Abstract: A method, system and computer software product for improving rate-distortion performance while remaining faithful to JPEG/MPEG syntax, involving joint optimization of Huffman tables, quantization step sizes and quantized coefficients of a JPEG/MPEG encoder. This involves finding the optimal coefficient indices in the form of (run, size) pairs. By employing an interative process including this search for optimal coefficient indices, joint improvement of run-length coding, Huffman coding and quantization table selection may be achieved. Additionally, the compression of quantized DC coefficients may also be improved using a trellis-structure.

Abstract: Methods for custom processing of HTTPS data transmitted between a web browser and a web server are described. The methods comprise creating a custom request header by intercepting and modifying a HTTPS header. The modification indicates support for preselected customized processing operations. The method further comprises sending the custom request header with a HTTP request to a web server. The methods further comprise receiving processed payload data from the web server and a HTTP response header. The processed payload data is created by processing original payload data based on preselected customized processing operations. The web browser modifies the response header to create a modified response header, and the processed payload data using one or more of the customized processing operations. The modified payload data is provided to the web browser for use. The methods ensure that the web browser implements and executes the underlying channel set up and encryption operations.

Abstract: A method and system for reducing the number of mathematical operations required in the JPEG decoding process without substantially impacting the quality of the image displayed is disclosed. Embodiments provide an efficient JPEG decoding process for the purposes of displaying an image on a display smaller than the source image, for example, the screen of a handheld device. According to one aspect of the invention, this is accomplished by reducing the amount of processing required for dequantization and inverse DCT (IDCT) by effectively reducing the size of the image in the quantized, DCT domain prior to dequantization and IDCT. This can be done, for example, by discarding unnecessary DCT index rows and columns prior to dequantization and IDCT. In one embodiment, columns from the right, and rows from the bottom are discarded such that only the top left portion of the block of quantized, and DCT coefficients are processed.

Abstract: A method of determining, at a mobile device, side information including compression state information. The method includes receiving, from a server, a unique side information identifier identifying a unit of side information used by the server for compressing data, determining, based on the side information identifier, if the unit of side information is resident on said device, and if the unit of side information is resident on the mobile device, loading the side information for decompressing the data. Otherwise, if the unit of side information is not resident on the mobile device, the method includes requesting the unit of side information from one of the server and another device.

Abstract: A method, system and computer software product for improving rate-distortion performance while remaining faithful to JPEG/MPEG syntax, involving joint optimization of Huffman tables, quantization step sizes and quantized coefficients of a JPEG/MPEG encoder. This involves finding the optimal coefficient indices in the form of (run, size) pairs. By employing an interactive process including this search for optimal coefficient indices, joint improvement of run-length coding, Huffman coding and quantization table selection may be achieved. Additionally, the compression of quantized DC coefficients may also be improved using a trellis-structure.

Abstract: The present invention relates to the compression of color image data. A combination of hard decision pixel mapping and soft decision pixel mapping is used to jointly address both quantization distortion and compression rate while maintaining low computational complexity and compatibility with standard decoders, such as, for example, the GIF/PNG decoder.

Abstract: A method and system for arbitrary resizing of a compressed image in the discrete cosine transform (DCT) domain. First and second scaling parameters P and Q are determined in accordance with the block numbers L and M and the scaling ratio L/M or M/L. A non-uniform, or uneven, sampling in the DCT domain is then applied to coefficients of successive blocks in the compressed image in accordance with the scaling parameters. In an embodiment, P blocks are sampled and transformed from a given block length to |P| according to a |P|-point IDCT, while Q blocks are sampled and transformed from a given block length to |Q| according to a |Q|-point IDCT. The non-uniformly sampled and transformed pixel domain samples are then regrouped into a predetermined block size and transformed back to generate the DCT coefficient of the compressed image. The proposed method significantly reduces the computational complexity compared with other DCT domain arbitrary ratio image resizing approach.

Abstract: For context based compression techniques, for example Context Based YK compression, a method and system for grouping contexts from a given context model together to create a new context model that has fewer contexts, but retains acceptable compression gains compared to the context model with more contexts is provided. According to an exemplary embodiment a set of files that are correlated to the file to be compressed (hereafter called training files) are read to determine, for an initial context model, the empirical statistics of contexts and symbols. In some embodiments, this includes determining the estimated joint and conditional probabilities of the various contexts and symbols (or blocks of symbols). The initial context model is then reduced to a desired number of contexts, for example, by applying a grouping function g to the original set of contexts to obtain a new and smaller set of contexts.

Abstract: The invention is directed at a method of managing side information, used during interactive compression, common to a server and one of multiple devices. In order to manage common side information, a global common side information table including entries for the side information is maintained. The entries store characteristics of the common side information and include a reserve counter whereby entries can be reserved so that they are not erroneously deleted from the server.

Abstract: The present disclosure relates to methods and systems for progressively delivering multimedia content over a network. According to one aspect, a system for delivering multimedia content through a network includes a server side sub-system and a client side sub-system. The server side sub-system is configured to: concurrently send a first predetermined portion of each of the plurality of objects through the network, wherein the first predetermined portion is less than a complete object for at least one of the plurality of objects; and after sending the first predetermined portion of each of the plurality of objects, successively send subsequent predetermined portions of each of the plurality of objects until all portions of the plurality of objects have been sent.

Abstract: The invention described here deals with implementing custom data processing of HTTPS based on a Browser-Plugin Method. Stich custom data processing may include, but is not limited to, custom data compression, custom data encryption, data monitoring, data modification. There are two distinct methods to implement the Browser-Plugin Method for Advanced HTTPS Data Processing of the subject invention (BPAHDP). In both cases, BPAHDP provides the option of conducting custom data processing that co-exists with data compression, data encryption, or other types of data processing operations supported by the HTTP standard. Additionally, both BPAHDP methods ensure that the web-browser still implements and executes the underlying SSL/TLS channel setup and encryption operations. In both embodiments of BPAHDP, the most critical functionality is the ability to modify HTTP request/response headers and data sent over a TLS/SSL channel. In the regular. HTTP case (HTTP over TCP) headers and data are sent as clear-text (i.e.

Abstract: A system and method for caching data and verifying cached data using a client-server model and meta-data. In particular, a client proxy and a server proxy are in communication with each other and with the client and the server, respectively; client proxy meta-data and server proxy meta-data related to the data cached by the client proxy and server proxy, respectively, are calculated and communicated between the client proxy and the server proxy; and the client proxy meta-data and the server proxy meta-data are compared to determine a cache hit or miss.

Abstract: A method of lossless data compression is provided which uses a grammar transform to sequentially construct a sequence of greedy context-dependent grammars from which an original data sequence can be recovered incrementally. The data sequence is encoded using any one of a sequential context-dependent method, an improved sequential context-dependent method, and a hierarchical context-dependent method.