阅读说明：本技术 影音接口的控制信号传输电路及控制信号接收电路 (Control signal transmission circuit and control signal receiving circuit of audio-visual interface ) 是由 宋廉祥 张文林 杨尚原 叶梓民 于 2020-05-19 设计创作，主要内容包括：本申请公开了一种影音接口的控制信号传输电路及控制信号接收电路。控制信号传输电路包含影音接口编码器、信号封装电路,以及数据分配器。影音接口编码器用来接收音频封包,并支持使用者定义封包格式。信号封装电路用来接收第一控制信号,并且根据该用户定义封包格式将该第一控制信号封装成控制数据封包。数据分配器用来接收视频数据及第二控制信号,并且用来混合该第二控制信号与该视频数据,以产生混合数据封包。该影音接口编码器根据影音传输协议封装该控制数据封包、该混合数据封包,以及该音频封包,以产生影音及控制数据。(The application discloses control signal transmission circuit and control signal receiving circuit of audio-visual interface. The control signal transmission circuit comprises an audio-video interface encoder, a signal packaging circuit and a data distributor. The audio-video interface encoder is used for receiving the audio packet and supporting a user to define a packet format. The signal packaging circuit is used for receiving a first control signal and packaging the first control signal into a control data packet according to the user-defined packet format. The data distributor is used for receiving video data and a second control signal and mixing the second control signal and the video data to generate a mixed data packet. The audio-video interface encoder encapsulates the control data packet, the mixed data packet, and the audio packet according to an audio-video transmission protocol to generate audio-video and control data.)

1. A control signal transmission circuit of an audio-visual interface is characterized in that the control signal transmission circuit comprises:

the video and audio interface encoder is used for receiving the video packet and the audio packet and supporting a user to define a packet format; and

the signal packaging circuit is coupled with the audio-video interface encoder and used for receiving a control signal and packaging the control signal into a control data packet according to the user-defined packet format;

the video interface encoder encapsulates the control data packet, the video packet and the audio packet according to a video transmission protocol to generate video and control data.

2. The video audio interface control signal transmission circuit of claim 1, wherein the control signal comprises a backlight control signal and a panel correction signal.

3. The video interface control signal transmission circuit of claim 1, wherein the video interface encoder is an encoder of a high-definition multimedia interface or an encoder of a DisplayPort interface.

4. A control signal receiving circuit of an audio-visual interface is characterized by comprising:

the video-audio interface decoder supports a user-defined packet format, is used for receiving video-audio and control data, and decapsulates the video-audio and control data according to a video-audio transmission protocol to generate a control data packet, a video packet and an audio packet; and

and the signal de-encapsulation circuit is coupled with the audio-video interface decoder and used for receiving the control data packet and de-encapsulating the control data packet according to the user defined packet format so as to generate a control signal.

5. A control signal transmission circuit of an audio-visual interface is characterized in that the control signal transmission circuit comprises:

the audio-video interface encoder is used for receiving the audio packet; and

a data distributor coupled to the video-audio interface encoder for receiving video data and control signals and for mixing the control signals with the video data to generate a mixed data packet;

the audio-video interface encoder encapsulates the mixed data packet and the audio packet according to an audio-video transmission protocol to generate audio-video and control data.

6. The video audio interface control signal transmission circuit of claim 5, wherein the data distributor comprises:

a counter for generating a selection signal according to the system frequency;

a multiplexer coupled to the counter for receiving the control signal and the video data and outputting one of the control signal and the video data according to the selection signal; and

a data regenerating and encoding circuit coupled to the multiplexer for combining and encoding the control signal and the video data to generate the hybrid data packet.

7. A control signal receiving circuit of an audio-visual interface is characterized by comprising:

the audio-video interface decoder is used for receiving the audio-video and control data and decapsulating the audio-video and control data according to an audio-video transmission protocol to generate a mixed data packet and an audio packet; and

and the data de-distributor is coupled with the audio-video interface decoder and used for receiving the mixed data packet and decoding the mixed data packet to generate video data and a control signal.

