229 results about "High-dynamic-range imaging" patented technology

The present invention can provide solutions to many common imaging problems, such as, for example, unevenly distributed illumination, shadows, white balance adjustment, colored ambient light and high dynamic range imaging. Imaging systems and methods can be provided through a computer (e.g., laptop or desktop) such that the system or method can take advantage of the computer's processing power to provide functionality that goes beyond typical camera. Such an imaging system may include an imaging device, a camera, a light source and a user interface.

The present invention discloses a high dynamic range imager circuit and a method for reading high dynamic range image with an adaptive conversion gain. The high dynamic range image circuit includes a variable capacitor. The capacitance of the variable capacitor is adjusted according to sensed light intensity or by internal feedback control, to adaptively adjust the conversion gain of the high dynamic range image circuit as it reads a signal which relates to a pixel image sensed by an image sensor device. In each cycle, the signal can be read twice or more with different dynamic ranges, to enhance the accuracy of the signal.

Motion/Saturation detection system and method for synthesizing high dynamic range motion blur free images from multiple captures, the system and method utilizing photocurrent estimation to reduce read noise and enhance dynamic range at the low illumination end, saturation detection to enhance dynamic range at the high illumination end, and motion blur detection to ensure the photocurrent estimation is not corrupted by motion. Motion blur detection also makes it possible to extend exposure time and to capture more images, which can be used to further enhance dynamic range at the low illumination end. The present invention operates completely locally, making it well suited for single chip digital camera implementations.

A method and apparatus for achieving high-dynamic range operation with a set of spatially distributed pixel cells is provided. A pixel array with a row of pixels having apertures of varying sizes in a metal mask formed thereon controls the sensitivity of each pixel cell to light. A neutral density filter having varying light transparency values is also provided over the set of pixel cells to control the sensitivity of each pixel cell to light. The pixel cells voltage outputted is combined to obtain high-dynamic range operation.

The present invention relates to a method capable of real-time implementable local tone mapping of high dynamic range images. In one embodiment, the present invention relates to a method capable of accomplishing real-time local tone mapping of high dynamic range images so that they have clear details without, for example, halo artifacts when viewed on standard display devices. In another embodiment, the present invention relates to a method capable of accomplishing real-time local tone mapping of high dynamic range images so that they have clear details without, for example, halo artifacts when viewed on standard display devices where such a method utilizes, in part, a modified Reinhard operator.

A method for processing high dynamic range (HDR) images by selecting preferred tone mapping operators and gamut mapping algorithms based on scene classification. Scenes are classified into indoor scenes, outdoor scenes, and scenes with people, and tone mapping operators and gamut mapping algorithms are selected on that basis. Prior to scene classification, the multiple images taken at various exposure values are fused into a low dynamic range (LDR) image using an exposure fusing algorithm, and scene classification is performed using the fused LDR image. Then, the HDR image generated from the multiple images are tone mapped into a LDR image using the selected tone mapping operator and then gamut mapped to the color space of the output device such as printer.

Embodiments of the invention provide an image processing method and a mobile terminal, and belong to the technical field of communication. The method comprises the following steps: obtaining image data of collected frames in a high dynamic range image shooting process; analyzing the brightness of the image data, determining ambient brightness, and adjusting a high dynamic exposure time based on the determined ambient brightness; shooting according to the adjusted high dynamic exposure time to generate low dynamic range image data; and calculating the low dynamic range image data according to a preset synthesis algorithm to generate a high dynamic range image. The image processing method provided by the embodiments of the invention can be used for avoiding a high dynamic range image distortion problem caused by a fixedly set high dynamic exposure time and enabling the high dynamic range image to reflect the true environments of all scenes, namely, true details of a picture can be restored.

The invention discloses a visual computing-based optical field imaging device and method. The visual computing-based optical field imaging device comprises an optical imaging system, an integrated near-infrared light source, a data transmission module, a high-capacity cache unit, a human-machine interaction device, a logic control unit and a processing unit. The invention provides an optical field imaging device based on a computing and imaging interactive mutual-beneficial mode; and with optical field imaging as the leading and deep perception and high-dynamic range imaging as the assistance, visual perception intelligent and visual cognition precision are realized, novel visual information with characteristics of large depth-of-field, wide dynamic range, actual three dimension, high resolution and capability of collecting and editing is obtained, and accuracy and robustness of a visual computing task are improved through data innovation of a visual perception source; and the optical field imaging device is widely applied to the fields of internet of things, security monitoring and control, biological recognition, intelligent transportation system, aerial remote sensing, digital medical treatment, animation media and the like.

The invention discloses an adjusting method with high dynamic range which comprises the following steps: obtaining the brightness range of images with low dynamic range according to the brightness of the images with high dynamic range, wherein the brightness range of the images with low dynamic range is the brightness range which can be displayed by a display device; and conducting linear mapping and histogram equalization on obtained results of the brightness range of the images with low dynamic range, and obtaining the images with low dynamic range. In the invention, high dynamic range adjustment technology for global mapping of single-frame images is more reasonable so as to improve the image quality, the details of bright and dark environments can be reasonably displayed simultaneously, algorithm is simple and practical, and discontinuous brightness caused by the fusion of local mapping and multi-frame images is avoided; and by providing users with the factors for controlling the image contrast and detail richness, the images are convenient for being adjusted to the effect which is more acceptable for human eyes.

