Technical Principle, Product Characteristics, and Application of Wireless Video Transmission

In today's digital information age, social development, economic growth, and people's production are increasingly inseparable from the Internet and the application of various scientific and technological means. Various forms of wireless transmission functions are applied in different industries. And wireless video transmission technology has become an essential part of film and television productions. It is a wireless monitoring system that realizes the integrated transmission of sound, digital, and video data using radio waves as the transmission medium. What are its own advantages and principles?

1. Principles of the wireless video transmission system

A wireless video transmission system refers to a monitoring system that uses radio waves to transmit video, sound, data, and other signals without wiring (cables). These devices are very easy to set up and use on-site, free from the constraints of wired connections. At the same time, with the development of wireless technology, it has now been able to ensure the basic requirements of most film and television shooting teams for signal stability and real-time audio and video transmission and has gradually replaced wired transmission equipment with excellent user experience and cost performance.

2. Characteristics and applications of the wireless video transmission system

1) Stable performance with low cost

Free from the hassle of wiring, wireless video transmission is no longer restricted by wires and cables, making the preparation work easier and more efficient, and allowing the cameraman to move around on the shooting site with more flexibility and freedom. The WiFi-enabled technology guarantees multi-party real-time monitoring via the mobile APP, which greatly facilitates team collaboration and efficiency. Wireless video transmission equipment with high cost-effectiveness and good performance on the market, such as Mars 400s pro and Mars 300 pro system of Hollyland, are compatible with SDI and HDMI interface connections at the same time. An investment of less than $1,000 can meet the video transmission needs of most film crews for daily shooting.

2) Features and advantages of wireless AV transmission in film and television applications

● Real-time transmission

Both WiFi and WHDI technologies are widely used in video transmission. WHDI technology, an industry benchmark for wireless video transmission, provides a high-quality, uncompressed wireless connection. Systems that adopt the MIMO technology and OFDM modulation method can achieve a transmission rate of up to 3Gbps. Transmitting with no latency, and no compression in a carrier-grade also makes it expensive, with prices for the technology typically reaching over $2,000 on the market.

However, solutions using WiFi or other wireless signal frequency band transmission technologies are less expensive. Products using WiFi transmission technology are compatible with mobile devices for multi-party monitoring. Although the anti-interference performance is not as good as that of WHDI devices, they generally transmit with less than 0.1s latency that can meet the basic monitoring requirements of the crew's work, making them more cost-effective.

The application of different technologies brings a wide range of options to the user. In large-scale and high-investment film and TV production projects, where real-time monitoring and precise capturing is strictly required, the WHDI solution would be a more suitable choice for teams with sufficient budgets.

The better wireless video transmission products adopting WiFi or radio frequency transceiving technologies on the market can realize video and audio transmission with a delay of less than 0.08s, and some even reach a delay of less than 0.04s, which can basically meet the requirements of shooting and focus pulling. And they are widely accepted by small crews and individual creators in their daily shoots.

● High-definition video quality

Solutions using WHDI technology can reach the specifications of 4K60fps, and WiFi or other radio frequency transceiving systems can generally reach the specifications of 1080p60fps. For most production teams, resolution up to 1080p is clear enough and more cost-effective for on-site monitoring, especially if taking into account the capacity of the monitors that production teams generally use.

● Coherence

For video transmission solutions with physical wired connections, the realtimeness and steadiness in their performance is the major advantage. But we are also very excited to discover that wireless video transmission has also made breakthroughs in this area. Recently, we have noticed that Hollyland's Cosmo C1 boasting its industry-first HEVO technology pioneered the integration of automatic frequency hopping and retransmission mechanisms that achieve a smooth monitoring experience without a black screen with a latency of less than 0.04s. As technologies in the industry continue to evolve, wireless video solutions are gradually approaching or rivaling wired devices in terms of real-time and coherence.

● Integration

With the rapid development of the Internet and the continuous increase in the scale of netizens, the online live broadcast industry has continued to develop in recent years with more individual creators engaged in this video content production. Developers are constantly exploring the potentials and innovations in the endeavor of bettering the complicated and once cumbersome workflows in film productions. We have observed that some manufacturers have begun to integrate technologies such as video capture and codec into video transmission system equipment, providing more diverse and cost-effective integrated solutions for various types of shooting projects.

Compared with the traditional video capture method, the video stream of the video transmission is obtained through the video capture card, or the video stream of the image transmission system is obtained through the RTSP protocol. We have noticed that there are new video transmission technologies on the market that has the UVC protocol directly embedded in the transceiving device, namely, a direct livestreaming can be achieved by connecting the device with the computer only via a USB cable, without any external capture cards or other equipment. Its higher integration and lower cost of accessories make it more convenient and economical in practical applications.

Nowadays, the development of network technology has changed people's production and work habits in all aspects. The development of wireless technology is widely accepted and applied by more and more industries. The wireless video transmission system is an outcome of the continuous renewal and development of science and technology. Maybe many people are unfamiliar with this type of equipment, however, in fact, it has been used in all walks of life. For example, monitoring and Bluetooth are related to wireless transmission devices.