LightWise ISG Allegro, Technical Manual

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ISG Allegro LightWise USB 3.0 Technical Manual Version 1.3.1
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9. LightWise Allegro USB 3.0 Attributes
Pixel Formats
The pixel formats describe the encoding scheme of the pixels in the camera output images. Pixel formats
describe each pixel in terms of color encoding, bit depth and formatting within the data stream.
Pixel formats conform to the GenICam Pixel Format Naming Convention (PFNC) v2.0. The full
PFNC can be found on the EMVA.org website and contains more details than provided below.
Not all features are available on all cameras.
The camera sensor Analog to Digital Converter (ADC) produces pixels at a particular bit depth, typically 10
bits. If the selected pixel format has fewer bits than the ADC output, the least significant bits are dropped. If the
selected pixel format has more bits per pixel than the ADC, the least significant bits are padded with zeros.
Mono
Mono formats include Mono8 (8 bit per pixel) and Mono10p (10 bits per pixel). Mono cameras only output
these formats. Selecting a Mono format bypasses image processing features and thus offers the highest frame
rates available.
RGB
Color sensors using a Bayer color filter array support Bayer pixel formats. The camera supports BayerLM8 and
BayerLM10p. Where L and M are one of R, G, or B and describe the ordering of pixels within the Bayer pattern
(see the PFNC document). These formats require the host software to reconstruct a full color image. The color
processing in the camera is bypassed when a Bayer format is selected offering the highest available frame rate.
YCrCb/YUV
This format consists of a brightness (luma) component, Y, and color (chroma) components Cb and Cr (also
referred to as U and V). So called YCC444 format is 24 bits per pixel. Subsampling the chroma channels allows
YCbCr data to use 16 bits per pixel for a faster transfer rate without significant visual difference. This is
referred to as YCC422.