AWARE SYSTEMS
TIFF and LibTiff Mail List Archive

Thread

1996.11.14 17:05 "Single TIFF read/write", by Magdy Halim
1996.11.14 19:05 "Single TIFF read/write", by Frank Kim
1996.11.14 21:06 "Re: Single TIFF read/write", by Magdy Halim

1996.11.14 19:05 "Single TIFF read/write", by Frank Kim

I was wondering if you know of a way to read and write to the same tiff file. I tried the "r+" mode but i had to close and open the file every time i change a scanline, besides it doesn't like compression (even when the rowsperstrip field is 1).

The reason being that i have a 1.6 Gbyte image and opening a new one is practically impossible.

All i wanna do is change some pixels inside the image.

According to the HTML documentation (tiff-v3.4/html/libtiff.html#FIO):

      Note that unlike the stdio library TIFF image files may not be
opened for both reading and writing; there is no support for altering
the contents of a TIFF file.

I tried doing both a read and write in some programs. Sometimes it worked but other times I got seg faults. I'd have to say it sounds like a bad idea.

Frank Kim       NetCentric Corporation
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