JP6039707B2 - Video signal processing apparatus and method - Google Patents

Description

  The present invention relates to a digital video signal transmission method and a video processing device such as an STB (Set Top Box) for receiving a digital broadcast signal, a television display device or the like.

  With the spread of HD (High Definition) broadcasting through terrestrial digital broadcasting and the release of Blu-ray (registered trademark) recorders that can record HD broadcasting, there is a need for a digital video interface that can transmit high-quality HD video to TV without image quality degradation. Is growing. As an interface for non-compressed video signal transmission, there are DVI (Digital Visual Interface) formulated by DDWG, HDMI (High Definition Multimedia Interface, registered trademark) licensed by HDMI, LLC. Also, there are IEEE 1394, LAN, and the like as an interface for transmitting a video signal compressed by MPEG or the like. For example, Non-Patent Document 1 discloses a conventional technique for applying an uncompressed video signal transmission interface to a television device. This discloses that video format information is packetized and multiplexed and transmitted in an uncompressed video signal that is not packetized. In HDMI, audio data is also packetized and transmitted. Non-patent document 2 describes, for example, a conventional technique for applying a compressed video signal transmission interface to a television device. Examples of copyright protection techniques used for these include HDCP (High-bandwidth Digital Content Protection System) for uncompressed video and DTCP (Digital Transmission Content Protection) for compressed video.

  Further, for example, Patent Document 1 discloses an SDDI (Serial Digital Data Interface) method in which an uncompressed video signal and a compressed video signal are respectively packetized and serially transmitted.

JP-A-8-307455

Standard "CEA-861-B" US CEA 2002 Standard "CEA-775-B" US CEA 2004

  In the future, the types of signal sources are expected to increase, and TVs are increasingly required to have input interfaces for uncompressed video signals and compressed video signals. However, when two types of interfaces with different connectors are provided in a television device (such as a television receiver), it is necessary to secure a connector space and prepare two types of cables. Patent Document 1 discloses a method for transmitting an uncompressed video signal and a compressed video signal at the same time, which is a transmission method suitable for a broadcasting station. That is, in the transmission method described in Patent Document 1, since the uncompressed video signal is packetized, it is difficult to apply it to a television device for general households.

  Also, the types of copyright protection technology used will increase depending on the type of interface handled. Even in such a case, it is necessary to appropriately cope with copyright protection technology.

  The present invention has been made in view of the above problems, and an object thereof is to provide a technique related to an interface capable of transmitting both an uncompressed video signal and a compressed video signal. Another object of the present invention is to provide a technique capable of suitably protecting copyright.

  In order to achieve the above object, in the present invention, an input compressed video signal is decoded to generate an uncompressed video signal, and the compressed video signal is multiplexed and transmitted in a blanking period portion of the uncompressed video signal. It is characterized by doing. Further, the present invention is characterized in that a packetized compressed video signal is multiplexed and transmitted on a non-packetized uncompressed video signal including a synchronization signal. According to such a configuration, for example, both of an uncompressed video signal whose transmission method is defined by a standard such as DVI and HDMI and a compressed video signal whose transmission method is defined by a standard such as IEEE 1394 are used as one type. It is possible to transmit through the interface. Therefore, it is not necessary to secure two connector spaces and to prepare two types of cables, and the cost can be reduced.

  In addition, the present invention is configured to perform a plurality of types of encryption processing on a video signal transmitted or received through one interface, and can select any one of the plurality of encryption processing units. Is the second feature. This selection may be performed in response to a change instruction from the encrypted user.

  According to the present invention, an interface common to an uncompressed video signal and a compressed video signal can be provided. In addition, suitable copyright protection can be achieved.

1 is a block diagram showing a first embodiment of a video processing apparatus according to the present invention. The block diagram which shows the example of 1 structure of the transmission part of a video processing apparatus, and a receiving part The figure which shows an example of the packet structure of compressed video The block diagram which shows 2nd Example of the video processing apparatus which concerns on this invention Block diagram showing a third embodiment of the video processing apparatus according to the present invention. The block diagram which shows the flow of the video signal of the video processing apparatus in 3rd Example. The figure which shows the example of 1 structure of the output circuit and input circuit in 3rd Example The figure which shows the basic structural example of the output circuit and input circuit of a video processing apparatus The block diagram which shows 4th Example of the video processing apparatus based on this invention The figure which shows the example of 1 structure of the output circuit in 4th Example, and an input circuit

  The best implementation liquid of the present invention will be described below with reference to the drawings. In the present invention, an uncompressed video signal and a compressed video signal are simultaneously transmitted through a common (identical) interface. Such transmission is realized while maintaining the interconnectivity with uncompressed digital interfaces such as DVI and HDMI which have started to spread. In the embodiment described below, the video processing device includes, for example, an STB with a built-in digital tuner, a television display device (hereinafter referred to as “TV”), and the like. Of course, the following embodiments can be applied to devices other than these devices.

