied to.

In the code division unit 12, the division information unit 13
The coded signal supplied is divided into two parts such as a division method set by, for example, a basic portion related to the definition of the video signal and a functional portion related to the performance such as motion of the image.

The coded signal relating to the basic part of the divided coded signal is supplied to the digital modulation section 17 and subjected to digital modulation for recording on the content recording medium 30. The signal is recorded on the content recording medium 30 via the signal recording unit 18.

A large number of the content recording media 30 recorded in this way are duplicated, and the duplicated content recording mediums are delivered by direct mail to a plurality of users who are expected to view, or together with periodicals. .

The delivered content recording medium 30 allows the user to reproduce the basic portion of the digital information recorded on the medium, but as a result, when it is desired to view the content as normal content, The user side requests the content information distributor side to reproduce the proper content via a communication line (not shown) or the like.

On the side of the content information delivery apparatus 10 that has received the request, the digital content is encoded again by the encoding unit 11, and the encoded signal that has been encoded is supplied to the code dividing unit 12, and the encoded signal is supplied. The code division unit 12 obtains a coded signal related to a functional portion that forms a pair with the basic portion of the coded signal divided and recorded in the content recording medium 30, and the signal of the obtained functional portion is the personal information unit 14. Is supplied to.

In the personal information section 14, an identification signal relating to an individual who is requested to transmit a signal is generated, a signal relating to, for example, an encryption key is generated based on the generated identification signal, and these are generated. The personal information signal, the encryption key information signal, the division information signal supplied from the division information unit 13, and the coded signal related to the functional portion are supplied to the digital modulation unit 15.

The digital modulator 15 performs digital modulation for transmitting those signals through the content transmission line, and the digitally modulated signal is supplied to the content transmission line 20 through the signal transmission unit 16. .

In this way, the digitally modulated signal is received by the signal receiving section 41 of the content information receiving device 40 installed on the user side, and the received signal is demodulated by the digital demodulating section 42 to obtain the demodulated signal. Is obtained.

Of the obtained demodulated signal, the signal relating to the functional part of the coded signal is supplied to the code assembling section 47.
In the code assembling unit 47, the content recording medium 30
Is reproduced by the signal reproducing unit 45, the reproduced signal is digitally demodulated by the digital demodulating unit 46, and the signal relating to the basic part of the coded signal obtained by demodulation is also supplied to the code assembling unit 47.

In this way, both the basic part and the functional part of the coded signal supplied to the code assembling part 47 are combined there to obtain a regular coded signal. At that time, the two combined signals are combined. Need to be in a synchronous relationship on the time axis, and the synchronization does not show the time relationship in which the content recording medium is reproduced by the signal reproducing unit 45 to the functional portion of the encoded signal supplied via the content transmission path. The synchronization circuit synchronizes the two signals supplied to the code assembling unit 47 on the basis of the signal supplied from the synchronization circuit.
At 7, the regular encoded signal is obtained.

In order to obtain the regular encoded signal, when the encoded signal of the functional portion to be transmitted is encrypted by the encryption key and is supplied, the encryption key is used for the digital demodulation unit. The personal information demodulated and supplied by 42 is supplied to the personal information acquisition unit 43, the encryption key is acquired by decrypting the encryption key based on the personal identification information supplied thereto, and the acquired encryption code is acquired. In the code assembling unit 47 using the key, the decrypted signal of the functional portion is combined with the signal of the basic portion to obtain a regular encoded signal.

The coded signal thus obtained is supplied to the decoding section 48, where the signal coded by MPEG2 or the like is decoded, and the digital content signal obtained by the decoding is obtained. A content signal is converted by an A / D converter (not shown) and supplied to the display unit 50. When the content is displayed on the display unit and an accompanying audio signal is supplied together, the decoded audio is output. The signal is produced by a speaker built in the display.

In this way, when the content is displayed as a result of the decryption of the personal information, the user side is charged a fee for viewing the content based on the personal information transmitted by the content information delivery apparatus 10. As billed, the legitimate content is played with the legitimate viewing charges.

Since the information amount of the content transmitted through the content transmission line 20 in this way may be the information excluding the information amount recorded in the content recording medium 30, the transmission capacity of the content transmission line is Therefore, it is possible to supply a high-quality content without using a transmission line having a sufficiently large capacity.

The method of transmitting the content by combining the basic portion of the encoded signal and the functional portion of the encoded signal transmitted by the content transmission medium on the content recording medium has been outlined above. A method of dividing a signal and the like will be described when the content is a video signal and when the content is an audio signal.

First, a method of dividing an encoded signal when the content is a video signal will be described by taking an example of encoding by a typical compression encoding method. That is, recently, with the progress of compression technology, it has become possible to compress video information with little deterioration in image quality. As a representative example of the compression method, there is an international standard compression method called MPEG. An example applied to the created video stream will be described.

