Abstract: Sequential digital video frames are divided into two interleaved fields comprising even-numbered horizontal lines of pixels and odd-numbered lines horizontal lines of pixels respectively. The "even" field of a first standard frame is combined with the "odd" field of a second standard frame to form a first pseudo-interlaced frame of data for display; then the same odd field is combined with the even field of a third standard frame to form a second pseudo-interlaced frame of data for display, and so on throughout a continuing digital-video message. The data transmission rate needed is thus reduced by nearly a factor of two, or conversely, for a given data rate, nearly twice as much video information can be transmitted in the same time interval.

Abstract: Two or more run-val mapping tables are selected to encode different subsets of video signals of a sequence of video signals. Each run-val mapping table is selected to map a particular set of run-val pairs to a corresponding set of run-val codes. Each run-val pair comprises a run and a val, the run corresponding to a length of a run of video signals having value zero and the val corresponding to a video signal having a non-zero value. Each run-val mapping table is used to generate a different part of an encoded bitstream for the sequence of video signals. The encoded bitstream is then decoded using the two or more selected run-val mapping tables. In a preferred embodiment, the selected run-val mapping tables are explicitly identified in the bitstream.

Abstract: Video signals are encoded and decoded using a set of quantization tables that is generated from a base matrix and a scale matrix, which are both explicitly encoded into the encoded video bitstream. The sets of quantization tables may be changed as often as needed as long as the new base and scale matrices are explicitly encoding into the bitstream.

Abstract: Video signals are encoded using motion compensation based on motion vectors generated using multi-phase motion estimation. In a first phase, a first subset of video signals of each block is compared to the reference frame at locations corresponding to a first set of motion vectors. In a second phase, a second subset of video signals of each block is compared to the reference frame at locations corresponding to a second set of motion vectors, where the resolution of the first subset of video signals in the spatial domain is lower than the resolution of the second subset of video signals. In an alternative embodiment, in the first phase, each block is compared to the reference frame at locations corresponding to a first set of motion vectors. In the second phase, each block is compared to the reference frame at locations corresponding to a second set of motion vectors, where the second set of motion vectors is based on at least two best matches from the first phase.

Abstract: A heterogeneous multimedia stream has interleaved samples of two or more different substream types. For example, a heterogeneous video stream may have interleaved intra, predicted, and bi-directional frames. In addition to a global bit bank, a different bit bank is maintained for each different frame type. A global quantization level is selected for each frame based on the global bit bank and the bit bank for the corresponding frame type. The frames are encoded using the selected global quantization levels. In a preferred embodiment, the number of bits available for encoding frames differs based on the frame type. In addition, any unused bits from encoding the current frame are shifted from the bit bank corresponding to the current frame type to a bit bank of a different frame type.

Abstract: The video encoding scheme used by a video encoder is selected from a variety of different possible video encoding schemes having different decode rates to generate an encoded video bitstream to achieve a desired decode rate in a specified decoding environment. The video encoder allows a user to select different characteristics of the video encoding scheme to generate the encoded video bitstream for a specific decoding platform.

Abstract: Video signals are run-length encoded using a scan pattern and encoded video signals are run-length decoded using the scan pattern, where the scan pattern is explicitly encoded into the encoded bitstream. In a preferred embodiment, the scan pattern is generated by applying a constrained sorting rule to energy measures corresponding to the video signals to be encoded. The scan pattern used for encoding can be changed as often as needed where each new scan pattern is explicitly encoded into the bitstream for use in decoding.

Abstract: A video system is disclosed that provides fast communication packet loss recovery. A source node generates a series of encoded video flames for a series of digitally sampled video flames by encoding each digitally sampled video frame relative to either an immediately preceding digitally sampled video frame or a previous digitally sampled video frame specified by a lost frame message received over the communication link from a destination node. The destination node receives the encoded video frames over the communication link and transfers the lost frame message to the source node if one of the encoded video frames is lost or delayed. The destination node generates the decoded version of each encoded video frame relative to either a decoded version of an immediately preceding encoded video frame or a decoded version of a last successfully received encoded video frame.

Abstract: An encoded bitstream is generated for playback scalability in terms of both bitrate scalability and decode scalability. During encoding, at least one component plane of each video frame is transformed into two or more bands of data. Each band is then encoded independent of the other bands and the resulting encoded bands are embedded in an encoded bitstream. At least one band sequence is encoded using interframe encoding.

Abstract: For decoding, a first portion of an encoded bitstream is decoded to generate a first decoded video frame. A second portion of the encoded bitstream is decoded to generate a second decoded video frame. A temporal filter is applied to the first decoded video frame and the second decoded video frame to generate a filtered second video frame. For encoding, a first unencoded video frame is encoded to generate a first encoded video frame. The first encoded video frame is decoded to generate a first decoded video frame. A second unencoded video frame is encoded to generate a second encoded video frame. The second encoded video frame is decoded to generate a second decoded video frame. A temporal filter is applied to the first decoded video frame and the second decoded video frame to generate a filtered second video frame. A third unencoded video frame is encoded to generate a third encoded video frame.

Abstract: A quantization level is selected for the current video frame in accordance with a plurality of mappings, wherein each mapping correlates an activity measure with a bits per frame measure and each mapping corresponds to a quantization level of a plurality of quantization levels. The current video frame is encoded in accordance with the selected quantization level.

Abstract: A scan path is generated using one or more two-dimensional sets of training signals. For encoding, a two-dimensional set of signals is encoded using the scan path. For decoding, a two-dimensional set of encoded signals is decoded using the scan path. In a preferred embodiment, a plurality of different scan paths are generated for a plurality of quantization levels; signals are transformed and quantized using selected quantization levels; and the quantized, transformed signals are encoded using the scan paths corresponding to the selected quantization levels.

Abstract: Reference frames are generated by applying spatial filtering to decoded video frames after pixel reconstruction. For encoding video signals, the reference frames are used to encode subsequent video frames using interframe encoding. For decoding video signals, the reference frames are used to decode subsequent video frames using interframe decoding. In a preferred embodiment, motion estimation and motion compensation form part of the interframe encoding and decoding procedures.

Abstract: A compressed bitstream signal corresponding to an image is decompressed to generate a decompressed image signal and the decompressed image signal is displayed. For each of a plurality of interframe quantization levels, there is a corresponding intraframe quantization level and a corresponding energy measure threshold value. The correspondence between the interframe quantization levels, on the one hand, and the intraframe quantization levels and energy measure threshold values, on the other, is determined using one or more training video frames. For encoding, blocks of video frames are either interframe encoded or intraframe encoded as selected based on a selected interframe quantization level and the corresponding energy measure threshold value. For decoding, blocks of encoded video frames are either interframe decoded or intraframe decoded as selected based on a selected interframe quantization level and the corresponding energy measure threshold value.

Abstract: Reference frames are generated by selectively filtering blocks of decoded video frames. The decision whether to filter a block is based on a comparison of an energy measure value generated for the block and an energy measure threshold value corresponding to the quantization level used to encode the block. The energy measure threshold value for a given quantization level is selected by analyzing the results of encoding and decoding training video frames using that quantization level. The reference frames are used in encoding and decoding video frames using interframe processing.