Abstract: Embodiments of the invention provide a screen sharing technology including a local computing device and a remote computing device. The local computing device compresses pixel data captured from a frame buffer of the local computing device into a video stream. When the local computing device determines that a video visual component is to be displayed, it obtains compressed data for the video visual component, location information and temporal information. The remote computing device decodes the compressed data and the video stream in different decoder and displays the video stream and compressed data on its monitor according to the temporal information and location information. As such, the embodiment described above leads to better coding efficiency, better coding quality, and lower bit rate.

Abstract: A video codec including a memory and a processor operably coupled to the memory. The processor is configured to compute a reconstructed pixel based on a residual pixel and a first prediction pixel and compute a second prediction pixel in a directional intra prediction mode based on the reconstructed pixel, where the first and second prediction pixels are located in a same block of a video frame. A method for intra prediction including computing a prediction pixel adaptively based on a plurality of reconstructed neighboring pixels, where a distance between the prediction pixel and each of the plurality of reconstructed neighboring pixels is one.

Abstract: An encoding apparatus and coding methods. The method includes receiving a video frame including screen content, generating a block containing an index map of colors for screen content in the video frame, wherein the block includes strings of index values, encoding one or multiple consecutive index values in a first string of index values using same escape colors index values and a run value identifying how many of the same escape color index values have been consecutively encoded, where the escape colors index values represent escape colors, and where the escape colors are colors not included in a palette corresponding to the block, sequentially encoding the escape colors corresponding to the one or multiple consecutive index values after all of the strings of index values of the block have been encoded, and transmitting the strings of index values and the escape colors in a bitstream to a decoding apparatus.

Abstract: Presented systems and methods facilitate screen content coding. A system can comprises: a processing component configured to execute coding operations and a storage component configured to store information for the processing component, including the color table and color index map. The coding operations can include: receiving information associated with a plurality of pixels; creating a color table, the color table includes color values (e.g., of the pixels) and corresponding indices; creating a color index map wherein each index of the color map maps a pixel to an index value of the color table; and performing coding operations corresponding to the color table and color index map. In one exemplary implementation, index values of the color table are encoded/decoded during color table and index map coding rather than the actual raw color values for each pixel. Various types of compression and coding can be implemented (e.g., lossless, lossy, intra-prediction, inter-prediction, etc.).

Abstract: Embodiments are provided for compressing a color index map in video coding applications including screen content images. An embodiment method includes obtaining, at a video codec device, an image block, and generating a color index map comprising a plurality of entries and representing the image block. Each one of the entries is assigned a color index indicating a respective color. The method further includes assigning, in a correct prediction map, a first bit-value for each one of the entries that is predictable by a neighboring entry in the color index map, and a second bit-value for each one of the entries that is unpredictable by any neighboring entry in the color index map. Further, an actual value from the color index map for the each one of the entries that is unpredictable by any neighboring entry is added in a sequence of non-predictable color indices.

Abstract: An encoding apparatus, decoding apparatus, and coding methods. The encoding apparatus includes a processor configured to receive a video frame including screen content, generate a block containing an index map of colors for screen content in the video frame, wherein the block includes strings of index values sharing a same escape color index value, wherein the escape color index value represents an escape color, encode each of the strings of index values in the block, and sequentially encode the escape colors after each of the strings of index values in the block has been encoded. A transmitter operably coupled to the processor is configured to transmit the strings of index values and the escape colors in a bitstream to a decoding apparatus.

Abstract: There are provided video encoders, video decoders, and corresponding methods. A video encoder for encoding video signal data for an image block includes an encoder (100) for encoding all color components of the video signal data using a common predictor (315). A video decoder for decoding video signal data for an image block includes a decoder (200) for decoding all color components of the video signal data using a common predictor (430). Additionally, an apparatus and method for encoding and decoding signal data for an image block includes an encoder and decoder for encoding/decoding color components of the video signal data without applying a residual color transform thereto. Furthermore, a video encoder and decoder for encoding/decoding video signal data for an image block includes an encoder and decoder for encoding/decoding the video signal data using unique predictors for each of color components of the video signal data.

Abstract: There are provided methods and apparatus for using syntax for the coded_block_flag syntax element for the CAVLC 4:4:4 Intra, High 4:4:4 Intra, and High 4:4:4 Predictive profiles in MPEG-4 AVC high level coding. An apparatus includes an encoder (100) for encoding image data into a resultant bitstream in accordance with an encoding profile that encodes a sample of the image data such that the sample includes two chrominance arrays and a luminance array. Each of the two chrominance arrays has a same height and a same width as the luminance array. The encoder (100) indicates a presence of at least one 8×8 block in the resultant bitstream using a syntax element.

Abstract: An encoding apparatus includes a processor configured to receive a video frame including screen content and generate a block containing an index map of colors for screen content in the video frame. The block includes a first string of index values and a second string of the index values immediately below the first string. The processor is also configured to encode a second string palette_run_type flag corresponding to the second string without referencing a first string palette_run_type flag corresponding to the first string and using a single available context. A transmitter operably coupled to the processor is configured to transmit the second string palette_run_type flag in a bitstream to a decoding apparatus.

