Abstract: A method and device for dithering video from a decoder. The method and device provide: selecting a segment of video frames from the video; computing a noise map for the segment of the video, the noise map computed from differences among pixels selected from spatially-distributed sampling patterns in the segment; determining contours of quantization artifacts within the video frame based on the noise map and a histogram of pixel values in the video frame; computing a gradient measurement of pixel values along the contours; identifying regions along the contours of quantization artifacts to apply dithering based on the noise map and the gradient measurement; determining a dithering strength based on the noise map and the gradient measurement; and applying dithering noise to the identified regions at the determined dithering strength.

Abstract: Techniques for encoding data based at least in part upon an awareness of the decoding complexity of the encoded data and the ability of a target decoder to decode the encoded data are disclosed. In some embodiments, a set of data is encoded based at least in part upon a state of a target decoder to which the encoded set of data is to be provided. In some embodiments, a set of data is encoded based at least in part upon the states of multiple decoders to which the encoded set of data is to be provided.

Abstract: A video coding and transmission system may employ techniques for adapting buffered video to network condition changes. Video data may be coded as reference data and non-reference data. According to the embodiments, non-reference frame may be detected in buffered video while awaiting transmission to a network. When network degradation is detected, one or more of the buffered non-reference frames may be dropped when network degradation is detected. Information about the dropped frames may be passed to an encoder for updating buffer parameters for future encoding. In this manner, a video coding system may provide faster responses to changing network conditions than systems without such buffer management techniques.

Abstract: Embodiments of the present invention provide a control system for video processes that selectively control the operation of motion stabilization processes. According to the present invention, motion sensor data indicative of motion of a mobile device may be received and processed. A determination may be made by comparing processed motion sensor data to a threshold. Based on the determination, motion stabilization may be suspended on select portions of a captured video sequence.

Abstract: Techniques for encoding data based at least in part upon an awareness of the decoding complexity of the encoded data and the ability of a target decoder to decode the encoded data are disclosed. In some embodiments, a set of data is encoded based at least in part upon a state of a target decoder to which the encoded set of data is to be provided. In some embodiments, a set of data is encoded based at least in part upon the states of multiple decoders to which the encoded set of data is to be provided.

Abstract: A video coding system and method for increasing a transmitted output bit rate of a video encoding system by altering the content of the bit stream. A video encoder may receive a coding mode signal from a computer application for coding source video data, the coding mode signal indicating a target bit rate having a risk factor related to transmission error associated to the target bit rate. The coded bitstream may be modified based on the risk factor indicated in the coding mode signal. A modified coded bitstream may be outputted at the target bit rate and at a reduced coding efficiency, and the channel may be tested for transmission errors. Based on the test results, a revised coding mode signal indicating the same target bit rate, but a revised risk factor may be provided. The coded bitstream may be revised by removing the modifications previously made to the coded bitstream and a revised coded bitstream having greater coding efficiency may be output at the target bit rate.

Abstract: Methods, systems, and apparatus are presented for reducing distortion in an image, such as a video image. A video image can be captured by an image capture device, e.g. during a video conferencing session. Distortion correction processing, such as the application of one or more warping techniques, can be applied to the captured image to produce a distortion corrected image, which can be transmitted to one or more participants. The warping techniques can be performed in accordance with one or more warp parameters specifying a transformation of the captured image. Further, the warp parameters can be generated in accordance with an orientation of the image capture device, which can be determined based on sensor data or can be a fixed value. Additionally or alternatively, the warp parameters can be determined in accordance with a reference image or model to which the captured image should be warped.

Abstract: A video coding system reduces perceptible artifacts introduced to coded video due to selection of disparate coding modes among adjacent partitions of video. When coding modes are assigned to partitions of video that likely would introduce visually perceptible coding artifacts during decode, the partitions may be subject to a coding process in which a selected partition is coded according to coding modes that correspond to neighboring partitions, then decoded. The decoded data of the selected partition may be recoded according to a different coding mode. Coding artifacts that otherwise might be introduced by the different coding mode may be avoided by first coding the corresponding partition in a manner that is consistent with neighboring partitions, then decoding the coded partition and re-coding the decoded data according to the different mode. In an embodiment, a quantization parameter may be reduced between a first code and the recode. The coding technique may be applied to partitions of various scales—e.

Abstract: A video decoder system includes a video decoding engine, noise database, artifact estimator and post-processing unit. The video coder may generate recovered video from a data stream of coded video data, which may have visually-perceptible artifacts introduced as a byproduct of compression. The noise database may store a plurality of previously developed noise patches. The artifact estimator may estimate the location of coding artifacts present in the recovered video and select noise patches from the database to mask the artifacts and the post-processing unit may integrate the selected noise patches into the recovered video. In this manner, the video decoder may generate post-processed noise which may mask artifacts that otherwise would be generated by a video coding process.

Abstract: A method and system are provided to encode a video sequence into a compressed bitstream. An encoder receives a video sequence from an image-capture device, together with metadata associated with the video sequence, and codes the video sequence into a first compressed bitstream using the metadata to select or revise a coding parameter associated with a coding operation. Optionally, the video sequence may be conditioned for coding by a preprocessor, which also may use the metadata to select or revise a preprocessing parameter associated with a preprocessing operation. The encoder may itself generate metadata associated with the first compressed bitstream, which may be used together with any metadata received by the encoder, to transcode the first compressed bitstream into a second compressed bitstream.

