图像放大技术的关键在于使放大后的图像尽可能地保持原始图像的清晰度。对于红外图像而言，传统的内插法存在着一定的缺陷。提出了一种基于小波变换的图像放大新算法，该算法对原始图像先进行小波变换获得高频系数，然后运用牛顿插值算法放大高频系数，以此作为放大图像的高频成份，而将原始图像作为低频成份，最后进行小波逆变换，重构出放大图像。实验证明该方法在图像细节方面具有很好的放大效果。

The key of image magnification technique is to ensure that the definition is as good as the initial image. For an infrared image, traditional interpolation algorithms have their faults. A new image magnification algorithm based on wavelet transform is proposed. The high-frequency coefficients obtained from the initial image by wavelet transform are enlarged through Newton interpolation, which are used to be high-frequency components of the magnification image, while the initial image is used to be the low-frequency component of the magnification image. Then, the magnification image is reconstructed by wavelet inverse transform. The test demonstrates that the algorithm has a good effect on the image detail.