摘要:
A pedestal level for an image sensor can be dynamically adjusted based on one or more parameters. The parameters include one or more operating conditions associated with the image sensor, pre-determined image sensor characterization data, the number of unused digital codes, and/or the number of clipped pixel signals. The operating conditions can include the temperature of the image sensor, the gain of at least one amplifier included in processing circuitry operably connected to at least one pixel, and/or the length of the integration period for at least one pixel in the image sensor. Based on the one or more of the parameters, the pedestal level is adjusted to reduce a number of unused digital codes in a distribution of dark current. Additionally or alternatively, the variance of the pixel signals can be reduced to permit the use of a lower pedestal level.
摘要:
Camera modules that may be dynamically adjusted during capture of an image. The camera may include a sensor that captures images using line scan imaging or other scanning technologies. A controller may dynamically control adjustment or movement of the camera lens by an actuator as an image is scanned by the sensor. The lens may be controlled to be in different positions and in different orientations in relation to the sensor as different lines or areas of pixels of the sensor are read. When capturing an image, a region of the sensor may be read, the lens may be adjusted, and a next region of the sensor may be read according to a pattern. Different focus, depth of field, perspective, and other effects may be achieved at different areas or regions of the image during image capture.
摘要:
Embodiments relate to color correction circuit operations performed by an image signal processor. The color correction circuit computes optimal color correction matrix on a per-pixel basis and adjusts it based on relative noise standard deviations of the color channels to steer the matrix.
摘要:
Systems and methods for local tone mapping are provided. In one example, an electronic device includes an electronic display, an imaging device, and an image signal processor. The electronic display may display images of a first bit depth, and the imaging device may include an image sensor that obtains image data of a higher bit depth than the first bit depth. The image signal processor may process the image data, and may include local tone mapping logic that may apply a spatially varying local tone curve to a pixel of the image data to preserve local contrast when displayed on the display. The local tone mapping logic may smooth the local tone curve applied to the intensity difference between the pixel and another nearby pixel exceeds a threshold.
摘要:
An image signal processor may include a pixel defect correction component that tracks defect history for frames captured by an image sensor and applies the history when identifying and correcting defective pixels in a frame. The component maintains a defect pixel location table that includes a defect confidence value for pixels of the image sensor. The component identifies defective pixels in a frame, for example by comparing each pixel's value to the values of its neighbor pixels. If a pixel is detected as defective, its defect confidence value may be incremented. Otherwise, the value may be decremented. If a pixel's defect confidence value is over a defect confidence threshold, the pixel is considered defective and thus may be corrected. If a pixel's defect confidence value is under the threshold, the pixel is considered not defective and thus may not be corrected even if the pixel was detected as defective.
摘要:
An image processing pipeline may dynamically determine filtering strengths for noise filtering of image data. Statistics may be collected for an image at an image processing pipeline. The statistics may be accessed and evaluated to generate a filter strength model that maps respective filtering strengths to different portions of the image. A noise filter may determine a filtering strength for image data received at the noise filter according to the filter strength model. The noise filter may then apply a filtering technique according to the determined filtering strength.
摘要:
Image tone adjustment using local tone curve computation may be utilized to adjust luminance ranges for images. Image tone adjustment using local tone curve computation may reduce the overall contrast of an image, while maintaining local contrast in smaller areas, such as in images capturing brightly lit scenes where the difference in intensity between brightest and darkest areas is large. A desired brightness representation of the image may be generated including target luminance values for corresponding blocks of the image. For each block, one or more tone adjustment values may be computed, that when jointly applied to the respective histograms for the block and neighboring blocks results in the luminance values that match corresponding target values. The tone adjustment values may be determined by solving an under-constrained optimization problem such that optimization constraints are minimized. The image may then be adjusted according to the computed tone adjustment values.
摘要:
An input rescale module that performs cross-color correlated downscaling of sensor data in the horizontal and vertical dimensions. The module may perform a first-pass demosaic of sensor data, apply horizontal and vertical scalers to resample and downsize the data in the horizontal and vertical dimensions, and then remosaic the data to provide horizontally and vertically downscaled sensor data as output for additional image processing. The module may, for example, act as a front end scaler for an image signal processor (ISP). The demosaic performed by the module may be a relatively simple demosaic, for example a demosaic function that works on 3×3 blocks of pixels. The front end of module may receive and process sensor data at two pixels per clock (ppc); the horizontal filter component reduces the sensor data down to one ppc for downstream components of the input rescale module and for the ISP pipeline.
摘要:
Systems and methods are provided for selectively performing image statistics processing based at least partly on whether a pixel has been clipped. In one example, an image signal processor may include statistics collection logic. The statistics collection logic may include statistics image processing logic and a statistics core. The statistics image processing logic may perform initial image processing on image pixels, at least occasionally causing some of the image pixels to become clipped. The statistics core may obtain image statistics from the image pixels. The statistics core may obtain at least one of the image statistics using only pixels that have not been clipped and excluding pixels that have been clipped.
摘要:
The present disclosure generally relates to systems and methods for image data processing. In certain embodiments, an image processing pipeline may be configured to receive a frame of the image data having a plurality of pixels acquired using a digital image sensor. The image processing pipeline may then be configured to determine a first plurality of correction factors that may correct each pixel in the plurality of pixels for fixed pattern noise. The first plurality of correction factors may be determined based at least in part on fixed pattern noise statistics that correspond to the frame of the image data. After determining the first plurality of correction factors, the image processing pipeline may be configured to configured to apply the first plurality of correction factors to the plurality of pixels, thereby reducing the fixed pattern noise present in the plurality of pixels.