scispace - formally typeset
Search or ask a question
Topic

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.


Papers
More filters
Patent
16 Jun 2010
TL;DR: A processor or other device, such as a programmable and/or massively parallel processor, includes processing elements designed to perform arithmetic operations (possibly but not necessarily including, one or more of addition, multiplication, subtraction, and division) on numerical values of low precision but high dynamic range (LPHDR arithmetic) as mentioned in this paper.
Abstract: A processor or other device, such as a programmable and/or massively parallel processor or other device, includes processing elements designed to perform arithmetic operations (possibly but not necessarily including, for example, one or more of addition, multiplication, subtraction, and division) on numerical values of low precision but high dynamic range (“LPHDR arithmetic”). Such a processor or other device may, for example, be implemented on a single chip. Whether or not implemented on a single chip, the number of LPHDR arithmetic elements in the processor or other device in certain embodiments of the present invention significantly exceeds (e.g., by at least 20 more than three times) the number of arithmetic elements, if any, in the processor or other device which are designed to perform high dynamic range arithmetic of traditional precision (such as 32 bit or 64 bit floating point arithmetic).

20 citations

Journal ArticleDOI
TL;DR: A 6-bit time-to-digital converter that achieves mismatch free operation by using a single delay cell and sampling flip-flop is presented.
Abstract: A 6-bit time-to-digital converter that achieves mismatch free operation by using a single delay cell and sampling flip-flop is presented. The proposed TDC was integrated in a digital fractional-N PLL fabricated in a 32-nm digital SoC CMOS process for WiFi/WiMax radios. The TDC consumes 3 mW from a 1.05-V supply and occupies an area of 0.004 mm2. A digital frequency-locked loop is used to track and correct for PVT variations in the TDC and no additional linearization or mismatch calibrations are required. The DPLL uses a 20-bit high dynamic range DAC to drive a VCO in order to effectively realize a DCO with 100-Hz frequency resolution. The 2.5-GHz WiFi band LO output is generated from a 40-MHz reference with an integrated phase noise of - 35 dBc (10 kHz to 10 MHz) while consuming 21 mW . The worst case spur in the LO output is below - 50 dBc without requiring TDC mismatch and linearity calibration.

20 citations

Posted Content
TL;DR: The proposed algorithm includes a frame augmentation pre-processing step that deblurs and temporally interpolates frame data using events and outperforms state-of-the-art methods in both absolute intensity error and image similarity indexes.
Abstract: Event cameras are ideally suited to capture HDR visual information without blur but perform poorly on static or slowly changing scenes. Conversely, conventional image sensors measure absolute intensity of slowly changing scenes effectively but do poorly on high dynamic range or quickly changing scenes. In this paper, we present an event-based video reconstruction pipeline for High Dynamic Range (HDR) scenarios. The proposed algorithm includes a frame augmentation pre-processing step that deblurs and temporally interpolates frame data using events. The augmented frame and event data are then fused using a novel asynchronous Kalman filter under a unifying uncertainty model for both sensors. Our experimental results are evaluated on both publicly available datasets with challenging lighting conditions and fast motions and our new dataset with HDR reference. The proposed algorithm outperforms state-of-the-art methods in both absolute intensity error (48% reduction) and image similarity indexes (average 11% improvement).

20 citations

Patent
29 Apr 2010
TL;DR: In this paper, a rear modulator sub-image with color compensation techniques is generated for a front modulator without color errors arising for a certain color or color when the image display system includes pixel mosaics.
Abstract: Embodiments relate generally to computer-based image processing, and more particularly, to systems, apparatuses, integrated circuits, computer-readable media, and methods to facilitate operation of an image display system with a relatively high dynamic range by, for example, generating a rear modulator sub-image with color compensation techniques. The image display system can produce rear modulator drive levels that would enable a front modulator sub-image to be displayed without color errors arising for a certain color or colors when the image display system includes pixel mosaics.

20 citations

Journal ArticleDOI
TL;DR: A novel method for estimating the set of exposure times needed to capture the full dynamic range of a scene with high dynamic range (HDR) content, which equals or outperforms the previously developed best approach, with less shots and shorter exposure times, thereby asserting the advantage of being adaptive to scene content for exposure time estimation.
Abstract: Digital imaging of natural scenes and optical phenomena present on them (such as shadows, twilights, and crepuscular rays) can be a very challenging task because of the range spanned by the radiances impinging on the capture system. We propose a novel method for estimating the set of exposure times (bracketing set) needed to capture the full dynamic range of a scene with high dynamic range (HDR) content. The proposed method is adaptive to scene content and to any camera response and configuration, and it works on-line since the exposure times are estimated as the capturing process is ongoing. Besides, it requires no a priori information about scene content or radiance values. The resulting bracketing sets are minimal in the default method settings, but the user can set a tolerance for the maximum percentage of pixel population that is underexposed or saturated, which allows for a higher number of shots if a better signal-to-noise ratio (SNR) in the HDR scene is desired. This method is based on the use of the camera response function that is needed for building the HDR radiance map by stitching together several differently exposed low dynamic range images of the scene. The use of HDR imaging techniques converts our digital camera into a tool for measuring the relative radiance outgoing from each point of the scene, and for each color channel. This is important for accurate characterization of optical phenomena present in the atmosphere while not suffering any loss of information due to its HDR. We have compared our method with the most similar one developed so far [IEEE Trans. Image Process.17, 1864 (2008)]. Results of the experiments carried out for 30 natural scenes show that our proposed method equals or outperforms the previously developed best approach, with less shots and shorter exposure times, thereby asserting the advantage of being adaptive to scene content for exposure time estimation. As we can also tune the balance between capturing time and the SNR in our method, we have compared its SNR performance against that of Barakat's method as well as against a ground-truth HDR image of maximum SNR. Results confirm the success of the proposed method in exploiting its tunability to achieve the desired balance of total Δt and SNR.

20 citations


Network Information
Related Topics (5)
Pixel
136.5K papers, 1.5M citations
88% related
Image processing
229.9K papers, 3.5M citations
86% related
Convolutional neural network
74.7K papers, 2M citations
83% related
Feature extraction
111.8K papers, 2.1M citations
83% related
Image segmentation
79.6K papers, 1.8M citations
82% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
2023122
2022263
2021164
2020243
2019238
2018262