Do you see anything that looks like a file allocation table? It's been a long time since I cared much about dos filesystem details.
On Sun, Jan 12, 2020 at 3:57 PM Russell Senior <[email protected]> wrote: > Step 1 is to dd the whole USB drive to a backup image. Then from a copy of > that backup image you can start trying recovery from that. > > On Sun, Jan 12, 2020 at 1:32 PM Keith Lofstrom <[email protected]> wrote: > >> The three book scanners near the checkout desk at the >> PSU Millar library are somewhat difficult to use, but >> better than my slow USB flatbed scanner at home. >> >> Yesterday I scanned three huge multipage files to a >> Brand X "Cheap on Amazon" 2GB USB flash drive. I was >> in a hurry, so I did not segment the files into smaller >> chunks, or check the files with my laptop as I made them. >> >> Bad idea. >> >> I now have a flash drive which is 60% full, but no files >> are listed in the directory. Either the files were too >> large for the scanner, or the 40 character file names were. >> The flash drive is formatted for VFAT16 DOS or somesuch. >> >> I hope to recover the files (if not the file names) and >> avoid another 90 minute, 200+ page scanning marathon. >> I can grep the drive image for strings; I don't see the >> filenames, but grep shows about 100 strings like >> /ProcSet [ /PDF /ImageB ] -or-f /ProcSet [ /PDF /ImageC ] >> and some fragments. I tried using "testdisk" tools to >> recover the three files; no joy. >> >> My best guess is that my overly-long scan files blew >> the memory buffer on the PSU scanner, and it overwrote >> garbage. There are signs above the scanners to "save >> frequently" which I ignored (https://www.xkcd.com/293/) >> >> PERHAPS SOMEONE CAN SUGGEST CLEVER TOOLS to extract the >> pdfs from the 1.2 gigabytes of "unlabeled something" on >> the flash drive. Knowing how might help me help others >> in the future. >> >> I expect I will only get my files by scanning them >> again, properly, in small chunks PSU's feeble scanners >> can handle. Meanwhile, "don't do that" is probably the >> most help I can offer to others. >> >> Keith >> >> P.S. - the best book scanner I've used was at MIT Barker >> Library; it images the book open 120 degrees, face up, >> and accomodates the natural curve of the pages. The book >> scanners in the Library of Congress are almost as good, >> but you must stretch the pages flat to get focused images. >> >> -- >> Keith Lofstrom [email protected] >> _______________________________________________ >> PLUG mailing list >> [email protected] >> http://lists.pdxlinux.org/mailman/listinfo/plug >> > _______________________________________________ PLUG mailing list [email protected] http://lists.pdxlinux.org/mailman/listinfo/plug
