Bayer Mosaic Pattern; Onsemi Sensor Artifacts With Fast Readout Mode - Teledyne m640 User Manual

Bayer Mosaic Pattern

Genie Nano Color cameras output raw Bayer image data using the mosaic pattern shown below.
Teledyne DALSA Sapera CamExpert tool interprets the raw Bayer output when the user enables the
Pre-Processing Software Bayer Decoder. CamExpert also provides an automatic white balance tool
to aid RGB gain adjustments.
Bayer Mosaic Pattern and the CamExpert processing function to decode the Genie Nano Color

OnSemi Sensor Artifacts with Fast Readout Mode

When the Nano OnSemi sensor models have Fast Readout mode active, the row blanking and row
readout occur in parallel in the sensor. This reduces the total frame readout time resulting in a
faster maximum frame rate. But as a consequence there are minor column artifacts (of very low
DN), typically of no significance and irrelevant for many imaging systems. Note that these column
artifacts will become more prominent as sensor gain is increased.
The image below shows a "dark" capture with Fast Readout Mode enabled and analog gain set to
maximum (8x). The artifacts will become visible as fixed pattern DN column variations near the left
edge of the video frame. There are darker columns followed by lighter columns as marked by the
overlay graphics. These DN variations are not random columns, but consistent between individual
OnSemi sensors operating in Fast Readout mode with high gain.
Operational Reference • 71
Nano Series GigE Vision Camera