Abstract: Some examples include receiving a microblog entry from a social stream domain. Further, some implementations include determining, based on a topic space associated with the social stream domain and a media domain, a topic that is associated with the microblog entry. Some implementations include determining, based on the topic space, one or more media items that are associated with the topic.

Abstract: An apparatus comprising a first node configured to communicate with a second node, wherein the first node is configured to receive a first stream from the second node, receive a bridging stream from the second node, and receive the second stream from the second node, and wherein the bridging stream has a lower bit-rate than the second stream. Included is an apparatus comprising at least one processor configured to implement a method comprising transmitting a first stream at a first time, transmitting a bridging stream that has a bit-rate greater than the first stream and less than the second stream at a second time, and transmitting the second stream at a third time.

Abstract: Embodiments of the present invention comprise methods and systems for communicating a recipient-selected customization of a digital image using an index file. The index file associates a customization characteristic with the segments of the digital image required to construct a customized image that exhibits the customization characteristic.

Abstract: An apparatus comprising a first node configured to communicate with a second node, wherein the first node is configured to receive a first stream from the second node, receive a bridging stream from the second node, and receive the second stream from the second node, and wherein the bridging stream has a lower bit-rate than the second stream. Included is an apparatus comprising at least one processor configured to implement a method comprising transmitting a first stream at a first time, transmitting a bridging stream that has a bit-rate greater than the first stream and less than the second stream at a second time, and transmitting the second stream at a third time.

Abstract: A method to remove ringing artifacts from locations near dominant edges of an image reconstructed after compression. The image is decomposed into blocks small enough so that each would contain only one significant edge. A significant edge is tested as to whether it is a dominant edge of the image. If there is no dominant edge, the block is not processed. In the remaining blocks, the exact pixels that include the dominant edges are output without filtering. The direction of the dominant edges is inferred, and then the remaining pixels are filtered with a directional de-ringing filter. The de-ringing filter has a main direction that is perpendicular with the direction of the edge, and thus also with an inherent direction of the ringing artifacts.

Abstract: Embodiments of the present invention comprise methods and systems for communicating a recipient-selected customization of a digital image using an index file. The index file associates a customization characteristic with the segments of the digital image required to construct a customized image that exhibits the customization characteristic.

Abstract: A method and an apparatus for error resilient, digital image scrambling are disclosed. Error resilience scrambling is produced by shuffling transform coefficients between arrays of coefficients arranged along an axis substantially orthogonal to the axis along which packetization of the coefficients proceeds. Scrambling transform coefficients requires a reasonable level of processing resources and has minimal impact on the efficiency of the compression process. Shuffling can be performed in a number of ways to provide good access security and a variety of security. Scrambling the image data in a direction substantially orthogonal to the direction of packetization of the transform coefficients distributes any transmission error in the image reducing the effects of data error or loss on the displayed image.

Abstract: Embodiments of the present invention comprise methods and systems for communicating a recipient-selected customization of a digital image using an index file. The index file associates a customization characteristic with the segments of the digital image required to construct a customized image that exhibits the customization characteristic.

Abstract: A method of post-processing decompressed images includes identification of the direction of an image edge in a pixel block of the image and filtering applied along the boundary of the block in a direction substantially parallel to the detected image edge. Pixels are selected for filtering on the basis of the quantization parameter of the block of which they are members, the relative difference between pixels adjacent to the block boundary, and significant changes value of pixels in a filtering segment. Filtering is applied parallel to the detected edge to protect the sharpness of the edge while reducing or eliminating blocking and ringing artifacts. A method of separately post-processing fields of interlaced video eliminating complications arising from separate compression of the fields is also disclosed.

Abstract: The ability of the visual system to detect contrast in an image is a function of the frequency of the contrasting pattern and the distortion of the image. The visual system is more sensitive to contrasting patterns of lower frequency. When the image is significantly distorted, the visual system is even more sensitive to lower frequencies than higher frequencies. An image encoder employs lossy data compression processes producing a distorted reconstructed image. A method of quantizing image data including the step of varying the magnitude of a quantization step as a function of the distortion of an image is disclosed for further visually optimizing image quantization. Another method utilizes distortion adaptive weighting to vary the limit of code block truncation during embedded bitstream coding to visually optimize image compression by increasing relative lossiness of compression at higher frequencies.

Abstract: The ability of the visual system to detect contrast in an image is a function of the frequency of the contrasting pattern and the distortion of the image. The visual system is more sensitive to contrasting patterns of lower frequency. When the image is significantly distorted, the visual system is even more sensitive to lower frequencies than higher frequencies. An image encoder employs lossy data compression processes producing a distorted reconstructed image. A method of quantizing image data including the step of varying the magnitude of a quantization step as a function of the distortion of an image is disclosed for further visually optimizing image quantization. Another method utilizes distortion adaptive weighting to vary the limit of code block truncation during embedded bitstream coding to visually optimize image compression by increasing relative lossiness of compression at higher frequencies.

