High dynamic range

About: High dynamic range is a research topic. Over the lifetime, 4280 publications have been published within this topic receiving 76293 citations. The topic is also known as: HDR.

The analog challenge of nanometer CMOS

Abstract: Nanometer CMOS technology offers the required integration density for advanced products such as home theatre equipment and personal communication devices. The system solutions inside these products demand highly integrated systems-on-silicon, blending high-density digital functions with analog interface circuits. These integrated solutions have to cope with high data-rates, and thus require high speed and high dynamic range circuits, without compromising power consumption. Novel choices on circuit and system level are required to handle the increased number of devices subject to high variability, running at higher intrinsic speeds with a constraint power supply.

AGIPD, a high dynamic range fast detector for the

Abstract: AGIPD — (Adaptive Gain Integrating Pixel Detector) is a hybrid pixel X-ray detector developed by a collaboration between Deutsches Elektronen-Synchrotron (DESY), Paul-Scherrer- Institut (PSI), University of Hamburg and the University of Bonn. The detector is designed to comply with the requirements of the European XFEL. The radiation tolerant Application Specific Integrated Circuit (ASIC) is designed with the following highlights: high dynamic range, spanning from single photon sensitivity up to 10 4 12.5keV photons, achieved by the use of the dynamic gain switching technique using 3 possible gains of the charge sensitive preamplifier. In order to store the image data, the ASIC incorporates 352 analog memory cells per pixel, allowing also to store 3 voltage levels corresponding to the selected gain. It is operated in random-access mode at 4.5MHz frame rate. The data acquisition is done during the 99.4ms between the bunch trains. The AGIPD has a pixel area of 200 200 mm 2 and a 500mm thick silicon sensor is used. The architecture

The specification and testing of a seismic-refraction system for crustal studies;

Abstract: A new seismic-refraction system built for the U. S. Geological Survey for crustal studies has been tested in the laboratory and shown to meet strict performance specifications for broad frequency response, low noise, high gain, and high dynamic range. The inherent advantages of magnetic recording, with selective filtering on playback, were demonstrated in field tests by the recovery of weak events that otherwise would be obscured by high seismic noise.

A real-time implementation of gradient domain high dynamic range compression using a local Poisson solver

Abstract: This paper presents a real-time hardware implementation of a gradient domain dynamic range compression algorithm for high dynamic range (HDR) images. This technique works by calculating the gradients of the HDR image, manipulating those gradients, and reconstructing an output low dynamic range image that corresponds to the manipulated gradients. Reconstruction involves solving the Poisson equation. We propose a Poisson solver that utilizes only local information around each pixel along with special boundary conditions, and requires a small and fixed amount of hardware for any image size, with no need to buffer the entire image. The hardware implementation is described in VHDL and synthesized for a field programmable gate array (FPGA) device. The maximum operating frequency achieved is fast enough to process high dynamic range videos with one megapixel per frame at a rate of about 100 frames per second. The hardware is tested on standard HDR images from the Debevec library. The output images produced have good visual quality.

Adaptive dualISO HDR reconstruction

Abstract: With the development of modern image sensors enabling flexible image acquisition, single shot high dynamic range (HDR) imaging is becoming increasingly popular. In this work, we capture single shot HDR images using an imaging sensor with spatially varying gain/ISO. This allows all incoming photons to be used in the imaging. Previous methods on single shot HDR capture use spatially varying neutral density (ND) filters which lead to wasting incoming light. The main technical contribution in this work is an extension of previous HDR reconstruction approaches for single shot HDR imaging based on local polynomial approximations (Kronander et al., Unified HDR reconstruction from raw CFA data, 2013; Hajisharif et al., HDR reconstruction for alternating gain (ISO) sensor readout, 2014). Using a sensor noise model, these works deploy a statistically informed filtering operation to reconstruct HDR pixel values. However, instead of using a fixed filter size, we introduce two novel algorithms for adaptive filter kernel selection. Unlike a previous work, using adaptive filter kernels (Signal Process Image Commun 29(2):203–215, 2014), our algorithms are based on analyzing the model fit and the expected statistical deviation of the estimate based on the sensor noise model. Using an iterative procedure, we can then adapt the filter kernel according to the image structure and the statistical image noise. Experimental results show that the proposed filter de-noises the noisy image carefully while well preserving the important image features such as edges and corners, outperforming previous methods. To demonstrate the robustness of our approach, we have exploited input images from raw sensor data using a commercial off-the-shelf camera. To further analyze our algorithm, we have also implemented a camera simulator to evaluate different gain patterns and noise properties of the sensor.