Abstract: The present invention provides a method of encoding and transmitting a block of visual data within a visual data stream. First, image information updates are acquired for the block of visual data that includes pixel data and is associated with a change history of pixel data. Next, stored block information is retrieved for the block of visual data, including a recent change history for the block of visual data. Next, a determination is made from the retrieved block information and the image information updates that the block of visual data is a video image type. Available network bandwidth is then determined. Encoding parameters for the block of visual data from the retrieved block information, the image information updates and the available network bandwidth are determined. The block of visual data is encoded and transmitted across a computer network.

Abstract: The present invention provides a method of progressively encoding and transmitting visual data. First image information updates are acquired for a region of visual data. The region of visual data is defined by a plurality of blocks of pixel data, and individual blocks of the plurality are associated with individual change histories for their respective pixel data. Stored region information including a recent encoded state for each block in the plurality is retrieved. Available network bandwidth is determined, and then encoding parameters for each block in the region of visual data are determined from the retrieved region information and the available network bandwidth. The plurality of blocks is then encoded, the retrieved region information is updated in accordance with the determined encoding parameters; and the encoded blocks are transmitted across a computer network.

Abstract: A method of transforming and sending data, comprising: receiving an image with an associated mask; transforming the received image; quantizing the transformed image; encoding the quantized image and associated mask; and transmitting the encoded image and mask; wherein transforming the received image comprises transforming the dimension subset by repeating steps of: preparing an input vector; determining a filter type; determining a first intermediate vector; determining a second intermediate vector; computing a transform vector from the sum of the first intermediate vector and the second intermediate vector; and computing an output value from the input vector and the computed transform vector.

Abstract: The invention provides a non-intrusive method and apparatus for encoding a digitized raster display signal which may then be transmitted from a host computer system to a remote display across a communications link. Hash codes are used to detect persistent blocks of pixels in a real-time digital raster signal generated by the host computer. A progressive encoding and transmission sequence is then initiated, using parameters such as bandwidth availability and build quality requirements to determine suitable encoding methods and build levels.