Because yellow-yellow is the most common block, we want that to be substituted for the most compact representation.

因为黄-黄色是最常见的块，所以我们希望用它来代替最紧凑的表示。

Let's take a look at another type of lossless compression, where blocks of data are replaced by more compact representations.

让我们看一下另一种无损压缩，其中数据块被更紧凑的表示形式所取代。

The two approaches we discussed, removing redundancies and using more compact representations, are often combined, and underlie almost all lossless compressed file formats, like GIF, PNG, PDF and ZIP files.

我们讨论的这两种方法， 即删除冗余和使用更紧凑的表示， 通常结合使用，并且构成几乎所有无损压缩文件格式的基础， 如 GIF、PNG、PDF 和 ZIP 文件。