tiff2pdf returns Not a TIFF or MDI file I can view the tiff, yet conversion fails: $ tiff2pdf input.tiff -o foo.pdf returns input.tiff: Not a TIFF or MDI file, bad magic number 13392 (0x3450). tiff2pdf: Can't open input file input.tiff for reading. . $ file input.tiff returns input.tiff: Netpbm image data, size = 5008 x 6981, rawbits, bitmap

Your file's extension is a lie, and you indeed do not have a TIFF image. You've got a NetPBM image, which can be converted to TIFF using `pamtotiff` or `pnmtotiff` from the NetPBM library (or any of several other image convertors).