Patent ID: 7602850

Claim:
A method for decoding a bitstream comprising: using a variable length coding (VLC) decoder to perform operations of generating an indication of a number of coefficients and a number of trailing ones in a portion of a bitstream using either: a first lookup table (LUT) indexed by a number of leading zeros to return a number that indicates a number of remaining bits in a code to be read from the bitstream and a second LUT indexed by both the number of leading zeros and the remaining code bits to return the number of coefficients and the number of trailing ones; or bit level parsing when the leading zeros value equals a predetermined value; generating an indication of a number of total zeros, including using either a third LUT indexed by the number of coefficients and bits of the bitstream when the number of coefficients is in a first range or bit level parsing when the number of coefficients is outside the first range; generating an indication of one or more run before values using either a fourth LUT indexed by the number of coefficients and bits of the bitstream when a zeros left value is in a second range or bit level parsing when the zeros left is not in the second range; and generating coefficients in block positions in response to the generation of the trailing ones value, the number of coefficients value, the total zeros value and run before values.