JAI TM-6740GE, User Manual

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TM-6740GE Series
20 Operation
Figure 8. Example of TMC-6740GE in Default Mode.
It is important to meet the exact starting pixel at the line, and the starting line in frame. If the starting pixel
or line is shifted due to the image capture configuration, then the interpolation software can be adjusted for
the correct starting point.
3.2.5 Camera Functions
AccuPiXEL color cameras perform all functions the same way as B/W cameras. However, because of color
characteristics, the LUT (Look-up Table) is different. The LUT is a powerful tool to adjust the dynamic range,
as well as the color dynamic range. Since human color perception is non-linear, LUT selection can help
optimize color contrast by selecting the LUT value. Gamma 0.45 is logarithmic and is close to human
perception.
When LUT is selected, black-level adjustment must be more accurate than for B/W cameras.
3.2.6 Interpolation Software
The color interpolation can be performed in the frame grabber or by using the host computer’s CPU. Most
major frame grabbers with processing capability provide tools for color interpolation. Software vision packages
also provide color interpolation capability, but speed and performance may be determined by the PC’s
resources and by the complexity of the interpolation routine.
3.2.7 Color Interpolation
The Bayer pattern color filter array (CFA) consists of R, G, and B primary colors. Each pixel represents one of
three colors. In order to display or print color images, the signal has to be converted to RGB output, which has
three independent channels (outputs) and sync signals.
Color interpolation software or firmware performs the color preprocessing by
filling the missing color pixels with neighboring pixels. It then separates the
stream of data, (8-bit or 10-bit) into 3 (RGB) data (8-bit x 3) and adds the
color matrix to adjust and balance each of the R,G, and B channels (white
balance or color balance).
The image quality depends on the camera’s own pixel data (including pixel
data independency from neighboring pixels, noise and color filter), and
interpolation of the software algorithm such as 3 x 3 interpolation, 2 x 2
interpolation, color matrix, white balance capability, etc.