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TIFF and LibTiff Mail List Archive

2008.06.24 07:27 "[Tiff] Extracting raw data from tiff files with different number of rows/strip", by Bogdan Cristea

Can someone explain or point some references for the procedure used to write into TIFF files multiple strips?

I try to extract from two TIFF files raw data in order to transmit data using a fax/modem, but the number of bytes is different when extracting data from TIFF files with different number of rows/strip, even if the image in both files is identical.

Below it is listed the output of tiffdump for the two TIFF files I use. The second file (with multiple strips) was obtained from the first one (single strip) using tiffcp utility in order to change only the number of rows/strip.

Magic: 0x4949 <little-endian> Version: 0x2a <ClassicTIFF>
Directory 0: offset 866 (0x362) next 0 (0)
ImageWidth (256) SHORT (3) 1<1728>
ImageLength (257) SHORT (3) 1<2241>
BitsPerSample (258) SHORT (3) 1<1>
Compression (259) SHORT (3) 1<4>
Photometric (262) SHORT (3) 1<0>
FillOrder (266) SHORT (3) 1<2>
StripOffsets (273) LONG (4) 1<8>
Orientation (274) SHORT (3) 1<1>
SamplesPerPixel (277) SHORT (3) 1<1>
RowsPerStrip (278) LONG (4) 1<4294967295>
StripByteCounts (279) LONG (4) 1<858>
XResolution (282) RATIONAL (5) 1<204>
YResolution (283) RATIONAL (5) 1<196>
PlanarConfig (284) SHORT (3) 1<1>
Group4Options (293) LONG (4) 1<0>
ResolutionUnit (296) SHORT (3) 1<2>
PageNumber (297) SHORT (3) 2<0 1>
Software (305) ASCII (2) 9<fax2tiff\0>

Magic: 0x4949 <little-endian> Version: 0x2a <ClassicTIFF>
Directory 0: offset 15692 (0x3d4c) next 0 (0)
ImageWidth (256) SHORT (3) 1<1728>
ImageLength (257) SHORT (3) 1<2241>
BitsPerSample (258) SHORT (3) 1<1>
Compression (259) SHORT (3) 1<4>
Photometric (262) SHORT (3) 1<0>
FillOrder (266) SHORT (3) 1<2>
StripOffsets (273) LONG (4) 2241<8 15 22 29 36 43 50 57 64 71 78 85 92 99 106
113 120 127 134 141 148 155 162 169 ...>
Orientation (274) SHORT (3) 1<1>
SamplesPerPixel (277) SHORT (3) 1<1>
RowsPerStrip (278) SHORT (3) 1<1>
StripByteCounts (279) LONG (4) 2241<7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7
7 7 7 ...>
XResolution (282) RATIONAL (5) 1<204>
YResolution (283) RATIONAL (5) 1<196>
PlanarConfig (284) SHORT (3) 1<1>
Group4Options (293) LONG (4) 1<0>
ResolutionUnit (296) SHORT (3) 1<2>
PageNumber (297) SHORT (3) 2<0 1>
Software (305) ASCII (2) 9<fax2tiff\0>

--
Bogdan Cristea