8. The video audio interface control signal receiving circuit of claim 7, wherein the data de-distributor comprises:

a data decoding and distributing circuit for decoding the mixed data packet to generate a mixed signal, wherein the mixed signal comprises the control signal and the video data;

a counter for generating a selection signal according to the system frequency; and

a demultiplexer, coupled to the counter and the data decoding and distributing circuit, for receiving the mixing signal and outputting one of the control signal and the video data according to the selection signal.

9. A control signal transmission circuit of an audio-visual interface is characterized in that the control signal transmission circuit comprises:

the audio-video interface encoder is used for receiving the audio packet and supporting a user to define a packet format;

the signal packaging circuit is coupled with the audio-video interface encoder and used for receiving a first control signal and packaging the first control signal into a control data packet according to the user-defined packet format;

a data distributor coupled to the video-audio interface encoder for receiving video data and a second control signal, and for mixing the second control signal with the video data to generate a mixed data packet;

the audio-video interface encoder encapsulates the control data packet, the mixed data packet and the audio packet according to an audio-video transmission protocol to generate audio-video and control data.

10. A control signal receiving circuit of an audio-visual interface is characterized by comprising:

the audio-video interface decoder supports a user-defined packet format, is used for receiving audio-video and control data, and decapsulates the audio-video and control data according to an audio-video transmission protocol to generate a mixed data packet, a control data packet and an audio packet;

a signal decapsulation circuit, coupled to the audio-video interface decoder, for receiving the control data packet and decapsulating the control data packet according to the user-defined packet format to generate a first control signal; and

and the data de-distributor is coupled with the audio-video interface decoder and used for receiving the mixed data packet and decoding the mixed data packet to generate video data and a second control signal.

Technical Field

The present invention relates to a digital video interface, and more particularly, to a control signal transmission circuit and a control signal receiving circuit of a digital video interface.

Background

Fig. 1 shows a conventional display (e.g. a television). The display 100 includes a display control chip 110, a panel 120, and a panel control circuit 125. The panel control circuit 125 is used for controlling the display of the panel 120, including the display content (i.e., image data) and the backlight. The display control chip 110 is electrically connected to the panel control circuit 125 through the flat cable C1 and the flat cable C2. The flat cable C1 is used to transmit video signals (i.e., video data), and the flat cable C2 is used to transmit control signals (i.e., control data). The control signal is, for example, a backlight control signal. Generally, the length of the flat cable C2 for transmitting the control signal is limited, so that the distance between the display control chip 110 and the panel control circuit 125 cannot be too large, thereby limiting the design flexibility of the multimedia device.

Disclosure of Invention

In view of the shortcomings of the prior art, an object of the present invention is to provide a control signal transmission circuit of an audio/video interface and a control signal receiving circuit of an audio/video interface, so as to increase the design flexibility of a multimedia device.

The invention discloses a control signal transmission circuit of an audio-visual interface, which comprises an audio-visual interface encoder and a signal packaging circuit. The video-audio interface encoder is used for receiving video packets and audio packets and supporting a user-defined packet format. The signal packaging circuit is coupled with the video-audio interface encoder and used for receiving the control signal and packaging the control signal into a control data packet according to the user-defined packet format. The video interface encoder encapsulates the control data packet, the video packet, and the audio packet according to a video transport protocol to generate video and control data.

The invention also discloses a control signal receiving circuit of the audio-visual interface, which comprises an audio-visual interface decoder and a signal decapsulation circuit. The AV interface decoder supports a user-defined packet format for receiving AV and control data and decapsulating the AV and control data according to an AV transport protocol to generate a control data packet, a video packet, and an audio packet. The signal de-encapsulation circuit is coupled with the audio-visual interface decoder and used for receiving the control data packet and de-encapsulating the control data packet according to the user defined packet format to generate a control signal.

The invention also discloses a control signal transmission circuit of the audio-video interface, which comprises an audio-video interface encoder and a data distributor. The audio-video interface encoder is used for receiving the audio packets. The data distributor is coupled to the video interface encoder, receives video data and a control signal, and mixes the control signal with the video data to generate a mixed data packet. The audio-video interface encoder encapsulates the mixed data packet and the audio packet according to an audio-video transmission protocol to generate audio-video and control data.

