Patent ID: 7907071

Claim:
A data conversion apparatus, which converts encoded data that is Packbit-encoded to have a set of length information and data information as a unit code, into new Packbit-encoded data, which is expressed by length information indicating the number of output data not more than M output data smaller than the maximum number of output data after decoding that can be expressed by one length information of Packbit-encoded data, and data information, the apparatus comprising: an input unit which inputs encoded data to be converted; a separation unit which separates the input encoded data into length information and data information; a buffer which stores length information; a count unit which receives the length information obtained by the separation unit as length information of interest, and obtains cumulated result by cumulatively counts the number of output data after decoding indicated by the received length information, where, if significant length information is stored in the buffer, the count unit does not receive the length information obtained by the separation unit but acquires the length information stores in the buffer as length information of interest; a length information division unit which inputs the length information of interest, and performs one of the following processes (a)-(c): (a) outputs the received length information of interest when the cumulated result is smaller than M, (b) outputs length information of interest when the cumulated result is M, outputs delimiter information indicating that the value reaches M, and resetting the cumulated result, and (c) divides the length information of interest into first length information indicating a difference between M and a counted value until length information immediately before the length information of interest, and second length information indicating the remaining number of output data when the cumulated result is larger than M, outputs the first length information, outputs delimiter information indicating that the value reaches M, and stores the second length information significant length information for the next counting by the count unit in the buffer; a length information generating unit which receives the length information outputted from the length information division unit, and generates, when a plurality of pieces of length information each indicating that data information is output once successively appear in the pieces of already received length information every time the delimiter information is input, new one length information from these pieces of successive length information; and a data combining unit which refers to the length information obtained via the length information generating unit, combines the length information and the data information separated by the separation unit, and outputs the combined information as new Packbit-encoded data.