HDMI network transmission device supporting HDMI built-in audio and analog audio input switching

Abstract

The HDMI network transmission equipment provided by the utility model supports HDMI built-in audio and analog audio input switching, through setting the control logic of the toggle switch and the main control chip, the HDMI built-in audio and the external analog audio input can be freely switched, the audio access demand under different application scenes is satisfied; the interface chip (such as ADV7625) with the audio embedding and de-embedding function is further utilized, the external analog audio is embedded into the HDMI signal after digitization, and the analog audio is restored and output at the receiving end, the audio and video synchronous transmission is guaranteed; and, through converting the HDMI signal embedded with the audio into the HDBT signal and adopting the Cat6 Ethernet wire for transmission, the stable high-definition video audio synchronous transmission of dozens of meters or even hundreds of meters can be effectively supported, and the utility model is suitable for conference rooms, exhibition halls, classrooms and the like.

Description

Technical Field

[0001] This utility model relates to the field of signal transmission technology, and in particular to an HDMI network transmission device that supports switching between HDMI built-in audio and analog audio input. Background Technology

[0002] With the development of high-definition digital video transmission technology, HDMI (High Definition Multimedia Interface) has been widely used in devices such as televisions, projectors, and video conferencing systems, becoming the mainstream video and audio transmission interface. Meanwhile, in certain specific application scenarios, such as conference systems, educational systems, or commercial presentation systems, users wish to connect and embed external audio sources (such as microphones, audio players, etc.) into the HDMI signal to achieve synchronous audio and video transmission. Traditional HDMI transmission devices typically only support built-in audio and cannot flexibly switch to analog audio input, thus limiting the system's applicability and scalability.

[0003] Furthermore, HDMI signals are susceptible to interference and attenuation during long-distance transmission. The industry typically uses HDBT (HDBaseT) technology to convert HDMI signals into network signals, ensuring transmission quality while enabling long-distance transmission. However, most current HDBT transmission devices lack flexibility in audio processing, failing to support dynamic switching between HDMI audio and external analog audio, and also lacking audio embedding and de-embedding control functions.

[0004] In summary, the problems existing in the current technology urgently need to be solved. Utility Model Content

[0005] This invention provides an HDMI network transmission device that supports switching between HDMI built-in audio and analog audio input, thereby overcoming the deficiencies in the prior art and enabling free switching between HDMI built-in audio and external analog audio input to meet the audio access needs of different application scenarios.

[0006] This utility model provides an HDMI network transmission device that supports switching between HDMI built-in audio and analog audio input, including: An HDMI receiver box and an HDMI output box are connected to each other via a network cable. The HDMI receiver box includes an HDMI input interface, an analog audio input interface, an analog-to-digital converter chip, a main control chip, a toggle switch, a first interface chip, and a conversion chip; The HDMI input interface is used to receive HDMI signals from an HDMI signal source; The analog audio input interface is used to receive external analog audio signals; The analog-to-digital converter chip is used to convert analog audio signals into I2S digital audio signals; The first interface chip is used to embed the I2S digital audio signal into the HDMI signal; The conversion chip is used to convert the HDMI signal with embedded audio into an HDBT signal and transmit it to the HDMI output box via a network cable. The toggle switch is connected to the I / O port of the main control chip, and the two ends of the toggle switch are respectively connected to the power supply voltage and ground; The main control chip is used to control whether the first interface chip performs audio embedding operation according to the level state of the toggle switch; The HDMI output box includes a second interface chip, a digital-to-analog converter chip, and an audio output interface; The second interface chip is used to restore the HDBT signal to the HDMI signal and de-embed the audio signal into an I2S digital audio signal; The digital-to-analog converter chip is used to convert the I2S digital audio signal into an analog audio signal; The audio output interface is used to output the analog audio signal.

[0007] According to the present invention, an HDMI network transmission device that supports switching between HDMI built-in audio and analog audio input is provided. The toggle switch is a two-position DIP switch, one end of which is connected to a pull-up resistor to a 3.3V power supply to generate a high-level control signal, and the other end is connected to a pull-down resistor to ground to generate a low-level control signal.

[0008] According to the present invention, an HDMI network transmission device supporting switching between HDMI built-in audio and analog audio input is provided. The main control chip controls whether the first interface chip performs an audio embedding operation based on the level state of a toggle switch, specifically including: When the main control chip detects that the output of the toggle switch is high, it controls the first interface chip to embed the I2S audio signal into the HDMI signal.

