System.FileAccess.CDirectoryIterator System.FileAccess.openDirectory("./", "rw"); It.setFilterExpression("*.png"); while (It.notEnd()) { CString Src = It.getName(); CString Dst = Src.copy(); System.RegEx.replace(Dst, "$png", "jpg", System.RegEx.SingleOccurency); System.ImageLibrary.CImage Img; Img.loadPNG(Src); Img.saveJPG(Dst, System.ImageLibrary.Overwrite); It.advance(); }