In the MPEG encoding, the image data forming the screen is divided into macroblocks of 16 pixels in the vertical direction and 16 pixels in the horizontal direction, and motion compensation prediction is performed for each of the divided image data of the macroblocks. This is a coding method for coding while.

That is, in the motion-compensated prediction, a motion amount called a "motion vector" is obtained between a reference image and a coded image that are separated by a predetermined number of frames in the future or in the past, and the motion amount is calculated. This is a technique for encoding a coded image from a reference image based on this, and the error signal of the motion compensation prediction or the coded image itself is coded using an orthogonal transform technique.

As the orthogonal transform technique, DCT (Disc
rete cosine transform (discrete cosine transform) is used to transform image information into frequency information, and compression coding is performed so that only visually significant information is obtained from the transformed frequency domain information. Based on technology.

FIG. 2 shows a first motion compensation prediction example of an image coded by MPEG2 in this way. In the figure, the relationship between the image to be encoded and the motion compensation prediction performed on the image is shown.

That is, in the motion compensation prediction, the past, future,
And there are three modes for prediction from both past and future, and their prediction directions are picture types given to the frame of the input image, that is, I (Intra-coded), P (P
redictive-coded) and B (Bidirectionally predict)
ive-coded).

The I picture is a picture that is intra-picture coded without performing motion prediction, and the I picture itself is coded without reference to other pictures. On the other hand, a P picture is a picture that is predictively encoded, and is predicted and encoded in one direction from a past (temporally earlier) I or P picture.

The B picture is a picture that is predictively coded similarly to the P picture, but the P picture predicts based on the past picture, while the past and future (after this in time). It is a picture that is predicted in both directions from I or P pictures and coded.

Of the picture data thus obtained, three types of pictures of I, P and B are arranged in a predetermined order with the I picture as the head and transmitted, and the I picture next to the I picture is transmitted. GOP (Gro (Gro)
Up of Picture), and in encoding performed on a normal storage medium, about 15 pictures are used for G
The OP is constructed.

Although the structure formed by combining the three types of pictures of I, P, and B is used for general MPEG2 encoding, other combinations may be used.

FIG. 3 shows a second motion compensation prediction example of an image coded by MPEG2. In the figure, I pictures or P pictures and B pictures are alternately arranged, but the number of I pictures is very small compared to the number of P pictures.

FIG. 4 shows a third motion compensation prediction example of an image coded by MPEG2. In the figure, a plurality of B pictures are arranged after the I picture, and the B pictures are configured such that image data is transmitted by motion compensation prediction from the I pictures on both sides.

An example of a combination of I, P, and B pictures used in a typical motion compensation prediction method has been shown above. In any of the examples, the number of I pictures is smaller than that of P or B pictures. Since the I picture is an important basic picture that influences the image quality of the moving image to be transmitted, a large amount of code is generally assigned.

That is, even in the case where one I picture exists for every 15 pictures as shown in FIG. 2 described above, for example, one I picture is allocated with about half the code amount of the whole. , The other half of the code amount is allocated to 14 P and B pictures.

As described above, in the encoding using MPEG2, the image of the I picture is first transmitted, and the image of the I picture is used to encode the P picture and the image of the B picture by the motion compensation prediction method. It is transmitted after being converted, and the operation on the decoding side is also complemented.

That is, in decoding a signal encoded by MPEG2, an I picture is first decoded, and then a P picture and a B picture are decoded. Therefore, the image quality of the decoded video is contributed by the image quality of the I picture. The I picture is coded with a large amount of data assigned to it and a large amount of data is allocated to the I picture. Therefore, it can be said that the coded data of the I picture is data for obtaining a high-quality image.

On the other hand, in the other 14 pictures, the information related to the motion of the moving picture is coded and transmitted, and the coded data for that is related to the motion which is functional with respect to the high quality image data. It can be said that the data is encoded data for expressing.

In this way, the moving image data encoded by MPEG2 can be roughly divided into a data portion relating to the quality of the image and a data portion relating to the performance of the moving image. Is transmitted by the content recording medium 30 shown in FIG. 1 and performance-related data is transmitted by the content transmission line 20.

Then, when the user first plays back only the content recording medium, it is possible to decode and display high-quality image data for each 15 pictures, but with high performance. When you want to view as a moving image, you can reproduce the normal moving image by obtaining the encoded data of the information part related to the moving image via the content transmission line and combining the obtained information of the two contents. Becomes

Next, a configuration example of a content information delivery system using the recording medium and the transmission medium will be described. FIG. 5 shows the configuration of a content information delivery system that delivers content information.

