JPH0730865A - Video data transmitter, video data receiver and video data transmission device - Google Patents

Abstract

PURPOSE:To sliminate many signal lines interconnecting a transmitter and a receiver in the case of parallel transmission stipulated in the BTA S-002 when video data and auxiliary data are sent by adopting the serial transmission. CONSTITUTION:The system is provided with a color difference data multiplexer circuit 1 multiplexing two color difference data Pb, Pr, a Y channel blanking data multiplexer circuit 2 multiplexing the auxiliary data for the digital blanking period, a Pb/Pr channel blanking data multiplexer circuit 3, a word multiplexer circuit 4 multiplexing outputs of the two blanking data multiplexer circuits and a parallel/serial conversion circuit 5 applying parallel/serial conversion to the output of the word multiplexer circuit 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for transmitting video data or the like as a digital signal, and more particularly to a transmission device for converting parallel video data or the like into serial video data or the like for transmission.

[0002]

2. Description of the Related Art In recent years, there has been a demand for higher quality video, and due to advances in semiconductor technology that supports this, video signals have been digitized as in the case of audio signals, and processing such as signal processing and storage is performed using digital data. There are more and more people being told. In this way, when various processes are performed on digital data, the transmission of these data maintains high quality, and therefore is meaningless unless it is digital transmission. Especially in broadcasting equipment and the like, high quality transmission is required.

Further, in such data transmission between devices, the connection between the devices must be easy. Therefore, the format of data transmitted between devices, the signal level, etc. are specified. As an example of such a regulation, in the case of HDTV signals, BTA (Broadcasting Technology Development Association) S-002
(1125/60 system HDTV video signal encoding and bit parallel interface standard) and the like.

Below, as a conventional example, BTA is defined as a bit parallel interface standard for HDTV signals.
An example of transmitting video data according to S-002 in FIG.
This will be described with reference to FIGS. 4 and 5. Figure 4 shows BTA S-
An example of the configuration of a conventional transmission device when transmitting HDTV video data according to 002 is shown. FIG. 5 shows a configuration example of a conventional receiving device. As shown in FIG. 4, in the transmission device, Y is parallel data obtained by converting the analog luminance signal (Y) into discrete values. Similarly, Pb and Pr are parallel data obtained by converting analog color difference signals (Pb) and (Pr) into discrete values.

The blanking data multiplexing circuit 2 multiplexes the input Y data with a timing reference code including synchronization information during the blanking period and auxiliary data YA such as audio data as necessary and outputs the resulting YD data. . The inputted Pb and Pr data are word-multiplexed by the color difference data multiplexing circuit 1, and then, similarly to the Y data, the blanking data multiplexing circuit 3 performs timing reference code including synchronization information during the blanking period and, if necessary, voice, etc. The auxiliary data CA is multiplexed and output as Pb / PrD data.

FIG. 3 shows a time relationship between digital video data in which an analog video signal and timing reference codes (SAV, EAV) and the like are multiplexed. As shown in FIG. 3, a digital line forming one horizontal period is composed of a digital effective line composed of video data and a digital line blanking corresponding to horizontal blanking. The first (EAV) and last (SAV) words of the digital line blanking are timing reference codes including synchronization information.

Auxiliary data such as voice data can be multiplexed by a method such as a packet format during the digital line blanking period excluding EAV and SAV.
According to BTA S-002, 8 bits or 10 bits of parallel YD data and 8 bits or 10 bits are transmitted from a transmitter.
Bit parallel Pb / PrD data and clock signals corresponding to these parallel data are transmitted.

On the other hand, in the receiving device, the YD data, Pb
/ PrD data and a clock signal are received, the timing reference code multiplexed in the digital line blanking is detected in the blanking data separation circuit 9 from the received YD data, and auxiliary data YA
Is separated and YD data is output. Also received P
Blanking data separation circuit 10 from b / PrD data
The timing reference code is detected by and the auxiliary data CA is separated if necessary. Further, the color difference data separation circuit 11
Are separated into two color difference data of Pb and Pr.

[0009]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention BTA S-0
Although video data can be transmitted by the means defined in No. 02, in order to realize this, a large number of signal lines are required in the transmission path. The BTA S-002 regulations stipulate that twisted pair cables with individual shields be used for signal transmission. Therefore, even if the ground line is removed, 42 signal lines are required for a 10-bit system and 34 signal lines are required for an 8-bit system. Of course, these signal lines are housed in a single composite cable,
It is a thick cable, and has the drawback of being extremely difficult to handle.