The invention also discloses a control signal receiving circuit of the audio-visual interface, which comprises an audio-visual interface decoder and a data de-distributor. The audio-video interface decoder is used for receiving the audio-video and control data and decapsulating the audio-video and control data according to an audio-video transmission protocol to generate a mixed data packet and an audio packet. The data de-distributor is coupled with the video interface decoder and used for receiving the mixed data packet and decoding the mixed data packet to generate video data and control signals.

The invention also discloses a control signal transmission circuit of the audio-video interface, which comprises an audio-video interface encoder, a signal packaging circuit and a data distributor. The audio-video interface encoder is used for receiving the audio packet and supporting a user to define a packet format. The signal packaging circuit is coupled with the audio-video interface encoder and used for receiving a first control signal and packaging the first control signal into a control data packet according to the user-defined packet format. The data distributor is coupled to the video interface encoder, receives video data and a second control signal, and mixes the second control signal with the video data to generate a mixed data packet. The audio-video interface encoder encapsulates the control data packet, the mixed data packet, and the audio packet according to an audio-video transmission protocol to generate audio-video and control data.

The invention also discloses a control signal receiving circuit of the audio-visual interface, which comprises an audio-visual interface decoder, a signal de-encapsulation circuit and a data de-distributor. The AV interface decoder supports a user-defined packet format for receiving AV and control data and decapsulating the AV and control data according to an AV transport protocol to generate a hybrid data packet, a control data packet, and an audio packet. The signal de-encapsulation circuit is coupled with the audio-visual interface decoder and used for receiving the control data packet and de-encapsulating the control data packet according to the user defined packet format to generate a first control signal. The data de-distributor is coupled with the video interface decoder and used for receiving the mixed data packet and decoding the mixed data packet to generate video data and a second control signal.

The control signal transmission circuit of the audio-visual interface and the control signal receiving circuit of the audio-visual interface can transmit or receive the control signal through the connecting wire or cable of the audio-visual interface (such as a high-quality multimedia interface cable or a DisplayPort cable). Compared with the prior art, the multimedia device can enlarge the distance between the display control chip and the panel control circuit, thereby improving the design flexibility of the multimedia device. In this way, the display control chip and the panel control circuit can be disposed in two different devices (for example, a host and a screen, respectively), and control signals are transmitted between the two devices through a connection line or a cable of the audio-visual interface.

The features, operation and efficacy of the present invention are described in detail in the following description of the preferred embodiments with reference to the accompanying drawings.

Drawings

FIG. 1 shows a conventional display;

FIG. 2 is a functional block diagram of a control signal transmission circuit of an audio/video interface according to an embodiment of the present invention;

FIG. 3 is a functional block diagram of a control signal receiving circuit of an audio/video interface according to an embodiment of the present invention;

FIG. 4 is a block diagram of a control signal transmission circuit of an audio/video interface according to another embodiment of the present invention;

FIG. 5 is a functional block diagram of one embodiment of a data distributor 310;

FIG. 6 is a functional block diagram of a control signal receiving circuit of an audio/video interface according to an embodiment of the present invention;

FIG. 7 is a functional block diagram of one embodiment of a data de-allocator 360;

FIG. 8 is a block diagram of a control signal transmission circuit of an audio/video interface according to another embodiment of the present invention; and

fig. 9 is a functional block diagram of a control signal receiving circuit of an audio/video interface according to another embodiment of the present invention.

Description of the symbols:

100: display device

110: display control chip

120: panel board

125: panel control circuit

C1, C2: flat cable

200. 300, 400: control signal transmission circuit

210: signal packaging circuit

220: video-audio interface coder

250. 350 and 450: control signal receiving circuit

260: signal de-encapsulation circuit

270: video-audio interface decoder

310: data distributor

312: multi-task device

314. 364: counter with a memory

316: data regenerating and coding circuit

SC: selection signal

CLK: system frequency

360: data de-distributor

362: demultiplexer

366: data decoding and distributing circuit

SM: mixed signal

Ctrl1, Ctrl 2: control signal

Detailed Description

In the present application, technical terms in the following description are used with reference to common terms in the technical field, and some terms are explained or defined in the specification, and the explanation of the some terms is based on the explanation or the definition in the specification.