The content information delivery system shown in the figure includes a content center 1, a content transmission line 1a, a content transportation line 1b, a signal receiving device 2, and a received signal transmission line 2.
a, a content storage medium 3, a medium signal transmission line 3a, a content decoding device 4, and a content transmission line 4a.

Next, the delivery of the coded video signal by the content information delivery system configured as described above will be described. First, video content including I, P, and B pictures encoded by MPEG2 is stored in a digital storage medium such as a hard disk in a content center.

Then, the content information relating to the I picture of the video content consisting of the I, P and B pictures is recorded in a content recording medium such as a DVD in advance and delivered to a plurality of users by a publisher or the like. .

On the user side, the delivered content recording medium is reproduced, and the I picture data obtained by the reproduction is decoded by the content decoding device 4, and the decoded still image file-like but high-quality file is obtained. The image information is supplied to and displayed on, for example, a display device via the content transmission path 4a.

When a user who views a high-quality reproduced image desires to view the content information as moving image information, he requests the content center 1 to transmit performance information for animation, and the content center 1 transmits the moving image. Video content including P and B pictures for conversion is supplied via the transmission line 1a.

The signals relating to the supplied P and B pictures are received by the signal receiving device 2 and are supplied to the content decoding device 4 via the received signal transmission line 2a, where the I reproduced from the content recording medium. Combined with the signal of the picture, the content is decoded as a regular moving image signal, and the decoded signal is supplied to a display device or the like and displayed as a moving image signal.

Here, in the video content consisting of I, P, and B pictures, the I picture is supplied to the content recording medium, and the P and B pictures are supplied via the transmission path. There is also a method.

The opposite method is to supply the P and B pictures to the content recording medium and the I picture via the transmission path. In this case, when the content recording medium on which P and B pictures are recorded is reproduced, since the signal is a signal of a difference with respect to the I picture, the reproduced signal is a random moving image signal and the content of the content is recognized. You cannot do it.

The content picture can be reproduced only after the I picture signal supplied through the transmission path is supplied to the content decoding apparatus 4. Therefore, the method of supplying the I picture through the transmission path is preferable for the software with high confidentiality of contents.

Since the I picture and the P and B pictures have almost the same code amount in the method for supplying the I picture shown here and the method for supplying the P picture and the B picture, respectively, In either case, the data rate required at the time of transmission is to transmit the content portion not recorded on the content recording medium by using the transmission path having a data rate of about 1/2 for transmitting the entire content. become.

There is also a method in which the storage device of the content center for storing the content portion stores only the information of the content necessary for transmission in response to the request from the user. In this method, the content recording medium is recorded. By deleting the content portion that is not needed at the end time, the information amount of the content stored in the storage device can be reduced, and the storage efficiency of the storage device can be improved.

As described above, in the content information delivery system in which the content is divided into two parts, one is by the recording medium and the other is by using the transmission path, the amount of information to be transmitted from the content center is The content can be transmitted at a transmission rate that is about half the transmission capacity of the content, and it is easy to realize features such as real-time reproduction, shortened delivery time, and high quality.

Further, when recording I picture data on the content recording medium, a part of the content information can be provided to the user side, and when supplying it as P and B picture data, it has no meaning by itself. It is possible to select the necessary providing method according to the purpose, such as being able to provide it as random moving image information, and especially for content that is aware of illegal copying prevention, the latter providing method can be used to solve the problem of illegal copying. It is possible.

When recording and distributing information as a still picture file in which I picture data is recorded on a content recording medium and it is necessary to prevent illegal copying of the still picture file, the I picture The data can be realized by a service form such as taking illegal copy prevention measures or distributing storage media for a fee.

The operation of the content information delivery system in which the encoded video signal is divided into two and one is delivered by the recording medium and the other is delivered by the transmission medium has been described above. Next, examples in which the content is a digital audio signal and the case where the content is a compression-encoded audio signal will be described.

FIG. 6 shows a method of sampling an analog audio signal to obtain a PCM digital audio signal. In the figure, the analog audio signal is sampled with a predetermined time interval ts as a sampling time interval, and the amplitude value of the sampled signal is quantized PCM.
It is obtained as data.

The ordinary digital audio signal thus obtained is normally quantized by the number of bits of 16 and the dynamic range at that time is about 96 dB obtained by multiplying the number of bits by 6.

When the audio signal quantized with 16 bits is divided into an upper 8-bit signal and a lower 8-bit signal, the upper 8-bit signal is a digital audio signal having a dynamic range of about 48 dB. , The lower 8 bits are random signals except when the signals are audio signals with very small amplitude.

Therefore, a method of dividing the digital audio signal into two signals of upper 8 bits and lower 8 bits and distributing them in two by a recording medium and a transmission medium will be described. FIG. 7 shows an example of the configuration of a digital audio content information delivery system for recording the upper 8-bit digital audio signal on a content recording medium.

