High dynamic range photography without a tripod: A linear formulation for image fusion

Purpose – The purpose of this paper is to present a new multi-image registration methodology that is able to align a set of hand-held bracketed shots. Design/methodology/approach – The procedure is a two-step algorithm where corresponding multi-image points are automatically extracted from the bracketed image sequence and a least squares adjustment recovers transformation parameters. Findings – The images can be processed with high dynamic range algorithms to combine multiple low dynamic range pictures into a single mosaic with a superior radiometric quality. Originality/value – Simulated and real examples are illustrated to prove the effectiveness of the developed affine-based procedure

AUTOMATIC REGISTRATION OF MULTI-SOURCE MEDIUM RESOLUTION SATELLITE DATA

Multi-temporal and multi-source images gathered from satellite platforms are nowadays a fundamental source of information in several domains. One of the main challenges in the fusion of different data sets consists in the registration issue, i.e., the integration into the same framework of images collected with different spatial resolution and acquisition geometry. This paper presents a novel methodology to accomplish this task on the basis of a method that stands out from existing approaches. The whole data (time series) set is simultaneously co-registered with a two-dimensional multiple Least Squares adjustment with different geometric transformations implemented. Some tests were carried out with different geometric transformation models (including similarity, affine, and polynomial) and variable matching thresholds. They showed a sub-pixel precision after the computation of multiple adjustment. The use of multi-image corresponding points allowed the improvement of the registration accuracy and reliability of a time series made up of data imaged with different sensors

A Preliminary Study on Non Contact Thermal Monitoring of Microwave Photonic Systems

Microwave photonic systems are more susceptible to thermal fluctuations due tothermo-optic effect. In order to stabilize the performance of photonic components, thermal monitoringis achieved by using thermistors placed at any arbitrary location along the component. This workpresents non contact thermography of a fully functional microwave photonic system. The temperatureprofile of printed circuit board (PCB) and photonic integrated circuit (PIC) is obtained using FlukeFLIR (A65) camera. We performed Otsu’s thresholding to segment heat centers located across PCB aswell as PIC. The infrared and visible cameras used in this work have different field of view, therefore,after applying morphological methods, we performed image registration to synchronize both visibleand thermal images. We demonstrate this method on the circuit board with active electrical/photonicelements and were able to observe thermal profile of these components