[0009] According to the present invention, an HDMI network transmission device that supports switching between HDMI built-in audio and analog audio input is provided, wherein both the HDMI receiver box and the HDMI output box are provided with metal shielding shells to enhance electromagnetic compatibility and anti-interference capabilities.

[0010] According to the present invention, an HDMI network transmission device that supports switching between HDMI built-in audio and analog audio input is provided. The main control chip is an MCU microcontroller, which reads the state of the toggle switch through the GPIO port and controls the working mode of the interface chip.

[0011] According to the present invention, an HDMI network transmission device that supports switching between HDMI built-in audio and analog audio input is provided, wherein the HDMI receiver box and the HDMI output box are connected by a Cat6 Ethernet cable.

[0012] According to the present invention, an HDMI network transmission device that supports switching between HDMI built-in audio and analog audio input is provided. The analog-to-digital converter chip is an analog-to-digital converter that outputs I2S format audio signals and is used to convert the analog signal input from the 3.5mm analog audio interface into an I2S digital audio signal.

[0013] According to the present invention, an HDMI network transmission device that supports switching between HDMI built-in audio and analog audio input is provided. The digital-to-analog converter chip is a digital-to-analog converter that receives I2S digital audio signals and is used to convert the I2S signal output by the second interface chip into an analog audio signal and then output it through the audio output interface.

[0014] According to the present invention, an HDMI network transmission device that supports switching between HDMI built-in audio and analog audio input is provided. The HDMI output box further includes an HDMI output interface for outputting the restored HDMI signal to a display device.

[0015] According to the present invention, an HDMI network transmission device that supports switching between HDMI built-in audio and analog audio input is provided, wherein the chip model of the first interface chip and the second interface chip is ADV7625.

[0016] This utility model provides an HDMI network transmission device that supports switching between HDMI built-in audio and analog audio input. By setting a toggle switch and the control logic of the main control chip, it can freely switch between HDMI built-in audio and external analog audio input to meet the audio access needs of different application scenarios. It also utilizes an interface chip with audio embedding and de-embedding functions (such as ADV7625) to realize the digitization of external analog audio and embedding it into the HDMI signal, and restore and output the analog audio at the receiving end, ensuring synchronous transmission of audio and video. Furthermore, by converting the HDMI signal with embedded audio into an HDBT signal and transmitting it using a Cat6 Ethernet cable, it can effectively support stable high-definition video and audio synchronous transmission over distances of tens or even hundreds of meters, making it suitable for scenarios such as conference rooms, exhibition halls, and classrooms. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is a structural diagram of an HDMI network transmission device that supports switching between HDMI built-in audio and analog audio input, provided by this utility model. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0020] To address the problems in existing technologies, this utility model proposes an HDMI network transmission device that supports switching between HDMI built-in audio and analog audio input, enabling free switching between HDMI built-in audio and external analog audio input to meet the audio access needs of different application scenarios. The following describes this HDMI network transmission device that supports switching between HDMI built-in audio and analog audio input. Figure 1 As shown, including but not limited to: An HDMI receiver box and an HDMI output box are connected to each other via a network cable. The HDMI receiver box includes an HDMI input interface, an analog audio input interface, an analog-to-digital converter chip, a main control chip, a toggle switch, a first interface chip, and a conversion chip; The HDMI input interface is used to receive HDMI signals from an HDMI signal source; The analog audio input interface is used to receive external analog audio signals; The analog-to-digital converter chip is used to convert analog audio signals into I2S digital audio signals; The first interface chip is used to embed the I2S digital audio signal into the HDMI signal; The conversion chip is used to convert the HDMI signal with embedded audio into an HDBT signal and transmit it to the HDMI output box via a network cable. The toggle switch is connected to the I / O port of the main control chip, and the two ends of the toggle switch are respectively connected to the power supply voltage and ground; The main control chip is used to control whether the first interface chip performs audio embedding operation according to the level state of the toggle switch; The HDMI output box includes a second interface chip, a digital-to-analog converter chip, and an audio output interface; The second interface chip is used to restore the HDBT signal to the HDMI signal and de-embed the audio signal into an I2S digital audio signal; The digital-to-analog converter chip is used to convert the I2S digital audio signal into an analog audio signal; The audio output interface is used to output the analog audio signal.

[0021] This embodiment provides an HDMI network transmission device that supports switching between HDMI built-in audio and analog audio input, such as... Figure 1 As shown, it includes an HDMI receiver box and an HDMI output box. The HDMI receiver box and the HDMI output box are connected by a standard Cat6 network cable for transmitting the converted HDBT signal, realizing long-distance transmission of high-definition video and audio signals.

