I have been using PoTrace for the past few months to convert portable bitmap (PBM) files from GIMP into DXF format. Today I attempted to convert my largest PBM file to date: a 100-MB PBM file (28,476 x 28,476 pixels). Unfortunately, PoTrace created an essentially empty (1-kB) DXF output file and issued no error message. I can successfully convert 40-MB PBM files to DXF using the same potrace command-line options from the DOS/Windows command prompt. I am using PoTrace v1.1 on Windows-7.
I've attempted to debug the problem using PoTrace's "-debug 3" or "-d3" command-line options. However, no output is sent to STDOUT, and no log files are generated in the current directory.
Do you have any advice or suggestions? Specifically,
(1) Is anyone aware of fundamental PoTrace limits for the input size of PBM files?
(2) Do the debug options work when converting PBM to DXF?
Thanks in advance for suggestions.
I have found a work-around for the problem described earlier: Rather than using PBM format, I exported the same image into either PGM format (792 MB) or PPM format (2.4 GB). PoTrace was able to convert both of these *very* large bitmap files to DXF format.
I still do not know why PoTrace won't convert the "same" image in its 100-MB PBM format. But at least I can proceed with using PoTrace to create DXF files.
BTW, PoTrace is an amazing program - high quality output with very short run-times on large files! Thanks to the developers of this program!
thanks for writing. Good to know that someone is using the DXF backend. I assume you are using version 1.10, not 1.1 as stated above.
I just tried Potrace 1.10 on a PBM file of size 28476 x 28476, and I had no problems generating a DXF file from it. However, I haven't tried the Windows version (yet).
* Could you post (or send me) the offending PBM file? Since PGM apparently works, we can't rule out that there's something wrong with the PBM file, rather than Potrace.
* Do you get the same problem with other PBM files of similar size?
* Do you get the same problem if you use the same input file with a different backend (say EPS instead of DXF)? If yes, the problem is more likely with the PBM frontend, and if no, the problem is more likely with the DXF backend.
Thanks, - Peter
Thanks for the reply. While running the tests you suggested, I found that I've raised a false alarm for PoTrace (v 1.10 on Win-7).
The 100-MB PBM input file contains nothing but black pixels - at least when viewed in GIMP. I had incorrectly assumed that GIMP's PBM export plug-in was working correctly (as it had done for smaller, 40-MB PBM files). So it appears that my next bug-report will go to gimp.org.
Sorry to have wasted your time on this. Again, thanks for making PoTrace available!
Great! I'm glad it was resolved, at least as far as Potrace is concerned! - Peter
Sign up for the SourceForge newsletter:
You seem to have CSS turned off.
Please don't fill out this field.