1997.02.12 03:56 "TIFF 6.0 JPEG or OJPEG_SUPPORT", by Ali Ozer

You could try decompressing them on a NeXT... They should load OK.

BTW, you should note that there are two "old jpeg TIFF" formats on the NeXT; one is real old, using all sorts of tags obsoleted in 6.0, and one is based on the early drafts of 6.0. Here are the tags:

The "real old":

Directory at 0x19bfa
  Image Width: 530 Image Length: 799
  Tile Width: 544 Tile Length: 800
  Resolution: 144, 144
  Resolution Unit: pixels/inch
  Bits/Sample: 8
  Compression Scheme: NeXTstep 2.0 JPEG encoding (32865)
  Photometric Interpretation: RGB color
  JPEG Processing Mode: 0 (0x0)
  JPEG Restart Interval: (no restart markers)
  Samples/Pixel: 3
  Number of Tiles: 1
  Planar Configuration: Not planar

The early 6.0:

Directory at 0x1a940
  Image Width: 530 Image Length: 799
  Tile Width: 544 Tile Length: 256
  Resolution: 144, 144
  Resolution Unit: pixels/inch
  Bits/Sample: 8
  Compression Scheme: JPEG encoding (6)
  Photometric Interpretation: RGB color
  YCbCr Subsampling: 2, 2
  YCbCr Coefficients: 0.299, 0.587, 0.114
  JPEG Processing Mode: baseline sequential algorithm
  JPEG Quantization Tables: (present)
  JPEG DC Tables: (present)
  JPEG AC Tables: (present)
  Samples/Pixel: 3
  Number of Tiles: 4
  Planar Configuration: Not planar
  Reference Black/White: 16, 235, 128, 240, 128, 240

I can't come up with more details without much research...

Ali