It was first born in Germany. In the early 1990s, Germany ITT Company launched the world's first digital color TV set, which was a great shock, but this digital color TV set did not have much advantage because of its high cost. The reason of high cost is that it uses frame memory. At that time, the production technology of integrated circuits was still very backward compared with today, and the circuit density was very low, so the cost was very high. Although the function of this digital color TV is simple, it has reached a very high level in technology, such as Y/C separation and field flicker processing with digital filtering technology. ITT Company only produced about 3,000 such TV sets, and never produced them again. At that time, people couldn't imagine that TV technology could develop so fast today, and it suddenly changed from analog signal to digital signal, so people called it the first digital TV set in the world.

On this basis, people later invented picture-in-picture TV, and then invented plug-in TV, or high-definition TV (IDTV), which is now double-line and double-field TV and so on. These TVs only do some simple digital processing on video signals, and the picture quality has not been significantly improved. But people thought it was a great digital TV technology at that time. Our country also defined this kind of TV as digital TV, and formulated the digital TV standard, which was used until 2000. Therefore, many domestic TV manufacturers describe their plug-in TV sets as digital TV sets.

In fact, at that time, foreign all-digital signal TV sets were born, and digital signal broadcasting began in the 1990s, such as early MAC, MUSE, and later DVB-S, DVB-C, DVB-T, HDTV and so on. Because the new standard of domestic digital TV has not been determined for a long time, and the old standard is not outdated, various domestic digital TV concepts are flying all over the sky, such as digital TV of some companies.

The development of digital TV is gradual. If traced back to the source, it should be traced back to Mr. Fourier more than 60 years ago. His Fourier transform theory laid the foundation of digital TV technology. After him, there are a lot of applied scientists who have worked quietly for more than 50 years. The birth of MPEG source coding technology standard indicates that digital TV technology has basically matured. Two important patented technologies of 17 in MPEG source coding technology occurred in 1950, namely Huffmancoging and differential pulse code modulation (DPCM). The following 15 important technologies are basically distributed on the time axis according to uniform density, so it can be seen that hard work cannot be invented by someone with inspiration. The application of these technologies is for one purpose, that is, to enable digital signals to be transmitted in various lines.

The technical basis of digital TV is analog-to-digital converter (ADC) and coding technology. Coding technology has now become a very popular science and technology. It is a new application technology, which combines mathematics, physics and other sciences. In all-digital TV technology, there are two key coding technologies-source coding and channel coding. The main task of source coding is to solve the problem of image signal compression and preservation; The main task of channel coding is to solve the problem of image signal transmission.