The present invention solves this problem, and when transmitting data such as the above-mentioned video data, it is possible to transmit the video data etc. with a single thin cable without requiring a large number of signal lines. To do.

[0011]

In order to achieve the above object, a video data transmitting apparatus of a video data transmitting apparatus of the present invention is a word multiplex for word-multiplexing Y channel parallel data and Pb / Pr channel parallel data. Circuit and parallel / convert word-multiplexed parallel data to serial data
And a serial conversion circuit.

Further, the video data receiving apparatus of the present invention receives the serial data sent from the video data transmitting apparatus and converts the serial data into parallel data, and the serial / parallel conversion circuit. The configuration includes a synchronization detection circuit that controls the conversion timing of the circuit, and a word separation circuit that separates the data converted into parallel data into Y channel parallel data and Pb / Pr channel parallel data.

[0013]

According to the present invention, when the video data or the like is transmitted by the above means, the BTA S-0 is used in the video data transmitting device.
02 parallel data and Pb / P specified in 02
The parallel data of the r channel is word-multiplexed, and the multiplexed data is parallel / serial converted. As a result, a large number of signal lines defined in the conventional BTA S-002 are not necessary, and video data and the like can be transmitted by one signal line. Further, in the video data receiving device, serial data transmitted by one signal line is converted into parallel data.

If the conversion timing is not correct, the parallel data after conversion will have a bit shift, so this timing is controlled by the synchronization detection circuit. Correctly converted parallel data is Y channel parallel data and Pb / Pr.
Separated into parallel data for channels. Since the separated parallel data of the Y channel and the parallel data of the Pb / Pr channel are the data defined by the conventional BTA S-002, the subsequent processing can be performed by the conventional method.

[0015]

Embodiments of the present invention will now be described in detail with reference to the drawings.

(Embodiment 1) An embodiment of the video data transmitting apparatus of the present invention will be described with reference to FIGS. 1, 3, 6, and 7. Digitized video data and, if necessary,
As a method for multiplexing and transmitting auxiliary data such as digitized voice data and control data, B
The TA (Broadcasting Technology Development Council) has established the 1125/60 system HDTV video signal encoding and bit parallel interface standard (BTA S-002). This embodiment will be described based on this standard.

FIG. 1 is a block diagram showing the configuration of the video data transmitting apparatus of this embodiment. The input data Y shown in the drawing is the luminance of the analog HD signal according to the encoding parameter defined by BTA S-002. It is parallel data obtained by converting the signal (Y) into discrete values by an A / D converter or the like. Similarly, Pb and Pr are data obtained by converting the color difference signals (Pb) and (Pr) of the analog HD signal into discrete values.
In BTA S-002, the sampling rate for converting a luminance signal into a discrete value is 74.25 MHz, and the sampling rate for converting a color difference signal into a discrete value is 37.125.
MHz. Of the input signals input to the video data transmission device, Pb and Pr are word-multiplexed by the color difference data multiplexing circuit 1. The word rate of the word-multiplexed parallel data is 74.25 MHz, which is the same as the Y data.

FIG. 3 shows the time relationship between the analog video signal and the digital video data. One horizontal period is defined as a digital line, which is parallel data of the Y channel and Pb / Pr channel word-multiplexed. If the period of the parallel data word rate is 1T, 220
This digital line is called a digital effective line and is a period of video data (1920T).
And a blanking period (280T) called digital line blanking.

In BTA S-002, EAV (END OF) is added at the beginning and end of the digital line blanking period.
ACTIVE VIDEO) and SAV (START)
4 word timing reference data called OFACTIVE VIDEO) is inserted, and video data is not transmitted during the digital line blanking period.
Auxiliary data such as voice data can be multiplexed.

In the Y channel blanking data multiplexing circuit 2 and the Pb / Pr channel blanking data multiplexing circuit 3, writing of EAV and SAV and EAV and SAV are performed.
The auxiliary data YA and CA that have been input to parts other than are multiplexed. Here, the output of the Y channel blanking data multiplex circuit 2 becomes YD data, and the output of the Pb / Pr channel blanking data multiplex circuit 3 is Pb / PrD.
It becomes data. The YD data and Pb / PrD data are parallel data, and this is BTA S-002.
It is the video data of the bit parallel interface specified by.