In the figure, the upper 8 bits of the 16-bit digital audio signal are recorded on a content recording medium and supplied to a large number of users, and the user reproduces only the medium and the dynamic range is about 48 dB. It can be reproduced as a signal.

Further, when reproduction with higher sound quality is desired, lower 8 bits of data are obtained from the content center through a transmission line, and the obtained data is used as an upper 8 bits of audio signal recorded on a recording medium. Dynamic range is about 96dB when combined with H
It can be obtained as an i-Fi digital audio signal.

This is a case where an audio signal to some extent can be obtained only by the recording medium, but there is also the opposite division method. FIG. 8 shows a configuration example of a digital audio content information delivery system when the lower 8 bits are recorded on a content recording medium.

In the figure, the lower 8 bits of the 16-bit digital audio signal are recorded on the content recording medium and supplied to a large number of users, but the user cannot reproduce the audio signal even if the medium is reproduced.

Therefore, by obtaining high-order 8-bit data from the content center via the transmission line and combining the obtained data with the low-order 8-bit audio signal recorded on the recording medium, the dynamic range is about 96d.
A B HiFi digital audio signal can be obtained.

As described above, the audio signal converted into the digital signal is divided into two, one of which is supplied by the content recording medium and the other of which is supplied by the content transmission line, and the reproduced two signals are supplied on the reproducing side. The method of reproducing as a high quality signal by combining is described.

The transmission of such a high-quality audio signal can be applied to a compression-encoded audio signal. Next, regarding an example of applying the compression-encoded audio signal, MPEG2 An example of a compression coded signal by the AAC method will be described.

FIG. 9 shows the MPEG2-AAC (Advanc
An example of a bitstream format according to an LC (Low Complexity) profile of ed audio coding is shown.
In the figure, the bit stream according to the MPEG profile of MPEG2-AAC is composed of two parts, a header part for specifying a transfer format and an audio block for describing audio information.

There are two types of transfer formats, one for editing and one for storing. Here, the editing format in which the synchronization code and the information of the frame length are described in the header will be mainly described.

In the editing format, audio block data is transferred following the transfer format header, and the audio block is composed of a plurality of data units called elements.

That is, the data unit is, for example, when the audio channel structure is 5.1 channel audio,
The channel signals are the front left signal L, the center signal C,
Right signal R, surround signal for left SL, right S
R and a signal for heavy bass LFE.

The method of delivering these signals is as follows. First, the channel information is PCE (Program Config El
ement), then C of the front center signal is SCE (Single
Channel Element) mode, and L of the front left signal,
The right signal R, the left signal SL for the surround signal, and the right signal SR are transmitted in the CPE (Channel Pair Element) mode, and the deep bass signal LFE is transmitted in the SCE mode. A bit filling signal FIL (Fill Element) for transmission and an END (Term Element) indicating the end of the frame are transmitted at the end of the block.

In this way, the transfer format header and the audio block data following it are transmitted. For example, the surround signals SL and SR are recorded on the content recording medium, and other signals are supplied through the content transmission path. In such a case, the surround signal is reproduced only to the user who reproduces only the content recording medium, and the desired user can obtain the audio signal of the remaining channel through the content transmission path. is there.

In particular, in terms of content copyright management,
When it is impossible to reproduce only on the recording medium, the lower bits are recorded on the content recording medium and the upper bits are transmitted by the content transmission medium, as in the case of the above-mentioned example of the uncompressed encoded signal. You can do it like this.

As described above, a method of dividing a signal compression-encoded by MPEG2-AAC into two signals and recording a coded bit stream on the content recording medium so that partial information of the content information can be reproduced, The method of recording the content information as a part of the bitstream that cannot be reproduced at all has been described. Then MPEG2-AA for generating such a bitstream
The configuration of the C encoder is shown, and an application example in that case is described.

FIG. 10 shows the structure of an encoder based on the MPEG2-AAC system. The encoder 70 in the figure includes a psychoacoustic model 71, a filter bank 72, and a TNS (Temp).
oral noise shaping) 73, intensity stereo 7
4, an M / S (Middle Side) stereo 75, an iteration loop 76, and a multiplexing means 77.

In the re-encoding unit 70 thus configured, the supplied audio signal is supplied to the filter bank 72, and in the filter bank 72, the MDCT (Modified Discr) is applied to the signal of the predetermined block length set.
ete cosine transform) operation is performed to obtain the MDCT coefficient.

A part of the MDCT coefficient signal is supplied to the multiplexing means 77 as a bit stream format signal, and the other part of the MDCT coefficient signal is supplied to the TNS 73 and is a signal on its frequency axis. The signal of the MDCT coefficient is regarded as a signal on the time axis, and a noise shaping process, that is, a filtering process is performed so that the noise component is concentrated on a portion where the amplitude of the signal on the time axis is large.

