Patent application number | Description | Published |
20120229665 | IMAGE PROCESSING - Image processing apparatus comprises a demosaic processor for receiving a video signal comprising pixel data from an array of photosensors each having a respective color filter so as to restrict the sensitivity of that photosensor to a primary color range selected from a set of three or more primary color ranges, the array being such that the photosensors in alternate rows are sensitive to a first primary color range, and photosensors in intervening rows are sensitive to the other primary color ranges. The pixel data including pixel data from a first subset of the rows sensitive to the first primary color range, the first subset being the same from image to image of the video signal; and pixel data from a second subset of the rows of photosensors sensitive to the other primary color ranges, the second subset changing from image to image of the video signal. | 09-13-2012 |
20130121423 | VIDEO DATA ENCODING AND DECODING - Video data encoding apparatus in which arrays of video data are reordered for entropy encoding includes a frequency domain converter for generating a frequency domain representation of data derived from an input video signal, the frequency domain representation including an array of plural frequency domain coefficients in respect of each image area. The apparatus includes a selector for selecting a reordering pattern from a set of two or more candidate reordering patterns, for use in reordering the array of frequency domain coefficients. The apparatus includes a data scanner for changing the order of the frequency domain coefficients according to the selected reordering pattern so as to generate reordered coefficients. The apparatus further includes an entropy encoder for entropy-encoding the reordered coefficients. | 05-16-2013 |
20130128958 | VIDEO DATA ENCODING AND DECODING - A video data encoding apparatus in which arrays of frequency domain video data are reordered for encoding by an encoder. The apparatus includes a last data item detector for searching a current array for a last non-zero array element according to a searching pattern which searches array elements in one or more sets of a constant horizontal spatial frequency or a constant vertical spatial frequency respectively followed by any remaining array elements of the array ordered according to successive subsets, each subset being selected so that the sum of a horizontal spatial frequency component and a vertical spatial frequency component is generally constant for array elements within a subset. The apparatus including a data scanner for changing the order of the array elements for entropy encoding according to a reordering pattern so as to generate reordered array elements comprising successive subsets. | 05-23-2013 |
20150043641 | DATA ENCODING AND DECODING - A video coding or decoding method using inter-image prediction to encode input video data in which each chrominance component has 1/Mth of the horizontal resolution of the luminance component and 1/Nth of the vertical resolution of the luminance component, where M and N are integers equal to 1 or more, comprises: storing one or more images preceding a current image; interpolating a higher resolution version of prediction units of the stored images so that the luminance component of an interpolated prediction unit has a horizontal resolution P times that of the corresponding portion of the stored image and a vertical resolution Q times that of the corresponding portion of the stored image, where P and Q are integers greater than 1; detecting inter-image motion between a current image and the one or more interpolated stored images so as to generate motion vectors between a prediction unit of the current image and areas of the one or more preceding images; and generating a motion compensated prediction of the prediction unit of the current image with respect to an area of an interpolated stored image pointed to by a respective motion vector; in which the interpolating step comprises: applying a ×R horizontal and ×S vertical interpolation filter to the chrominance components of a stored image to generate an interpolated chrominance prediction unit, where R is equal to (U×M×P) and S is equal to (V×N×Q), U and V being integers equal to 1 or more; and subsampling the interpolated chrominance prediction unit, such that its horizontal resolution is divided by a factor of U and its vertical resolution is divided by a factor of V, thereby resulting in a block of MP×NQ samples. | 02-12-2015 |
20150063457 | DATA ENCODING AND DECODING - A video coding or decoding method using inter-image prediction to encode input video data in which each chrominance component has 1/Mth of the horizontal resolution of the luminance component and 1/Nth of the vertical resolution of the luminance component, where M and N are integers equal to 1 or more, comprises: storing one or more images preceding a current image; interpolating a higher resolution version of prediction units of the stored images so that the luminance component of an interpolated prediction unit has a horizontal resolution P times that of the corresponding portion of the stored image and a vertical resolution Q times that of the corresponding portion of the stored image, where P and Q are integers greater than 1; detecting inter-image motion between a current image and the one or more interpolated stored images so as to generate motion vectors between a prediction unit of the current image and areas of the one or more preceding images; and generating a motion compensated prediction of the prediction unit of the current image with respect to an area of an interpolated stored image pointed to by a respective motion vector; in which the interpolating step comprises: applying a xR horizontal and xS vertical interpolation filter to the chrominance components of a stored image to generate an interpolated chrominance prediction unit, where R is equal to (U×M×P) and S is equal to (V×N×Q), U and V being integers equal to 1 or more; and subsampling the interpolated chrominance prediction unit, such that its horizontal resolution is divided by a factor of U and its vertical resolution is divided by a factor of V, thereby resulting in a block of MP×NQ samples. | 03-05-2015 |
20150078447 | INTRA PREDICTION MODE DERIVATION FOR CHROMINANCE VALUES - A video coding or decoding method in which luminance and chrominance samples are predicted from other respective reference samples according to a prediction direction associated with a current sample to be predicted, the chrominance samples having a lower horizontal and/or vertical sampling rate than the luminance samples so that the ratio of luminance horizontal resolution to chrominance horizontal resolution is different than the ratio of luminance vertical resolution to chrominance vertical resolution, so that a block of luminance samples has a different aspect ratio to a corresponding block of chrominance samples, the method including: detecting a first prediction direction defined in relation to a first grid of a first aspect ratio in respect of a set of current samples to be predicted; and applying a direction mapping to the prediction direction to generate a second prediction direction defined in relation to a second grid of a different aspect ratio. | 03-19-2015 |
20150085924 | QUANTIZATION FOR DIFFERENT COLOR SAMPLING SCHEMES - A video coding or decoding method operable to generate blocks of quantized spatial frequency data by quantizing the video data according to a selected quantization step size and a matrix of data modifying the quantization step size for use at different respective block positions within an ordered block of samples, the method being operable with respect to at least two different chrominance subsampling formats, and includes for at least one of the chrominance subsampling formats, defining one or more quantization matrices as one or more predetermined modifications with respect to one or more reference quantization matrices defined for a reference one of the chrominance subsampling formats. | 03-26-2015 |
20150117527 | FILTERING OF PREDICTION UNITS ACCORDING TO INTRA PREDICTION DIRECTION - A video coding or decoding method in which luminance and chrominance samples in a 4:4:4 format or a 4:2:2 format are predicted from other respective samples according to a prediction direction associated with blocks of samples to be predicted; comprises detecting a prediction direction in respect of a current block to be predicted; generating a predicted block of chrominance samples according to other chrominance samples defined by the prediction direction; if the detected prediction direction is substantially vertical, filtering the left column of samples in the predicted block of chrominance samples, or if the detected prediction direction is substantially horizontal, filtering the top row of samples in the predicted block of chrominance samples; and encoding a difference between the filtered predicted chrominance block and the actual chrominance block or applying a decoded difference to the filtered predicted chrominance block so as to encode or decode the block respectively. | 04-30-2015 |