The picker accepts JPG/JPEG, PNG, WebP, GIF, BMP, TIFF and HEIC image files; typical desktop browsers (Chrome/Firefox) handle uploads up to ~50 MB without problems, though very large TIFF stacks or multi-frame GIFs may be slow. The interface handles one image at a time in the main viewer but you can upload another image anytime; on low-memory mobile browsers you should stay under ~10–20 MB to avoid crashes. If you need batch processing or very large originals, use a desktop browser and reduce resolution to speed sampling.