Abstract: This disclosure provides methods, devices, and systems for image scaling. The present implementations more specifically relate to downscaling techniques that preserve a subset of pixel values in a digital image so that all reconstructed pixel values in the upscaled image can be interpolated based on two or more preserved pixel values. In some aspects, an image downscaler may partition a digital image into a number of image tiles based on a base tile size and one or more scaling factors associated with a downscaling operation used to downscale each image tile. The base tile size indicates the dimensions of the downscaled tiles. The one or more scaling factors indicate distances between the pixel values preserved as a result of one or more iterations, respectively, of the downscaling operation, where each iteration preserves a smaller subset of the pixel values from the original image (as a lower resolution tile).

Abstract: This disclosure provides methods, devices, and systems for video coding. The present implementations more specifically relate to hybrid coding techniques that combine aspects of inter-frame coding with aspects of intra-frame coding. In some aspects, a video encoder may perform inter-frame coding in a weighted manner so that the coded video frames (also referred to as “residual frames”) may include contributions from the current video frame to be transmitted over a communication channel and also may include contributions from the previous video frame transmitted over the communication channel. More specifically, any pixel value (r(n)) in the residual frame can be expressed as a weighted combination of a respective pixel value (x(n)) in the current video frame and a co-located pixel value (x(n?1)) in the previous video frame, where r(n)=x(n)??·x(n?1) and where 0???1 is a scaling factor representing the degree of contribution by the previous video frame.

Abstract: This disclosure provides methods, devices, and systems for video coding. The present implementations more specifically relate to hybrid coding techniques that combine aspects of inter-frame coding with aspects of intra-frame coding. In some aspects, a video encoder may perform inter-frame coding in a weighted manner so that the coded video frames (also referred to as “residual frames”) may include contributions from the current video frame to be transmitted over a communication channel and also may include contributions from the previous video frame transmitted over the communication channel. More specifically, any pixel value (r(n)) in the residual frame can be expressed as a weighted combination of a respective pixel value (x(n)) in the current video frame and a co-located pixel value (x(n?1)) in the previous video frame, where r(n)=x(n)??·x(n?1) and where 0???1 is a scaling factor representing the degree of contribution by the previous video frame.

Abstract: Lightfield displays for generating a 3D image comprise a 2D array of hogels. Each hogel comprises a 2D array of one or more pixels for generating light rays, and a light distribution control arrangement for controlling in 2D the angular distribution of the light rays from the array which are emitted by the hogel. The 2D array of each hogel is arranged to generate light rays which correspond to an elementary image assigned to the hogel, with each elementary image having a central axis which passes through a center of the image and extends perpendicular to the image. A plurality of the hogels have different lateral offsets between the light distribution control arrangement and the central axis of the respective elementary image.

Abstract: This disclosure provides methods, devices, and systems for data compression. The present implementations more specifically relate to lossless data compression techniques that combine entropy coding with run-length encoding of zeroes. In some aspects, an encoder may obtain a sequence of integer values representing a frame of data and may iteratively scan the sequence for runs of zeros. During each iteration of the scan, the encoder may increment a count value (N) if the current integer value is equal to zero or, if the current integer value is not equal to zero, output a pattern of bits representing the current count value or the current integer value. In some implementations, the pattern of bits may include a codeword associated with an entropy encoding scheme. More specifically, the encoder may encode the current integer value as the codeword if N>0 and may encode the current count value as the codeword if N=0.

Abstract: Described are concepts, systems and techniques related to processing an input video signal intended for a first display to produce an output signal appropriate for a second display. The concepts, systems and techniques include converting using one or more transfer functions arranged to provide relative scene light values and remove or apply rendering intent of the input or output video signal, wherein the removing or applying rendering intent alters luminance.

Abstract: Described are concepts, systems and techniques related to processing an input video signal intended for a first display to produce an output signal appropriate for a second display. The concepts, systems and techniques include converting using one or more transfer functions arranged to provide relative scene light values and remove or apply rendering intent of the input or output video signal, wherein the removing or applying rendering intent alters luminance.

Abstract: Described are concepts, systems and techniques related to processing an input video signal intended for a first display to produce an output signal appropriate for a second display. The concepts, systems and techniques include converting using one or more transfer functions arranged to provide relative scene light values and remove or apply rendering intent of the input or output video signal, wherein the removing or applying rendering intent alters luminance.