In the bit parallel interface, in addition to this parallel data, a clock signal of 74.25 MHz corresponding to the word rate of this parallel data is also specified. If the auxiliary data such as voice data is unnecessary, the auxiliary data may not be multiplexed. In this case, the Y channel blanking data multiplexing circuit 2 and the Pb / Pr channel blanking data multiplexing circuit 3 are It becomes unnecessary.

The Y-channel parallel data YD and Pb / Pr channel parallel data Pb /
The PrD data is word-multiplexed by the word multiplexing circuit 4 at the next stage in the procedure as shown in FIG. As shown in FIG. 6, after being word-multiplexed, the parallel data is the data from the Pb / Pr channel and the next data is the data from the Y channel in the digital effective line period. The next is also data from the Pb / Pr channel, which is sequentially and alternately repeated.

In digital line blanking, the first data is data from the Pb / Pr channel, the next data is data from the Y channel, and the next data is Pb, as in the digital effective line period. Data from the / Pr channel, which is sequentially and alternately repeated. As a result, the first digital line blanking after multiplexing is an 8-word EAV.
And the last 8 words are SAV.

The first data of this 8-word EAV is
3FF from the Pb / Pr channel (for 10 bits), the next data is 3FF from the Y channel, and the next data is 000 from the Pb / Pr channel.
(In the case of 10 bits) is multiplexed data, and thereafter, data of two channels are alternately multiplexed in order.

The 8 words of SAV are Pb as well as EAV.
/ Pr channel data and Y channel data are alternately multiplexed in this order. This is shown in FIG. The word-multiplexed parallel data is converted into serial data by the parallel / serial conversion circuit 5. In addition, this serial data is often scrambled and randomized in order to secure timing information and suppress jitter before being normally transmitted. In this case, the parallel / serial conversion circuit 5 can be provided with this function. I can. The serial signal SD output from the video data transmitter may be an electric signal or an optical signal and may be transmitted.

In this embodiment, the case where the signals Y, Pb and Pr obtained by converting the analog luminance signal (Y) and the analog color difference signals (Pb) and (Pr) into discrete values are input is described. The signal may be a signal of a bit parallel interface defined by BTA S-002. In this case, the color difference data multiplexing circuit 1 becomes unnecessary. Further, it may be a signal obtained by converting analog G, B and R signals into discrete values as an input signal. In this case, the color difference data multiplex circuit 1 becomes unnecessary, the blanking data multiplex circuit can be added to each of the G, B, and R channels, and the word multiplex circuit 4 multiplexes the parallel data of three channels of G, B, and R. To do. An example of the multiplex format in this case is shown in FIG.

(Embodiment 2) An embodiment of the video data receiving apparatus of the present invention will be described in detail below with reference to FIG.
The serial signal described in the first embodiment is input to the video data receiving device. The serial data SD input to the video data receiving device is converted into parallel data by the serial / parallel conversion circuit 6. When the serial data is scrambled in the video data transmission device, the descrambling process is performed before converting the serial data into parallel data.

The parallel data output from the serial / parallel conversion circuit 6 is input to the synchronization detection circuit 7 to determine whether the timing of serial / parallel conversion is correct. A signal is sent to the serial / parallel conversion circuit 6 to change it so that bit shift does not occur in the parallel data.

Next, the parallel data output from the serial / parallel conversion circuit 6 is separated into the Y channel data and the Pb / Pr channel data by the word separation circuit 8 in the next stage. The separated Y channel data is further processed by the Y channel blanking data separation circuit 9 to obtain luminance signal data Y.
And auxiliary data YA such as voice data are separated and output. Similarly, the Pb / Pr channel data separated by the word separation circuit 8 is separated by the Pb / Pr channel blanking data separation circuit 10 into color difference signal data Pb / PrD and auxiliary data CA.

The Pb / PrD data is further separated by the color difference data separation circuit 11 into two color difference data Pb and Pr, which are output. When the auxiliary data is unnecessary, the Y channel blanking data separating circuit 9 and the Pb / Pr channel blanking data separating circuit 10 described above are unnecessary.

In this embodiment, the two color difference data are separated and outputted, but the signals of the bit parallel interface defined by BTAS-002 may be outputted without separating them.
In this case, the color difference data separation circuit 11 is unnecessary. When there are three channels G, B and R, the word separation circuit 8 separates the data into the three channels G, B and R. If auxiliary data is present, a blanking data separation circuit is added to each corresponding channel, and the color difference signal separation circuit becomes unnecessary.

