Motion picture expert group (MPEG) video coder/decoder apparatus

A motion picture expert group (MPEG) video coder-decoder (CODEC), comprising:

• a coding/decoding mode generator for detecting whether a mode signal inputted from an input terminal is a coding-mode, or a decoding-mode, and generating one among first to ninth mode control signals according to a detected mode;
• a coder/decoder selector for selectively converting a routine of a coded bit stream according to said first to ninth mode control signals which are generated from said coding/decoding mode generator;
• and
• an MPEG video coder/decoder for selectively coding or decoding an image bit stream selected by the coder/decoder selector, and then transmitting the image bit stream to a storage element, or to a displayer,
• wherein said coder/decoder selector comprises:
• a second multiplexer which not only selects a variable length coded bit row from a variable length coder according to a fourth mode control signal generated from said coding/decoding mode generator and then outputs said variable length coded bit row to a first output terminal through a first buffer, but also selects a bit row to be decoded and then provides said bit row to a variable length decoder through said first buffer;
• a first multiplexer which selects both a discrete cosine transform (DCT) coefficient information which is decoded by said variable length decoder, and a pair of run and level which is zigzag scanned by a zigzag (ZZ) scanner according to a third mode control signal, and then provides both said DCT coefficient information and said pair of run and level to an inverse ZZ scanner;
• a third switching part which outputs an image information in which a motion is compensated by an adder, to an output terminal of a decoder through a second frame reconstructing part, according to a fifth mode control signal generated from said coding/decoding mode generator;
• a third multiplexer which selects both a coding-type of said variable length coder and a decoding-type of said variable length decoder, and then transmits both said coding-type and said decoding-type to a sixth switching part, according to a sixth mode control signal generated from said coding/decoding mode generator;
• a fourth multiplexer which selects an inter/intra signal achieved from an inter/intra analyzer according to a seventh mode control signal generated from said coding/decoding mode generator, or another inter/intra signal reproduced by said variable length decoder, and controls a fifth switching part;
• a fifth multiplexer which selects a motion vector achieved from a motion estimating part, or another motion vector reconstructed by said variable length decoder, and then provides a selected motion vector to a motion compensator, according to an eighth mode control signal generated from said coding/decoding mode generator;
• a fourth switching part which selects a reference image data of a forward-estimation reference image memory, or another reference image data of a reverse-estimation reference image memory, and then provides a selected reference image data to said motion estimating part, according to a ninth mode control signal generated from said coding/decoding mode generator;
• a second switching part which is switched by a second mode control signal generated from said coding/decoding mode generator, and then provides a motion-compensated image information through said fifth switching part to a subtractor;
• and
• a first switching part which provides an input image information generated from a first frame reconstructing part to the motion-estimation part, according to a first mode control signal generated from said coding/decoding mode generator.