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9.1.2 Pixel Format
On Baumer digital cameras the pixel format depends on the selected image format.
Definitions 9.1.2.1
RAW: Raw data format. Here the data are stored without processing.
Bayer: Raw data format of color sensors.
Color filters are placed on these sensors in a checkerboard pattern, generally
in a 50% green, 25% red and 25% blue array.
Mono: Monochrome. The color range of mono images consists of shades of a single
color. In general, shades of gray or black-and-white are synonyms for mono-
chrome.
RGB: Color model, in which all detectable colors are defined by three coordinates,
Red, Green and Blue.
Red
Green
Blue
Black
White
The three coordinates are displayed within the buffer in the order R, G, B.
BGR: Here the color alignment mirrors RGB.
YUV: Color model, which is used in the PAL TV standard and in image compression.
In YUV, a high bandwidth luminance signal (Y: luma information) is transmitted
together with two color difference signals with low bandwidth (U and V: chroma
information). Thereby U represents the difference between blue and luminance
(U = B - Y), V is the difference between red and luminance (V = R - Y). The third
color, green, does not need to be transmitted, its value can be calculated from
the other three values.
YUV 4:4:4
Here each of the three components has the same sample rate.
Therefore there is no subsampling here.
YUV 4:2:2 The chroma components are sampled at half the sample rate.
This reduces the necessary bandwidth to two-thirds (in relation to
4:4:4) and causes no, or low visual differences.
YUV 4:1:1 Here the chroma components are sampled at a quarter of the
sample rate.This decreases the necessary bandwith by half (in
relation to 4:4:4).
◄ Figure 9
Sensor with Bayer
Pattern
◄ Figure 10
RBG color space dis-
played as color tube.