  FIG. 1 is a block diagram of a first embodiment according to the present invention. An STB (Set Top Box) 11 which is an example of a video processing apparatus, a TV 12 which is another example of the video processing apparatus, and video on the go Is included. Hereinafter, examples of these operations will be described.

  The STB 11 receives an RF signal 101 supplied from a digital broadcast, a cable, or the like, and demodulates a transport stream (hereinafter abbreviated as TS) of a compressed video by the digital tuner 111. From the demodulated TS, a TS / PS converter 112 extracts a program stream (hereinafter abbreviated as PS), and a decoder 113 obtains an uncompressed video signal. The uncompressed video signal and the OSD screen generated by the OSD unit 115 are combined by the video combining unit 114. This uncompressed video signal is transmitted from the transmission unit 117 to the reception unit 127 of the TV 11 via the video signal interface 103 without being packetized. The uncompressed video signal received by the reception unit 127 is sent to the display unit 129 via the video synthesis unit 124. The display unit 129 displays a real-time video screen based on the uncompressed video signal and provides it to the user. The control units 116 and 126 not only control the multiplexing and communication status of the transmission unit 117 and the reception unit 127, respectively, but also transmit the display capability (characteristics and specifications related to video display) of the TV 12 to the STB 11, and transmit from the STB 11. An operation for matching the video signal with the display characteristics of the TV 12 is performed. In addition, bidirectional communication control can be performed so that the STB 11 and the TV 12 can cooperate with each other by exchanging remote control codes.

  On the other hand, the TS output of the digital tuner 111 and the OSD output of the OSD unit 115 are also sent to the transmission unit 117. The transmission unit 117 multiplexes TS and OSD packet data into an uncompressed video signal to generate a multiplexed video signal, and transmits the multiplexed video signal to the reception unit 127 via the interface 103. The receiving unit 127 separates the uncompressed video signal and the TS and OSD from the received multiplexed video signal. The TS and OSD separated or extracted by the reception unit 127 are accumulated in the accumulation unit 128. The storage unit 128 is configured by a hard disk, for example. You may comprise with semiconductor memories, such as flash memory. Thereby, video recording based on TS is performed. The recorded TS is read from the storage unit 128 according to a user instruction, the PS is extracted by the TS / PS conversion unit 122, and an uncompressed video signal is obtained by the decoding unit 123. At the same time, OSD data is also read from the storage unit 128 as necessary, and the OSD unit 125 forms an uncompressed OSD video signal. This OSD video signal is synthesized with the uncompressed video signal output from the decoding unit 123 in the video synthesis unit 124. The uncompressed video signal in which the recorded video and the OSD are combined is displayed by the display unit 129 and can be viewed (time-shifted viewing) in a time zone desired by the user.

  If the TV 12 is equipped with the digital tuner 121, it can receive digital broadcasts and the like as with the STB 11, record the TS in the storage unit 128, and watch the time shift. Further, the uncompressed video signal obtained through the TS / PS conversion unit 122 and the decoding unit 123 and the uncompressed video signal sent from the STB 11 are synthesized by the video synthesis unit 124 and simultaneously displayed on the display unit 129 on two screens. You can also The digital tuners 111 and 121 may receive different channels and synthesize two screens. Further, the channel image received by the terrestrial digital tuner and the channel image received by the cable television tuner may be combined into two screens. If the STB 11 includes a digital tuner 111 different from the digital tuner built in the TV 12 with a digital tuner (that is, a digital tuner that can receive a channel that cannot be received by the digital tuner of the TV 12), real-time viewing of the channel that cannot be received by the TV 12 is possible. And time-shift viewing can be realized. In addition, even after the STB 11 is removed from the TV 12, there is an effect that the video received by the STB and remaining in the storage unit 128 can be viewed.

  If the digital tuner 111 can receive a plurality of channels simultaneously, it is obvious that the compressed video signal and the uncompressed video signal multiplexed by the transmission unit 117 may be different programs. Further, the compressed video data multiplexed by the transmission unit 117 may not be a TS but a PS after TS / PS conversion. Compared with TS, PS has the advantage of reducing the amount of data transmission.

  The compressed video signal recorded in the storage unit 128 is subjected to further high compression and code conversion such as a transmission format by the code conversion unit 130, and then the interface unit 131 such as USB or IEEE1394, the interface 104, and the interface unit 132. Through the storage unit 138. After the transfer of the video signal, the mobile viewer 14 is disconnected from the interface 104 and can be carried anywhere. Then, the mobile viewer 14 decodes the video stored in the storage unit 138 by the decoding unit 133 and displays it on the display unit 139 in accordance with a user instruction. Accordingly, the user can view a desired video at an arbitrary place using the mobile viewer 14.

