2007.04.02 12:12 "[Tiff] EXIF JPEG Thumbnail in TIFF", by Phil Harvey

2007.04.02 15:24 "Re: [Tiff] EXIF JPEG Thumbnail in TIFF", by Phil Harvey

Thanks Joris,

Your comments are useful. At least it is now clear that libtiff can't be used to process these thumbnails. So at the very least, it means that you can't use libtiff to process EXIF information in JPEG images, which is unfortunate.

I re-read the EXIF specification. It does clearly state that compressed JPEG thumbnails are not allowed if the primary image is uncompressed (section 4.5.5 of the EXIF 2.2 specification, page 12), which could rule out a majority of TIFF images, but as far as I can see they should be allowed in compressed TIFF images.

Either my understanding of the EXIF specification is wrong, or maybe it is just that this technique just never caught on.

- Phil