Summary: | 碩士 === 國立交通大學 === 電信研究所 === 81 === This paper presents a new adaptive color correction process for
High Definition Television (HDTV) system based on human
perception model. To achieve the high-fidelity color , it
requires eliminating the color error sources resulted camera,
monitor, intermediate color image processing and mutual
interaction. The intermediate processing may include coding/
decoding, quantization, and modulation/demodulation. the mutual
interaction denotes the color gamut mismatch and resolution
conversion between camera and monitor. It can be that those
color error sources of unknown form are highly nonlinear.
Hence, a cost-effective adaptive control scheme consisting of
both back-propagation neural net controller forward model is
proposed to overcome the difficulty of with both nonlinearity
and model-identification of the HDTV systems. The forward model
is used to convert the plant error (color difference) into
control signal error for the back-propagation controller.
Furthermore, the values of derivative-related parameters of the
forward model are by Hornik's multi-layer neural net
identification process. In addition, it is noted that the
measure of the color (plant output error) should be quantified
by uniform color in order to perform the system control.
Finally, the effectiveness of our method is being verified by a
number of experiments.
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