MPEG-2传输编解码器的DSP虚拟应用

MPEG-2 Transcoder Virtual Application on DSP Media Processor

MPEG-2视频编码广泛用于广播视频和HDTV。由于存储器和传输能力的限制,实际应用中,必须降低MPEG-2视频码流的比特率。因此,我们提出一种在DSP上实时实现的频域传输编解码技术(FDTC)。FDTC对存储器和复杂性要求较低,同时,低时延的码率控制技术提供了系统恒定比特率(CBR)的码流输出并且比级联的大容量MPEG-2视频编解码器具有更好的峰值信噪比(PSNR)。

Mpeg-2 video coding is widely used in broadcasting and HDTV. For the limitation of storage and/or transmission capacity, it may be necessary to reduce the bit rate of MPEG-2 video bit-streams. Accordingly an real-time implementation of a frequency domain transcoder(FDTC) on DSP media processor is proposed. FDTC has such advantages as low demand for storage and less complex system. Together with low delay bit-rate control technique, this proposed technique can provide Constant Bit-Rate (CBR) output and better Peak Signal-to-Noise Rate (PSNR) compared with bulky cascade of a complete MPEG-2 video decoder and encoder.