Hi All

I’m encountering a new error rendering a 3ds max 2014 v-ray 3 scene: “PNG Library Internal Error”

The first frame of each task renders ok and is saved out, but then subsequent frame creates this error at save time:

0: WARNING: Detected popup dialog “PNG Plugin”.
0: WARNING: ---- dump of dialog ----
0: WARNING: Button: OK
0: WARNING: Static: PNG Library Internal Error
0: WARNING: ---- end dump of dialog ----

I’ve had a search for tips on how to solve this but come up with nothing. Oddly enough quite a few people have also encountered this error using backburner, but with older version of max it seems.

I’ve got a list of things to test to try and fix this but if anyone sees this and can offer any help today I’d be very very grateful as have a deadline fast approaching!

thanks

Also worth mentioning that this error occurs regardless of the render output format, so even jpegs.

Hi Dave,
Few things jump to mind here, which can be discounted if not applicable to your studio setup:

1. Possibly corrupt Render Element, I know they may be saving all to another file format, but RE’s can’t be trusted! If your submitting via SMTD (inside of 3dsMax), then the “render” tab, “3dsMax Pathing Options” has a nice checkbox feature called “Rebuild Render Elements” which might help here.

2. Try restarting all your machines, perhaps one of your machines has a copy of after effects (or another app) still running, which if it has crashed, can lock the last file it was touching and if that happens to be one of your PNG files which is then referenced in your max scene that could explain it. A machine restart of all your machines will fix that or use your file server to lookup which machine has a PNG file locked into it’s machine via either currently open files.

3. If all your render output is now changed to a file format other than PNG and the error is still occuring. How about any and ALL texture files or any other input files to this max scene? Are any of them PNG files? Do they all open ok in Photoshop without any warning/error? If you have any animated PNG texture sequences coming into 3dsmax, can you try opening them up in AE or Nuke? Do they open ok, all frames of the sequence are ok?

4. For any “inputted” PNG files into your max scene file, do they all look ok, when you browse for them in Windows Explorer? Any 0kb files here? Any dodgy file sizes not in keeping with the rest of them? Anything stand out for you?

5. Worst comes to worst (and the above should hopefully narrow it down), you might be able to just suppress the PNG dialog and the renders will complete? You can do this by editing the 3dsmax.py plugin file in: “…/your_deadline_repo/plugins/3dsmax/3dsmax.py”

Look at the lines towards the bottom of the file which look like this:

[code] # Handle Generic missing plug-in DLL referenced by 3rd party software/plugin
self.AddPopupHandler( “Error Loading Plug-in DLL”, “OK” )

    # Handle Targa Image Control Pop-up Dialog
    self.AddPopupHandler( "Targa Image Control", "OK" )

    # Handle Max2015+ Desktop Analytics Program Dialog
    self.AddPopupHandler( "Desktop Analytics Program", "OK" )[/code]

and add another line (and comment line) which look like this:

# Handle PNG Plugin - [PNG Library Internal Error] self.AddPopupHandler( "PNG Plugin", "OK" )

Re-queue any failing jobs and that pop-up dialog should now have it’s “OK” button pressed automatically for you.

Let us know if anything helped to fix the issue for you.

Regards,
Mike

Hi Mike

A combination of fixes seem to have fixed the problem, unfortunately I don’t have the spare time to keep testing and find the exact cause of the issue.

The steps that fixed the issue included:
Enabled “Rebuild Render Elements” as you suggested.
Added the line of code you provided to 3dsmax.py (although this is good to know I don’t think it solved the problem)
Re-set the output path, changing it to tiff format, then back to png.

Thanks for your comprehensive answer.

Dave