Hi Dave, Only a few very specific image widths are correct for FAXing. The good image you attached is 1728 pixels wide. This is the correct width for most FAXes. The bad image is 2901 pixels wide, which is not one of the acceptable widths for a FAX.
So, that explains why some images work and some don't. The sending side should, however, report the page width problem. I will take a look at the code to see why that didn't happen. Regards, Steve Dave Thomson wrote: > I've encountered an issue with faxing (T.38) certain G3 encoded tiff > files wherein the sending system reports that the fax was successfully > sent while the receiving system aborts quite early on in the process > with "Received a DCN while waiting for a DIS". My setup is such that > I have two identical Linux systems running callweaver-1.2.0.1 and > spandsp-0.0.5pre4 that are connected to the same T.38 proxy and I am > sending faxes between them using TxFAX and RxFAX. I have done a lot > of testing and can confirm the following: > > 1. With the right tiff files, I can successfully fax in both > directions. > 2. Both TxFAX and RxFAX are set up for ecm. > 3. When I generate a problem tiff file, the problem is the same > regardless of direction (the sender always reports the fax > successfully sent; the receiver reports failure). > 4. Both the good and bad tiff files are generated using: > > convert inputfile.jpg /options /pdf:intermediate.pdf > gs -q -sDEVICE=tiffg3 -sPAPERSIZE=letter -r204x196 -dNOPAUSE > -sOutputFile=outputfile.tif -- intermediate.pdf > > 4. convert is an ImageMagick (6.4.4) image manipulation application. > 5. I can consistently generate good or bad files based on how I set > up the /options/ above. As long as the phrase -page letter > appears in the right place, the file can be faxed. > 6. convert can also be used to generate a tiff file directly but I > have been unable to get any of these files to fax using many > different methods including: > 1. Generating convert's default tiff file output (uncompressed > color) and used tiff2bw, tiffdither, and tiffcp -c g3:fill > to create a g3 tiff file. > 2. Using convert's -compress fax option (with many different > modifiers) to create a g3 tiff file. > 3. Taking the output of the above and using tiffcp to combine a > good fax file with a bad one to create a new one. In this > case, the file gets sent but, using windows fax viewer, the > good portion displays fine but the bad portion is rendered > as garbage. > 7. Looking at the udptl traffic, the receiver aborts very early on in > the conversation between 30 and 100 packets. > 8. The sip traffic looks the same regardless of whether the fax is > successfully sent or not. The only difference is the timing. > > Now, while I have figured out how to get something to work, I'm left > feeling not very confident that this will stand up to the variety of > different types of input formats that I expect to convert. I am > especially concerned about the fact that if I do generate a bad file, > I do not get any kind of feedback that the file is bad (except much > later when someone calls to say that they didn't receive the fax I > thought I'd sent). Ideally, I'd like the bad fax to be sent as a good > fax but, if I can't get that, my second choice is to get a failure > response. > > I've attached an example of a good and a bad tiff file in bzip2 > files. Both were generated from the same input file using the following: > > good: > > convert "shed in field.jpg" -page letter pdf:sh7.pdf > gs -q -sDEVICE=tiffg3 -sPAPERSIZE=letter -r204x196 -dNOPAUSE > -sOutputFile="good.tif" -- "sh7.pdf" > > bad: > > convert "shed in field.jpg" pdf:sh7.pdf > gs -q -sDEVICE=tiffg3 -sPAPERSIZE=letter -r204x196 -dNOPAUSE > -sOutputFile="bad.tif" -- "sh7.pdf" > > > > I haven't included debug traces because I think this behavior can be > easily repeated on other systems. If necessary, I will provide them. > ------------------------------------------------------------------------ > > _______________________________________________ > Callweaver-users mailing list > [email protected] > http://lists.callweaver.org/mailman/listinfo/callweaver-users > _______________________________________________ Callweaver-users mailing list [email protected] http://lists.callweaver.org/mailman/listinfo/callweaver-users
