xiMU - Technical Manual Version 2.10
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The measurement is performed on the central rectangle of the image, with 1/8
th
of its width and height. The function expects a
white sheet of paper exposed to 50% of the intensity values (8 Bit RGB values should be around 128) to be visible.
4.6.2.2.
Auto White Balance
The white balance is measured across the full image for every 4
th
image that is acquired and the white balance coefficients are
set to achieve a neutral color tint.
4.6.3.
Gamma
Only for color models: As a part of the color filtering process, it is possible to adjust the gamma level of the image. The
adjustment can be set separately for the luminosity and the chromaticity.
4.6.4.
Sharpness
Only for color models: As a part of the color filtering process, it is possible to adjust the sharpness of the image.
4.6.5.
Color Correction Matrix
The color correction matrix is a 4x4-matrix which is applied on each pixel of an image in a host-assisted port-processing step.
This Matrix can be used for example to adjust the brightness, contrast, and saturation.
4.6.6.
Bad pixel Correction
During manufacturing, every camera is going through a testing procedure where hot pixels are measured based on dark field
images. The measured hot pixels are stored inside the camera and are used for the correction of the acquired images during
operation. The correction is active by default but can be turned off by the user if a non-processed output is required.
4.7.
MU9 USB2.0 Transfer Modes
4.7.1.
Transfer mode
MU9 cameras are connected to PC with USB 2.0. BULK data transfer is used. It guaranties data delivery, but it doesn't guarantee
constant bandwidth.
4.7.2.
Packet Size Setting
Only for Windows operating systems.
The MU9 cameras have two transfer packet sizes:
•
Compatible-Size - packets with 512 bytes are used (default)
•
Enhanced-Size - packets with 1024 bytes are used
With Compatible-Size packets the camera will work correctly on more USB controllers. With Enhanced-Size packet setting - the
camera can deliver an approx. 25% higher frame-rate and lower CPU usage.
Note - not all controllers and operating systems support Enhanced-Size packets. Please test your configuration first for stability
issues.
Note -Since API V3_17_05, the communication settings were changed on MU9 cameras to Compatible-Size with 512 bytes per
packet mode as default.
To change the camera to Enhanced-Size - where packets with 1024 bytes are used use the registry settings below:
[HKEY_CURRENT_USER\SOFTWARE\SoftHard\mm40api]
"usb20pktsize"=dword:00000001
To change the camera to Compatible-Size - where packets with 512 bytes are used (default) use the registry settings below:
[HKEY_CURRENT_USER\SOFTWARE\SoftHard\mm40api]
