Patent ID: 6233280
Filing Date: 2001-05-15
Classification: H04N

Abstract:
A video decoder for high definition television comprising:a variable length decoder decoding codes corresponding to discrete cosine transform (DCT) coefficients of an applied video bit stream, and producing a run-level pair for each code;an index decoder storing run-level pairs produced from the variable length decoder, and producing the position information indicating the number of a level value of a corresponding run-level pair among the DCT coefficients;an inverse quantizer obtaining an added value corresponding to the position information of the index decoder from a quantization matrix, and performing an inverse quantization for the DCT coefficients by multiplying a quantizer level for determining a quantization step and a corresponding DCT coefficient to the added value;an inverse scanner including a plurality of memories, and inversely scanning the DCT coefficients inversely quantized and received serially from the inverse quantizer, wherein the inverse scanner produces the DCT coefficients in parallel at the same time, and wherein the inverse scanner comprises,first and second buffers storing the DCT coefficients inversely quantized,a coefficient buffer controller generating a write/read address and a write/read enable signal to the first and second buffers, anda multiplexer selectively producing parallel output data received from the first and second buffers being the parallel DCT coefficients; andan inverse discrete cosine transformer performing an inverse discrete cosine transformation (IDCT) of the DCT coefficients received in parallel from the inverse scanner.