2004.12.09 10:12 "Re: [Tiff] Q: writing tiled TIFFs", by Joris Van Damme

if i have a tile size of 256x256 and a 200x200 image, how should i fill the tile buffer before calling TIFFWriteTile? LibTiff doesn't give me any errors when i go to write it, so i assume it's a legal tile size. but, the image pixels are messed up (looks like row length is wrong somewhere).

Are you properly padding stuff, so as to end up with 256 lines of 256 pixels? If not, you ought to.

However, I wouldn't write such a TIFF as tiled, even though you can. If you consider 256x256 good tile sizes, then the following is not necessary, but it is 'smart' tiff writing with all benefits of tiled storage where they are real benefits, and never much padding compared to image size:

if image width and image height are both <= 256 then
  write as single strip, strip height equal to image height
else if image width <= 256 then
  write as strip TIFF, strip height 256
else if image height <= 256 then
  write as tile TIFF, tile size 256 x image height
else
  write as tile TIFF, tile size 256 x 256

Joris Van Damme
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