Abstract: A method of processing a video signal from a higher dynamic range source having a source colour scheme to produce a signal usable by target devices of lower dynamic range having a target colour scheme used as a converter to implement a function. The function provides the received signal as a luminance component and separate colour components for each pixel and determines a maximum allowable luminance value for the colour components in the lower dynamic range scheme. A compression function is applied to the luminance component of each pixel. The compress luminance component and separate colour components are then provided as an output signal in the target colour scheme. The compression function depends upon the maximum allowable luminance value for the corresponding colour components of each pixel. In this way, the arrangement ensure no colours are distorted in the target lower dynamic range scheme.

Abstract: Described are concepts, systems and techniques related to processing an input video signal intended for a first display to produce an output signal appropriate for a second display. The concepts, systems and techniques include converting using one or more transfer functions arranged to provide relative scene light values and remove or apply rendering intent of the input or output video signal, wherein the removing or applying rendering intent alters luminance.

Abstract: A technique is disclosed for estimating the measurement error in motion vectors used for example in a motion compensated video signal process. For each motion vector corresponding to a region of an image a plurality of temporal and spatial image gradients are calculated corresponding to that region. From the constraint equations of the image gradients a plurality of error values can be calculated for each motion vector and a parameter generated describing the size of the distribution of motion vector measurement errors. Subsequent processing of the video signals using the motion vectors can then be adapted, for example by graceful fallback in motion compensated interpolation, depending on the accuracy of each motion vector. The ‘confidence’ in the accuracy of each motion vector can be described by a parameter calculated in relation to the size of the error distribution and the motion vector speed.

Abstract: A technique for generating motion vectors for applications is requiring field of frame rate interpolation and especially in standards conversion. The image gradients on the same standard as the input video or film signal and then vertical/temporal interpolators are used to convert to the output standard before determining the motion vectors. This allows motion vectors to be easily calculated on the output standard.

Abstract: This invention provides a way of performing improved motion compensated interpolation of moving images, such as television, using motion vectors of variable reliability. By taking into account the reliability of the motion vectors, produced by a separate motion estimation device, a subjectively pleasing interpolation can be produced. This is in contrast to simple motion compensated interpolation, taking no account of motion vector reliability, which is often degraded by objectionable switching artifacts due to unreliable motion vectors. The invention can be used, for example, to improve the performance of motion compensated standards converters used for converting between television standards with different picture rates. The invention allows a gradual transition between motion compensated and non-motion compensated interpolation depending on the reliability of the motion vector used.

Abstract: A technique for generating motion vectors in video and film signal processing uses constraint equation based motion estimation. Simplifications of the processing and hardware are made possible by generating motion vectors based on the normalized constraint equation. The temporal and spatial image gradients are calculated using temporal and spatial differentiators (16, 17, 18). An angle (&thgr;) corresponding to the orientation of the spatial image gradient vector and the motion speed (vn) in the direction of the vector are calculated using apparatus including a rectangular to polar coordinate converter (32). &thgr; and vn are the parameters of the normalized constraint equation.

Abstract: A high speed analog-to-digital converter utilizes a fine resolution ADC to digitize the low band component of an analog video signal to produce a fine resolution signal and a coarse resolution ADC to digitize the full spectrum of the analog signal and produce a coarse resolution signal. The coarse resolution signal is subtracted from the fine resolution signal to generate a summed signal containing a quantization error, which is filtered through a low pass digital filter to filter out the high band component and pass the quantization error. The filter output is summed with the coarse resolution signal to restore the fine resolution of the low band, producing a digital output signal that has a resolution suitable for high definition applications.

Abstract: This invention provides a way of performing improved motion compensated interpolation of moving images, such as television, using motion vectors of variable reliability. By taking into account the reliability of the motion vectors, produced by a separate motion estimation device, a subjectively pleasing interpolation can be produced. This is in contrast to simple motion compensated interpolation, taking no account of motion vector reliability, which is often degraded by objectionable switching artifacts due to unreliable motion vectors. The invention can be used, for example, to improve the performance of motion compensated standards converters used for converting between television standards with different picture rates. The invention allows a gradual transition between motion compensated and non-motion compensated interpolation depending on the reliability of the motion vector used.

Abstract: Method of motion-compensated video processing such as standards conversion, uses motion vectors assigned on a pixel-by-pixel basis. The pixels of an input video signal are written to locations in a video store determined by the motion vector assigned to that pixel. Multiple vectors can address a single written pixel to enable mixing of backward and forward vectors. A confidence value governs the accumulation of pixels and the later interpolation between motion compensated fields.