  FIG. 2 is a block diagram illustrating a configuration example of the transmission unit 117 and the reception unit 127. An example of the operation will be described below. The audio data 202 corresponding to the uncompressed video from the video synthesis unit 114 (FIG. 1), the TS output 203 from the digital tuner 111 (FIG. 1), and the OSD data 204 of the OSD unit 115 (FIG. 1) are respectively transmitted to the transmission unit. 117 is input to the packet generators 211, 212, and 213. The packet generators 211 to 213 form a packet suitable for multiplexing on the uncompressed video signal based on the input signals. The buffer unit 214 receives the packets from the packet generation units 211 to 213, rearranges them according to the priority order of packet transmission, and sequentially transmits them in accordance with the blanking period of the uncompressed video signal. The ECC code unit 215 inserts an error correction code into the packets rearranged by the buffer unit 214. Then, interleaving is performed in units of bits in the interleaving unit 216 to increase the resistance to burst errors, and is sent to the multiplex coding unit 217. The multiplex coding unit 217 multiplexes the interleaved packet with the uncompressed video signal output 201 from the video synthesis unit 114 (FIG. 1), and a copy control flag for the uncompressed video signal. A copy flag assigning unit 402 for assigning a video signal, an encryption processing unit 403 for encrypting a video signal, and a transmission encoding unit 404 for performing transmission encoding. The output of the multiplex coding unit 217 is transmitted to the input circuit 228 of the receiving unit 127 as a multiplexed video signal 207 via the output circuit 218.

  The multiplexed video signal received by the input circuit 228 is sent to the multiplexing / decoding unit 227. The multiplex decoding unit 227 includes a transmission decoding unit 411 that decodes transmission encoding, a decryption unit 412 that decrypts a video signal, a copy flag extraction unit 413 that extracts a copy flag, and an uncompressed video signal 291. And a separation unit 414 that separates other packet data. The packet data is interleaved by the de-interleave circuit 226, restored to the original signal, error-corrected by the ECC decoder 225, and transmitted to the buffer unit 224. The buffer unit 224 temporarily holds the packet data and outputs the packet data to the packet decoding units 221 to 223, respectively. The packet decoding units 221 to 223 decode the packet data from the buffer unit 224 to obtain audio data 292 of uncompressed video signals, TS 293, and OSD data 294. These are data sent from the receiving unit 127 to the storage unit 128 in FIG.

  The capability transmission unit 229 transmits information regarding the display capability (display specifications and / or display characteristics) of the TV to the capability identification unit 219 via the communication line 208. The capability identifying unit 219 identifies the display capability of the TV 12 based on the information regarding the display capability and outputs an identification result 205. The identification result 205 is transmitted to the control unit 116 (FIG. 1). Then, the control unit 116 controls the elements related to video processing or video output in the STB 11 so as to send a video format suitable for the connected TV 12 and confirms the display capability on the TV 12 side. The multiplexed video signal is transmitted. With such a configuration, only the uncompressed video signal is transmitted without transmitting the multiplexed video signal to a TV that does not have a configuration capable of inputting a multiplexed video signal (that is, a TV having a conventional interface). For this reason, the interoperability with a TV having a conventional interface is ensured. As a configuration for transmitting the capability on the TV 12 side, for example, it is preferable to use an EDID system defined by VESA. In this embodiment, the information regarding the display capability of the TV includes, for example, horizontal and vertical resolutions of the display unit 129, a color reproduction range, a gamma characteristic, and the like. Further, in order to effectively use the present embodiment, as information about the display capability of the TV, in addition to the above, for example, a video format indicating the display timing of a multiplexed video signal, a bit rate of a compressed video, a decodable code It is preferable to add additional capabilities such as a list of conversion methods, a storage capacity of the storage unit 128, a free capacity, and a maximum recording speed.

  In addition to the above, the capability transmission unit 229 and the capability identification unit 219 are also used for device authentication and confirmation of cryptographic processing capability. For example, in DVI or HDMI, there is HDCP licensed by Digital Content Protection, LLC as this encryption processing. In the future, with the diversification of content, it may become necessary to manage a plurality of encryption processes for each content or country. In such a case, in this embodiment, a plurality of types of device authentication and encryption processing elements are provided on the video signal receiving side, and which processing is appropriate with reference to the device authentication start protocol from the transmitting side. An automatic discrimination / selection circuit for discriminating and selecting the above may be provided. On the other hand, the transmission side may be provided with an automatic discrimination / selection circuit that discriminates the type of content, the country in which it is used, etc., and selects and switches the encryption processing suitable for the content. For example, a region code recorded on a DVD disk may be read and encryption processing may be selected using the region code. In television broadcasting, the broadcasting station may be identified and encryption processing may be selected.