Abstract: A method to remove ringing artifacts from locations near dominant edges of an image reconstructed after compression. The image is decomposed into blocks small enough so that each would contain only one significant edge. A significant edge is tested as to whether it is a dominant edge of the image. If there is no dominant edge, the block is not processed. In the remaining blocks, the exact pixels that include the dominant edges are output without filtering. The direction of the dominant edges is inferred, and then the remaining pixels are filtered with a directional de-ringing filter. The de-ringing filter has a main direction that is perpendicular with the direction of the edge, and thus also with an inherent direction of the ringing artifacts.

Abstract: Methods and apparatus for watermarking a digital media object, and for detecting watermarks, are presented. The basic concept underlying the disclosed approach is watermarking/detection in a transform space that allows the same level of watermarking to be applied to all samples. For instance, in one embodiment, a watermarking system first nonlinearly transforms the original signal to a perceptually uniform domain, and then embeds the watermark in this domain without varying the statistical properties of the watermark at each sample. At the watermark detector, a candidate image is transformed to the same perceptually uniform domain, and then correlated with the original watermark sequence. Under such conditions, it is shown that an optimal watermark detector can be derived. This approach is particularly attractive when the original image is unavailable at the detector, as it effectively prevents the image content from biasing the watermark detection score.

Abstract: The ability of the visual system to detect contrast in an image is a function of the frequency of the contrasting pattern and the distortion of the image. The visual system is more sensitive to contrasting patterns of lower frequency. When the image is significantly distorted, the visual system is even more sensitive to lower frequencies than higher frequencies. An image encoder employs lossy data compression processes producing a distorted reconstructed image. A method of quantizing image data including the step of varying the magnitude of a quantization step as a function of the distortion of an image is disclosed for further visually optimizing image quantization. Another method utilizes distortion adaptive weighting to vary the limit of code block truncation during embedded bitstream coding to visually optimize image compression by increasing relative lossiness of compression at higher frequencies.

Abstract: A method to remove ringing artifacts from locations near dominant edges of an image reconstructed after compression. The image is decomposed into blocks small enough so that each would contain only one significant edge. A significant edge is tested as to whether it is a dominant edge of the image. If there is no dominant edge, the block is not processed. In the remaining blocks, the exact pixels that include the dominant edges are output without filtering. The direction of the dominant edges is inferred, and then the remaining pixels are filtered with a directional de-ringing filter. The de-ringing filter has a main direction that is aligned with the direction of the edge, and thus also with an inherent direction of the ringing artifacts.

Abstract: A method for compressing and decompressing image information. An encoder receives initial image information and transforms said initial information using a linear transform to produce coefficients. These are then locally normalized using a neighborhood masking weighting factor, quantized and coded to result in a compressed bit stream. The compressed bit stream is received at a decoder and an inverse process is applied to reconstruct said image data from the compressed bitstream. Alternatively, the neighborhood-masking factor can be applied after quantization in the rate-distortion optimization process.

Abstract: A method embeds tracking data into image graphics data that represents the image according to a first colorspace. The tracking data is embedded during encoding in black or white locations of the image, as variations of the chrominance coefficients. When the resulting data is converted into a second color space, the user tracking data does not alter the eventual visual image. Decoding methods are also provided for extracting the tracking data.

Abstract: An adaptive image coding method and system are disclosed. The system accepts an input image, divides it into image segments, and assigns each segment to a wavelet transform filter from a bank of such filters for transformation. The bank preferably comprises filters adapted for different types of image content, e.g., sharp edges, slowly-varying contours, etc. Filters are preferably assigned so as to produce minimal distortion for their assigned image segments at a given target bit rate, each filter produces transform coefficients for its segment using scale and subband settings common to the entire image. The valid coefficients for each segment are then combined in a composite wavelet coefficient image, which resembles a single wavelet transform of an entire image—although different filters are used to create different portions of the coefficient image. The composite image allows joint, rate-distortion optimized coding for a segmented image.

Abstract: A method for re-indexing a palette-indexed image is disclosed. The method uses an array of symbol cross-counts that indicate the degree of occurrence, within the image, of symbols in one or more predefined contextual relationships, such as symbol adjacency. One objective of the method is to manipulate the palette index such that adjacent symbols in the image are assigned indices that are as close as possible in symbol space, thus enhancing the subsequent compressability of the image with many lossless compressors. As global minimization is generally computationally impracticable, the disclosed embodiments present a greedy suboptimal solution to this problem. The basic method uses a one-dimensional reassignment pool and a seed symbol. A single symbol is selected for positioning either to the immediate right or left of the seed in the pool, according to a potential function that uses the cross-count array.

Abstract: Methods and apparatus for encryption and decryption of digital images are disclosed. A preferred embodiment operates on an image frame after that frame has undergone a space-frequency transform operation, such as a block DCT or wavelet transform, and before the frame is passed to a bitstream coder for entropy coding. The transform coefficient map is subjected to one or more encryption operations that render a subsequently decoded (but not decrypted) image incomprehensible. These operations are designed to operate with low computational overhead and with only minor effects on compressed bit rate. They also allow secure transcoding at intermediate routers of the transmission channels without the cryptographic key. In one operation, the sign bits of transform coefficients are scrambled. In another operation, two dimensional blocks of coefficients from a common subband are shuffled and/or rotated to pseudorandom locations and orientations.