Abstract: The present disclosure relates to an image processing device and a method that enable easier encoding and decoding of a wider variety of images. The image processing device includes: a setting unit that sets a parameter indicating a setting state of a coding tool required in specifying an extended profile that is an extension of a profile specified in a coding standard for performing encoding on each unit having a recursive hierarchical structure; and an encoding unit that generates an encoded stream by encoding an image in accordance with the parameter set by the setting unit. The present disclosure can be applied to image processing devices that encode image data, for example.

Abstract: A video data encoding method for encoding an array of video data values includes frequency-transforming the video data values according to a frequency transform, to generate an array of frequency-transformed values by a matrix-multiplication process using a transform matrix having a data precision greater than six bits.

Abstract: A video encoding method comprises partitioning each image of a video signal into an array of coding tree units; partitioning the array of coding tree units of each image into a portion pattern of rectangular portions for independent encoding such that the prediction dependencies of samples within a portion do not extend into any other portion and the entropy encoding parameters of one portion are independent of those of any other portion, the portion pattern being such that each row of coding tree units is partitioned into at least two of the portions; encoding the coding tree units within each portion using wavefront parallel processing in which, for each portion, successive rows of coding tree units within the portion are encoded so that encoding dependencies are not broken at row boundaries and encoding parameters are propagated from an intermediate position along each row to the start of the next row of coding tree units; and outputting the encoded coding tree units according to an order with respect to t

Abstract: A data encoding method for encoding an array of data values as data sets and escape codes for values not encoded by the data sets, an escape code including a unary coded portion and a non-unary coded portion, the method including: setting a coding parameter defining a minimum number of bits of a non-unary coded portion; adding an offset value of 1 or more to the coding parameter to define a minimum least significant data portion size; generating one or more data sets indicative of positions, relative to the array of data values, of data values of predetermined magnitude ranges, to encode the value of at least one least significant bit of each data value; generating respective complementary most-significant data portions and least-significant data portions; encoding the data sets; encoding the most significant data portions; and encoding the least-significant portions.

Abstract: A video data decoding apparatus is configured to detect a control flag associated with at least a part of an encoded image for decoding, in which in a lossless mode of operation, a first control flag state enables sample-based angular intra-prediction but disables edge filtering of prediction samples, and a second control flag state disables sample-based angular intra prediction but enables edge filtering of prediction samples; and in a lossy mode of operation, the first control flag state enables residual differential pulse code modulation coding and enables edge filtering of prediction samples, and the second control flag state disables residual differential pulse code modulation coding but enables edge filtering of prediction samples.

Abstract: A method of coding 4:2:2 or 4:4:4 video data comprises predicting luminance and/or chrominance samples of an image from other respective reference samples derived from the same image according to a prediction mode associated with a sample to be predicted, the prediction mode being selected for each of a plurality of blocks of samples, from a set of two or more candidate prediction modes; detecting differences between the samples and the respective predicted samples; selecting a frequency-separation transform from two or more candidate frequency separation transforms according to the prediction mode associated with a current block of samples using a mapping between transform and prediction mode, the mapping between different, as between chrominance and luminance samples, for at least the 4:4:4: format; and encoding the detected differences by frequency-separating the differences, using the selected frequency-separation transform.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A method of video coding in respect of a 4:2:2 chroma subsampling format comprises dividing image data into transform units; in the case of a non-square transform unit, splitting the non-square transform unit into square blocks prior to applying a spatial frequency transform; and applying a spatial frequency transform to the square blocks to generate corresponding sets of spatial frequency coefficients.

Abstract: 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 pr

Abstract: 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 pr

Abstract: A data coding apparatus in which a set of ordered data is encoded includes: an entropy encoder encoding the ordered data, wherein each data item is split into respective data subsets that are encoded by first and second encoding systems so that for a predetermined quantity of encoded data generated in respect of a group of data items by the first encoding system, a variable quantity of zero or more data is generated in respect of that group of data by the second encoding system; and an output data stream assembler generating an output data stream from the encoded data, the output data stream including successive packets of a predetermined quantity of data generated by the first encoding system followed, in a data stream order, by the zero or more data generated by the second encoding system in respect of same data items as encoded by the first encoding system.

