Microprocessor dedicated to processing of bit streams in a system of compression/decompression of animated images

A microprocessor including an operator dedicated to an extraction of variable-length codes from a sequence of contiguous codes, the operator being associated with a dedicated instruction using a parameter which indicates a length of a group of bits to be extracted, the operator responding to the instruction by extracting from an active register a number of bits indicated by the parameter, starting from an end of a group of bits which has been extracted from the active register by a preceding execution of the dedicated instruction.

A microprocessing method including the steps of;

• providing an operator dedicated to a concatenation of variable-length codes to form a sequence of contiguous codes, the operator being associated with a dedicated instruction using two parameters, a first one of which is a word containing a group of bits and the second one of which indicates a length of the group of bits, the operator responding to the dedicated instruction by;
• isolating, in the first parameter, the group of bits having the length indicated by the second parameter and by;
• inserting the bit group so isolated into an active register, in concatenation with a bit group which has been inserted in the active register by a previous execution of the dedicated instruction.

A microprocessing method comprising the steps of;

• providing an operator dedicated to an extraction of variable-length codes from a sequence of contiguous codes, the operator being associated with a dedicated instruction using a parameter which indicates the length of a group of bits to be extracted, the operator responding to the instruction by extracting from an active register the number of bits indicated by the parameter, starting from the end of a group of bits which has been extracted from the active register by a preceding execution of the dedicated instruction.