A part of the filtered signal is supplied to the multiplexing means 77 as a bit stream format signal, and the other part of the signal is supplied to the intensity stereo 74.

In the intensity stereo 74, the sense of arrival in the high frequency component of the audio signal is sensed by the difference in the acoustic energy generated as the left or right sound source, so that the stereo acoustic signal is equal to the sum signal of the left and right channels and the left and right channels. Encoding is performed by dividing the difference into the energy (power) difference of the channel signal.

A part of the signal coded in this way is supplied to the multiplexing means 77 as a bit stream format signal, and the other part of the signal is M / S stereo 75.
Is supplied to.

In the M / S stereo 75, the left and right channel signals are generated as their sum signal (main signal: main) and difference signal (sub signal: sub), and their sum,
In addition, the difference signal is encoded, and the signal localized in the center of the left and right channels has a small difference signal level, so that the encoding efficiency can be improved.

A part of the signal encoded by the M / S stereo 75 is supplied to the multiplexing means 77 as a bit stream format signal, and the other part of the signal is supplied to the iteration loop 76. To be done.

In the iteration loop 76, in the frame in which the quantized data is arranged so that the quantization noise level of the encoded audio signal becomes equal to or lower than the allowable noise level obtained by the psychoacoustic model 71. The number of usable bits is calculated.

The operation for obtaining the number of bits includes an inner iteration loop and an outer iteration loop. In the inner iteration loop, the number of bits required for quantization is within the usable number of bits given to the target transmission rate. The number of quantization steps is variably controlled so that

Then, in the outer iteration loop, the level of the quantization noise in each scale factor band based on the quantization step obtained in the inner iteration loop is larger than the allowable noise level obtained in the psychoacoustic model 71. The quantization scale factor is controlled so that it does not occur.

The coded data of the acoustic signal generated based on the quantization step and scale factor thus set is supplied to the multiplexing means 77 as a bit stream format signal.

In the multiplexing means 77, the filter bank 72, TNS 73, intensity stereo 74, M /
The bit stream format signals supplied from the S stereo 75 and the iteration loop 76 are multiplexed in such a manner that the signals in the bit stream format are arranged at positions of a predetermined format, whereby a coded bit stream is generated and supplied. .

Then, the MPEG2-AAC encoder 70
Although a part of the audio signal supplied to the audio psychological model 71 is also supplied to the psychoacoustic model 71, a frequency analysis is performed to obtain a masking level for each frequency so that the masking level is not perceived by the auditory sense as noise. An encoded bitstream encoded at a predetermined transmission rate is generated based on the masking level and output.

Normally, each signal supplied to the multiplexer is generated as one encoded bit stream, but here, the multiplexer 77 generates two encoded bit streams. , One of the bit streams is an encoded bit stream for recording a content recording medium, and the other is a bit stream for transmission via a content transmission path.

One of the two bit streams is a bit stream generated by multiplexing the information obtained by decoding the information related to the content, and the other bit stream is the information related to the content obtained by decoding it. In the content recording medium, one of the bitstreams is recorded on the content recording medium.

The method of generating two bit streams in the case of encoding by the MPEG2-AAC system has been described above, but the same configuration can be applied when the compression encoding system is another system.

That is, of the acoustic information obtained by encoding, two bit streams are generated, a bit stream that can reproduce a part of the acoustic information signal by decoding and a bit stream that cannot reproduce the acoustic signal at all. Both the content recording medium and the content transmission medium are used to supply these bit streams.

As a method of dividing the two bit streams, for example, of audio signals obtained through the filter bank 72, one is a signal obtained by encoding low-range and mid-range acoustic signals, and the other is only high-range signals. There is a method of dividing in frequency so as to be composed of a signal obtained by encoding an acoustic signal.

In this case, the middle and low frequency signals can withstand the listening as music, but the signals in the high tone only, that is, the signals in the high tone only like sound leakage from the headphones are unacceptable for listening. However, there is also a method of splitting such two types of acoustic signals.

The division method relating to the frequency band has been described above, but a method of temporal division can be considered as another method. That is, in the compression encoding method of the audio signal that is usually performed, a time interval called "frame" is defined, and the time interval is "a part of the bit stream that can be decoded by itself".

The time interval is defined as a time interval of 384 samples in layer 1 in MPEG1 audio and a time interval of 1152 samples in layers 2 and 3 as one frame time interval.

However, since the minimum time unit that can be decoded by the content decoder is a frame, every other frame signal is transmitted and supplied as two bit streams on the content recording medium and the content transmission path. In such a case, every other frame signal is reproduced as a discontinuous acoustic signal, which is not preferable.

