AWARE SYSTEMS
TIFF and LibTiff Mail List Archive

Thread

2007.09.23 16:42 "[Tiff] G3 fax: EOL needed at the beginning of each strip?", by ComSquare Martin Osieka
2007.09.24 01:27 "Re: [Tiff] G3 fax: EOL needed at the beginning of each strip?", by Bob Friesenhahn
2007.09.24 05:56 "Re: [Tiff] G3 fax: EOL needed at the beginning of each strip?", by Joris
2007.09.24 07:24 "Re: [Tiff] G3 fax: EOL needed at the beginning of each strip?", by ComSquare Martin Osieka
2007.09.24 07:51 "Re: [Tiff] G3 fax: EOL needed at the beginning of each strip?", by Joris
2007.09.24 08:01 "Re: [Tiff] G3 fax: EOL needed at the beginning of each strip?", by Andy Cave
2007.09.24 08:32 "Re: [Tiff] G3 fax: EOL needed at the beginning of each strip?", by Joris
2007.09.24 08:45 "Re: [Tiff] G3 fax: EOL needed at the beginning of each strip?", by Andy Cave
2007.09.24 09:03 "Re: [Tiff] G3 fax: EOL needed at the beginning of each strip?", by Joris
2007.09.24 08:52 "Re: [Tiff] G3 fax: EOL needed at the beginning of each strip?", by ComSquare Martin Osieka
2007.09.24 08:58 "Re: [Tiff] G3 fax: EOL needed at the beginning of each strip?", by Andy Cave

2007.09.24 08:58 "Re: [Tiff] G3 fax: EOL needed at the beginning of each strip?", by Andy Cave

Well there you have the specifics. Section 10 is for CCITT Huffman, so I would say that Huffman's can (should) not contain EOLs, but G3/G4s should.

----- Original Message -----

Cc: "Joris" <joris.at.lebbeke@skynet.be>; <tiff@lists.maptools.org> Sent: Monday, September 24, 2007 9:52 AM Subject: Re: [Tiff] G3 fax: EOL needed at the beginning of each strip?

I'm curious - where in the spec does it indicate strips have to start with

You may interpret this from TIFF 6.0 section 11 "CCITT Bilevel Encoding"

Strips and Tiles.

When CCITT bi-level encoding is employed, interaction with

stripping (Section 3) and tiling (Section 15) is as follows:

a. Decompose the image into segments-individual pixel arrays representing

        the desired strip or tile configuration. The CCITT encoding
procedures are
        applied most flexibly if the segments each have a multiple of 4
lines.
    b. Individually encode each segment according to the specified CCITT
bilevel
        encoding, as if each segment is a separate raster-graphic image.

Means strips should be encoded independent from each other.
I do not have access to the CCITT spec in the moment, but I guess they are
telling an image must start with EOL.

Still section 10 tells no EOLs needed...
So I would expect T.4 TIFFs containing no EOLs at all are legal.