I recently upgraded to the R2 version of the Video Converter, for among other things it's support for retaining subtitles during conversion.

I'm attempting to do a conversion using the Encoding MP4 (Nvidia HVEC H265), Audio Stream: Copy 1:1. No advanced settings, no dsp effects. Just looking to do the simplest conversion. I was trying to keep the test as stock / simple as possible.

It almost immediately fails with the message: "Subtitle encoding currently only possible from text to text or bitmap to bitmap"

I enabled Debug logging and it shows this:

[7/8/2021 18:34:45] "C:\Program Files\dBpowerampVideo\ffmpeg-gpl.exe" -i "D:\Folder\Video.mkv" -map s -threads 4 -qp 24 -acodec copy -c:s mov_text -f mp4 -c:v hevc_nvenc -preset medium -y -ignore_unknown -hide_banner -progress "C:\Users\User\AppData\Local\Temp\_dbBFE3.tmp" -loglevel 16 "D:\Folder\Video- x265.tmp.mp4"
[7/8/2021 18:34:45] Encoding loop...
[7/8/2021 18:34:46] Encoding loop exit
[7/8/2021 18:34:46] Subtitle encoding currently only possible from text to text or bitmap to bitmap
[7/8/2021 18:34:46] Encoding exit

A little searching on the web makes me think this has to do with the source being .mkv and the destination being .mp4. But I'm far from well versed in ffmpeg.

I tried the same file using the Matroska (HVEC H265) for encoding and it seems like it may work. I don't care whether it's mp4 or mkv, but I'd like to use my video card for the conversion and there doesn't appear to be an encoding profile for Matroska (Nvidia HVEC H265).

I'm guessing there are a few ways the software should handle things and a combination of feature request and bug report for the new release. Hoping to spark a fix.