2005.01.20 23:41 "Re: [Tiff] JPEG (T.30-E, fax) in TIFF", by Lee Howard

On about line 634 of libtiff/tif_jpeg.c (3.7.1 release) it says:

        sp->photometric = td->td_photometric;
        switch (sp->photometric) {
        case PHOTOMETRIC_YCBCR:
                sp->h_sampling = td->td_ycbcrsubsampling[0];
                sp->v_sampling = td->td_ycbcrsubsampling[1];
                break;
        default:
                /* TIFF 6.0 forbids subsampling of all other color spaces */
                sp->h_sampling = 1;
                sp->v_sampling = 1;
                break;
        }

Is that true? It seems to contradict what we've discussed in this thread. Does the TIFF spec really forbid subsampling of all color spaces other than YCBCR photometric?

Lee.