On 8/25/07, Andy Green <andy@xxxxxxxxxxx> wrote: > >>> Is there any way of converting a bunch of pdf files to pnm without > >>> loosing resolution? > >> What happens when you use the -dpi= option on pstopnm? > > > > OK, Andy, but how can one find out the dpi's of our pdf file? > > Well the pdf is not normally already rasterized in the case of text, so > for that there is no "dpi of our pdf file". It will render the text > nicely according to the dpi you asked for. > > If there are raster images (at various dpi) in the pdf then it will > scale them to the dpi you asked for AIUI. So I guess you should pick a > dpi that is close to the highest image dpi in the pdfs (eg, 300) and run > with it. Thanks, Andy. In fact, the pdf file that I have got contains a scanned document. Is there some way of determining the dpi used in the scanning work? Paul
