This paper considers the problem of high-dynamic-range (HDR) image capture using low-dynamic-range (LDR) cameras. We present three different minimal-bracketing algorithms for computing minimum-sized exposure sets bracketing of HDR scenes. Each algorithm is applicable to a different HDR-imaging scenario depending on the amount of target-scene-irradiance information and real-time image processing available at the time of image acquisition. We prove the optimality of each algorithm with respect to its ability to obtain a theoretically minimum-size bracketing set of exposures. We also provide closed-form expressions for computing minimal-bracketing exposure sets for two common types of HDR-imaging systems, those with geometrically varying and arithmetically varying exposure settings. We experimentally demonstrate the advantages of the proposed methods by capturing and processing multiple HDR scenes using minimal-bracketing and 1-stop bracketing methods. The results show that minimal-bracketing can be used to produce high-quality HDR images, while requiring only one third as many LDR images be acquired compared to 1-stop bracketing. We also perform a detailed SNR analysis that quantifies the tradeoff between signal-to-noise ratio and image-bracketing-set size.

Absfract-In this paper we introduce a new signalling architecture called Dual-header Optical Burst Switching (DOBS) for next generation burst-switching optical networks. Using DOBS, the functional offset size of eveq burst on a given link can he set to the same size without the use of fiber delay Line buffers.This al1ows DOBS to realize lower burst-scheduling complehity, lower ingress delay, higher throughput and better fairness than conventional single-header OBS systems. We present a new burst5cheduling algorithm called FreeChannel Queue scheduling that requires only O(1) time to execute and that achieves optimal performance in constant-offset DOBS systems. Using simulation, we find that the blocking probability of a 16-channel DOBS system is 50% lower than that of a similar LAW-VF JET OBS system. We also show that DOBS achieves better fairness than JET OBS with respect to burst length and with respect to the residual path length of bursts.

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In this paper, we present a method of using digital micro-mirror devices to dynamic range enhancement of a digital optical microscope images. Our adaptive feedback illumination control generates a high dynamic range image through an algorithm that combines the DMD-to-camera pixel geometrical mapping and a feedback operation. The feedback process automatically generates an illumination pattern in an iterative fashion that spatially modulates the DMD array elements on pixel-by-pixel level. Via experiment, we demonstrate a system that uses precise DMD control of the projector to enhance the dynamic range ideally by a factor of 573. Results are presented showing approximately 5 times the camera dynamic range, enabling visualization over a wide range of specimen characteristics.