Therefore, when dividing in time, two samples, that is, a sample point signal in which sample points of acoustic signals for two frames are arranged alternately and a sample point signal arranged in a predetermined random order, are used. A point signal is generated, one of which is recorded as an information signal containing content information and the other is recorded as an information signal not containing content information on a content recording medium or is supplied to a content transmission line.

At this time, in the content decoding apparatus, the sample point signals arranged in random order are converted into signals in a predetermined time order, and are inserted between the sample point signals arranged every other row. The audio signals are reproduced by rearranging the sound signals in a regular sample order.

As described above, the compressed and encoded video contents,
The uncompressed coded audio signal content converted into a digital audio signal and the compression-coded audio signal content have been described, but in any case, the first code for obtaining some information related to the content The encoded signal portion and the second encoded signal portion from which information on the content cannot be obtained by decoding, one of the obtained signals is used as the content recording medium, and the other is used with the content transmission line. The content information is supplied to the user so that any one of the reproduction states of the recording medium can be obtained depending on the state of the content to be protected.

Then, the recording medium is delivered to the user by transportation means or the like, but the user who cannot deliver the recording medium can obtain the information recorded in the recording medium through the communication line if desired. In that case, for example, a hard disk is provided in the content recording medium unit 3 in FIG. 5 described above, information of a portion to be recorded in the content recording medium is obtained from the content center via the transmission line, and the obtained information is stored in the hard disk. This is a case of storing and using.

At that time, the user bears only the cost of transmission, and the cost of copyright of the content is generated only when receiving the content information to be transmitted through the content transmission line.

When the user desires to obtain all the information related to the content, the remaining coded signals in the content center managed by the copyright holder are supplied through the content transmission line. Billing information relating to the copyright is also generated and transmitted to the user in response to the supply of the signal through the content transmission path, and the user pays the fee according to the billing information.

The data amount of the content information transmitted through the transmission path is sufficient because the content can be transmitted in real time at a rate of, for example, 1/2 of the bit rate required for transmitting all the content data. Even when a communication path that cannot secure a transmission rate is used, the same content data as when all content data was transmitted can be decoded.

When performing such content data supply management, for example, all content data protected by a key is recorded on a recording medium and supplied to the user, and the user supplies the encryption key via a transmission line or the like. There is a method to obtain the decryption permission of the re-contents by getting it, but if the encryption key is illegally obtained by another user,
Since the encryption key is no longer available to a plurality of other users, the content protection management is no longer possible.

On the other hand, the entire content is decrypted based on the content information such that the difference information of the content having a much larger amount of information than the encryption key shown here is transmitted through the transmission path. In the case of such content protection, it is difficult for an encryption key to be illegally obtained, and it is possible to strictly manage content information.

The information amount of the content information transmitted through the content transmission path is generally larger than the general encryption key information amount, and is smaller than 1/2 of the total content information amount. Will be used.

[0129]

According to the first aspect of the present invention, a predetermined portion of the content on the content distributor side is encoded in advance to obtain a first encoded signal portion, which is recorded on a medium and transported to the user side. However, in order to supply the second coded signal portion that does not include the first coded signal portion to the user side via the transmission line in response to the request from the user side, the user side does not use the recording medium. By combining the recorded information signal for recording and the information signal for transmission transmitted by the communication network, high-quality content information is obtained, and the copyright of the high-quality content information is protected. There is an effect that a delivery method can be provided.

Further, according to the invention described in claim 2, in addition to the effect described in claim 1, particularly, each of the first coded signal portion and the second coded signal portion both compresses the content signal. It is either a coded signal that has been coded or a coded signal that has been converted into a digital signal, so it is a signal that has been compression coded, and has not been compression coded. There is an effect that high-quality content information can be obtained for both of the encoded signals, and a content information delivery method in which copyright protection is provided for the high-quality content information can be provided.

According to the invention of claim 3, in addition to the effect of claim 1, particularly, the first coded signal portion is
Since it is either one of the signal composed of a plurality of bits in the upper direction of the digital content signal or the signal composed of a plurality of bits in the lower direction, the first encoded signal portion and By reproducing both of the second coded signal portions, it is possible to obtain high-quality content information and to provide a content-information delivery method in which copyright protection is provided for the high-quality content information. .

According to the invention described in claim 4, in addition to the effect described in claim 1, in particular, the first coded signal portion is
The first coded signal portion and the second code, which are either the intra-frame coded signal of the compression-coded video signal or the inter-frame predictive coded signal. By reproducing both of the high-quality signal portions, high-quality content information can be obtained, and there is an effect that it is possible to provide a content information delivery method in which copyright protection is provided for the high-quality content information.

