In view of some drawbacks in gray associative analysis method, this paper presents a linear interpolation method, which considerably improves the resolution.

The paper investigate a structure of the digital down-converter(DDC) and put forward a design of numerical controlled oscillator with method of tabulation view and fraction ratio decimation filter with mixing linear interpolation algorithm and CIC filter,so that the DDC process could be implemented in software on general purpose DSP chip and afford greater flexibility.

In the context, qualified visual three-dimensional ICT pictures are achieved through multi-piece two-dimensional images accumulation by, combining with thresholding method and linear interpolation.

Section nonlinear interpolation algorithm analysis of new electro-optic transformer;

Having analysed the localization of several typical methods for traveltime computation(finite difference method,linear interpolation method and so on) in briefly,authors put forward a method for traveltime computation based on nonlinear interpolation,and deduced its calculation formula.

Regarding the inherent drawbacks of linear interpolation (edge blurring or artifact), nonlinear interpolation technique is studied in this paper.

The application of one-dimension non-linear interpolation inreconstruction of ultrasound B mode images;

The traditional non-linear interpolation based on travel-time square although improved the computational precision of ray path and travel time, the algorithm is not suitable for the area the velocity violently changed.