SOLVED: Nvidia not being used for transcoding

[TheDreadPirate]

In addition to audio transcoding, it is also burning in your subtitles. Subtitle burn-in also only happens on the CPU.

GPU decodes frame --> CPU composes and renders subtitle on frame --> GPU encodes frame

But the GPU is being used for both the decode and encoding of the video.

Decoding on GPU

Code:

-hwaccel cuda

Encoding on the GPU, "h264_nvenc", with subtitle burn-in.

Code:

Stream mapping:
  Stream #0:0 (hevc) -> setparams:default (graph 0)
  Stream #0:2 (pgssub) -> scale:default (graph 0)
  overlay_cuda:default (graph 0) -> Stream #0:0 (h264_nvenc)
  Stream #0:1 -> #0:1 (aac (native) -> aac (libfdk_aac))