Abstract: A coder/decoder selects one of a set of look-up tables for encoding/decoding a symbol. Each look-up table contains boundary values that result from an arithmetic coding model partitioning a first interval. A second interval contains an arithmetic code. During encoding, look-up table entries for a symbol value are converted to the scale of the second interval. The scaled values indicate a smaller interval containing the arithmetic code. Code bits are generated when most significant bits of upper and lower scaled values are equal. During decoding, a code word, which is a part of an arithmetic code, is normalized from the scale of the second interval to the scale for a look-up table and then compared to entries of the look-up table. When a segment containing the code word is identified, a decoded symbol value is known. A scaling circuit converts boundary values for the segment to the scale of the second interval then changes the second interval.