Active-gated imaging system and method for imaging environment with at least one high-intensity source. A light source emits light pulses toward the environment, and an image sensor with a pixelated sensor array receives reflected pulses from a selected depth of field and generates a main image. The image sensor exposure mechanism includes a pixelated transfer gate synchronized with the emitted pulses. An image processor identifies oversaturated image portions of the main image resulting from a respective high-intensity source, and interprets the oversaturated image portions using supplementary image information acquired by image sensor. The supplementary information may be obtained from: a low-illumination secondary image having substantially fewer gating cycles than the main image; by accumulating reflected pulses from the high-intensity source after the reflected pulses undergo internal reflections between optical elements of the camera; or a low-illumination secondary image acquired by residual photon accumulation during a non-exposure state of image sensor.

Methods and apparatuses for correcting image artifacts in a high dynamic range image formed by combining a plurality of exposures taken at different integration periods. A determination is made as to whether there is motion between the exposures. If motion is detected, pixel signal values chosen are replaced with pixel signal values from another exposure.

A pixel sensor cell of improved dynamic range and a design structure including the pixel sensor cell embodied in a machine readable medium are provided. The pixel cell comprises a coupling transistor that couples a capacitor device to a photosensing region (e.g., photodiode) of the pixel cell, the photodiode being coupled to a transfer gate and one terminal of the coupling transistor. In operation, the additional capacitance is coupled to the pixel cell photodiode when the voltage on the photodiode is drawn down to the substrate potential. Thus, the added capacitance is only connected to the imager cell when the cell is nearing its charge capacity. Otherwise, the cell has a low capacitance and low leakage. In an additional embodiment, a terminal of the capacitor is coupled to a “pulsed” supply voltage signal that enables substantially full depletion of stored charge from the capacitor to the photosensing region during a read out operation of the pixel sensor cell. In various embodiments, the locations of the added capacitance and photodiode may be interchanged with respect to the coupling transistor. In addition, the added capacitor of the pixel sensor cell allows for a global shutter operation.

The invention provides an optical imaging system for temporally aligning bracketed exposures of a single image, the system comprising a light aperture, a prism and a image capturing device, where the prism is capable of splitting an incoming image from the light aperture into at least two temporally aligned images, and where the image capturing device captures the temporally aligned images at different levels of exposure.

An approach is provided for generating a high dynamic range image from a low dynamic range image. The generation is performed using a mapping relating input data in the form of input sets of image spatial positions and a combination of color coordinates of low dynamic range pixel values associated with the image spatial positions to output data in the form of high dynamic range pixel values. The mapping is generated from a reference low dynamic range image and a corresponding reference high dynamic range image. Thus, a mapping from the low dynamic range image to a high dynamic range image is generated on the basis of corresponding reference images. The approach may be used for prediction of high dynamic range images from low dynamic range images in an encoder and decoder. A residual image may be generated and used to provide improved high dynamic range image quality.

The application relates to an in-pixel high dynamic range imaging system and imaging sensor pixels. Embodiments of the invention describe providing high dynamic range imaging (HDRI or simply HDR) to an imaging pixel by coupling a floating diffusion node of the imaging pixel to a plurality of metal-oxide semiconductor (MOS) capacitance regions. It is understood that a MOS capacitance region only turns on (i.e., changes the overall capacitance of the floating diffusion node) when the voltage at the floating diffusion node (or a voltage difference between a gate node and the floating diffusion node) is greater than its threshold voltage; before the MOS capacitance region is on it does not contribute to the overall capacitance or conversion gain of the floating diffusion node. Each of the MOS capacitance regions will have different threshold voltages, thereby turning on at different illumination conditions. This increases the dynamic range of the imaging pixel, thereby providing HDR for the host imaging system.

The invention proposes a method used for generating a high dynamic range image with a single low dynamic range image. The method comprises the steps that based on the human visual characteristics, the luminance component and the chrominance component of the low dynamic range image are separated; gamma correcting and edge-preserving filtering are carried out on the luminance component; the basic layer of the luminance component is extracted; traverse operating is carried out on the basic layer and the luminance component to acquire the detail layer of the luminance component; an anti-tone mapping function is constructed; anti-tone mapping operation is carried out on the detail layer and the gamma-corrected luminance image to acquire the respective anti-color collimated image; the luminance component after anti-tone mapping and the detail layer are merged to acquire a new luminance component; the chrominance component and the new luminance component are merged; and contrast stretching and denoising are carried out on the merged image to acquire the final high dynamic range image. According to the invention, the high dynamic range image is acquired through the single low dynamic range image, and the method has the advantages of good processing effect, high operability and wide applicability.

A new high dynamic range image synthesis which can handle the local object motion, wherein an interactive graphical user interface is provided for the end user, through which one can specify the source image for separate part of the final high dynamic range image, either by creating a image mask or scribble on the image. The high dynamic range image synthesis includes the following steps: capturing low dynamic range images with different exposures; registering the low dynamic range images; estimating camera response function; converting the low dynamic range images to temporary radiance images using estimated camera response function; and fusing the temporary radiance images into a single high dynamic range (HDR) image by employing a method of layered masking.