ADPCM for advanced LANDSAT downlink applications

Under funding from the Defense LANDSAT Program Office, a method was developed for compressing multispectral data. A rate-controlled adaptive differential pulse code modulation technique was developed with minimal complexity for downlink applications. This algorithm uses an adaptive 2-D and 3-D prediction of pixels. The difference between the predicted and original pixel is quantized with a locally adaptive quantizer. This technique has produced compression ratios of up to 2.5:1 losslessly and up to 5:1 with minimal visual image quality loss on LANDSAT and M-7 high resolution multispectral data. This paper describes the ADPCM algorithm and its impact on numerical, visual and machine exploitation performance.<>