The disclosure of the present invention includes a control signal transmission circuit and a control signal receiving circuit of an audio-visual interface. Since some components included in the control signal transmission circuit and the control signal receiving circuit of the av interface of the present invention may be known components alone, the following description will omit details of the known components without affecting the full disclosure and the feasibility of the apparatus of the present invention.

Fig. 2 is a functional block diagram of a control signal transmission circuit of an audio/video interface according to an embodiment of the present invention. The control signal transmission circuit 200 includes a signal packaging circuit 210 and an audio/video interface encoder 220. In some embodiments, the HDMI encoder 220 is an HDMI (High Definition Multimedia Interface) or DisplayPort (DP) encoder. According to the specification of the HDMI and the DisplayPort, the HDMI and the DisplayPort allow a circuit designer to define a packet format by himself, so that the circuit designer can transmit packets conforming to the user-defined packet format through the HDMI or the DisplayPort.

The signal encapsulating circuit 210 receives control signals (e.g., panel-related control signals including, but not limited to, a backlight control signal, a panel correction signal, and a timing control (Tcon) signal) generated by a control circuit (e.g., a display control chip, not shown) of the display, and encapsulates the control signals according to a user-defined packet format to generate control data packets. The control signals may be serial or parallel data. The panel correction signal is used for correcting traces caused by uneven brightness of the display. In some embodiments, the signal packaging circuit 210 further comprises a register, memory or storage circuit for storing the control data packet to be transmitted. In other words, in some embodiments, the signal packaging circuit 210 has a function of buffering the control data packet. The operation of encapsulating the control signal according to the user-defined packet format is to add a self-defined header (header) to the control signal, where the self-defined header is different from the headers of other packets with predetermined formats (including but not limited to video packets, audio packets, and auxiliary data packets) defined by the specification of the av interface encoder 220.

The nic encoder 220 receives packets of a user-defined format (i.e., control data packets generated by the signal packing circuit 210) in addition to the packets of the predetermined formats. The video packet is generated by an av processing chip (not shown) or a multimedia processing chip (not shown) encapsulating video data (e.g., image data) according to the specification of the av interface encoder 220. The audio packets are generated by the video processing chip or the multimedia processing chip encapsulating audio data (e.g., audio data) according to the specification of the video interface encoder 220. The auxiliary data packet is generated by the av processing chip or the multimedia processing chip encapsulating the auxiliary data according to the specification of the av interface encoder 220, for example, the auxiliary data may be the specification of the av data and information required by the receiving end to reconstruct the audio frequency. The nic encoder 220 schedules and arbitrates (e.g., encodes and/or arranges the order of packets) the video packets, audio packets, auxiliary data packets, and control data packets according to the specification to generate the video and control data. Scheduling and arbitration according to the specification of the multimedia interface are well known to those skilled in the art, and therefore will not be described in detail.

Fig. 3 is a functional block diagram of a control signal receiving circuit of an audio/video interface according to an embodiment of the present invention. The control signal receiving circuit 250 includes a signal decapsulating circuit 260 and an av interface decoder 270. The av interface decoder 270 is connected to the av interface encoder 220 through a corresponding connection line or cable (e.g., an hdmi cable or a DisplayPort cable), and receives av and control data through the connection line or cable. In some embodiments, the av interface decoder 270 is a high-definition multimedia interface decoder or a DisplayPort interface decoder. The av interface decoder 270 processes (e.g., decodes and/or decapsulates) the av and control data according to the specification to extract the video packets, audio packets, auxiliary data packets, and control data packets. The video interface decoder 270 may also be referred to as a data recovery circuit (data recovery circuit). The video packet, the audio packet, and the auxiliary data are processed (e.g., decapsulated) by the video circuit, the audio circuit, and the auxiliary data processing circuit, respectively, to obtain the video data, the audio data, and the auxiliary data therein. The control data packet is processed by the signal decapsulation circuit 260.