  Depending on the regulations of the country and business operators, it may be necessary to fix encryption processing. In such a case, if a dedicated video processing apparatus is newly prepared, the development cost can be increased. Therefore, the video processing apparatus may be provided with a plurality of cryptographic processing units capable of executing a plurality of types of cryptographic processing, and may be provided with a determination / selection circuit that determines the type of encryption and selects a cryptographic processing unit corresponding to the determination result. . At this time, the discriminating / selecting circuit may automatically discriminate the type of encryption and perform the selection operation. In addition, a setting circuit for enabling the user to set the type of encryption processing may be provided. In addition, with this setting circuit, one of a plurality of encryption processes may be preset and fixed at the time of shipment. In this case, the procedure related to the setting change of the encryption process (for example, input of a command or password to the STB 11 or the TV 12) is kept secret from the user so that the user cannot change the setting of the encryption process by the setting circuit. It is good to keep it. When changing the encryption processing settings after shipment, the procedure for changing the settings can be downloaded from, for example, broadcasting and / or the Internet under specific conditions (for example, charging a fee from the user). May be. In this way, the procedure is disclosed to the user under a specific condition for the above-described setting change that is concealed, and the change of the encryption process by the user becomes effective. When implementing this example, such a service may be provided. Furthermore, the procedure relating to the setting change may be stored in a storage medium such as a DVD and distributed to the user as a setting change DVD.

  Furthermore, when various cryptographic processes are used, the image quality can be changed by limiting the resolution and the bit rate of the compressed video signal depending on the grade of the cryptographic process.

  The communication circuits 220 and 230 perform bidirectional communication via the communication path 209, and transmit and receive control information between the control units 116 and 126 in FIG. For example, as the bidirectional communication in this embodiment, for example, a bidirectional communication configuration such as CEC defined by HDMI can be applied. When an error that cannot be corrected occurs in the ECC decoding unit 225, the TV 12 transmits a retransmission request to the STB through the communication path 209, and the STB 11 retransmits the compressed video signal in which the error has occurred in response to the retransmission request. It may be. As a result, error-free recording becomes possible. The compressed video signal packet included in the compressed / uncompressed video signal multiplexed signal 207 is given an identification number and a symbol such as a time stamp, so that the TV 12 sends the error packet number and symbol to the STB 11 together with a retransmission request. You may make it transmit. Thus, when a retransmission request is generated, the STB 11 can retransmit only the error packet with reference to the error packet number or symbol. For this reason, since the STB 11 does not need to retransmit a packet having no error, the transfer efficiency is improved.

  The packet transmission process in the buffer unit 214 described above, that is, the packet rearrangement process according to the priority order will be described below. There is a limit to the transmission capacity of packets that are multiplexed and transmitted on an uncompressed video signal. The packet to be sent with the highest priority is the sound of an uncompressed video signal that needs to be reproduced in real time in synchronization with the video. Therefore, the priority of the audio packet of the uncompressed video signal is set highest, and the arrangement is determined with the highest priority. In the remaining area, a compressed video packet and an OSD packet are arranged. The priority order of the compressed video packet and the OSD packet is arbitrarily determined. When the OSD is related to (or highly relevant to) the uncompressed video signal, the priority order of the OSD packet is set higher than that of the compressed video packet. May be. When the necessity of using compressed video in the TV 12 is high, the priority of the compressed video packet may be set higher than that of the OSD packet.

  When sending compressed video to the storage unit 128, it is necessary to arrange packets so as not to exceed the maximum recording speed of the storage unit 128. Alternatively, flow control may be performed by the communication path 209 to control the packet transmission amount. When the compressed video is reproduced on the TV 12 in almost real time, it is necessary to control the packet transmission amount in accordance with the encoding speed of the compressed video.

  Depending on the format of the uncompressed video signal, the packet transmission capability for multiplexing the compressed video signal may be insufficient. In this case, a format in which the pixel clock of the uncompressed video signal is multiplied by n (n is 2 or more) or the blanking period of the uncompressed video signal is extended may be used. In this way, the packet transmission capability of the compressed video signal can be improved.

  FIG. 3 is a diagram illustrating an example of a packet structure of compressed video. As shown in FIG. 3, a TS packet is composed of a total of 188 bytes including a 4-byte header and a 184-byte adaptation (or payload). On the other hand, in order to multiplex TS in a gap (for example, a blanking period) between uncompressed video signals, a smaller packet size is better. FIG. 3 shows a case where a packet is composed of a 3-byte header and a 28-byte payload. The TS packet 188 bytes may be divided into 7 compressed video packet payloads for transmission.

  An example of the configuration of the header will be described below. The first byte represents a packet type such as compressed video or audio. The total 16 bits of the second byte and the third byte may be allocated to the order of the TS packet divided into seven (3 bits), the TS packet number (11 bits), and the copy control flag (2 bits). The TS itself also includes a time stamp, and by using this, the 11 bits of the TS packet number in the header may be omitted, but it is easier to use it if it is described in the header part. Using this TS packet number as an identification number for identifying a packet, the above-described retransmission request packet is designated when a transmission error occurs.