[0022] The HDMI receiver box includes: The HDMI input interface is used to receive HDMI audio and video signals output from external HDMI signal sources (such as set-top boxes, computers, players, etc.). Analog audio input interfaces (such as 3.5mm interfaces or RCA interfaces) are used to receive analog audio signals from external devices (such as microphones, audio players, etc.); An analog-to-digital converter (ADC) chip converts received analog audio signals into I2S digital audio signals; A toggle switch is used to select the audio source. Its two ends are connected to the power supply voltage (e.g., 3.3V) and ground, respectively, and are connected to the main control chip through IO pins. The main control chip (such as an MCU controller) is used to read the level state of the toggle switch and control the audio embedding mode according to the state; The first interface chip is used to embed I2S format audio signals into HDMI video signals; The conversion chip converts the HDMI signal with embedded audio into an HDBT protocol signal and outputs it to the HDMI output box via a network cable.

[0023] During operation, the main control chip monitors the status of the toggle switch in real time. When the toggle switch is high, the main control chip controls the first interface chip to perform an audio embedding operation, embedding the I2S audio signal converted from analog audio into the original HDMI signal. When the toggle switch is low, the system maintains the native audio in the HDMI signal, meaning no external audio is embedded.

[0024] The HDMI output box includes: The second interface chip is used to receive HDBT signals and restore them to standard HDMI signals, while de-embedding the I2S digital audio signals within them. A digital-to-analog converter (DAC) chip converts I2S audio signals into analog audio signals; Audio output interfaces (such as 3.5mm or RCA interfaces) are used to output de-embedded analog audio signals, which can be connected to audio devices such as speakers and amplifiers.

[0025] Through the above technical solution, this utility model realizes the switching between analog audio and HDMI built-in audio, and transmits audio and video signals through network cable. It has the advantages of simple structure, flexible function and stable transmission, and is particularly suitable for application scenarios of long-distance transmission of audio and video signals and flexible control of multiple audio sources.

[0026] As a further optional embodiment, the toggle switch is a two-position DIP switch, with one end connected to a pull-up resistor to a 3.3V power supply to generate a high-level control signal, and the other end connected to a pull-down resistor to ground to generate a low-level control signal.

[0027] In this further optional embodiment, the toggle switch employs a two-position DIP switch design, enabling it to stably output control signals in two states: high and low. One end is connected to a 3.3V power supply via a pull-up resistor, thus outputting a high-level signal when this end is closed; the other end is connected to ground via a pull-down resistor, outputting a low-level signal when this end is closed. This design offers advantages such as simple structure, rapid response, and reliable control, facilitating precise switching between embedded and de-embedded modes, and improving the overall stability of the system and the convenience of user operation. Simultaneously, the pull-up and pull-down resistors effectively prevent the input from floating, further enhancing the system's anti-interference capability and electrical reliability.

[0028] As a further optional embodiment, the main control chip controls whether the first interface chip performs an audio embedding operation based on the level state of the toggle switch, specifically including: When the main control chip detects that the output of the toggle switch is high, it controls the first interface chip to embed the I2S audio signal into the HDMI signal.

[0029] In one optional embodiment, this invention provides an audio / video signal processing device, wherein the main control chip controls whether the first interface chip performs an audio embedding operation based on the level state of a toggle switch. Specifically, the output terminal of the toggle switch is connected to the GPIO pin of the main control chip to indicate whether the user selects to enable the audio embedding function. The main control chip determines the current user setting state by periodically reading the level state of the GPIO pin.

[0030] When the main control chip detects that the toggle switch output is high, it indicates that the user has enabled the audio embedding function. The main control chip then sends a control command to the first interface chip, instructing it to embed the received I2S audio signal into the currently output HDMI signal. The I2S audio signal can be provided by an external audio device, input to the first interface chip via the audio processing module, and the embedded HDMI signal can simultaneously carry video and audio information and be output to a display device or audio playback terminal.

[0031] Correspondingly, when the toggle switch outputs a low level, the main control chip controls the first interface chip not to perform audio embedding operations, and only outputs the original video signal. This optional implementation allows users to enable or disable the audio embedding function with a simple toggle switch, providing good interactivity and flexibility, and is suitable for audio and video processing needs in different application scenarios.

[0032] As a further optional embodiment, both the HDMI receiver box and the HDMI output box are provided with metal shielding shells to enhance electromagnetic compatibility and anti-interference capabilities.