According to the invention of claim 5, in addition to the effect of claim 1, in particular, the first coded signal portion is the content of the content of the coded audio signal when it is decoded. Reproducing both the first coded signal part and the second coded signal part because the signal is one of a signal for which some information is obtained and a signal for which content information is not obtained. Thus, there is an effect that a high-quality content information can be obtained and a delivery method of the content information whose copyright is protected with respect to the high-quality content information can be provided.

According to the invention described in claim 6, the predetermined portion of the content on the content distributor side is encoded in advance to obtain the first encoded signal portion, which is recorded on the medium and transported to the user side. However, in order to reproduce the signal supplied to the user side through the second coded signal portion not including the first coded signal portion in response to the request from the user side, On the side, high-quality content information can be obtained by combining the recording information signal recorded on the recording medium and the transmission information signal transmitted by the communication network, and the copyright protection for the high-quality content information can be obtained. There is an effect that it is possible to provide a method of reproducing the made content information.

Further, according to the invention of claim 7, a predetermined portion of the content on the content distributor side is encoded in advance to obtain a first encoded signal portion, which is recorded on a medium and transported to the user side. However, in order to supply the second coded signal portion that does not include the first coded signal portion to the user side via the transmission line in response to the request from the user side, the user side does not use the recording medium. By combining the recorded information signal for recording and the information signal for transmission transmitted by the communication network, high-quality content information can be obtained, and copyright information protection for the high-quality content information is delivered. There is an effect that the configuration of the device can be provided.

Further, according to the invention of claim 8, a predetermined portion of the content on the content distributor side is encoded in advance to obtain a first encoded signal portion, which is recorded on a medium and transported to the user side. However, in order to reproduce the signal supplied to the user side through the second coded signal portion not including the first coded signal portion in response to the request from the user side, On the side, high-quality content information is obtained by combining the recording information signal recorded on the recording medium and the transmission information signal transmitted by the communication network, and the copyright protection for the high-quality content information is protected. There is an effect that it is possible to provide the configuration of the content information reproducing apparatus.

According to the invention described in claim 9, in addition to the effect described in claim 8, in particular, the first coded signal portion supplied in advance from the content distributor side to the user side via the transmission line is provided. Since the information is recorded in the temporary storage medium on the user side and the recorded temporary storage medium is reproduced, the user side records the recording information signal recorded on the temporary storage medium and the transmission information transmitted by the communication network. There is an effect that it is possible to provide a configuration of a content information reproducing apparatus in which high-quality content information is obtained by combining with a signal, and copyright protection for the high-quality content information is performed.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration of a content information delivery system according to a content information delivery apparatus and a content information reception apparatus of the present invention.

FIG. 2 is a diagram showing a first motion compensation prediction example of an image coded by MPEG2 according to an embodiment of the present invention.

FIG. 3 is a diagram showing a second motion compensation prediction example of an image encoded by MPEG2 according to an embodiment of the present invention.

FIG. 4 is a diagram showing a third motion compensation prediction example of an image encoded by MPEG2 according to an embodiment of the present invention.

FIG. 5 is a diagram showing a configuration of a content information delivery system according to an embodiment of the present invention.

FIG. 6 is a diagram showing a method of sampling an analog audio signal to obtain a digital audio signal according to an embodiment of the present invention.

FIG. 7 is a diagram showing a configuration example of a content information delivery system when recording the upper 8 bits of a digital audio signal according to an embodiment of the present invention in a medium.

FIG. 8 is a diagram showing a configuration example of a content information delivery system when recording the lower 8 bits of a digital audio signal according to an embodiment of the present invention in a medium.

FIG. 9 is a LC of MPEG2-AAC according to an embodiment of the present invention.
It is a figure which shows the transmission format example of the bit stream by a profile.

FIG. 10 is a diagram showing a configuration of an encoder according to the MPEG2-AAC system according to the embodiment of the present invention.

[Explanation of symbols]

1 Content Center 1a Content transmission line 1b Content transportation route 2 signal receiver 2a Received signal transmission path 3 Content storage medium 3a Medium signal transmission line 4 Content Decoding Device 4a Content transmission line 10 Content information delivery device 11 Encoding section 12 Code Division 13 division information section 14 Personal Information Department 15 Digital modulator 16 Signal transmission section 17 Digital modulator 18 signal recorder 20 content transmission path 30 content recording medium 40 Content Information Receiving Device 41 Signal receiver 42 Digital demodulator 43 Personal Information Acquisition Department 44 Encryption key acquisition unit 45 Signal reproduction section 46 Digital demodulator 47 Code Assembly Department 48 Decoding section 50 display 70 encoder 71 Auditory psychological model 72 Filter Bank 73 TNS 74 Intensity Stereo 75 M / S stereo 76 iteration loop 77 Multiplexing means

