What quality are the extracted images?

Original embedded quality — JPEGs come out byte-for-byte as stored, other bitmaps convert to PNG. No screenshots, no recompression.

Why were some images skipped?

Vector graphics aren't image files, and rare encodings (fax/JBIG2) can't be converted — the tool extracts what's genuinely extractable.

No — extraction runs in your browser.

Pull every embedded photo and graphic out of a PDF exactly as stored — no screenshots, no recompression, zipped for download. Private.