Extracting images from pdf

Hy,
I have a pdf file,where every page is an image.I'm having trouble saving these images on-by-one to my hard disk. I tried getting the id of the img, selecting by id then saving it, averythin looks great, return values are OK, but  the saved picture is black page.Can you help me Please?

I use FindImages to make sure program detects the pictures, it gives me the correct number(for example this will be x).I use getimageID to get the id of pictures numbered 1 to x.(it seemes that it could get the id of the pictures, it's a quite long number as i rembeber).when i get an ID i use SelectImag, the return value is 1 indicating it's correct.Then i call ImageType, which tells me it's a bmp, which i would like to use in the future so it's perfect.Then comes SaveImagetoFile.It returns 1 , so it should be okay, but it's still just a black page. Here's my code for better understanding(altough it's a bit messy):
 MentMappa = "C:\\";
 for (int i = 0; i < konyvtar.QuickPDFPageCount(ID); i++)//every page consists of 1 picture,FindImages gives me the number of the images which is equal to the pagenukber so it's correct
                {
                    int kepszam = konyvtar.QuickPDFFindImages(ID);
                    Kepetment = MentMappa + "tmpkep"+(i + 1) + ".bmp";
                    int imgid = konyvtar.QuickPDFGetImageID(ID, i + 1);
                    int kepv = konyvtar.QuickPDFSelectImage(ID, imgid);
                    int keptipus = konyvtar.QuickPDFImageType(ID);
                    int sikeresmentes=konyvtar.QuickPDFSaveImageToFile(ID, Kepetment);
                   //Esetleg a képbol kivagom amegfelol reszt
                    BeKep = new Bitmap(Kepetment);
                   // and so on ...
}

Is there a way to convert a pdf to a bmp ? If so, how?
What is the diffrence between saving an img in the pdf to file if i put it there in the program, or i loaded the pdf and the picture was included?
Thanks for help!
edit:i don't really need it to save on the disk, but i have to use it in a Bitmap format, maybe it's possible to create a Bitmap variable from the selected image in the document?


Edited by Hbaloo - 29 Apr 09 at 12:57PM