Abstract: An image region is identified by forming difference-image pixel values from the chosen image and at least one other image in the image sequence and accumulating those difference-image pixel values horizontally and vertically. Co-located horizontal and vertical accumulations are combined and utilised in identifying the region.

Abstract: Apparatus for interpolating images generates motion vectors having a vector confidence value and has a motion compensated interpolation to use the motion vectors to interpolate a new image from two input images at a position determined by a phase control signal. The vector confidence values are used to generate an interpolation confidence measure. The phase control signal is then modified to offset the position at which the new image is interpolated toward the position of the closer of the two input images, if said interpolation confidence measure reduces.

Abstract: To detect the presence of the left and right constituent images of a stereoscopic image packed within an image frame or within a sequence of image frames, images are unpacked according to each one of said known formats; a candidate measure is formed according to each unpacking and the candidate measures are compared to identify the presence of left and right images packed according to an identified format. The candidate measure may be a low pass filtered measure of the difference between the left and right images and may be a high pass filtered measure of the activity in either the left or the right image.

Abstract: To detect non-uniform spatial scaling of an image in the horizontal direction (for example in 4:3 to 16:9 aspect ratio conversion) the image is divided into regions, for example a middle region and two side regions. A measure of horizontal spatial frequency energy is taken in each region by for example subtracting the values of horizontally adjacent pixels and a comparison is made between measures of horizontal spatial frequency energy for the different regions.

Abstract: The invention concerns digital audio processing and in particular the detection of periods where samples can be deleted or repeated unobtrusively so as to change the average sample-rate or to provide time delay modification. Differences between succeeding sample values are evaluated and compared with a threshold and samples are deleted or repeated where two or more consecutive sample value differences are less than the said threshold value.

Abstract: A frame-rate conversion system having an interpolation mode and a synchronization mode. The synchronization mode is selected when temporal interpolation confidence is and images can be retimed without dropping or repeating of images. The interpolation mode is selected when the measure of temporal interpolation confidence is high or repeating of images. Images are exchanged between a temporal interpolator and a buffer at an exchange rate which is varied in the interpolation mode to optimise the buffer occupancy for retiming of images without dropping or repeating of images in s subsequent synchronization.

Abstract: The invention relates to the analysis of characteristics of audio and/or video signals for the generation of audio-visual content signatures. To determine an audio signature a region of interest for example of high entropy—is identified in audio signature data. This region of interest is then provided as an audio signature with offset information. A video signature is also provided.

Abstract: An image or other sample processor has a resampling filter adapted to provide output samples at an output sampling frequency which can be selected to be higher or lower than the input sampling frequency. The width of the resampling filter aperture is scaled according to either the input sampling frequency or the output sampling frequency so as to obtain the wider of the two possible filter apertures.

Abstract: Systems and methods of rendering a motion image. Input temporal image-samples are temporally interpolated to create the output sequence and an intentional, periodic motion-judder component that is visible when the output temporal image-samples are displayed is introduced.

Abstract: A method of analyzing image data to quantify prior block-based processing comprises processing a set of pixel values derived from the image data to generate a spatial difference profile along a line perpendicular to assumed block edges, the spatial difference profile representing differences between values of pixels spaced spatially in a direction parallel to said line; summing the spatial difference profile in a direction perpendicular to that line; measuring inter-maxima distances in the spatial difference profile to a fractional precision in pixel spacing units; and aggregating measured inter-maxima distances to determine a block size.

Abstract: The invention relates to the analysis of characteristics of audio and/or video signals for the generation of audio-visual content signatures. To determine an audio signature a region of interest for example of high entropy—is identified in audio signature data. This region of interest is then provided as an audio signature with offset information. A video signature is also provided.

Abstract: A method of routing audio or video data. A plurality of source data inputs to input modules are divided into groups and main crosspoint modules receive one group from every input module, and destination data outputs from output modules are divided into groups and each output module receives one group from every main crosspoint module. Input modules send a duplicate of one selected group to a redundant crosspoint module and output modules receive a group from a redundant crosspoint module and can use that group in place of any group from a main crosspoint module.

Abstract: In the creation of video program material, picture composition decisions—especially framing parameters—taken by an operator for small-display presentation of a scene are used the automatic generation of picture composition decisions for a larger display. Framing parameters such as pan, are temporally filtered before being applied to the wider field of view provided for the larger display.

Abstract: In for example the assignment of motion vectors, an array of pixel-to-pixel dissimilarity values is analysed to identify a pixel which has a low pixel-to-pixel dissimilarity value and which has neighbouring pixels which have a low pixel-to-pixel dissimilarity value. The pixel-to-pixel dissimilarity values are filtered with a filter aperture decomposed into two or more sectors with partial filters applied respectively to each sector. Outputs of the partial filters are combining by a non-linear operation, for example taking the minimum from diametrically opposed sectors.

Abstract: To assess picture impairment due to the interpolation of output images from input images, for example in standards conversion, an output image detail measure is compared with an input image detail measure. One of the image detail measures is obtained by interpolation between image detail measures for at least two images.

Abstract: Systems and methods of rendering a motion image. Input temporal image-samples are temporally interpolated to create the output sequence and an intentional, periodic motion-judder component that is visible when the output temporal image-samples are displayed is introduced.

Abstract: A method of processing in an image processor a pair of images intended for stereoscopic presentation to identify left-eye and right-eye images of the pair. The method includes dividing both images of the pair into a plurality of like image regions, determining for each region a disparity value between the images of the pair to produce a set of disparity values, deriving for each region a confidence factor for the disparity value, determining a correlation parameter between the set of disparity values and a corresponding set of disparity values from a disparity model, in which the contribution of the disparity value for a region to the said correlation parameter is weighted in dependence on the confidence factor for that region, and identifying from said correlation parameter the left-eye and right-eye images of the pair, wherein the left eye and right images form a stereoscopic pair.

Abstract: To modify the aspect ratio of images in a video sequence, a measure of image energy is provided at or around each pixel, for example by taking differences between adjacent pixels. A minimum energy path of contiguous pixels is then identified which extends across the image from one edge to another, for example vertically if the width of the picture is to be modified. Information concerning the location of a path in one image is used in the identification of a path in the next image, for example by biasing the energy measure of the path. The aspect ratio of each image is then modified by removing or by replicating the minimum energy path of contiguous pixels.

Abstract: Points of interest are identified in an image to characterise that image by dividing the image tiles, each tile including adjacent pixels. The position of a pixel with an extremum value is determined or located within each tile and that extremal value is ascribed to the tile. A tile with an extremal value which is more extreme than that of all adjacent tiles is identified; and the position within the image of the pixel with the extremum value in that identified tile is selected as the point of interest.

Abstract: A method of correcting dirt or other defects in video or other images in which a region is provisionally corrected, an accumulated gradient measure formed along the periphery of the region with and without correction and the region corrected or not depending on a comparison of the gradient measures.