Abstract: Frame-level dependent bit allocation for hybrid video coding is presented to address issues relating to computational complexity of multi-pass coding of video data. An interframe dependency (IFDM) approach is presented which enables a quantitative measure of the coding dependency between the current frame and its reference frame. Based on the IFDM, buffer-constrained frame-level dependent bit allocation is determined (IFDM-DBA). Successive convex approximation techniques are utilized to convert an original optimization into a series of convex optimization problems.

Abstract: Efficient encoding and/or decoding of digital video is provided using multiple candidate reference frames, making playback of the digital video optionally reversible. For example, a source can be encoded as duplex coded frames having multiple candidate reference frames. The reference frames can be previous or future frames, and the duplex coded frames can be encoded at a bit-rate that ensures lossless decoding using any of the candidate reference frames. Therefore, the duplex coded frames can encoded in normal and/or reverse temporal order. In this regard, the ability to decode digital video frames using either a single previous or future frame enables reversible digital video, bit-stream switching and video splicing arbitrary time points, and provides for increased error resilience.

Abstract: System and methodologies are provided herein for reconstructing a video signal from multiple video streams. Various aspects described herein can utilize a least square estimate (LSE) algorithm to jointly decode multiple video bitstreams that are generated from a common original video sequence at different bit rates. As described herein, the LSE algorithm can reconstruct an original video sequence by determining and computing a weighted sum of collocated video information reconstructed from different video bitstreams. The weights applied can be adaptively determined to minimize the mean square error (MSE) of the reconstructed video sequence as compared to the original.

Abstract: The claimed subject matter relates to an architecture that can facilitate more efficient free view generation in Ray-Space by way of a Radon transform. The architecture can render virtual views based upon original image data by employing Ray-Space interpolation techniques. In particular, the architecture can apply the Radon transform to a feature epipolar plane image (FEPI) to extract more suitable slope or direction candidates. In addition, the architecture can facilitate improved block-based matching techniques in order to determine an optimal linear interpretation direction.

Abstract: Data encoding and/or decoding techniques are applied in a codec system. Pixel parameters and error thresholds can be determined. A prediction mode can be determined. Further, a prediction mode can predict values of an encoded and/or decoded media item. In one aspect, compositions of media items can determine prediction modes.

Abstract: A method for encoding video includes receiving data, and encrypting the data using at least four Huffman trees. A method for encoding video includes receiving data, and encrypting the data such that an internal state of a stream cipher is independent of plaintext and ciphertext. A video encoding system for encoding video in a computing environment includes means for accessing data, and means for encrypting the data such that there are approximately 2106 possibilities.

Abstract: The quantization factor for each block of pixels in an image or video encoding or transcoding method is determined. The blocks of pixels are classified according to predefined criteria and the blocks are processed according to the resulting classification. The predefined criteria include, for example, anticipated characteristics of the blocks after quantization, such as the transform coefficients after quantization and/or the total number of non-zero transform coefficients.

Abstract: An optimal denoising method for video coding. This method makes use of very few pixels and linear operations, and can be embedded into the motion compensation process of video encoders. This method is simple and flexible, yet offers high performance and produces appealing pictures.

Abstract: This invention relates to method and apparatus for subpixel-based down-sampling. This invention implements an adaptive filter 140 based on edge detection, which removes visible color fringing artifacts while efficiently retaining sharpness.

Abstract: Systems and methodologies for concealing frame loss in a video transmission environment are provided herein. Multiple Description Coding (MDC) can be used as an Error Resilience technique for video coding. In case of transmission errors, Error Concealment can be combined with MDC to reconstruct a lost frame, such that the propagated error to following frames can be reduced. Further, multi-hypothesis decoding can be employed to enhance reconstructed video quality of MDC over packet loss networks. For instance, one or more frames after the lost frame in the same stream can be reconstructed using multi-hypothesis decoding, which combines directly decoding and temporally interpolating these frames. Moreover, output obtained from directly decoding and temporally interpolating each frame can be combined by generating a weighted sum of these hypotheses. Constant weights and/or adaptive weights (e.g., determined based on the minimum mean square error criterion) can be used for yielding the weighted sum.

Abstract: Scalable Video Coding is recently attracting attentions due to its high flexibility. The current H.264/AVC scalable extension has adopted the Motion Compensated Temporal Filter (MCTF) framework to provide temporal scalability. In this paper, described is another fast motion estimation (ME) algorithm based on the MCTF framework. Simulation results show that the herein described algorithm can reduce the encoding complexity significantly while maintaining similar bit rate and PSNR, comparing with existing fast ME algorithms implemented in the reference software.

