Merging VCube, Руководство пользователя

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Appendices : Video Formats and Bandwidth Page 236
4.2.0
4.2.0 Is the color sampling mode used in DV PAL. It's also used for HD video broadcast. There are 6 values for 4 pix-
els leading to 1.5 for computation purposes.
4.1.1
4.1.1 Is the color sampling mode used in DV NTSC. There are 6 values for 4 pixels leading to 1.5 for computation
purposes.
Color Space
Color space as a color model is an abstract mathematical model describing the way colors can be represented as
numbers, typically as three or four values or color components (e.g. RGB and CMYK are color models). However, a
color model with no associated mapping function to a reference color space is a more or less arbitrary color sys-
tem with little connection to the requirements of any given application.
RGB uses additive color mixing, because it describes what kind of light needs to be emitted to produce a given
color. Light is added together to create form from out of the darkness. RGB stores individual values for red, green
and blue. RGBA is RGB with an additional channel, alpha, to indicate transparency.
YPbPr (also referred to as "YPrPb", "PrPbY", and "PbPrY") is a color space used in video electronics. It is numerically
equivalent to the YCbCr colour space, but is designed for use in analogue systems whereas YCbCr is intended for
digital video.
YCbCr is a family of color spaces used in video systems. Y is the luma component and Cb and Cr the chroma com-
ponents. It is often confused with the YUV colour space and typically the terms YCbCr and YUV are used inter-
changeably, leading to confusion. In fact, when referring to signals in digital form, the term "YUV" probably really
means "YCbCr" more often than not.
Bit Depth
As usual in digital conversion of values, the higher the bit depth, the higher the resolution.
As usual, more bits means more information, higher bandwidth, higher technical requirements.
• -8 bit leads to 256 possible values
• 10 bit leads to 1024 possible values