  For example, when transmitting HD video at 20 Mbps, 108,000 TS packets of 188 bytes are transmitted per second. When a reproduction request is made to the transmission side when a transmission error occurs, if the speed of the communication path 209 is slow (that is, the transfer rate is low) and 100 mS is required for transmission of error information, a TS that discriminates at least 10,000 TS packets. A packet number is required. That is, 14 bits are required for the TS packet number, and 11 bits in the header portion are insufficient. On the other hand, as shown in the figure, the payload of the seventh compressed video packet has 8 bytes of free space. Therefore, 1 byte of this empty area may be used to describe the missing TS packet number. Of course, 2 to 3 bytes may be used as necessary. Also, the copy flag may be described in this empty area instead of the header. When there is a margin in the area, the number of copies, the storage time limit for allowing time shift viewing after transmission, and / or CGMS-D can be described. If more information description is required, 8 compressed video packets instead of 7 may be applied to one TS packet.

  FIG. 4 is a block diagram showing another embodiment of the present invention. In the present embodiment, in the system configuration shown in FIG. 1, the transmission unit 117 and the reception unit 127 are changed to the transmission unit 230 and the reception unit 250 in FIG. 4, respectively. In this embodiment, the transmission unit 230 and the reception unit 250 are connected to each other through an interface including three data lines 271, 272, and 273 that transmit video signals and a clock line 274 that transmits a clock signal. To do. The three data lines are used for transmitting uncompressed video signals of red, green and blue, for example. The clock line transmits a reference clock for data reception. The data line is assumed to send 10 data during the clock cycle through the clock line. Multiplex encoding units 231 to 233 and 235, output circuits 241 to 244, input circuits 251 to 254, and multiplex decoding units 261 to 264 are respectively the multiplex encoding unit 217, output circuit 218, input circuit 228, and multiplex decoding shown in FIG. This corresponds to the unit 227, and detailed description thereof is omitted. The description of other blocks shown in FIG. 2 is omitted here.

  The case where the switch 245 selects the clock supply unit 234 corresponds to the embodiment of FIG. In this embodiment, when it is necessary to increase the speed of video data transmission, the switch 245 is switched to the multiplex coding unit 235, and the clock line is also used as the data line to increase the video data transmission amount by 4/3. . In this case, the reference clock for reproducing the input data on the TV 12 side may be used by extracting the reference clock from the signal of each data line, not the clock signal transmitted through the clock line. For this purpose, all or at least one of the received signals of each of the input circuits 251 to 254 may be led to the PLL 256 to extract a clock component from the input data. For extraction of clock components, a band pass filter or the like may be combined with a PLL or the like. Of course, the PLL may be replaced with a DLL.

  Now, there are various formats for video data, and there are many reference clocks. When the clock is extracted from the data line and used as the reference clock as described above, it is necessary to accurately detect the reference clock period, and therefore, a long time is required. In this embodiment, in the initial state, the switch 245 selects the clock supply unit 235 and transmits the reference clock from the clock supply unit 235 to the reception unit 250 through the clock line 274. Thus, the reference clock cycle can be easily transmitted to the receiving unit 250. Therefore, according to the present embodiment, there is an effect that the time for the initial setting related to the period of the reference clock can be shortened.

  If the configuration for transmitting the information regarding the display capability of the TV 12 described in the form of FIG. 2 to the STB 11 is used, it is determined whether the receiving unit 250 has a mode for using the clock line as a data line. Can tell. The time required for initial clock cycle extraction can be communicated as well. In addition, if the bidirectional communication path 209 shown in FIG. 2 is used, it is possible to notify the transmission unit 230 from the reception unit 250 that the initial setting has been completed.

  FIG. 5 is a block diagram showing another embodiment of the present invention. In the present embodiment, in the system configuration shown in FIG. 1, the transmission unit 117 and the reception unit 127 are changed to the transmission unit 240 and the reception unit 260 in FIG. 4, respectively. The same components as those in the embodiment shown in FIG. 4 are given the same numbers. In the present embodiment, the PLL section shown in FIG. 4 is also necessary as a component, but the description is omitted for simplification of the drawing. In this embodiment, an input circuit 255, a multiplex decoder 265, a multiplex encoder 258, and an output circuit 257 are added to the embodiment shown in FIG.

  FIG. 5 is characterized by having a function of transmitting data from the TV 12 to the STB 11 instead of from the STB 11 to the TV 12 when sending data using the clock line. In the initial state, the output circuit 257 is in an OFF state, and data and a clock are transmitted from the transmission unit 240 of the STB 11 to the reception unit 260 as in the embodiment shown in FIG. After the start of the clock extraction operation for each data, the data can be transmitted through the clock line. At this timing, after the output circuit 244 is turned off, the operation of the output circuit 257 is started, and data is sent back from the receiving unit 260 to the transmitting unit 240. At this time, if the clock cycle is set to the same clock cycle as that in the initial state, the clock extraction can be performed in the same manner as other data lines even in the reversely sent clock line. Of course, while the data is being sent back on the clock line, the video data is continuously sent from the transmission unit 240 to the reception unit 260 on the data line.

