BT.2020 is also called s Rec. 2020. It is a set of specifications covering various aspects of video broadcasting.
On August 23, 2012, the International Telecommunications Union (ITU) released its first version of Rec. 2020, defining various aspects of ultra-high-definition television (UHDTV) with standard dynamic range (SDR) and wide color gamut (WCG).
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BT.2020 has clear regulations and requirements in terms of picture resolutions, frame rates, bit depths, digital representation, system colorimetry, transfer characteristics, RGB and luma-chroma color representations, and color arrangement.
Resolution (Square Pixels Only) | 4K: 3840×2160 8K: 7680×4320 |
Frame Rate (Progressive Scan Only) | 120p, 119.88p, 100p, 60p, 59.94p, 50p, 30p, 29.97p, 25p, 24p, or 23.976p |
Bit Depth | 10 or 12 bits per sample |
In terms of resolution, BT.2020 defines that 4K should be 3840×2160 and 8K should be 7680×4320. The aspect ratio should be 16:9 and only use square pixels.
System colorimetry requirements are as follows.
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To conclude, BT.2020 (Rec. 2020) is a set of specifications defined by ITU to regulate Ultra HD broadcasting industry.