Abstract: A method for transcoding from an MPEG-2 format to an H.264 format is disclosed. The method generally comprises the steps of (A) decoding an input video stream in the MPEG-2 format to generate a plurality of macroblocks; (B) determining a plurality of indicators from a pair of the macroblocks, the pair of the macroblocks being vertically adjoining; and (C) coding the pair of the macroblocks into an output video stream in the H.264 format using one of (i) a field mode coding and (ii) a frame mode coding as determined from the indicators.

Abstract: Disclosed embodiments provide for a an image signal processing system that includes back-end pixel processing unit that receives pixel data after being processed by at least one of a front-end pixel processing unit and a pixel processing pipeline. In certain embodiments, the back-end processing unit receives luma/chroma image data and may be configured to apply face detection operations, local tone mapping, bright, contrast, color adjustments, as well as scaling. Further, the back-end processing unit may also include a back-end statistics unit that may collect frequency statistics. The frequency statistics may be provided to an encoder and may be used to determine quantization parameters that are to be applied to an image frame.

Abstract: Some embodiments of the invention provide a mobile device that captures and produces images with high dynamic ranges. To capture and produce a high dynamic range image, the mobile device of some embodiments includes novel image capture and processing modules. In some embodiments, the mobile device produces a high dynamic range (HDR) image by (1) having its image capture module rapidly capture a succession of images at different image exposure durations, and (2) having its image processing module composite these images to produce the HDR image.

Abstract: The present disclosure provides techniques for performing audio-video synchronization using an image signal processing system. In one embodiment, a time code register provides a current time stamp when sampled. The value of the time code register may be incremented at regular intervals based on a clock of the image signal processing system. At the start of a current frame acquired by an image sensor, the time code register is sampled, and a timestamp is stored into a timestamp register associated with the image sensor. The timestamp is then read from the time stamp register and written to a set of metadata associated with the current frame. The timestamp stored in the frame metadata may then be used to synchronize the current frame with a corresponding set of audio data.

Abstract: A method for preparing a pressed article comprises providing a first and a second pressing ram in a compression chamber; supplying biomass particles in the chamber closing the chamber; extending the first pressing ram; displacing the biomass particles with the first pressing ram towards the second pressing ram; detecting abutment of the biomass particles on the second pressing ram; applying pressure to the biomass particles with the first pressing ram and with the second pressing ram detecting a pressure applied to match a predetermined pressure and continuing to extend the first and the second pressing ram until a predetermined time at the matched compression pressure has elapsed; stopping the extension of the second pressing ram when a predetermined extension length is reached; continuing to extend the first pressing ram until a predetermined additional time has elapsed after the stopping; ejecting a pressed article.

Abstract: Systems and methods are provided for collecting image statistics using a pixel mask. In one example, statistics collection logic of an image signal processor may include a pixel weighting mask and accumulation logic. The pixel weighting mask may receive a first representation of a pixel that includes a luma and chroma representation of the pixel. The pixel weighting mask may output a pixel weighting using first and second chroma components of the luma and chroma representation of the pixel. The accumulation logic may receive the first or a second representation of the pixel and the pixel weighting value. Using these, the accumulation logic may weight the second representation of the pixel or the first representation of the pixel using the pixel weighting value to obtain a weighted pixel value, adding the weighted pixel value to a statistics count.

Abstract: Some embodiments provide a method of aligning a pair of images. The method defines multiple different pairs of images at multiple different resolutions. The method hierarchically aligns the original pair of images by first aligning the pair of images at the lowest resolution and then aligning each pair of images at each higher resolution based on the alignments of the pair of images at the lower resolutions. For some of the resolutions, to perform the hierarchically alignment, the method identifies, for at least one image at each resolution, portions that are suitable for performing the alignment and portions that are not suitable for performing the alignment. The method compares each pair of images at a particular resolution by using the suitable portions while excluding the unsuitable portions from the comparison.

Abstract: A method for transcoding from an MPEG-2 format to a VC-1 format is disclosed. The method generally comprises the steps of (A) decoding an input video stream in the MPEG-2 format to generate a picture; (B) determining a mode indicator for the picture; and (C) coding the picture into an output video stream in the VC-1 format using one of (i) a VC-1 field mode coding and (ii) a VC-1 frame mode coding as determined from the mode indicator.

Abstract: Certain aspects of this disclosure relate to an image signal processing system that includes a flash controller that is configured to activate a flash device prior to the start of a target image frame by using a sensor timing signal. In one embodiment, the flash controller receives a delayed sensor timing signal and determines a flash activation start time by using the delayed sensor timing signal to identify a time corresponding to the end of the previous frame, increasing that time by a vertical blanking time, and then subtracting a first offset to compensate for delay between the sensor timing signal and the delayed sensor timing signal. Then, the flash controller subtracts a second offset to determine the flash activation time, thus ensuring that the flash is activated prior to receiving the first pixel of the target frame.

Abstract: Various techniques are provided herein for the demosaicing of images acquired and processed by an imaging system. The imaging system includes an image signal processor and image sensors utilizing color filter arrays (CFA) for acquiring red, green, and blue color data using one pixel array. In one embodiment, the CFA may include a Bayer pattern. During image signal processing, demosaicing may be applied to interpolate missing color samples from the raw image pattern. In one embodiment, interpolation for the green color channel may include employing edge-adaptive filters with weighted gradients of horizontal and vertical filtered values. The red and blue color channels may be interpolated using color difference samples with co-located interpolated values of the green color channel. In another embodiment, interpolation of the red and blue color channels may be performed using color ratios (e.g., versus color difference data).

