针对上海数字电视图像质量较差的问题，对播出系统中几个环节进行图像质量的客观测量，通过对测量数据的分析，发现编码器的编码带宽对图像质量影响较大。为此，在对目前的播出系统进行讨论的基础上，提出一种加大编码器的编码率，从而提高数字电视图像质量的方法。

To deal with the problem that Shanghai digital TV picture quality is poorer than traditional cable TV, picture qualities of several broadcasting taches are messured objectively. Lots of testing data are analyzed, and a conclusion is drawn that the encoding bandwith of encoders have great influnce on picture quality. Therefore, on the basis of current broadcasting system, a new method for increasing the encoding bandwith of encoders is discussed and put forward to improve the digital television picture quality.