2006.04.11 10:12 "Re: [Tiff] LibTiff Suggestion, Need help to support application supplied JPEGTables.", by Joris Van Damme

Gerben,

Meanwhile, why are you refering to a pseudo tag? Would it not suit these needs, if the actual JpegTables tag can be set, and when next LibJpeg is used to compress, in this case, the application supplied tables that are set in this tag are used?

Yes, that could also be an idea. But I suppose you will either have to a) parse the tables out from the tag yourself, or b) create a temporary libjpeg decompression object to do that parsing, and then copy the tables into the libjpeg compression object. Neither seems very elegant to me.

But I'm not going to implement this, and I'm not very much into the libtiff internals when it comes to JPEG compression, so your ideas are probably worth more than mine.

I think there may be a better solution, but I'm not sure... I'm not even completely sure what current state of tif_jpeg is in this regard.

I'll look into it shortly, and report back to the list.

Joris Van Damme
info@awaresystems.be
http://www.awaresystems.be/
Download your free TIFF tag viewer for windows here:
http://www.awaresystems.be/imaging/tiff/astifftagviewer.html