in a block 123 similarly a reference time number may be calculated indicative of how much time elapsed between the first maximum sample and the first sample this reference delta number may then be companded to provide a companded delta reference number and a max reference value may then be determined by adding the companded reference delta number to said min reference value as indicated in the calculation block 113 a new min reference value may thereafter be determined by subtracting the first companded delta number as determined in the calculation block 109 from the max reference value as also indicated in the calculation block 109 and then replacing the previously determined min reference value with the new min reference value similarly after the second delta number has been calculated a new max reference value can be determined by adding the second companded delta number to the min reference value and replacing the previously determined max reference value with the new max reference value all as indicated in the calculation block 113 following the flow chart of fig1 a 1b and 1c in sequence the compression routine begins with a calculation block 125 comprising three steps the first step 34 store type equal compress 34 stores a value indicative of the compression type to distinguish the type of segment from some other type which may be selected as will be more particularly discussed in a subsequent paragraph the second step of the block 125 34 let total equal one 34 sets a counter designated as 34 total 34 equal to one representing the first sample the third step of the block 125 34 store value of first sample 34 indicates that the value of the first of stream of samples is to be stored the block 125 leads to the.