Sequence and merge jpeg images using Python?

im doing a project as part of academic programme.Im doing this in linux platform.here i wanted to create a application which retrieve some information 开发者_开发问答from some pdf files .for eg i have pdfs of subject2,subject1,in both the whole pdf is divided in to 4 modules and i want to get the data of module 1 from pdf..for this purpose my tutor told me to use pdftohtml application and convert pdf files to html and jpeg images.now i want to create a Python script which will combine the pages(which have been coverted in to jpeg images) under module 1 and merge it into a single file and then i will convert it back to pdf . how can i do this?.if anyone can provide any such python script which have done any functions similar to this then it will be very helpful.

.... thanks in advance

Not exactly knowing what you mean my sequence - ImageMagick, esp. its 'montage' is probably the tool you need. IM has python interface, too, altough I have never used it. EDIT: As after your edit I do not get the point of this any more, I cannot recommend anything, either. :(