Abstract: Systems and methodologies for concealing frame loss in a video transmission environment are provided herein. Multiple Description Coding (MDC) can be used as an Error Resilience technique for video coding. In case of transmission errors, Error Concealment can be combined with MDC to reconstruct a lost frame, such that the propagated error to following frames can be reduced. Further, multi-hypothesis decoding can be employed to enhance reconstructed video quality of MDC over packet loss networks. For instance, one or more frames after the lost frame in the same stream can be reconstructed using multi-hypothesis decoding, which combines directly decoding and temporally interpolating these frames. Moreover, output obtained from directly decoding and temporally interpolating each frame can be combined by generating a weighted sum of these hypotheses. Constant weights and/or adaptive weights (e.g., determined based on the minimum mean square error criterion) can be used for yielding the weighted sum.

Abstract: We propose methods for generating a halftone image, in which each pixel takes one of two tone values. The generated image contains hidden data, which is present at data storage pixels chosen using a pseudo-random number generator. In a first case, the data is hidden within an existing halftone image by reversing the tone value at certain of the data storage pixels, and at pixels neighbouring the data storage pixels. In a second case, the halftone image is generated from a grey-scale image, and data is hidden during this conversion process.

Abstract: Systems and methodologies for employing bidirectionally decodable Wyner-Ziv video coding (BDWZVC) are described herein. BDWZVC can be used to generate M-frames, which have multiple reference frames at an encoder and can be forward and backward decodable. For example, optimal Lagrangian multipliers for forward and backward motion estimation can be derived and/or utilized. The optimal Lagrangian multiplier for backward motion estimation can be approximately twice as large as the optimal Lagrangian multiplier for forward motion estimation. Further, an optimal P-frame/M-frame selection scheme can be employed to enhance rate-distortion performance when video is transmitted over an error prone channel. Accordingly, a first frame in a group of pictures (GOP) can be encoded as an I-frame, a next m?1 frames can be encoded as P-frames, and a remaining n?m frames can be encoded as M-frames, where n can be a length of the GOP and m can be optimally identified.

Abstract: The claimed subject matter relates to an architecture that can facilitate more efficient free view generation in Ray-Space by way of a Radon transform. The architecture can render virtual views based upon original image data by employing Ray-Space interpolation techniques. In particular, the architecture can apply the Radon transform to a feature epipolar plane image (FEPI) to extract more suitable slope or direction candidates. In addition, the architecture can facilitate improved block-based matching techniques in order to determine an optimal linear interpretation direction.

Abstract: Scalable Video Coding is recently attracting attentions due to its high flexibility. The current H.264/AVC scalable extension has adopted the Motion Compensated Temporal Filter (MCTF) framework to provide temporal scalability. In this paper, described is another fast motion estimation (ME) algorithm based on the MCTF framework. Simulation results show that the herein described algorithm can reduce the encoding complexity significantly while maintaining similar bit rate and PSNR, comparing with existing fast ME algorithms implemented in the reference software.

Abstract: Described herein are various embodiments of a coding technique that utilize a stream cipher for switching between first and second coding conventions for encoding a symbol sequence. The first coding convention specifies a first mapping between a symbol and a first codeword and the second coding convention specified a second mapping between the symbol and a second codeword. According to the invention, a key generated by the stream cipher is used to selected one of the first and second coding convention and the mapping of the selected coding convention is then utilized for encoding the symbol.

Abstract: A method and a computer-readable medium containing computer program for encoding a frame of video data are presented. The frame of video data has a plurality of macro-blocks. Each of the macro-blocks includes a macro-block header having multiple elements and macro-block residue data. An element of the macro-block header is encoded based on the value of the same element of a previous macro-block header so as to reduce overall bits in the macro-block header. The element of the macro-block header is encoded by grouping the elements of the plurality of the macro-blocks.

Abstract: We propose methods for generating a halftone image, in which each pixel takes one of two tone values. The generated image contains hidden data, which is present at data storage pixels chosen using a pseudo-random number generator. In a first case, the data is hidden within an existing halftone image by reversing the tone value at certain of the data storage pixels, and at pixels neighbouring the data storage pixels. In a second case, the halftone image is generated from a grey-scale image, and data is hidden during this conversion process.

Abstract: The claimed subject matter relates to an architecture that can facilitate more efficient free view generation in Ray-Space by way of a Radon transform. The architecture can render virtual views based upon original image data by employing Ray-Space interpolation techniques. In particular, the architecture can apply the Radon transform to a feature epipolar plane image (FEPI) to extract more suitable slope or direction candidates. In addition, the architecture can facilitate improved block-based matching techniques in order to determine an optimal linear interpretation direction.