Two different jobs, often confused
Extract images pulls the rasters already sitting inside the PDF: the JPEG the layout tool embedded, the PNG of a logo, the scan you placed. Resolution is whatever is in the file. No drum, no upscale.
PDF to JPG (or PNG) photographs the whole page: type, rules, empty paper, crop marks if you left them. Use that when you need a picture of the spread, not the assets inside it.
Your volume, your plates
This table is for files you made or are licensed to reuse. A downloaded magazine PDF is not a moodboard kit. Pdfmira will run the job; the right to the pictures does not come with the button.
After extraction, the plates are often huge and unnamed. Compress or convert to WebP only if they will live on a site. For a new impose, keep the heaviest original you recovered.
When extraction comes back empty
Vector type and drawings are not images. A page built from paths will yield nothing on this table. Rasterise the page instead. The same is true of some PDFs that paint pixels without a classic XObject image — you will get a picture of the page, not a folder of stills.
If you only need pages 4–6 of a catalogue, extract the page range first, then pull images from the short PDF. Less noise, less weight on the free sheet.