Abstract: An image processing apparatus generating output pixel values with respect to pixels of an input image selected in accordance with an image feature direction in the input image and including a comparing mechanism comparing blocks of pixels of the input image, the blocks disposed with respect to a pixel position under test so that a correlation between the blocks would indicate an image feature direction applicable to that pixel position; and a validating mechanism detecting whether an image feature direction may be used to interpolate an output pixel value at the pixel position under test. The validating mechanism: (i) detects whether a detected image feature direction for the pixel position under test meets one or more predetermined directional criteria; and (ii) detects whether pixel values in image regions disposed with respect to the pixel position under test in accordance with possible image feature directions meet one or more predetermined pixel value criteria.

Abstract: An image processing apparatus in which output pixels of an output image are generated with respect to input pixels of an input image, a first subset of the output pixels being identical to respective input pixels and a second subset of the output pixels being derived from respective groups of one or more input pixels. The apparatus includes a spatial filter arrangement for filtering the second subset of pixels, the filter not being applied to filter the first subset of output pixels, the filter arrangement having a response such that high spatial frequencies are attenuated in the output image.

Abstract: A method of image processing for image conversion, comprises the steps of calculating a difference measure of the difference in pixel values between corresponding blocks of a current image field and a preceding image field, calculating a variability measure of the variability of pixel values from at least one of said corresponding blocks, determining whether the difference measure exceeds the variability measure, and if the difference measure exceeds the variability measure, then setting an inter-image mixing value for each pixel in the corresponding block of the current image field to indicate that the current image field should not be mixed with the preceding image field at that pixel position.

Abstract: A method of data processing. The method comprises applying a filter to an input sample set comprising sample values selected from an input sequence of input sample values, so as to generate a corresponding output sample value having an output sample value position with respect to the input sample set, in which the filter has a maximum output range. The method further comprises deriving a permissible output value range from an input group of two or more input sample values in the input sample set which surround the output sample value position, detecting whether the output of the filter is outside the permissible output value range and, if so, limiting the output of the filter to lie within the permissible output value range.

Abstract: An image processing apparatus generating output image pixels from groups of one or more input image pixels, the groups selected in accordance with an image feature direction in the input image. An interpolator interpolates intermediate pixels between the input image pixels, and a block comparator detects correlation between sets of test blocks of pixels in the input image, which sets are oriented with respect to a current pixel position so that the orientation of a set having the greatest correlation indicates a probable image feature direction applicable to the current pixel position. For at least some sets of test blocks having an orientation with respect to the current pixel position within a predetermined range around a vertical orientation, the test blocks include the input image pixels and intermediate pixels interpolated from the input image pixels. For other sets of test blocks, the test blocks include only the input image pixels.

Abstract: A method of image processing for converting interlaced images to progressive scan images comprises the steps of generating a motion dependent mixing value for determining the extent to which a preceding image field should be mixed with a current intra-field interpolated image field at a given pixel position, comparing the generated mixing value with a preceding historical mixing value, and if the comparison indicates an increase in motion, using the generated mixing value; otherwise, if the comparison indicates a decrease in motion, temporally filtering the generated mixing value prior to use.

Abstract: A method of image processing for conversion of an image in a sequence of images comprises the steps of associating pixels of an image with respective motion values indicative of a degree of inter-image motion for each pixel; adjusting the motion value of each pixel based upon the motion value of a secondary pixel found within a first region of a first predetermined size substantially centered upon each respective pixel, said secondary pixel being that whose associated motion value is indicative of the greatest motion of any pixel in the first region; adjusting the motion value of each pixel based upon the motion value of a secondary pixel that lies within a second region of a second predetermined size substantially centered upon each respective pixel, said secondary pixel being that whose associated motion value is indicative of the least motion of any pixel in the second region; categorizing each pixel as a static pixel or a motion pixel according to its respective associated motion value, and then selecting