  FIG. 6 shows an example of the flow of a video signal in the case where this reverse data transmission function is used in the system configuration shown in FIG. The TV 12 sends the compressed video signal recorded in the storage unit 128 to the STB 11 by data transmission in the reverse direction using this clock line, and the TS / PS conversion unit 112 and the decoding unit 113 of the STB 11 decode it into an uncompressed video signal. Then, it can be sent back to the TV 12 through the data line, and a video based on the decoded video signal can be displayed on the display unit 129. Further, if it is necessary to display the OSD recorded in the storage unit, it may be similarly sent to the OSD circuit of the STB 11 through the clock line, and the video composition unit 114 may composite the video with the uncompressed video signal and send it to the TV 12.

  With this function, a video signal recorded in the storage unit can be reproduced and displayed even on a TV without a decoding unit. The same applies to a TV having a decoding unit when the decoding unit does not support the encoding method used for compressed video. Furthermore, even when high-compression broadcasting using a new encoding method that did not exist at the time of TV release has started, there is an advantage that the TV recording function and time shift viewing function can be used. In addition to encoding, even if a compressed video that uses a copyright protection method not supported by TV is recorded on TV, if the STB is compatible with that method, the video is recorded. The compressed video signal may be sent to the STB to perform copyright protection processing and decryption processing. In the same manner as described above, the video signal that has been subjected to the copyright protection process and the decryption process is sent back to the TV side as an uncompressed video signal, whereby a video based on the video signal can be displayed.

  Next, FIG. 7 shows an example of the circuit configuration of the input circuits 254 and 255 and the output circuits 244 and 257 shown in FIG. Prior to the description of FIG. 7, a basic configuration example of the input circuit and the output circuit is shown in FIG. The output circuit 31 includes an output control unit 311, transistors 312 and 313, and a constant current source 314. The input circuit 32 includes termination resistors 336 and 337 and a differential determination unit 338.

  The output control unit 311 switches the ON / OFF operation of the transistors 312 and 313 so as to be a combination of (ON-OFF) or (OFF-ON). At the time of (ON-OFF), the same current as the constant current source 314 flows through the signal line 321 and a voltage is generated at both ends of the termination resistor 336. Since no current flows through the signal line 322, the voltage across the termination resistor 337 is 0. It becomes. At the time of (OFF-ON), since no current flows through the signal line 321, the voltage across the termination resistor 336 is 0, and the same current as the constant current source 314 flows through the signal line 322, generating a voltage across the termination resistor 337. . This is so-called differential transmission. The differential discrimination unit 338 detects the potential difference between the termination resistors to determine the logic level.

  The configuration of FIG. 7 is a configuration in which the configurations of the input circuit and the output circuit shown in FIG. 8 are used as they are and connected in parallel. Since the two output circuits connected in parallel cannot be operated at the same time, the output control unit 331 (or 311) of the output circuit that is not in the operating state turns off the transistors 312 and 313 (or transistors 332 and 333) (OFF-OFF). Control to be Both input circuits may be in the operating state, or the terminating resistors 316 and 317 (or 336 and 337) on the unused side may be disconnected. In addition, the operation of the differential determination unit 318 (or 338) may be stopped to reduce power consumption.

  FIG. 9 is a block diagram showing another embodiment of the present invention, in which two TVs 15 and 16 are used as video processing apparatuses. That is, the present embodiment is an example in which the STB 11 shown in FIG. 1 has a display unit and becomes a TV. Similar to the embodiment shown in FIG. 1, a multiplexed video signal obtained by multiplexing an uncompressed video signal and a compressed video signal is sent from the TV 15 to the TV 16 through the video interface 104, and the uncompressed video signal is displayed on the display unit 129 of the TV 16. Is displayed. On the other hand, the compressed video is recorded by the storage unit 128, reproduced at a time desired by the user, and displayed on the display unit 129.

  One configuration example of the transmission / reception units 157 and 167 is shown in FIG. In this example, both the data line 271 and the clock line 274 are capable of bidirectional transmission. Specific configurations of the input circuit and the output circuit may be the same as those in FIG. When data is transmitted from the transmission / reception unit 157 to the 167, the data is supplied from the multiplex coding unit 231 to the input circuit 251 and the multiplex decoding unit 261 via the output circuit 241. On the other hand, the clock signal is supplied from the clock supply unit 235 to the input circuit 254 and the PLL 283 through the output circuit 244. Conversely, when data is transmitted from the transmission / reception units 167 to 157, the data is supplied from the multiplex coding unit 282 to the input circuit 271 and the multiplex decoding unit 272 via the output circuit 281. On the other hand, the clock signal is transmitted from the clock supply unit 284 to the input circuit 255 and the PLL 274 via the output circuit 257.

