java - Write result image using jmagick -

i want crop part of image , write result image file. code looks this

imageinfo imageinfo = new imageinfo("file path"); magickimage image = new magickimage(imageinfo );  rectangle cropinfo = new rectangle(); cropinfo.x = 20; cropinfo.y = 20; cropinfo.width = 300; cropinfo.height = 300;  magickimage result = image.cropimage(cropinfo);  result.setfilename("path result file"); boolean s = result.writeimage(imageinfo); 

the above code works why writeimage using old imageinfo? , magickimage.setfilename don't make sense me. think should create new imageinfo object , write imageinfo. following code make more sense don't work expected.

magickimage result = image.cropimage(cropinfo); imageinfo resulinfo = new imageinfo("path new file"); boolean s = result.writeimage(imageinfo); 

does experience ?

it inconvenient me keep original imageinfo around, tried , worked:

result.setfilename("path result file"); boolean s = result.writeimage(new imageinfo()); 

as why parameter needed @ all, mystery remains. null not work.