AWARE SYSTEMS
TIFF and LibTiff Mail List Archive

Thread

1999.02.02 15:30 "Basic question regarding PackBits...", by Takao Matsuda
1999.02.02 15:32 "Re: Basic question regarding PackBits...", by Helge Blischke
1999.02.02 17:00 "Re: Basic question regarding PackBits...", by Ed Grissom
1999.02.02 17:07 "Re: Basic question regarding PackBits...", by Helge Blischke

1999.02.02 17:00 "Re: Basic question regarding PackBits...", by Ed Grissom

Takao, Helge,

Here is the relevant section from the TIFF 6.0 spec. Note that the runs DO break at the end of a line. You do NOT compress across lines as if the strip is one homogenous buffer. [...] [...] Here are some additional rules:

. Pack each row separately. Do not compress across row boundaries.

[...] When PackBits data is decompressed, the result should be interpreted as per compression type 1 (no compression).


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