However, there are easier ways to extract those images, for example, the one purposed by PDF Image Extractor.
PDF Image Extractor is the free application for Windows that will allow you to extract and save all those images you always wanted to have.
The process is extremely easy, run PDF Image extractor, choose the PDF file containing the picture and PDF Image extractor will detect it and will list the pictures in the document. Then you'll only have to select the ones you want to save.
Finally you'll be able to choose the format and quality of the output pictures.