- 2007.01.31 16:56 "Re: [Tiff] 16bit grayscale with colormap", by Toby Thain
- 2007.01.31 17:01 "Re: [Tiff] 16bit grayscale with colormap", by Bob Friesenhahn
- 2007.01.31 17:31 "Re: [Tiff] 16bit grayscale with colormap", by Joris Van Damme
- 2007.01.31 17:53 "Re: [Tiff] 16bit grayscale with colormap", by Bob Friesenhahn
2007.01.31 17:53 "Re: [Tiff] 16bit grayscale with colormap", by Bob Friesenhahn
On Wed, 31 Jan 2007, Reinhard Mayr aka Czerwinski wrote:
> Bob,
>
> thanks for that quick response! Attached there is the mentioned sample file I created with a hex editor. (The colormap contains just crap data but should be enough for a proof of concept.) The opening behavior of some programs was described in my initial post.
>
> How can you display the file?
No, I can not. In fact libtiff's tiffinfo does not like the file
either (libtiff fails to locate the colormap) so it seems that the
file is not formulated correctly:
% tiffinfo CytoScout16bitImageJ-0106_3-v5.tif
CytoScout16bitImageJ-0106_3-v5.tif: Error fetching data for field "ColorMap".
MissingRequired: CytoScout16bitImageJ-0106_3-v5.tif: TIFF directory is missing required "Colormap" field.
% tiffdump CytoScout16bitImageJ-0106_3-v5.tif
CytoScout16bitImageJ-0106_3-v5.tif:
Magic: 0x4d4d <big-endian> Version: 0x2a
Directory 0: offset 8 (0x8) next 0 (0)
SubFileType (254) LONG (4)
1<0>
ImageWidth (256) SHORT (3)
1<200>
ImageLength (257) SHORT (3)
1<200>
BitsPerSample (258) SHORT
(3) 1<16>
Photometric (262) SHORT (3) 1<3>
ImageDescription (270) ASCII (2) 34<ImageJ=1.37v\nmin=57.0\nma ...>
StripOffsets (273) LONG (4)
1<768>
SamplesPerPixel
(277) SHORT (3) 1<1>
RowsPerStrip (278) SHORT (3)
1<200>
StripByteCounts
(279) LONG (4) 1<80000>
Colormap (320) SHORT (3) 196608<12337
12851 13365 13879 14393 16706
17220 17734 12337 12851 13365 13879 14393 16706 17220 17734 12337
12851 13365 13879 14393 16706 17220 17734 ...>
The error reported by libtiff when used by GraphicsMagick is that it
fails to retrieve the colormap:
Error fetching data for field "ColorMap".
Bob
======================================
Bob Friesenhahn
bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer, http://www.GraphicsMagick.org/