Data compression technique of downhole video image
Jiatian Zhang · Journal of Xi'an Shiyou University · 2007
The bandwidth for the data transmission of logging cable is very limited,so image compression is the key technology to the development of a downhole video.A down-hole video image compression system based on wavelet transform is developed.It accomplishes the compression of video images by wavelet transform,subband coding,adaptive quantization and entropy coding,and it achieves to a very high compress ratio.The DSP technology and special image compression IC used in the system makes the compression ratio and data stream easy to be controlled.The down-hole video image compression system is suitable to the data transmission single-core cable,multi-core cable,or photoelectric logging cable.A field insertion technology is used in the decompression and playback of the video image,and the real-time playing speed of 50 fields per second of PAL system video is realized.