  As described above, if the TV 15 or 16 has a function of transmitting a video signal in reverse, the operation is as follows. That is, as indicated by a broken line in FIG. 9, the compressed video recorded by the storage unit 128 of the TV 16 is sent to the TV 15, an uncompressed video signal is formed by the TS / PS conversion unit 152 and the decoding unit 153 of the TV 15, and the display unit 159 Can be displayed. Of course, an uncompressed video signal may be formed by the TS / PS conversion unit 122 and the decoding unit 123 of the TV 16 and then transmitted to the TV 15 and displayed on the display unit 159.

  According to the present embodiment, various resources for digital tuner, storage unit, decoding unit and copyright protection can be interchanged between two TVs (video processing devices) connected to each other.

  In the above embodiments, STB and TV are shown as video processing apparatuses, but the same effect can be expected by combining a video signal source such as a recorder or a DVD player, or a monitor.

  If the embodiment of the present invention described in detail above is used, a non-packet real-time uncompressed video signal and a packetized compressed video signal can be simultaneously transmitted to one interface. That is, it is possible to transmit a plurality of digital video signals in accordance with different standards through one interface. In a video processing apparatus such as a TV using the same, an uncompressed video signal from a signal source such as an STB is displayed in real time on a display unit of the TV, and a compressed video signal transmitted at the same time is included in the TV. It is possible to record in another storage device and view it at another time. That is, both real-time video and time-shifted video of a certain video content can be displayed simultaneously on one screen, and both real-time viewing and time-shifted viewing of the video content are possible.

  Furthermore, by using the physical layer capable of high-speed transmission of the uncompressed video transmission interface for data transmission, when transmission of uncompressed video signals is unnecessary, transmission of many compressed video signals and video transmission in a short time There is also an effect that becomes possible.

  Furthermore, according to the above-described embodiment, it is possible to appropriately cope with various copyright protection technologies, and there is an effect that it is possible to realize good viewing within fair use conditions.

  The present invention is applied to a video signal transmission method for multiplexing and transmitting an uncompressed video signal and a compressed video signal with one interface. This is particularly effective when video signals are transmitted and received between video processing devices, for example, between a video signal source such as an STB and a video display device such as a TV.

  DESCRIPTION OF SYMBOLS 11 ... STB, 12 ... TV, 14 ... Mobile viewer, 31 ... Output circuit, 32 ... Input circuit, 33-34 ... Input / output circuit, 101-102 ... RF signal, 103-104 ... Video signal interface, 111-121 ... Digital tuner, 112-122 ... TS / PS converter, 113, 123, 133 ... Decoder, 114, 124 ... Video composition part, 115, 125 ... OSD part, 116, 126 ... Control part, 117, 230, 240 ... Transmission unit, 127, 250, 260 ... reception unit, 128, 138 ... storage unit, 129, 139 ... display unit, 130 ... code conversion unit, 131, 132 ... interface unit, 211, 212, 213 ... packet generation unit, 214 224: Buffer, 215: ECC encoding unit, 216 ... Interleaving unit, 217 ... Multiple encoding unit, 218 ... Output Circuit, 219 ... Capability identification unit, 220, 230 ... Communication circuit, 221 to 223 ... Packet decoding unit, 225 ... ECC decoding unit, 226 ... Deinterleave unit, 227 ... Multiplex decoding unit, 228 ... Input circuit, 229 ... Capability Transmission unit, 231 to 234, 258, 282 ... Multiple encoding unit, 241 to 244, 257 ... Output circuit, 235, 284 ... Clock supply unit, 251-255 ... Input circuit, 256, 274, 283 ... PLL unit, 261 265, 272 ... Multiplex decoding unit, 311, 331 ... Output control unit, 312-313, 332-333 ... Transistor, 314, 334 ... Current source, 316-317, 337-336 ... Termination resistor, 318, 338 ... Difference Motion discriminating unit 401 ... Multiplexing unit 402 ... Copy flag adding unit 403 ... Cryptographic processing unit 404 ... Transmission coding unit 411 Transmission code decoding section 412 ... decryption unit, 413 ... copy flag extraction unit, 414 ... separating portion

Claims (13)

