What is HD?

HD is 720p and 1080p. 720P is the lowest standard in high-definition image quality, and only when it reaches this standard can it be called high-definition. Its resolution is "1280×720", while 1080P is also called full HD, and its resolution reaches "1920×1080" ; 1080P is clearer than 720P, but the video file capacity is also larger.

The operating environment of this tutorial: Windows 7 system, Dell G3 computer.

High Definition (HD) refers to images or videos with a vertical resolution greater than or equal to 720. The sizes are generally 1280×720 and 1920×1080. "HD" stands for "high definition". Generally speaking, high-definition has four meanings: high-definition TV, high-definition equipment, high-definition format, high-definition movies, etc.

What is high-definition? ); 1080i (1920×1080, interlaced, field frequency 60); 1080p (1920×1080, non-interlaced, field frequency 24 or 30)

720P is the lowest standard in high-definition image quality, and also Only when this standard is reached can it be called high definition. Its resolution is 1280 × 720.

1080P, also called Full HD, is currently the highest standard in high-definition video. Its resolution reaches 1920 × 1080; therefore, 1080P is clearer than 720P, but the video file capacity is also larger.

Nowadays, generally Blu-ray discs store high-definition videos in 1080P, and 720P is rarely used. However, due to network transmission speed, the video file capacity of 720P is smaller than that of 1080P, and the transmission time is naturally shorter than that of 1080P. Therefore, in China, 720P high-definition video seems to be more popular.

The difference between 720P and 1080p

1. Different properties: 720P is a high-definition digital TV format. 1080p: is a full HD video display format.

2. Different features: 720P reaches a display format of 1280×720 resolution under progressive scanning. It is the fusion of digital film imaging technology and computer technology. 1080p: It is a display format that reaches a resolution of 1920×1080 under progressive scanning. It is the perfect integration of digital TV and computer technology.

3. The required code streams are different: 1080P (full HD) film source requires a code stream of 8M; 720P (HD) film source requires a code stream of 4M.

Expand knowledge:

Resolution, also known as resolution and resolution, can be subdivided into display resolution, image resolution, printing resolution and Scan resolution, etc. Resolution determines how fine the details of a bitmap image are. Typically, the higher the resolution of an image, the more pixels it contains, the clearer the image, and the better the quality of the print. At the same time, it will also increase the storage space occupied by the files.

The units used to describe resolution are: dpi (dots per inch), lpi (line per inch), ppi (pixels per inch) and PPD (PPPixels Per Degree, pixels per degree). But only lpi is a scale that describes optical resolution. Although dpi and ppi are also units within the resolution category, their meanings are different from lpi. Moreover, lpi and dpi cannot be converted and can only be estimated based on experience. In addition, ppi and dpi are often used interchangeably. But there are also differences in the fields they use. From a technical point of view, "pixels" only exist in the field of computer display, while "dots" only appear in the field of printing or printing.

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