How to convert scanned pictures to a pdf book

I have scanned in 300 pages of pictures and want to "bind" it as a pdf book. I tried some ways, but I could not make it with so many pages. I am looking for a way, where all pages named as A00001, A00002 ...... in one directory would be converted into one pdf file. Hereby, it should always add one page and not open all pages at once. Which program, script do you suggest for that? bye Ronald Wiplinger