Need help with 2-pass TIVTC

[avurgesser]

I would like some help in troubleshooting TIVTC in two pass mode for VFR decimation of a hybrid source. Whenever I run the first pass script through VirtualDub (either for output or as video analysis pass. It only creates the tfm and tdecimate files. No lines are written to them and I see no error logs.

Windows 10.0.19042
VirtualDub2 build 44282 (32-bit)
Avisynth+ v2772 (32-bit)
TIVTC was obtained Feb 2021 through wiki link

Since I am needing to start a thread anyway, is there a cleaver and easy to manage way to toggle between 1st vs 2nd pass processing in a script (possibly by presence of the first pass output file)? I don't have a strong understanding of avs script flow control.

[jagabo]

Your post makes no sense. VirtualDub doesn't create the scripts. You create the scripts, then run them one at a time in VirtualDub. Your first pass script should look something like:

LWlibavVideoSource("filenane.mkv")
TDecimate(pass 1 arguments including output="metrics.txt")

Open the first in VirtualDub then select File -> Run Video Analysis Pass. Wait until it's done. metrix.txt will be created with all the info needed by the second pass. Then run the second pass

LWlibavVideoSource("filenane.mkv")
TDecimate(pass 2 arguments including input="metrics.txt")

With 2-pass scripts I usually put the lines for both pass in the same script and just comment out the one I don't need when running the two passes:

LWlibavVideoSource("filenane.mkv")
TDecimate(pass1 arguments including output="metrics.txt")
#TDecimate(pass 2 arguments including input="metrics.txt")

[avurgesser]

Think I found my problem. Output files are written when the script is closed, not when it has finished iterating frames. AvsPmod may have potentially been creating file access deadlock on top of that. Yuck!

Additionally I found the try/catch syntax which is serviceable for my 2-pass script needs.

try{
# second pass (will generate exception as analysis files do not exist on first pass)
}
except (x) {
# first pass (I recommend adding a subtitle to the first pass code to improve detection of errors in the second pass)
}