Patent ID: 8135071

Claim:
A method comprising: (a) determining a breakpoint for hybrid variable length coding an ordered sequence of quantized transform coefficients of a block, or for hybrid variable length coding ordered sequences of a multi-block partition, the breakpoint determining using a relationship to properties of blocks that neighbor the block or multi-block partition, wherein the quantized transform coefficients have respective amplitudes of a set of amplitudes including a most likely-to-occur amplitude, wherein the hybrid variable length coding an ordered sequence of quantized transform coefficients of a block includes recognizing any event that includes a cluster of one or more consecutive quantized coefficients having amplitude other than the most likely-to-occur amplitude, encoding a first part of the sequence using a selected low-frequency coding method, the selected low-frequency coding method including recognizing an ending event, the encoding a first part being up to and including the recognized ending event, and encoding a second part of the sequence starting from immediately after the recognized ending event using a selected high-frequency coding method, wherein the breakpoint indicates the location of the ending event in the sequence; (b) encoding the ordered sequence of quantized transform coefficients of the block, or the ordered sequences of the multi-block partition, using the hybrid variable length coding and the recognized ending event; and (c) in the case information additional to the properties of the neighboring blocks would be needed by a decoder or decoding process to determine the breakpoint determined in (a), encoding sufficient information about the relationship such that a decoder or decoding process can, prior to decoding the coded data of the block or multi-block partition use the sufficient information and the properties of the neighboring blocks to determine the breakpoint used to encode the coded data of the block or multi-block partition, such that the breakpoint may be variable among blocks of an image, wherein the properties and the neighboring blocks are such that in the decoding, the properties of the neighboring blocks are known or determinable prior to the decoding of the coded data of the block or multi-block partition.