while (toFilePth length () & gt; The config. The SIZE) {
Thumbnails of (toFilePth). Scale (1 f). OutputQuality (0.6 f) outputFormat (" JPG "). ToFile (toFilePth); 
} 

As above, use Thumbnails library circulation compressed images, loop smaller file Size, for the first time, but after a second file Size no change, excuse me, may be what causes this? How to solve?