Subband DCT coding of HDTV signal in intraframe under a bit rate of 140 Mbits/s
Yan Chang, Chang Chuntian · 2002
A subband coding scheme based on the DCT of the intraframe is demonstrated, which compresses the bit rate of an HDTV signal from about 1.2 Gbits/s to less than 140 Mbits/s. The HDTV signal is split up into four subbands by a separable 2D quadrature mirror filter bank (QMF). The DCT transform and quantization, considering the property of human vision are applied to the baseband. The other high bands are quantized by a quantizer with a center deadzone. To further reduce the information bit rates, variable length coding (VLC) and run-length coding (RLC) are applied to the quantized signal in each band. The buffer adaptive control on the bit rate of subbands makes the data steam in the channel uniform. Computer simulation results are presented in terms of the bit-per-pel and SNR of the reconstructed pictures. The objective and subjective quality of the reconstructed pictures are excellent.>