2000.01.29 16:12 "Re: tiff2ps: G4 compression in PostScript]", by Paul Kaiser

Surely the most important property is that the results are identical *after* expansion. I don't remember whether the ITU specifies the encoder in such a way that there is exactly one legal encoding of a given image. In fact, I suspect it does not.

Yes, you're right as I look at it closer. There are three methods an encoder can choose from when encoding, and it can switch at any time (though it will indicate this switch in the data.) Also, as you say, it can choose to compress or not

I know that I have put together my PostScript code correctly, and I have tried G4 compressed images from as many sources as I can get (a whole "2"). Yet it still isn't working.

I suspect that a PostScript interpreter has specific restrictions, then. I just ordered the "Green Book" on PostScript programming, so I'll see in a few days. I have all of the other PostScript books, all of the recent PostScript and PDF stuff of the Adobe site -- none of it sheds light on any of it. I hope the green book says "it has to be this-a-way" so we can get on with this.

Take care,

Paul Kaiser