Abstract: A decoding method including receiving a bitstream corresponding to a residual block, decoding the residual block having a plurality of residual pixels represented as transform coefficients, and computing a reconstructed block based on the residual pixels. The reconstructed block includes reconstructed pixels and uses an intra prediction mode to generate prediction pixels in sequence vertically or horizontally based on reconstructed pixels in the reconstructed block. The reconstructed block includes initial reconstructed pixels based on initial prediction pixels. The intra prediction mode is used to generate the initial prediction pixels based on external reference pixels located in neighboring blocks decoded before the reconstructed block. Computing the reconstructed block includes combining prediction pixels with residual pixels to generate additional reconstructed pixels used to generate additional prediction pixels.

Abstract: A method for video encoding comprising transforming a plurality of pixels to generate a first plurality of transform coefficients, quantizing the first plurality of transform coefficients to generate a plurality of quantized transform coefficients, computing a plurality of prediction pixels based on a plurality of reconstructed pixels which are prediction references for the plurality of pixels, transforming the plurality of prediction pixels to generate a second plurality of transform coefficients, and computing a plurality of prediction residual coefficients as a difference between the plurality of quantized transform coefficients and the second plurality of transform coefficients.

Abstract: An encoding apparatus, decoding apparatus, and coding methods are provided.

Abstract: The present disclosure provides a method and an apparatus for rounding a coordinate value of a non-integer pixel position motion vector. The method includes: rounding a coordinate value of a non-integer pixel position motion vector, which includes: for each dimension of coordinates of the non-integer pixel position motion vector, when a coordinate in the dimension is a non-integer pixel position, rounding the coordinate value of the non-integer pixel position motion vector in the dimension to one of integer pixel coordinate positions A and B if distances from the coordinate of the non-integer pixel position motion vector in the dimension to the integer pixel coordinate positions A and B adjacent to the non-integer pixel position in the dimension are the same, where an integer pixel coordinate position is determined by a sign of the coordinate value of the non-integer pixel position motion vector in the dimension.

Abstract: A method and a device for coding and decoding images are disclosed. The method for coding images includes: determining a second length according to a direction of a division line, a scale value, and a position parameter value; determining a division mode of the image block according to the direction of the division line, a first length, the second length, and the scale value; coding the image block according to the division mode of the image block; and coding a direction parameter value, the scale value, and the position parameter value. With the technical solution provided in the embodiments of the present invention, the determining of the division mode of the image block on the image coder is simplified.

Abstract: An apparatus comprising a processor configured to receive a video frame comprising a current block, wherein the current block comprises a plurality of original pixels, compute a plurality of reconstructed pixels based on the original pixels, and use an intra prediction mode to generate a set of prediction pixels based on a set of reconstructed pixels in the plurality of reconstructed pixels.

Abstract: A video codec comprising a processor configured to compute a difference between an original pixel and a prediction pixel to generate a prediction residual, and binarize an absolute value of the prediction residual. A method for video coding comprising computing a difference between an original pixel and a prediction pixel to generate a prediction residual, and binarizing an absolute value of the prediction residual. A video encoder comprising a processor configured to set a number of syntax elements to indicate lossless encoding of some or all coding units (CU) in a video frame, a transmitter configured to transmit a bit stream comprising the syntax elements. A method for video encoding comprising setting a number of syntax elements to indicate lossless encoding of some or all coding units (CU) in a video frame, and transmitting a bit stream comprising the syntax elements.

Abstract: There are provided methods and apparatus for parallel implementations of 4:4:4 coding. A video encoder for encoding video signal data for an image block includes an encoder for encoding all color components of the image block by selecting a common block partition and a common spatial prediction mode. The common block partition and the common spatial prediction mode are selected by concurrently evaluating all of the color components in parallel.

Abstract: A method and device for generating a predicted value of image that are mostly used to generate a predicted value of a current block during image encoding or decoding. The method includes: determining a searching scope, wherein multiple motion vectors are included in the searching scope; performing up-sampling interpolations on first reference blocks, corresponding to the motion vector in the searching scope, in a reference image of the current block by using a first filter to obtain up-sampled first reference blocks; by using the up-sampled first reference blocks, obtaining at least one candidate motion vector corresponding to the current block; performing up-sampling interpolations on second reference blocks, corresponding to the at least one candidate motion vector, in the reference image of the current block by using a second filter to obtain up-sampled second reference blocks; combining the up-sampled second reference blocks to obtain a predicted value of the current block.

Abstract: Embodiments of the present invention provide a method and an apparatus for decoding and encoding a video, and a method and an apparatus for predicting a direct current coefficient. The video decoding method includes: receiving current frame image information sent by an encoding end, where the current frame image information includes prediction value information, and the prediction value information includes at least one intra-frame direct current DC prediction value; selecting a prediction value from the at least one intra-frame DC prediction value in the prediction value information as an intra-frame DC prediction value of the current image. Through the embodiments of the present invention, flexibility of encoding and decoding a video can be improved.

Abstract: Embodiments are provided for compressing a color index map in video coding applications including screen content images. An embodiment method includes obtaining, at a video codec device, an image block, and generating a color index map comprising a plurality of entries and representing the image block. Each one of the entries is assigned a color index indicating a respective color. The method further includes assigning, in a correct prediction map, a first bit-value for each one of the entries that is predictable by a neighboring entry in the color index map, and a second bit-value for each one of the entries that is unpredictable by any neighboring entry in the color index map. Further, an actual value from the color index map for the each one of the entries that is unpredictable by any neighboring entry is added in a sequence of non-predictable color indices.