The signal decapsulation circuit 260 is coupled or electrically connected to the av interface decoder 270, and is configured to decapsulate the control data packet according to a packet format defined by a user to generate a control signal. In other words, as long as the control signal transmitting circuit 200 (i.e., the transmitting end of the multimedia data) and the control signal receiving circuit 250 (i.e., the receiving end of the multimedia data) determine the user-defined packet format in advance, the control signal receiving circuit 250 can smoothly decapsulate the control data packet and obtain the control signal. In this way, a panel control circuit (not shown in fig. 3, for example, the panel control circuit 125 in fig. 1) of the receiving end (including the display or the panel) can control the backlight and/or the calibration panel according to the control signal. The control signals may be serial or parallel data.

Fig. 4 is a functional block diagram of a control signal transmission circuit of an audio/video interface according to another embodiment of the present invention. The control signal transmission circuit 300 includes a data distributor (data allocator)310 and an av interface encoder 220. The data distributor 310 receives video data and control signals, and mixes the video data and the control signals to generate a mixed data packet. More specifically, the video datagram includes a plurality of frames (frames), and each frame includes a plurality of line data, and the data distributor 310 places or inserts the control signal in a blank region (including a Horizontal Front Porch (HFP) and/or a Horizontal Back Porch (HBP)) between the line data and the line data, or a blank region (including a Vertical Front Porch (VFP) and/or a Vertical Back Porch (VBP)) between the frame and the frame. Therefore, the mixed data packet includes video data and control signals. The mixed data packet is transmitted in the form of a video packet, i.e., the av encoder 220 regards the mixed data packet as a video packet. The nic encoder 220 schedules and arbitrates the audio packets, auxiliary data packets, and mixed data packets according to the specification to generate audio and video and control data. The control signals may be serial or parallel data.

In some embodiments, the data distributor 310 places the control signal of the next (n +1 th, n is a positive integer) frame in the blank area (including HFP, HBP and/or VBP) of the current (n) frame.

Fig. 5 is a functional block diagram of one embodiment of a data distributor 310. The data distributor 310 includes a multiplexer 312, a counter 314, and a data regenerating and encoding circuit 316. The multiplexer 312 receives the control signal and the video data, and outputs the control signal or the video data according to the selection signal SC generated by the counter 314. In some embodiments, the counter 314 includes a pixel counter (not shown) and a line counter (not shown), which count according to the system clock CLK. The counter 314 knows the start and end of a line of data based on the count of the pixel counter and the start and end of a frame based on the count of the line counter. The counter 314 controls the multiplexer 312 to output the control signal between the row data and the column data or between the frame and the frame. For example, if the control signal is to be placed or inserted in a blank area between row data and row data, the counter 314 controls the multiplexer 312 to output the control signal between the end of one row of data and the start of the next row of data, while controlling the multiplexer 312 to output video data at other times. For another example, if the control signal is to be placed or inserted in a blank region between a frame and a frame, the counter 314 controls the multiplexer 312 to output the control signal between the end of one frame and the start of the next frame, and controls the multiplexer 312 to output the video data at other times.

The data regenerating and encoding circuit 316 combines the control signal and the video data according to the received sequence, and encapsulates and/or encodes the control signal and the video data into a mixed data packet. The mixed data packet has the same format as a video packet containing only video data, but has a different data amount. More specifically, when the control signal is placed or inserted in a blank area between the column data and the row data, the amount of the column data is redefined such that the amount of the column data of the redefined mixed data packet is greater than the amount of the row data of the video packet including only the video data. When the control signal is placed or inserted into the blank area between the frame and the frame, the frame data amount of the mixed data is redefined, so that the frame data amount of the redefined mixed data packet is larger than that of the video packet only containing the video data.

