Ataletsel Ölçüm Birimi Destekli Kızılötesi Görüntüleme Sistemi Tasarımı
Özet
Infrared (IR) imaging systems are frequently used in civil and military imaging
applications. Infrared image sensors are used in the focal plane array to detect
electromagnetic emissions in the wavelengths of the infrared region of the
electromagnetic spectrum. Infrared radiation, which is focused through various
optical elements and fallen onto the focal plane array, is absorbed by the infrared
sensor during a certain exposure time, and is then read as an analog electrical signal
by using the readout circuits. One of the conditions required for the IR image to not
be blurred is that the relative motion between the imaged object and IR imaging
system must be zero or remain within an acceptable limit, during the integration
time. The motion of the imaged object or the IR imaging system during the
integration time will cause blurring of the IR image. Within the scope of this thesis,
the blur caused by the IR imaging system movement has been examined and
modeled. In order to quantify the blur, an inertial measurement unit is used to
measure the movement of the IR imaging system. Thus the software for calculating
PSF for each pixel was developed using the IMU data of the movement of IR
imaging system during the integration time. After calculating the blur due to the IR
imaging system movement, the resulting blur is tried to be eliminated by using image processing techniques. In order to eliminate the blur, image processing techniques
used in the literature were examined and simulations were made about their
performance. In order to get the applicability of the obtained deblurring algorithms
on FPGA in real time, the necessary hardware and software resource were tried to
be determined. Deblurring algorithm was implemented in the Xilinx System
Generator environment using FPGA IP cores for real-time working on FPGA. In case
of use of SDRAM as a memory in real-time image deblurring, the problems that will
arise due to matrix transposition to be used in 2D-FFT application are examined.
Using this memory, it was found that image transpose would be long enough to slow
down the entire real-time image processing flow. The Corner Turn Matrix method is
designed in the System Generator environment for faster transpose of the image
and more efficient use of SDRAM memory. Deblurring algorithm designed in System
Generator environment is simulated and the results are compared with MATLAB
results. Some critical sub-IP cores of the deblurring algorithm have been tested in
real time using the development board that carries the Xilinx Zynq SoC (Sytem-onchip).
MATLAB simulations were performed for other deblurring algorithms which
were not applied in real time. As a result of the thesis study, the blur caused by the
movement of the IR imaging system in a scenario during the integration time can be
calculated quantitatively. Then this blur can be eliminated by using the deblurring
algorithm designed in the System Generator environment if it meets certain
requirements. For some types of blur, the performance of the System Generator
application may remain low. For these types of blur, images can be clarified by using
the algorithm based on the iterative least squares method designed in MATLAB.