[0033] In this embodiment, both the HDMI receiver box and the HDMI output box are encapsulated using a metal shielding shell. Specifically, the metal shielding shell covers the external structure of the receiver box and the output box, forming an effective electromagnetic shielding layer. This shielding layer can effectively block the influence of external electromagnetic interference (EMI) on the internal circuitry, while reducing the electromagnetic radiation generated by the device itself, thus meeting the requirements of relevant electromagnetic compatibility (EMC) standards.

[0034] By incorporating a metal shielding housing, the device's anti-interference capability is enhanced, improving the stability and reliability of signal transmission and preventing signal distortion or loss caused by electromagnetic noise. This is especially crucial in complex electromagnetic environments, ensuring high-quality transmission of high-definition video and audio signals. Simultaneously, the metal housing also provides excellent heat dissipation, contributing to stable device operation and extending its lifespan.

[0035] As a further optional embodiment, the main control chip is an MCU microcontroller, which reads the state of the toggle switch through the GPIO port and controls the working mode of the interface chip.

[0036] In this embodiment, the main control chip is a microcontroller unit (MCU). This MCU is connected to the toggle switch via its general purpose input / output (GPIO) ports to read the switch's voltage level in real time. During operation, the MCU continuously monitors the signal changes on the GPIO ports. When it detects a toggle switch switching state, the MCU determines the user's selection based on the read high and low voltage signals.

[0037] Based on the state of the toggle switch, the MCU sends corresponding control commands to the first interface chip via the control bus or control signal line to adjust the operating mode of the interface chip and switch whether the audio signal is embedded into the HDMI signal. Through centralized control by the MCU, the system can flexibly respond to user operations and achieve efficient management of the interface chip's functions.

[0038] This implementation fully utilizes the low power consumption, high reliability, and abundant GPIO resources of the MCU to achieve a simple and efficient control scheme, suitable for audio switching control needs in various vehicle and audio / video transmission devices.

[0039] As a further optional embodiment, the HDMI receiver box and the HDMI output box are connected using a Cat6 Ethernet cable.

[0040] In this embodiment, the HDMI receiver box and the HDMI output box are connected using a Cat6 Ethernet cable. This Cat6 cable offers excellent transmission performance and interference resistance, supporting high-speed and stable digital signal transmission to meet the needs of long-distance, high-bandwidth video and audio data transmission.

[0041] By using Cat6 network cables, the system can achieve high-quality long-distance transmission of high-definition video and audio signals, while simplifying the cabling structure and improving installation flexibility and convenience. Furthermore, Cat6 network cables are inexpensive, widely applicable in various network environments, and easy to maintain and replace, enhancing the system's practicality and engineering adaptability.

[0042] As a further optional embodiment, the analog-to-digital converter chip is an analog-to-digital converter that outputs I2S format audio signals, used to convert analog signals input from a 3.5mm analog audio interface into I2S digital audio signals.

[0043] In this embodiment, the digital-to-digital converter (ADC) chip is an analog-to-digital converter (ADC) capable of outputting I2S format digital audio signals. This ADC chip is connected to a 3.5mm analog audio input interface and is used to convert the analog audio signal input through this interface into a digital audio signal conforming to the I2S standard.

[0044] In practical operation, external analog audio signals enter the receiver box through a 3.5mm interface. They are first sampled and digitized by an analog-to-digital converter chip, and the converted I2S digital audio signal is then sent to the first interface chip for embedding processing. Using the I2S format as the digital audio transmission standard ensures high-fidelity and low-latency audio signal transmission, meeting the requirements for synchronized audio and video transmission.

[0045] As a further optional embodiment, the digital-to-analog converter chip is a digital-to-analog converter that receives I2S digital audio signals and is used to convert the I2S signal output by the second interface chip into an analog audio signal and then output it through the audio output interface.

[0046] In this embodiment, the digital-to-analog converter chip is a digital-to-analog converter (DAC) used to receive the I2S digital audio signal output by the second interface chip. This DAC chip converts the received I2S digital audio signal into a high-fidelity analog audio signal, which is then output to an external audio device, such as a speaker or amplifier, through an audio output interface (e.g., a 3.5mm audio jack).

[0047] In its specific operation, the second interface chip de-embeds the I2S format digital audio signal from the received HDBT signal and transmits it to the digital-to-analog converter chip for conversion. By employing a high-performance digital-to-analog converter chip, distortion and noise during the audio signal conversion process are minimized, improving sound quality and meeting the requirements for high-quality audio playback.

[0048] As a further optional embodiment, the first interface chip and the second interface chip are both of the ADV7625 type.

