基于小波变换的零树数字摄影图像编码方法

The Encoding Method of Null-tree Digital Photographic Image on a Foundation of Wavelet Transformation

图像数据压缩编码是数字摄影测量领域的关键环节之一。本文介绍了小波零树编码的原理，提出了一种基于正交小波零树的编码方案：首先对图像进行四级小波变换，然后对第四级小波分解的低频分量进行无损压缩，舍去第一级小波分解的对角线方向高频分量，对其余子图先采用零树量化编码，再游程编码。实验表明，该方法是一种比较有效的方法。

The compressed encoding of image data is one of the most important ring - joint of digital photogrammetric surveying field. The principle of wavelet null - tree encoding is introduced, an encoding scheme is proposed basing on orthogonal null-tree of wavelet. First the image is processed for 4 order wavelet transform,then the lows of the fourth order of wavelet is compressed loselessly,the highs of the diagonal of the first order is caste out,the other is encoded using null- tree first,then using tour encoding. The test proves that the method is a effective one.