─────────────────────────────────────────────────── ─── Continued Front Page (51) Int.Cl. ⁷ Identification Code FI Theme Coat (Reference) H04N 5/91 H04N 5/91 P 5/92 5/92 H 7/32 7/137 Z F Term (Reference) ) 5C052 AA02 AB04 CC11 DD10 5C053 FA13 FA23 FA30 GB05 GB08 GB21 JA21 LA06 LA14 5C059 KK43 MA00 MA05 MA23 PP05 PP06 PP07 RA09 SS08 SS11 UA02 UA05 5C064 BA07 BB02 G08KL082501

Claims (9)

[Claims] 1. A content information delivery method for delivering content information to a user as encoded content information by a content deliverer, wherein a predetermined portion of the content information at the content deliverer is encoded in advance. Recording the first encoded signal portion obtained as described above on a medium, and transporting the recorded medium to the user, and not including a predetermined portion of the content information in response to a request from the user side. A second step of transmitting a second encoded signal portion obtained by encoding the content portion to the user via a transmission medium having a communication path established between the content distributor side and the user side; A method for delivering content information, comprising: 2. The first coded signal portion and the second coded signal portion.
2. The method of delivering content information according to claim 1, wherein both of the coded signal parts of the above are coded signal parts subjected to compression coding or coded signal parts converted into digital signals. . 3. The first coded signal portion is converted into a digital signal with a bit number of 4 or more at each sampling time,
And upper and lower signal portions, wherein the upper signal portion is a signal portion represented by a plurality of bits in the upper group of the digital content signal represented by a plurality of bits, and the lower signal The part is a signal part represented by a plurality of bits in a lower group of the digital content signal.
How to deliver the described content information. 4. The first coded signal part is the intra-frame coded of a compression-coded video signal composed of an intra-frame coded signal part and an inter-frame predictive coded signal part. 2. The content information delivery method according to claim 1, wherein the signal information is one of a signal portion that has been subjected to interframe prediction coding and a signal portion that has been subjected to interframe predictive coding. 5. The first encoded signal portion is a signal portion relating to a voice signal which is compression-encoded by combining signal portions based on a plurality of compression methods, and when the signal portion is decoded. 2. The method for delivering content information according to claim 1, wherein the signal portion is one of a signal portion in which information of a part of the content is obtained or a signal portion in which information of the content is hardly obtained. . 6. A first coded signal portion obtained by previously encoding a predetermined portion of content information at a content distributor is recorded and supplied on a recording medium and does not include the predetermined portion of the content information. A second encoded signal portion obtained by encoding the content portion is supplied via a transmission medium, and the content information is obtained from the supplied signals of the first encoded signal portion and the second encoded signal portion. A method of receiving content information, comprising: reproducing the recording medium to obtain the first encoded signal portion, and receiving a signal supplied by the transmission medium to obtain the second encoded signal portion. And a second step of obtaining the encoded signal related to the digital content information by combining the first encoded signal portion and the second encoded signal portion. , Method of receiving content information, characterized in that it comprises a third step of obtaining the second of said content information by decoding the obtained encoded signal in step, the least. 7. A content information delivery device for delivering content information to a user as encoded content information by a content deliverer, wherein a predetermined portion of the content information of the content deliverer is encoded in advance. Recording signal generating means for supplying the obtained first encoded signal portion to the medium recorder as a signal for recording on the medium, and encoding a content portion not including a predetermined portion of the content information in response to a request from the user side. Signal transmission means for transmitting the second encoded signal portion obtained by converting the second encoded signal portion to the user side via a transmission medium having a communication path established between the content distributor side and the user side. A content information delivery device comprising at least the configuration. 8. A first coded signal portion obtained by previously encoding a predetermined portion of content information at a content distributor is recorded on a recording medium and supplied, and does not include the predetermined portion of the content information. A second encoded signal portion obtained by encoding the content portion is supplied via a transmission medium, and the content information is obtained from the supplied signals of the first encoded signal portion and the second encoded signal portion. And a signal reproducing unit for reproducing a signal recorded on the recording medium to obtain the first encoded signal portion, and receiving a signal supplied via the transmission medium. A signal receiving means for obtaining the second coded signal portion, and a signal obtained by coding the content information by combining the first coded signal portion and the second coded signal portion. A code assembly means may be, the contents information receiving apparatus, characterized in that it constituted by at least comprising: a decoding means for obtaining the content information by decoding the encoded signal obtained by the code assembly means. 9. The reproduction of the recording medium in the signal reproduction means temporarily replaces the reproduction of the recording medium with the first encoded signal portion previously supplied via the transmission medium from the content distributor. 9. The content information receiving apparatus according to claim 8, wherein the content information receiving apparatus is configured to record on a storage medium and reproduce the recorded temporary storage medium to obtain the first encoded signal portion.