[0049] In this embodiment, both the first interface chip and the second interface chip are ADV7625 chips. The ADV7625 is a high-performance interface chip that integrates high-definition multimedia interface (HDMI) reception and transmission functions, supports audio signal embedding and de-embedding, and has excellent signal processing capabilities and stability.

[0050] Specifically, the ADV7625, acting as the first interface chip, receives the I2S digital audio signal from the analog-to-digital converter chip and embeds it into the HDMI video signal to achieve synchronous audio and video transmission. The ADV7625, acting as the second interface chip, de-embeds the audio signal from the received HDMI signal and outputs it in I2S format for the digital-to-analog converter chip to perform digital-to-analog audio conversion.

[0051] Employing the ADV7625 chip, the system achieves high-quality audio processing and stable signal transmission, supports multiple audio and video formats, and meets diverse application needs. Furthermore, this chip is widely used in professional video transmission equipment, exhibiting excellent compatibility and mature technical support, thus enhancing the reliability and practical value of this invention.

[0052] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. An HDMI network transmission device that supports switching between HDMI built-in audio and analog audio input, characterized in that, include: An HDMI receiver box and an HDMI output box are connected to each other via a network cable. The HDMI receiver box includes an HDMI input interface, an analog audio input interface, an analog-to-digital converter chip, a main control chip, a toggle switch, a first interface chip, and a conversion chip; The HDMI input interface is used to receive HDMI signals from an HDMI signal source; The analog audio input interface is used to receive external analog audio signals; The analog-to-digital converter chip is used to convert analog audio signals into I2S digital audio signals; The first interface chip is used to embed the I2S digital audio signal into the HDMI signal; The conversion chip is used to convert the HDMI signal with embedded audio into an HDBT signal and transmit it to the HDMI output box via a network cable. The toggle switch is connected to the I / O port of the main control chip, one end of the toggle switch is connected to the power supply voltage, and the other end of the toggle switch is grounded; The main control chip is used to control whether the first interface chip performs audio embedding operation according to the level state of the toggle switch; The HDMI output box includes a second interface chip, a digital-to-analog converter chip, and an audio output interface; The second interface chip is used to restore the HDBT signal to the HDMI signal and de-embed the I2S digital audio signal in it; The digital-to-analog converter chip is used to convert the I2S digital audio signal into an analog audio signal; The audio output interface is used to output the analog audio signal.

2. The HDMI network transmission device supporting switching between HDMI built-in audio and analog audio input as described in claim 1, characterized in that, The toggle switch is a two-position DIP switch. One end is connected to a pull-up resistor to a 3.3V power supply to generate a high-level control signal, and the other end is connected to a pull-down resistor to ground to generate a low-level control signal.

3. The HDMI network transmission device supporting switching between HDMI built-in audio and analog audio input as described in claim 1, characterized in that, The main control chip controls whether the first interface chip performs audio embedding operation based on the level state of the toggle switch, specifically including: When the main control chip detects that the output of the toggle switch is high, it controls the first interface chip to embed the I2S digital audio signal into the HDMI signal.

4. The HDMI network transmission device supporting switching between HDMI built-in audio and analog audio input as described in claim 1, characterized in that, Both the HDMI receiver box and the HDMI output box are equipped with metal shielding shells to enhance electromagnetic compatibility and anti-interference capabilities.

5. The HDMI network transmission device supporting switching between HDMI built-in audio and analog audio input as described in claim 1, characterized in that, The main control chip is an MCU microcontroller. The MCU microcontroller reads the level state of the toggle switch through the GPIO port to control the working mode of the interface chip.

6. The HDMI network transmission device supporting switching between HDMI built-in audio and analog audio input as described in claim 1, characterized in that, The HDMI receiver box and the HDMI output box are connected via a Cat6 Ethernet cable.

7. The HDMI network transmission device supporting switching between HDMI built-in audio and analog audio input as described in claim 1, characterized in that, The analog-to-digital converter chip is an analog-to-digital converter that outputs I2S format audio signals, used to convert analog signals input from a 3.5mm analog audio interface into I2S digital audio signals.

8. The HDMI network transmission device supporting switching between HDMI built-in audio and analog audio input as described in claim 1, characterized in that, The digital-to-analog converter chip is a digital-to-analog converter that receives I2S digital audio signals. It is used to convert the I2S signal output by the second interface chip into an analog audio signal and then output it through the audio output interface.

9. The HDMI network transmission device supporting switching between HDMI built-in audio and analog audio input as described in claim 1, characterized in that, The first interface chip and the second interface chip are both ADV7625.

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