(Embodiment 3) Next, an embodiment of the video data transmission apparatus will be briefly described. The video data transmission apparatus of the present embodiment uses the transmission signal output from the video data transmission apparatus having the functions described in the first embodiment and uses the transmission medium such as an optical fiber or a coaxial cable to implement the functions described in the second embodiment. It is configured to be transmitted to the provided video data receiving device. Various configurations can be applied to the configurations of the video data transmitting device and the video data receiving device as in the above-described embodiments.

According to this embodiment, the number of signal lines connecting the video data transmitting device and the video data receiving device can be reduced by the above configuration.

[0034]

As described above, according to the present invention, when transmitting auxiliary data composed of video data, audio data, control data, etc., the number of signal lines between the video data transmitting device and the video data receiving device is significantly increased. It is possible to reduce the number and connect with one optical fiber or one coaxial cable.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a video data transmission device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a video data receiving device according to an embodiment of the present invention.

FIG. 3 is a time relationship diagram of digitized video data and analog video signals.

FIG. 4 is a block diagram of a conventional video data transmission device.

FIG. 5 is a block diagram of a conventional video data receiving device.

FIG. 6 is a data configuration diagram showing a data multiplexing format of a Y, Pb, Pr system.

FIG. 7 is a data configuration diagram showing a data multiplexing format of G, B, and R systems.

[Explanation of symbols]

1 Color difference data multiplex circuit 2 Y channel blanking data multiplex circuit 3 Pb / Pr channel blanking data multiplex circuit 4 Word multiplex circuit 5 Parallel / serial conversion circuit 6 Serial / parallel conversion circuit 7 Sync detection circuit 8 Word separation circuit 9 Y channel Blanking data separation circuit 10 Pb / Pr channel blanking data separation circuit 11 Color difference data separation circuit

Claims (17)

