Abstract: This disclosure describes techniques for encoding digital video data using interpolation filters and offsets. An encoder may be configured to select interpolation filters for sub-pixel precision motion estimation based on historical interpolation results obtained for previously encoded video units, such as frames or slices. The encoder also may be configured to compute and assign offsets to the sub-pixel positions after interpolation based on differences between a reference unit and the unit to be coded. The computation and assignment of offsets may be performed before motion estimation. Motion estimation may be refined so that the motion search considers sub-pixel positions to which offsets have been previously added and evaluates sub-pixel positions that have a non-zero offset. In some cases, interpolation filter selection, offset computation, and/or refined motion estimation for a given unit may be performed in a single encoding pass.

Abstract: During a video coding process, a prediction block is generated for a CU. The CU has two or more prediction units. A computing device determines, based on sizes of one or more of the prediction units, whether to perform a smoothing operation on samples in a transition zone of the prediction block. The transition zone is located at a boundary between samples of the prediction block associated with different prediction units. If the computing device makes the determination to perform the smoothing operation, the smoothing operation is performed to smooth samples of the prediction block in the transition zone.

Abstract: Apparatus and methods of using content information for encoding multimedia data are described. A method of processing multimedia data includes obtaining content information of multimedia data, and encoding the multimedia data so as to align a data boundary with a frame boundary in a time domain, wherein said encoding is based on the content information. In another aspect, a method of processing multimedia data includes obtaining a content classification of the multimedia data, and encoding blocks in the multimedia data as intra-coded blocks or inter-coded blocks based on the content classification to increase the error resilience of the encoded multimedia data. Apparatus that can process multimedia data described in these methods are also disclosed.

Abstract: An offset can be applied to intermediate values obtained while performing an interpolation filtering operation such that applying the offset reduces the bitdepth of the intermediate value. The intermediate value can be stored with the reduced bitdepth, and when retrieved, the offset can be added back such that future calculation can be performed using the intermediate value with the original bitdepth.

Abstract: Methods and apparatus to process multimedia data enabling efficient partial decoding of transform coded data are described. A decoder device receives transform coefficients, where the transform coefficients are associated with multimedia data. The decoder device determines a set of multimedia samples to be reconstructed. In one aspect, the set of samples to be reconstructed is a subset of a matrix of transformed multimedia samples. The decoder device determines a set of transform coefficients to be used to reconstruct the multimedia samples. In one aspect, the transform coefficients are used to scale partial basis images associated with the encoding method used to generate the transform coefficients, resulting in reconstructed multimedia samples.

Abstract: Techniques are described for encoding and decoding digital video data using macroblocks that are larger than the macroblocks prescribed by conventional video encoding and decoding standards. For example, the techniques include encoding and decoding a video stream using macroblocks comprising greater than 16×16 pixels. In one example, an apparatus includes a video encoder configured to encode a coded unit comprising a plurality of video blocks, wherein at least one of the plurality of video blocks comprises a size of more than 16×16 pixels and to generate syntax information for the coded unit that includes a maximum size value, wherein the maximum size value indicates a size of a largest one of the plurality of video blocks in the coded unit. The syntax information may also include a minimum size value. In this manner, the encoder may indicate to a decoder the proper syntax decoder to apply to the coded unit.

Abstract: A method for color blending prevention in video coding may include selecting, in a mode decision phase of an encoding of a current video frame, to encode an output bitstream in skip mode, wherein the skip mode includes altering encoding of the coding unit by setting luma component transform coefficients for the coding unit to zero, revaluating the selection of the skip mode based on quantized chroma coefficients, the quantized chroma coefficients generated from transformed and quantized residual chroma components, confirming the selection of the skip mode when there are no non-zero quantized chroma coefficients, and revoking the selection of the skip mode when there are non-zero quantized chroma coefficients, wherein the non-zero quantized chroma coefficients are transmitted when the selection of the skip mode is revoked.

Abstract: In one example, an apparatus includes a video encoder configured to partition a block of video data into a first partition and a second partition using a geometric motion partition line, calculate a prediction value of a pixel in a transition region of the block using a filter that applies a value for at least one neighboring pixel from the first partition and a value for at least one neighboring pixel from the second partition, calculate a residual value of the pixel in the transition region of the block based on the prediction value of the pixel in the transition region, and output the residual value of the pixel. In one example, a video decoder may use a similar filter to decode an the encoded block after receiving the residual value for the encoded block, and using a definition of the geometric motion partition line.

Abstract: Methods and systems for encoding multimedia content with enforcement of commercial advertisements are discussed in the disclosure. Some of the methods may require all or part of a commercial advertisement segment to be viewed and/or decoded in order to decode an entertainment segment. In some implementations, the disclosure provides for inserting commercial advertisements in a video stream. The various implementations discussed herein may require a viewer to watch all or part of a commercial segment in order to view an entertainment segment of multimedia content.

Abstract: This disclosure relates to techniques for constructing a combined reference picture list, List C, based on List 0 and List 1, used for uni-directional prediction of video blocks in any direction. The techniques include coding one or more syntax elements defined to indicate construction information for List C, and performing reference picture list construction for List C from List 0 and List 1 based on the syntax elements. The one or more syntax elements may indicate that List C is used for uni-directional prediction, and may also indicate a number of reference pictures identified in List C and a reference index of a reference picture for each entry in List C. Each coded video block of a B slice may have an associated syntax element, i.e., inter_pred_idc, to indicate whether the video block is bi-predicted from List 0 and List 1 (Bi) or uni-directional predicted from List C (Pred_LC).

