1994.01.25 10:59 "Re: Adobe Private TIFF Tag", by Niles Ritter
Does anyone know what tag 34377 is? I've encountered it in TIFF files built by Adobe Photoshop, but even though it's a private tag, Adobe says they don't know what it is and referred me to Aldus.
I just created an RGB TIFF file from scratch, using Adobe Photoshop, and running tiffdump on it I got:
SubFileType (254) LONG (4)
1<0>
ImageWidth (256) SHORT (3)
1<0>
ImageLength (257) SHORT (3)
1<0>
BitsPerSample (258) SHORT
(3) 3<8 8 8>
Compression (259) SHORT (3)
1<0>
Photometric (262) SHORT (3) 1<0>
StripOffsets (273) LONG (4)
1<604>
SamplesPerPixel
(277) SHORT (3) 1<0>
RowsPerStrip (278) SHORT (3)
1<0>
StripByteCounts
(279) LONG (4) 1<196608>
XResolution (282) RATIONAL (5)
1<72>
YResolution (283) RATIONAL (5)
1<72>
PlanarConfig
(284) SHORT (3) 1<0>
ResolutionUnit (296)
SHORT (3) 1<0>
34377 (0x8649) BYTE (1)
388<56 66 73 77 3 233 0 0 0 0 0 120 0 3 0 0 0 72 0 72 0
0 0 0 2 218 2 40 255 225 255 226 2 249 2 70 3 71 5
40 3 252 0 2 0 0 0 72 0 72 0 0 0 0 2 218 2 40 0 1
0 0 0 100 0 0 0 1 0 1 1 1 0 0 0 1 39 15 0 1 0 1 0
0 0 0 0 0 0 0 0 0 0 0 0 2 0 25 1 144 0 0 0 0 0 64 0
0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
56 66 73 77 3 237 0 0 0 0 0 16 0 72 0 0 0 1 0 1 0
72 0 0 0 1 0 1 56 66 73 77 3 243 0 0 0 0 0 7 0 0 0
0 0 0 0 0 56 66 73 77 3 245 0 0 0 0 0 72 0 47 102
102 0 1 0 108 102 102 0 6 0 0 0 0 0 0 0 47 102 102
0 1 0 161 153 154 0 6 0 0 0 0 0 0 0 50 0 0 0 1 0 90
0 0 0 6 0 0 0 0 0 0 0 53 0 0 0 1 0 45 0 0 0 6 0 0 0
0 0 0 56 66 73 77 3 248 0 0 0 0 0 112 0 0
255 255 255 255 255 255 255 255 255 255 255 255 255
255 255 255 255 255 255 255 255 255 3 232 0 0 0 0 255
255 255 255 255 255 255 255 255 255 255 255 255 255 255
255 255 255 255 255 255 255 3 232 0 0 0 0 255 255 255 255
255 255 255 255 255 255 255 255 255 255 255 255 255 255
255 255 255 255 3 232 0 0 0 0 255 255 255 255 255 255 255
255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 3 232 0 0>
Some parts look like resolution values (72 0 72 0), and other parts look like lookup tables or perhaps small bitmaps for a mask. In either case, since this file was created by Adobe, somebody over there *should* know what the thing is for. Looks like a private structure of some sort. Ask to talk to one of their technical guys, not the artists.
BTW, every color TIFF image I created was given the same tag and value; changing the "preferences" of the program, changing the saturation/ levels/brightness/pagesetup/size etc. of the image made no difference. The only time I got a different count/value of that tag was when I converted the color tiff to grayscale. An interesting pattern occurs if you organize the last run of 255's by rows of 28 bytes each:
0 0 255 255 255 255 255 255 ... 255 255 255 255 255 3 232 0 0
0 0 255 255 255 255 255 255 ... 255 255 255 255 255 3 232 0 0
0 0 255 255 255 255 255 255 ... 255 255 255 255 255 3 232 0 0
0 0 255 255 255 255 255 255 ... 255 255 255 255 255 3 232 0 0
I have no idea what that means; I'm not that good a numerologist:-)
-niles.