[Claims] 1. A color difference data multiplexing circuit for multiplexing parallel data obtained by converting a color difference signal Pb which is a component signal of an HD analog video signal into a discrete value and parallel data obtained by converting a color difference signal Pr into a discrete value, and an HD analog video signal. , A Y-channel blanking data multiplexing circuit that multiplexes auxiliary data during a digital line blanking period of parallel data obtained by converting the luminance signal Y, which is a component signal, into discrete values, and a digital line of output data from the color difference data multiplexing circuit. Pb / Pr channel blanking data multiplex circuit for multiplexing auxiliary data during the blanking period, and word multiplex circuit for multiplexing output data of the Y channel blanking multiplex circuit and output data of the Pb / Pr channel blanking data multiplex circuit And output from the word multiplexing circuit Video data transmission apparatus characterized by comprising a parallel / serial conversion circuit for converting the parallel data that the serial data. 2. A color difference data multiplexing circuit for multiplexing parallel data obtained by converting a color difference signal Pb which is a component signal of an HD analog video signal into a discrete value and parallel data obtained by converting a color difference signal Pr into a discrete value, and an HD analog video signal. Of the component signal of the luminance signal Y and the output data of the color difference data multiplexing circuit, and a parallel / serial conversion circuit for converting the parallel data output from the word multiplexing circuit into serial data. A video data transmission device characterized by the above. 3. The input signal is BTA (Broadcasting Technology Development Association)
A Y-channel blanking data multiplexing circuit which is a bit parallel interface signal of the Y, Pb / Pr system defined in S-002, and which multiplexes auxiliary data during the digital line blanking period of the luminance signal in the input signal. A Pb / Pr channel blanking data multiplex circuit for multiplexing auxiliary data during a digital line blanking period of color difference signals, output data of the Y channel blanking multiplex circuit and output data of the Pb / Pr channel blanking data multiplex circuit And a parallel / serial conversion circuit for converting parallel data output from the word multiplex circuit into serial data. 4. The input signal is BTA (Broadcasting Technology Development Association)
A bit parallel interface signal of the Y, Pb / Pr system defined in S-002, which includes a word multiplex circuit for multiplexing the color difference signal Pb, the color difference signal Pr, and the luminance signal Y in the input signal, and the word multiplex circuit. A parallel / serial conversion circuit for converting output parallel data to serial data, the video data transmitting device. 5. The word multiplexing circuit is provided with Y during the digital effective line period and the digital line blanking period.
Channel parallel data and Pb / Pr channel parallel data are first Pb / Pr channel data, then Y
5. The video data transmission device according to claim 1, wherein the channel data is sequentially word-multiplexed alternately like the Pb / Pr channel data. 6. The video data transmitting apparatus according to claim 1, wherein the parallel / serial conversion circuit has a scramble function for serial data. 7. An input signal is a bit parallel interface signal of a G, B, R system defined in BTA S-002, a blanking data multiplexing circuit for each of G channel, B channel, R channel, and these 3 channels. And a word multiplexing circuit for word multiplexing the output data of the blanking data multiplexing circuit. 8. A word multiplexing circuit, wherein G channel parallel data, B channel parallel data and R channel parallel data are first G channel data, then B channel data, then R channel data, 8. The video data transmission device according to claim 7, wherein next data is sequentially word-multiplexed like G channel data. 9. A serial / parallel conversion circuit for converting received serial data into parallel data, and a signal for monitoring an output from the serial / parallel conversion circuit and controlling a conversion timing of the serial / parallel conversion circuit. To the serial / parallel conversion circuit, and output data from the serial / parallel conversion circuit to Y-channel parallel data and Pb / Pr.
A word separation circuit that separates into parallel data of channels,
A Y channel blanking data separation circuit for separating auxiliary data from the Y channel parallel data output from the word separation circuit, and Pb for separating auxiliary data from the Pb / Pr channel parallel data output from the word separation circuit. / Pr channel blanking data separation circuit, and a color difference data separation circuit that separates and outputs the output data from the Pb / Pr channel blanking data separation circuit into color difference data corresponding to Pb and color difference data corresponding to Pr. A video data receiving device comprising. 10. A serial / parallel conversion circuit for converting received serial data into parallel data, and a signal for monitoring an output from the serial / parallel conversion circuit and controlling a conversion timing of the serial / parallel conversion circuit. To the serial / parallel conversion circuit, and output data from the serial / parallel conversion circuit to Y-channel parallel data and Pb / P
A word separation circuit for separating the r channel parallel data, and color difference data corresponding to Pb and P from the Pb / Pr channel parallel data output from the word separation circuit.
An image data receiving device, comprising: a color difference data separation circuit for separating and outputting color difference data corresponding to r. 11. A serial / parallel conversion circuit for converting received serial data into parallel data, and a signal for monitoring an output from the serial / parallel conversion circuit and controlling a conversion timing of the serial / parallel conversion circuit. To the serial / parallel conversion circuit, and output data from the serial / parallel conversion circuit to Y-channel parallel data and Pb / P
A word separation circuit for separating the r-channel parallel data, a Y-channel blanking data separation circuit for separating auxiliary data from the Y-channel parallel data output from the word separation circuit, and a Pb output from the word separation circuit. And a Pb / Pr channel blanking data separating circuit for separating auxiliary data from parallel data of the / Pr channel. 12. A serial / parallel conversion circuit for converting received serial data into parallel data, and a signal for monitoring an output from the serial / parallel conversion circuit and controlling a conversion timing of the serial / parallel conversion circuit. To the serial / parallel conversion circuit, and output data from the serial / parallel conversion circuit to Y-channel parallel data and Pb / P
A video data receiving device comprising a word separation circuit for separating parallel data of r channels. 13. A word separation circuit converts Y channel parallel data and Pb / Pr channel parallel data into a Pb / Pr channel data first, a Y channel data next, and a Pb / Pr channel data next. 13. The video data receiving device according to claim 9, wherein the data of each channel is separated from the parallel data which is alternately and sequentially word-multiplexed. 14. The video data receiving device according to claim 9, wherein the serial / parallel conversion circuit has a descrambling function for serial data. 15. A serial / parallel conversion circuit for converting received serial data into parallel data, and word separation for separating an output signal of the serial / parallel conversion circuit into data of three channels of G channel, B channel and R channel. Circuit,
A blanking data separation circuit for each of G channel, B channel, and R channel for separating auxiliary data from each output data of the word separation circuit is provided, and G, B,
A video data receiving device for outputting a bit parallel interface signal of an R system. 16. A word separation circuit sets parallel data of G channel, parallel data of B channel and parallel data of R channel, first G channel data, next B channel data, next R channel data, 16. The video data receiving apparatus according to claim 15, wherein each data is separated from parallel data sequentially word-multiplexed like G channel data. 17. A video data transmitting device according to claim 1 and a video data receiving device according to claim 9, wherein the output of the video data transmitting device is input to the video data receiving device via a transmission line. A video data transmission device characterized by transmission.