Abstract: A method and system are provided to encode a video sequence into a compressed bitstream. An encoder receives a video sequence from an image-capture device, together with metadata associated with the video sequence, and codes the video sequence into a first compressed bitstream using the metadata to select or revise a coding parameter associated with a coding operation. Optionally, the video sequence may be conditioned for coding by a preprocessor, which also may use the metadata to select or revise a preprocessing parameter associated with a preprocessing operation. The encoder may itself generate metadata associated with the first compressed bitstream, which may be used together with any metadata received by the encoder, to transcode the first compressed bitstream into a second compressed bitstream.

Abstract: Embodiments of the present invention provides a method and device for processing a source video. The method and device may provide computing an artifact estimation from differences among pixels selected from spatially-distributed sampling patterns in the source video; filtering the source video to produce a filtered version of the source video, computing a blending factor based on the artifact estimation in the source video, and computing an output video by blending the source video and the filtered version of the source video based on the blending factor.

Abstract: A method and device for dithering video from a decoder. The method and device provide: selecting a segment of video frames from the video; computing a noise map for the segment of the video, the noise map computed from differences among pixels selected from spatially-distributed sampling patterns in the segment; determining contours of quantization artifacts within the video frame based on the noise map and a histogram of pixel values in the video frame; computing a gradient measurement of pixel values along the contours; identifying regions along the contours of quantization artifacts to apply dithering based on the noise map and the gradient measurement; determining a dithering strength based on the noise map and the gradient measurement; and applying dithering noise to the identified regions at the determined dithering strength.

Abstract: Example embodiments of the present invention provide a method or device for coding source video. The method or device may provide for a segment of video frames from the source video, computing a noise map for the segment of the source video where the noise map is computed from differences among pixels selected from spatially-distributed sampling patterns in the segment, computing control parameter adjustments based on the noise map, and coding the selected segment of source video according to control parameters generated from a default coding policy and the control parameter adjustments, where the default coding policy includes default control parameters of the encoder.

Abstract: Systems and methods for applying a new quality metric for coding video are provided. The metric, based on the Just Noticeable Difference (JND) distortion visibility model, allows for efficient selection of coding techniques that limit perceptible distortion in the video while still taking into account parameters, such as desired bit rate, that can enhance system performance. Additionally, the unique aspects of each input type, system and display may be considered. Allowing for a programmable minimum viewing distance (MVD) parameter also ensures that the perceptible distortion will not be noticeable at the specified MVD, even though the perceptible distortion may be significant at an alternate distance.

Abstract: Embodiments of the present invention provide systems, methods and apparatuses for generating forward, backward or bi-directional P frames. Prior to encoding a sequence of video frames, P frames within the video sequence can be reordered to include causal and/or non-causal references to one or more reference frames. This allows any block partition of a bi-directional P frame to include a single reference to a reference frame that is temporally displayed either before or after the bi-directional P frame. Compression and visual quality can therefore be improved. Hierarchical frame structures can be constructed using bi-directional P frames to better accommodate low complexity decoding profiles. Multilayered encoded video bitstreams can be generated based on the hierarchical frame structures and can include a first layer of anchor frames and one or more second layers that include bi-directional P frames that reference the anchor frames and/or any frame in any lower level layer.

Abstract: Apparatuses and methods for improving coding processes and coding parameters for coding video data are provided for. A coder may select coding parameters for video data according to a default coding policy. The default coding policy may include selection of prediction modes (e.g., intra-coding or inter-coding) for each pixel group in each frame. A video coder may select some pixel groups in a frame to be coded as refresh pixel groups as an exception to the default assignment policies. The selection of refresh pixel groups may be based on prediction relationships among multiple frames of source video data. The default coding of the refresh pixel groups is then modified to enhanced the coding of the refresh pixel groups. The refresh pixel groups may permit fewer intra (I) frames be sent and/or may improve the quality of the recovered video.

Abstract: Disclosed is an exemplary video coder and method that provide a video decoder control method for analyzing data to schedule coding of the data. Input data may be encoded to a plurality of different encoding. It may be determined if a minimum number of the plurality of different encodings comply with at least one of a bitrate constraint and a computational complexity constraint. An encoding may be selected from the compliant encodings that maximizes the quality of the decoded data. Quality may be determined based on at least one predetermined metric related to the selected encoding; and the selected encoding may be delivered to an output buffer.

Abstract: Embodiments of the present invention provide apparatuses and methods of coding video. The apparatuses and methods may further provide coding a source video sequence according to a block-based coding process, estimating processing capabilities of a target decoder, determining if the estimated processing capabilities are sufficient to perform deblocking filtering. If not sufficient, the apparatuses and methods may provide computing deblocking filter strengths for pixel blocks of the source video sequence to be used at decoding, and transmitting the deblocking filter strengths in a coded video data signal with the coded video data. Moreover, if not sufficient, the apparatuses and methods may provide changing coding parameters including, but not limited to, block sizes, transform sizes, and Qmatrix.

Abstract: Disclosed is a system and method of controlling a video decoder, including a reviewing channel data representing coded video data generated by an encoder to identify parameters of a hypothetical reference decoder (HRD) used by the encoder during coding operations. A parameter representing an exit data rate requirement of a coded picture buffer (CPB) of the HRD is compared against exit rate performance of the video decoder. If the exit rate performance of the video coder matches the exit rate requirement of the HRD, the coded video data is decoded, otherwise, a certain decoding degradation scheme can be applied, including disabling decoder from decoding the coded video data.