AWARE SYSTEMS
TIFF and LibTiff Mail List Archive

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2001.10.01 11:20 "", by Cecilia Rodrigues
2001.10.01 12:59 "Re:", by Joris Van Damme

2001.10.01 12:59 "Re:", by Joris Van Damme

I need to specificy the offset i.e offset of where exactly the data will start.so is there any method to calculate the stripbyteoffset?????

StripByteOffset is supposed to point to your strips. So, their values will depend on how exactly you want to append this IFD.

One way would be to
  - append the strips first (note that you KNOW where you write them)
  - append the IFD with known strips byte offsets

If you want to write the IFD first, you'll need to take a look at the rest of your writing code to figure out where the strips are going to end up (or fill in these values at a later time or something).

Same goes for *any* tag data requiring more than 32bits. Either you already appended the data to the file by the time you append the IFD, and you know where it is, or either you'll have to examine your writing code in order to come up with a good method to determine where it's going to end up (or fill in these values at a later time or something).

Note that this 'appending' sceme does not include true 'memory managment'. Eg, if you add a page to a tiff file from which pages have been 'deleted' at some time, 'appending' means that you do not attempt at recovering that space.

Joris