[FFmpeg-user] using nvdec ignores CFR -r in h264_nvenc decode

[Scott Freeman]

I am not sure if I am missing an option in decode (which I have none set) but I am shooting for an output file that is CFR rater than VFR. The sources are VFR.
I am using tesla M60’s on AWS with Driver Version: 418.40.04 CUDA Version: 10.1, ffmpeg version N-93469-gd0b174d7df

the cmd example is:

ffmpeg -y -probesize 50M -analyzeduration 50M -vsync 0 -hwaccel nvdec -i /tmp/myvfrfile.mp4 -nostdin -c:a aac -strict -2 -async 1 -c:v h264_nvenc -crf 20 -r 30000/1001 -pix_fmt yuv420p -movflags faststart-rtphint -c:s copy -c:d copy -map_metadata -1 -profile:v main -weightp 1 -partitions partb8x8+partp4x4+partp8x8+parti8x8 -b-pyramid 1 -weightb 1 -8x8dct 0 -fast-pskip 1 -x264-params deadzone-inter=0:deadzone-intra=0 -coder ac -trellis 1 -me_method hex -sws_flags fast_bilinear -sc_threshold 40 -keyint_min 30 -g 90 -qmin 3 -qmax 51 -qdiff 4 -sn /tmp/myoutput.mp4

 If I remove the hardware decoder, it works as expected, creating a constant frame rate file at 29.97.

Thanks for any advice,

scott