What are the characteristics of HDTV?

Introduction to HDTV [Introduction to common 720P, 1080I, and 1080P display modes] While people were still immersed in the visual impact brought by DVD, HDTV quietly entered people's field of vision.

Although the word HDTV entered the country relatively late, its popularity is very fast. Once people come into contact with HDTV, they will soon be conquered by its near-perfect picture quality. Not only that, HDTV movies often have many

High sound quality, such as Dolby AC3, DTS, etc., can be said to bring a large theater back home.

The word HDTV often appears in television advertisements, which is what people often call high definition.

In fact, HDTV is a part of DTV (digital television). DTV provides many resolutions, and the current HDTV mainly has three display modes, namely 720p, 1080i and 1080p.

The letter p in 720p stands for the English word progressive, while the i in 1080i means interlaced, and the P in 1080p stands for non-interlaced.

These three display modes provide 60 images per second, 720p provides 60 images per second, and 1080i uses interlaced scanning, interleaving odd and even lines every second

It provides 30 pictures, so the picture in 1080i mode will feel a little flickering, and 1080P provides progressive scanning method based on 1080I display mode. Among all display modes, 1080p display effect is the most outstanding, but it imposes a heavy load on the system.

The requirements are also the highest.

In terms of display resolution, 720p provides 1280x720, which is 921,600 pixels, while 1080i has a resolution of 1920x1080, which has 2.073 million pixels.

The display formats of HDTV videos that can be downloaded from the Internet are: 720p (1280x720, non-interlaced), 1080i (1920x1080, interlaced), 1080p (1920x1080, non-interlaced), of which 720p and 1080i are the most common.

In terms of audio, HDTV movies generally have two standards, AC3 and DTS. In fact, these two audio standards are not new technologies. They have been widely used as early as the DVD era. Among them, AC3 is more widely used, and

Because DTS was launched late, it has not become "mainstream". In terms of sound quality, both have their own strengths. It is difficult to say who is better and who is worse. This may also be due to everyone's different understanding of sound.

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Dolby AC3, this technology provides multi-channel surround sound through different media: giving audiences a multi-channel surround sound experience through 35mm film in theaters; this technology can transmit and store 5 full-band sound channels, as well as a low-frequency

Effects channel (LFE), which occupies less storage space than a linear PCM encoded channel on a CD.

Dolby Digital also features: transmission of metadata through which playback parameters can be controlled.

The full name of dts is digital theater systems, inc., or dts for short. It works using CAC (coherent acoustics coding, coherent acoustic coding) method. In the cinema, dts recording adopts a special digital separation of sound and picture.

Stereo and digital sound are recorded on the disc and read by a dedicated optical drive. In addition, a time synchronization code is recorded between the copied analog sound and the picture to control the synchronization of the CD-ROM drive's sound reproduction and the picture.

The digital sound of the disc is encoded according to apt-x10, which is divided into 6 channels (5.1 channels): left, center, right, left surround, right surround and sub-low frequency. This is the same as Dolby Digital, but the digital compression ratio of DTS is

4:1, which is only 1/4 of the compression ratio of Dolby ac-3.

The lower the data compression ratio, the larger the recording space occupied, but the quality of the playback sound may be better. In addition, DTS adopts measures such as high bit rate and high sampling rate, which further advances its pursuit of original sound reproduction.

step.

HDTV movies are quite excellent in terms of image quality and sound quality. Compared with DVD, the picture quality of DVD can only be regarded as entry-level. However, you still need certain conditions to play HDTV movies as you like. If you still

If you don’t understand it very well, then you have to learn it, otherwise you may be “eliminated” by the times.

[Many encoding methods H.264 has emerged] The HDTV videos we can download from the Internet are mainly encoded in TS, WMV, XVID, DIVX, MKV, H.264, etc. They each have their own strengths and weaknesses, among which H.264

It has been popular recently due to the support of NVIDIA and Ati. Compared with other encoding methods, H.264 has many new features, which determine that H.264 has a brighter future.