Abstract: The example techniques described in this disclosure provide for an efficient manner to encode or decode a video block of a picture using a single reference picture list. The single reference picture list may include identifiers for reference picture or pictures used to encode or decode the video block. In some examples, a video encoder or decoder may encode or decode a video block that is predicted from two reference pictures using the single reference picture list, and encode or decode a video block that is predicted from one reference picture using the same, single reference picture list.

Abstract: This disclosure describes techniques for quantizing coefficients of a video block for a video coding process that supports context-based adaptive binary arithmetic coding (CABAC). A method may comprise estimating a last non-zero coefficient of the video block, and generating a set of quantized coefficients for the video block based on an assumption that the estimated last non-zero coefficient is actually the last non-zero coefficient of the video block.

Abstract: This disclosure describes various interpolation techniques performed by an encoder and a decoder during the motion compensation process of video coding. In one example, an encoder interpolates pixel values of reference video data based on a plurality of different pre-defined interpolation filters. In this example, the decoder receives a syntax element that identifies an interpolation filter, and interpolates pixel values of reference video data based on the interpolation filter identified by the syntax element. In another example, a method of interpolating predictive video data includes generating half-pixel values based on integer pixel values, rounding the half-pixel values to generate half-pixel interpolated values, storing the half-pixel values as non-rounded versions of the half-pixel values, and generating quarter-pixel values based on the non-rounded versions of the half-pixel values and the integer pixel values.

Abstract: Techniques are described for encoding and decoding digital video data using macroblocks that are larger than the macroblocks prescribed by conventional video encoding and decoding standards. For example, the techniques include encoding and decoding a video stream using macroblocks comprising greater than 16×16 pixels. In one example, an apparatus includes a video encoder configured to encode a coded unit comprising a plurality of video blocks, wherein at least one of the plurality of video blocks comprises a size of more than 16×16 pixels and to generate syntax information for the coded unit that includes a maximum size value, wherein the maximum size value indicates a size of a largest one of the plurality of video blocks in the coded unit. The syntax information may also include a minimum size value. In this manner, the encoder may indicate to a decoder the proper syntax decoder to apply to the coded unit.

Abstract: Source and destination video devices may use data structures that signal details of an operation point for an MPEG-2 (Motion Picture Experts Group) System bitstream. In one example, an apparatus includes a multiplexer that constructs a data structure corresponding to a multiview video coding (MVC) operation point of an MPEG-2 (Motion Picture Experts Group) System standard bitstream, wherein the data structure signals a rendering capability value that describes a rendering capability to be satisfied by a receiving device to use the MVC operation point, a decoding capability value that describes a decoding capability to be satisfied by the receiving device to use the MVC operation point, and a bitrate value that describes a bitrate of the MVC operation point, and that includes the data structure as part of the bitstream, and an output interface that outputs the bitstream comprising the data structure.

Abstract: In general, this disclosure provides techniques for quantization of the coefficients of video blocks in a manner that can achieve a desirable balance of rate and distortion. The described techniques may analyze a plurality of quantization levels associated with each individual coefficient to select the quantization level for the individual coefficients that results in a lowest coding cost. Since CAVLC does not encode each coefficient independently, the techniques may compute the coding costs for each of the candidate quantization levels associated with the individual coefficients based on quantization levels selected for previously quantized coefficients and estimated (or predicted) quantization levels for subsequent coefficients of a coefficient vector. The quantization levels for each of the coefficients are selected based on computed coding costs to obtain a set of quantized coefficients that minimize a rate-distortion model.

Abstract: In one example, a device for coding video data includes a video coder configured to configured to code information representative of whether an absolute value of an x-component of a motion vector difference value for a current block of video data is greater than zero, code information representative of whether an absolute value of a y-component of the motion vector difference value is greater than zero, when the absolute value of the x-component is greater than zero, code information representative of the absolute value of the x-component, when the absolute value of the y-component is greater than zero, code information representative of the absolute value of the y-component, when the absolute value of the x-component is greater than zero, code a sign of the x-component, and when the absolute value of the y-component is greater than zero, code a sign of the y-component.

Abstract: Apparatus and methods of using content information for encoding multimedia data are described. A method of processing multimedia data includes A method of processing multimedia data, including obtaining content information of multimedia data, and encoding the multimedia data to form an encoded bitstream, said encoding comprising inserting at least one redundant block of intra-coded data into the encoded bitstream based on the content information. In some aspects, the encoding comprises encoding the multimedia data into a base layer and an enhancement layer, and wherein the intra-coded data is encoded using the quantization parameter for the base layer. In other aspects, the intra-coded data is encoded using the quantization parameter for the enhancement layer.

Abstract: Apparatus and methods of using content information for encoding multimedia data are described. A method of processing multimedia data includes receiving multimedia data, and encoding the multimedia data into a first data group and a second data group based on content of the multimedia data, the first data group being configured to be independently decodable from the second data group, and wherein the first and second data groups are encoded at different quality levels. The method can also include classifying the content of the multimedia data and encoding the multimedia data based on the content classification.

Abstract: Apparatus and methods of using content information for encoding multimedia data are described. A method of processing multimedia data includes obtaining content information of multimedia data, and encoding the multimedia data so as to align a data boundary with a frame boundary in a time domain, wherein said encoding is based on the content information. In another aspect, a method of processing multimedia data includes obtaining a content classification of the multimedia data, and encoding blocks in the multimedia data as intra-coded blocks or inter-coded blocks based on the content classification to increase the error resilience of the encoded multimedia data. Apparatus that can process multimedia data described in these methods are also disclosed.