| 摘要 |
A bidirectional discrete cosine transform (DCT) coefficient scanning apparatus includes a buffer memory, an address generator based on a look-up table for converting a first address signal to a second address signal according to a DCT coefficient scan order, a first selection section for selecting the second address signal or a third address signal as the address signal for the buffer memory, and a second selection section for selecting a quantized DCT coefficient or a decoded DCT coefficient to be written to the buffer memory during coding or decoding. During coding, quantized DCT coefficients from a quantization section are written to locations in the buffer memory identified by the third address signal, and read out to a run-length and level coding section from locations in the buffer memory identified by the second address signal. During decoding, decoded DCT coefficients from a run-length and level decoding section are written to locations in the buffer memory identified by the second address signal, and read out to a dequantization section from locations in the buffer memory identified by the third address signal. |