Abstract: Certain embodiments disclosed herein relate to an image signal processing system includes overflow control logic that detects an overflow condition when a destination unit when a sensor input queue and/or front-end processing unit receives back pressure from a downstream destination unit. In one embodiment, pixels of a current frame are dropped when an overflow condition occurs. The number of dropped pixels may be tracked using a counter. Upon recovery of the overflow condition, the remaining pixels of the frame are received and each dropped pixel may be replaced using a replacement pixel value.

Abstract: 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.

Abstract: Systems and methods may employ separate image sensors for collecting different types of data. In one embodiment, separate luma, chroma and 3-D image sensors may be used. The systems and methods may involve generating an alignment transform for the image sensors, and using the 3-D data from the 3-D image sensor to process disparity compensation. The systems and methods may involve image sensing, capture, processing, rendering and/or generating images. For example, one embodiment may provide an imaging system, including: a first image sensor configured to obtain luminance data of a scene; a second image sensor configured to obtain chrominance data of the scene; a third image sensor configured to obtain three-dimensional data of the scene; and an image processor configured to receive the luminance, chrominance and three-dimensional data and to generate a composite image corresponding to the scene from that data.

Abstract: Various techniques are disclosed for processing statistics data in an image signal processor (ISP). In one embodiment, a statistics collection engine may be configured to acquire statistics relating to auto white-balance. The statistics collection engine may receive raw Bayer RGB data acquired by an image sensor and may be configured to perform one or more color space conversions to obtain pixel data in other color spaces. A set of pixel filters may be configured to accumulate sums of the pixel data conditionally based upon YC1C2 characteristics, as defined by a pixel condition per pixel filter. Depending on a selected color space, the pixel filters may generate color sums, which may be used to match a current illuminant against a set of reference illuminants with which the image sensor has been previously calibrated.

Abstract: Systems, methods, and devices for sharpening image data are provided. One example of an image signal processing system includes a YCC processing pipeline that includes luma sharpening logic. The luma sharpening logic may sharpen the luma component while avoiding sharpening some noise. Specifically, a multi-scale unsharp mask filter may obtain unsharp signals by filtering an input luma component, and sharp component determination logic may determine sharp signals representing differences between the unsharp signals and the luma component. Sharp lookup tables may “core” the sharp signals, which may prevent some noise from being sharpened. Output logic may determine a sharpened output luma signal by combining the sharp signals with, for example, luma component or one of the unsharp signals.

Abstract: Systems and methods for generating local image statistics are provided. In one example, an image signal processing system may include a statistics pipeline with image processing logic and local image statistics collection logic. The image processing logic may receive and process pixels of raw image data. The local image statistics collection logic may generate a local histogram associated with a luminance of the pixels of a first block of pixels of the raw image data or a thumbnail in which a pixel of the thumbnail represents a downscaled version of the luminance of the pixels of the first block of the pixel. The raw image data may include many other blocks of pixels of the same size as the first block of pixels.

Abstract: Systems and methods for down-scaling are provided. In one example, a method for processing image data includes determining a plurality of output pixel locations using a position value stored by a position register, using the current position value to select a center input pixel from the image data and selecting an index value, selecting a set of input pixels adjacent to the center input pixel, selecting a set of filtering coefficients from a filter coefficient lookup table using the index value, filtering the set of source input pixels to apply a respective one of the set of filtering coefficients to each of the set of source input pixels to determine an output value for the current output pixel at the current position value, and correcting chromatic aberrations in the set of source input pixels.

Abstract: The present disclosure generally relates to systems and methods for image data processing. In certain embodiments, an image processing pipeline may compute noise statistics associated with image data by receiving a frame of the image data having a plurality of pixels. The image processing pipeline may then identify a plurality of portions of the frame of the image data such that each portion of the plurality of portions has a flat surface. The image processing pipeline may then calculate a plurality of gradients for each portion of the plurality of portions, determine one or more dominant gradient orientations for each portion of the plurality of portions, and generate a histogram that represents a plurality of dominant gradient orientations that corresponds to the plurality of portions. After generating the histogram, the image processing pipeline may store the histogram, which may represent the noise statistics, in a memory.

Abstract: Systems and methods for correcting intensity drop-offs due to geometric properties of lenses are provided. In one example, a method includes receiving an input pixel of the image data, the image data acquired using an image sensor. A color component of the input pixel is determined. A gain grid is determined by pointing to the gain grid in external memory. Each of the plurality of grid points is associated with a lens shading gain selected based upon the color of the input pixel. A nearest set of grid points that enclose the input pixel is identified. Further, a lens shading gain is determined by interpolating the lens shading gains associated with each of the set of grid points and is applied to the input pixel.

Abstract: The present disclosure generally relates to systems and methods for image data processing. In certain embodiments, an image processing pipeline may collect statistics associated with fixed pattern noise of image data by receiving a first frame of the image data comprising a plurality of pixels. The image processing pipeline may then determine a sum of a first plurality of pixel values that correspond to at least a first portion of the plurality of pixels such that each pixel in at least the first portion of the plurality of pixels is disposed along a first axis within the frame of the image data. After determining the sum of the first plurality of pixel values, the image processing pipeline may store the sum of the first plurality of pixel values in a memory such that the sum of the first plurality of pixel values represent the statistics.