PNG, JPG, etc. store EXIF metadata as a binary blob which can be parsed by libexif. TIFF has EXIF as a subdirectory of the image:

$ tiffinfo 2698060_kicsi.tif
=== TIFF directory 0 ===
TIFF Directory at offset 0x8 (8)
  Subfile Type: (0 = 0x0)
  Image Width: 450 Image Length: 600
  Resolution: 150, 150 pixels/inch
  Bits/Sample: 8
  Compression Scheme: LZW
  Photometric Interpretation: RGB color
  Orientation: row 0 top, col 0 lhs
  Samples/Pixel: 3
  Rows/Strip: 194
  Planar Configuration: single image plane
  Software: Adobe Photoshop 21.1 (Windows)
  DateTime: 2020:09:06 01:06:32
  XMLPacket (XMP Metadata):
  RichTIFFIPTC Data: <present>, 7 bytes
  Photoshop Data: <present>, 6728 bytes
  EXIFIFDOffset: 0xb4324
  ICC Profile: <present>, 560 bytes
  Predictor: horizontal differencing 2 (0x2)
--- EXIF directory within directory 0 
TIFF Directory at offset 0xb4324 (738084)
  ColorSpace: 65535
  PixelXDimension: 450
  PixelYDimension: 600

But not always! Sometimes it's inside the XMP. libvips supports XMP metadata, but just reading and writing it would not be enough, you'd need to parse it and detect any embedded EXIF as well, then reformat the XML as an EXIF blob. And you'd need to pull out any EXIF TIFF subdirectory and send that to libexif, which would need some work with the insides of libtiff.

Anyway, it's painful to support and not very widely used, so the motivation has not been there, so far. A PR would be very welcome, of course.

Uh oh!

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