MPEG is a primary standards for dynamic image compression. The error can be introduced in the quantization process of the block DCT transformation . In this sense, the shape compensation by Boolean filter is proposed by us to adjust the intensity distribution of the motion compensated image. That is, our dynamic images are coded by the kinds of Boolean filter in addition to motion vectors after DCT coding. Boolean operation is usually applied to the binary images. The minterms of Boolean operations can be reprensented by masks. For the gray level images the mask operation is changed to be the more complex window operations. More clearly, there are two masks for a miniterm. One is a complement mask. The other is a maximum or minium window. For coding efficiency, in this paper a common complemented mask is used for two miniterms. In this sense, our Boolean filters are limited in a category of two miniterms with a same complemented structure. Experiment results have demonstrated that images going through the extra Boolean filtering have better visual quality than images processed by motion compensation only. The price is paid by the coding complexity and a relatively simple decoding structure. However, it is the decoding process which is more crucial in real time play. Therefore, we successfully integrated the Boolean filtering into MPEG-1 system in software implementation.