摘要:
A method of generating a 2-D extended image from a video sequence representing a natural 3-D scene first determines motion parameters for a camera that recorded the scene with respect to a bakcground object from the video sequence using a structure-from-motion algorithm. The motion parameters include a rotation matrix, a translation vector and a depth map representing the depth of each point in the background object from the camera. Next from the motion parameters and depth map the 2-D extended image is generated for the background object as a composition of the images from the video sequence using a plane perspective projection technique. The background object may be layered as a function of depth and flatness criteria to form a set of layered 2-D extended images for the background object from the video sequence.
摘要:
A histogram-based segmentation of images in a video signal via color moments is initialized by a user defining regions in objects of interest from one or more images, key frames or pictures of the video signal. For each rectangle a normalized average color moment and associated co-variance matrix are determined which define a color class for that rectangle. From the normalized average color moment and associated co-variance garbage parameters are generated. Segmentation is then performed on a block basis on each image of the video sequence, a normalized color moment being generated for each block. Using a log likelihood test the closest color class for the block is determined. Based upon the closest color class and the garbage parameters for that color class a final determination is made in a two stage test as to whether the block belongs to the closest class or to a “garbage” class. All the continguous blocks that belong to a specific color class form the segmented object, and all of the objects are segmented in this manner.
摘要:
A bit rate control mechanism for a digital image or video compression system estimates a complexity parameter for a current picture, or block of samples, of a video signal as a function of parameters for a prior picture of the video signal, which parameters include a bit rate. From the complexity parameter a quality factor for the current picture is determined and applied to a quantizer to compress the current picture. A complexity pre-processor may also be used to detect scene changes in the video signal prior to estimating the complexity parameter. If there is a scene change detected, then the rate control mechanism is reset prior to estimating the complexity parameter for the first picture in the new scene.
摘要:
Implementations generally relate to data-charge phase data compression. In one implementation, a method includes computing prediction values for image data, where the image data is data-charge phase data, and where the computing of prediction values is based on inter-block prediction. The method also includes computing residual data based on the prediction values. The method also includes quantizing the residual data. The method also includes entropy encoding the quantized residual data. The method also includes refining an inverse quantized residual data based on one or more of the residual data and a number of left-over bit-budget after entropy encoding.
摘要:
Implementations generally relate to pre-charge phase data compression. In some implementations, a method includes computing prediction values for image data, where the image data is pre-charge phase data. The method also includes computing residual data based on the prediction values. The method also includes quantizing the residual data. The method also includes entropy encoding the quantized residual data. The method also includes refining an inverse quantized residual data based on one or more of the residual data and a number of left-over bit-budget after entropy encoding.
摘要:
A method and apparatus for adaptive interpolation filtering for image compression is disclosed. The method includes determining an activity measure associated with a set of pixels neighboring a pixel undergoing intraframe prediction or a distance measure between at least one pixel in the set of pixels and the pixel undergoing intraframe prediction, and selecting a filter for filtering at least a portion of the set of pixels in accordance with the at least one of the activity measure or the distance measure.
摘要:
An apparatus and method for encoding video using directional discrete waveform transforms (DDWT), such as within a codec device. DDWT can be utilized to replace the use of intra transforms and inter transforms within the encoding system. In many ways the output of the DDWT can be compared with that provided using MDDT, however, it does not require a training process while it also provides enhanced encoding of feature edges with desirable visual characteristics. The transforms are applied in at least two passes, along the prediction direction, and then across the prediction direction, instead of being applied in fixed vertical and horizontal directions. Directional scaling is not required prior to the second stage of transforms.
摘要:
A system for implementing and utilizing a lens array in an electronic device includes a sensor array coupled to the electronic device for capturing image data corresponding to a photographic target. The lens array includes a plurality of lenses that each has a different respective principal focal length to transmit reflected light from the photographic target to the sensor array. The sensor array captures a set of MFP images that each corresponds with a respective one of the lenses in the MFP lens array. The electronic device may further include an image processor that performs one or more digital signal processing procedures on the captured MFP images to thereby generate a rendered final image.
摘要:
Apparatus and methods for coding images geometric vector quantization (GVQ) having an over-complete dictionary which produces a sparse vector of coefficients as it contains large runs of zeros. The sparse encoding is particularly well suited for use with run-length entropy coding techniques. Image blocks are sparse coded using GVQ, with the vector of coefficients converted to RUN-LENGTH symbols, and binarized into a set of binary symbols. At least a portion of the binary symbols are used as contexts which can be selected when performing binary arithmetic coding of the binary coded RUN and LENGTH data to generate a bit stream containing the encoded image that provides enhanced compression.
摘要:
A method of operation of a video system includes: generating a quantization matrix for a video input data, the quantization matrix having a corner seed and a right-bottom sub-quad coefficient estimated based on the corner seed; generating a video bitstream based on the quantization matrix; and generating a reconstructed video data with the video bitstream for displaying on a video device.