In the video signal processing device,
An interface unit having at least a function of inputting a compressed video signal from another device and a function of outputting an uncompressed video signal to the other device;
A first processing unit that performs a decryption process of the copyright protection process on a compressed video signal that has been copyright-protected by the first method, input to the interface unit;
A decoder that decodes the compressed video signal decoded by the first processing unit to generate an uncompressed video signal;
A second processing unit that performs copyright protection processing on the uncompressed video signal generated by the decoder by a second method;
The video signal processing apparatus, wherein the interface unit outputs an uncompressed video signal subjected to copyright protection processing by the second processing unit to the other device. The video signal processing apparatus according to claim 1,
The interface unit includes an input / output function unit and an output function unit for video signals,
A video signal processing device, wherein the input / output function unit inputs a compressed video signal from the other device, and the output function unit outputs an uncompressed video signal to the other device. The video signal processing apparatus according to claim 2,
A receiving unit for receiving the compressed video signal;
The decoder decodes the compressed video signal received by the receiving unit to generate an uncompressed video signal,
The interface unit, the output through the input and output function unit, output through the output function of the non-compressed video signal that is decrypted generate compressed video signal received by said decoder of compressed video signal received When the video signal processing apparatus, characterized in that it is possible. The video signal processing apparatus according to any one of claims 1 to 3,
The interface unit can perform a compressed video signal output process to the other apparatus, a compressed video signal input process from the other apparatus, and a reference clock output process to the other apparatus. A video signal processing apparatus. The video signal processing apparatus according to claim 4,
The video signal processing apparatus according to claim 1, wherein the reference clock serves as a reference for receiving processing of the uncompressed video signal output from the interface unit in the other apparatus. In the video signal processing device,
An interface unit having at least an output function for outputting a compressed video signal copyright-protected in the first method to another device, and an input function for inputting an uncompressed video signal from the other device;
A processing unit that performs a decryption process of the copyright protection process on an uncompressed video signal that has been copyright-protected by the second method, input to the interface unit;
A display unit for displaying the uncompressed video signal decoded by the processing unit,
The uncompressed video signal input from the interface unit is a decryption process and a decryption process of the copyright protection process in the other device with respect to the compressed video signal output from the interface unit and subjected to the copyright protection process by the first method. A video signal processing apparatus, which is an uncompressed video signal that has been processed and copyright-protected in the second apparatus by the second method. The video signal processing apparatus according to claim 6,
The interface unit includes an input / output function unit and an input function unit for video signals,
A video signal processing apparatus, wherein the input / output function section outputs a compressed video signal to the other apparatus, and the input function section inputs an uncompressed video signal from the other apparatus. The video signal processing apparatus according to claim 6 or 7,
A storage unit for storing the compressed video signal;
The interface unit inputs a compressed video signal from the other device,
The storage unit stores the compressed video signal input to the interface unit,
The compressed video signal output from the interface unit is a compressed video signal stored in the storage unit. In a video signal processing method in a video signal processing device that can be connected to another device and has an interface unit,
A step of inputting a compressed video signal copyright-protected by the first method from the other device to the interface unit;
Performing a decryption process of the copyright protection process on the input compressed video signal that has been copyright-protected by the first method;
Decoding a compressed video signal that has been subjected to a decryption process of the copyright protection process to generate an uncompressed video signal;
Performing a copyright protection process on the generated uncompressed video signal by a second method;
And a step of outputting an uncompressed video signal copyright-protected by the second method from the interface unit to the other device. The video signal processing method according to claim 9,
Receiving a compressed video signal;
Decoding the received compressed video signal to generate an uncompressed video signal;
Received compressed video signal and output through the input and output functions of the interface unit, the image of the steps of the production uncompressed video signal is output via an output function unit of the interface unit, characterized in that it comprises a Signal processing method. In a video signal processing method in a video signal processing device that can be connected to another device and has an interface unit,
Outputting a compressed video signal copyright-protected in the first scheme from the interface unit to the other device;
A step of inputting a non-compressed video signal copyright-protected by the second method from the other device to the interface unit;
Performing a decryption process of the copyright protection process on the input uncompressed video signal that has been copyright-protected by the second method;
A step of displaying an uncompressed video signal that has been subjected to a decryption process of the copyright protection process,
The uncompressed video signal input from the interface unit is a decryption process and a decryption process of the copyright protection process in the other device with respect to the compressed video signal output from the interface part and copyright-protected by the first method. A video signal processing method comprising: a non-compressed video signal that is processed and copyright-protected in the second apparatus by the second method. The video signal processing method according to claim 11,
A storage step of storing the compressed video signal input to the interface unit from the other device;
The compressed video signal output from the interface unit is the compressed video signal stored in the storing step. In a video signal processing method in a system in which a first interface unit of a first video signal processing device and a second interface unit of a second video signal processing device are connected,
Outputting a compressed video signal copyright-protected by the first method from the first interface unit;
The second interface unit receiving an input of a compressed video signal copyright-protected in the first method;
In the second video signal processing device, a step of decrypting the copyright protection process on the compressed video signal that has been copyright-protected by the first method;
In the second video signal processing device, the compressed video signal that has been decoded is decoded,
Generating an uncompressed video signal;
In the second video signal processing apparatus, a copyright protection process is performed on the generated uncompressed video signal by a second method;
Outputting an uncompressed video signal copyright-protected by the second method from the second interface unit;
The first interface unit receiving an input of an uncompressed video signal copyright-protected in the second method;
In the first video signal processing device, a step of decrypting the copyright protection processing on the uncompressed video signal copyright-protected by the second method;
And displaying the uncompressed video signal that has been decoded in the first video signal processing apparatus.

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