Fig. 6 is a functional block diagram of a control signal receiving circuit of an audio/video interface according to an embodiment of the present invention. The control signal receiving circuit 350 includes a data de-allocator (data de-allocator) 360 and an av interface decoder 270. The av interface decoder 270 is connected to the av interface encoder 220 through a corresponding connection line or cable (e.g., an hdmi cable or a DisplayPort cable), and receives av and control data through the connection line or cable. The av interface decoder 270 processes (e.g., decodes and/or decapsulates) the av and control data according to the specification to extract the audio packets, auxiliary data packets, and mixed data packets. The hybrid data packet is processed by the data de-distributor 360 to extract the control signal and the video data therein. In this way, a panel control circuit (not shown in fig. 6, for example, the panel control circuit 125 in fig. 1) of the receiving end (including the display or the panel) can control the backlight and/or the calibration panel according to the control signal. The control signals may be serial or parallel data.

Fig. 7 is a functional block diagram of one embodiment of a data de-allocator 360. The data de-distributor 360 includes a demultiplexer 362, a counter 364, and a data decoding and distributing circuit 366. The data decoding and distributing circuit 366 decodes the mixed data packet and outputs a mixed signal SM, where the mixed signal SM includes a control signal and video data. In some embodiments, the counter 364 includes a pixel counter (not shown) and a line counter (not shown), which count according to the system clock CLK. The counter 364 knows the start and end of a line of data based on the count of the pixel counter and the start and end of a frame based on the count of the line counter. The demultiplexer 362 outputs the control signal or the video data in the mix signal SM according to the selection signal SC generated by the counter 364. The operation of demultiplexer 362 is the reverse operation of multiplexer 312 in FIG. 5, and details are well known to those skilled in the art and thus are not described herein.

In some embodiments, the control signal receiving circuit 350 utilizes a timing recovery (timing recovery) technique to synchronize the system clock CLK at the receiving end with the system clock CLK at the transmitting end.

Fig. 8 is a functional block diagram of a control signal transmission circuit of an audio/video interface according to another embodiment of the present invention. The control signal transmission circuit 400 includes a signal packaging circuit 210, a data distributor 310, and an av interface encoder 220. The control signal transmitting circuit 400 is a combination of the control signal transmitting circuit 200 and the control signal transmitting circuit 300. In the embodiment of fig. 8, the signal encapsulation circuit 210 and the data distributor 310 receive and process different control signals. For example, the control signal Ctrl1 is one of a backlight control signal and a panel correction signal, and the control signal Ctrl2 is the other. In other words, the control data packet includes one of the backlight control signal and the panel correction signal, and the mix data packet includes the other.

Fig. 9 is a control signal receiving circuit corresponding to fig. 8. Control signal receiving circuit 450 includes signal decapsulating circuit 260, data de-distributor 360, and av interface decoder 270. The signal decapsulation circuit 260 outputs one of the backlight control signal and the panel correction signal, and the data de-distributor 360 outputs the other.

As shown in fig. 8 and 9, the embodiments of fig. 8 and 9 place different control signals at different positions in the audio/video and control data, that is, transmit and receive different control signals using different signal formats. The control signal receiving circuit 250 of fig. 3 and the control signal receiving circuit 350 of fig. 6 can distinguish the control signal Ctrl1 and the control signal Ctrl2 according to signal content (such as a header, but not limited thereto). In the embodiments of fig. 8 and 9, the control signal receiving circuit 450 can distinguish the control signal Ctrl1 and the control signal Ctrl2 according to the format (i.e., determining whether the control signal is carried by the hybrid data packet or the control data packet) or the source (i.e., output from the signal decapsulating circuit 260 or output from the data de-distributor 360) of the control signal.

Although the backlight control signal and the panel correction signal are used as examples in the above embodiments, the present invention is not limited thereto, and those skilled in the art can appropriately apply the present invention to other types of control signals according to the disclosure of the present invention. Although the embodiments described above take the hdmi and DisplayPort as examples, the invention is not limited thereto, and those skilled in the art can appropriately apply the invention to other types of hdmi and hdmi according to the disclosure of the invention.

It should be noted that the shapes, sizes, proportions and the like of the components in the drawings are merely illustrative, which are provided for persons of ordinary skill in the art to understand the present invention, and are not intended to limit the present invention.

Although the embodiments of the present invention have been described above, these embodiments are not intended to limit the present invention, and those skilled in the art can make changes to the technical features of the present invention according to the contents explicitly or implicitly, but all changes can be made within the scope of the present invention.