[ffmpeg] NVENC encoding not working

Important Information

• mpv 0.34.0
• Windows 10 and 11
• Windows build by shinchiro
• stopped working with mpv 0.33.1, worked with 0.33.0

Reproduction steps

mpv 'test.mp4' '--start=0:00:00.000' '--end=0:00:16.855' --loop-file=no --no-pause --ovc=h264_nvenc --oac=aac '--o=./test.mp4-[00.00.000-00.16.855]-audio.mp4' -v --log-file=encode.log

Expected behavior

Succesful encode with NVENC

Actual behavior

Encode failing

Log file

[   0.078][i][vo/lavc] Opening encoder: NVIDIA NVENC H.264 encoder [h264_nvenc]
[   0.079][d][ffmpeg] h264_nvenc: Loaded Nvenc version 11.1
[   0.079][d][ffmpeg] h264_nvenc: Nvenc initialized successfully
[   0.090][d][ffmpeg] h264_nvenc: 1 CUDA capable devices found
[   0.090][d][ffmpeg] h264_nvenc: [ GPU #0 - < NVIDIA GeForce RTX 3060 Laptop GPU > has Compute SM 8.6 ]
[   0.200][d][ffmpeg] h264_nvenc: supports NVENC
[   0.256][v][ao] Trying audio driver 'lavc'
[   0.256][v][ao/lavc] requested format: 48000 Hz, stereo channels, floatp
[   0.256][v][ao/lavc] Channel layouts:
[   0.256][v][ao/lavc]  - anything
[   0.257][v][ao/lavc] result: stereo
[   0.257][i][ao/lavc] Opening encoder: AAC (Advanced Audio Coding) [aac]
[   0.257][i][encode] Opening output file: ./test.mp4-[00.00.000-00.16.855]-audio.mp4
[   0.258][i][encode] Opening muxer: MP4 (MPEG-4 Part 14) [mp4]
[   0.258][v][ao/lavc] device buffer: 12288 samples.
[   0.258][v][ao/lavc] using soft-buffer of 12288 samples.
[   0.258][i][cplayer] AO: [lavc] 48000Hz stereo 2ch floatp
[   0.259][v][cplayer] AO: Description: audio encoding using libavcodec
[   0.260][v][cplayer] first video frame after restart shown
[   0.260][v][af] [convert] (disabled)
[   0.260][v][af] [out] 48000Hz stereo 2ch floatp
[   0.261][v][cplayer] audio ready
[   0.261][d][cplayer] starting video playback
[   0.261][v][cplayer] delaying audio start 0.040000 vs. 0.040000, diff=0.000000
[   0.261][v][cplayer] playback restart complete @ 0.040000, audio=ready, video=playing
[   0.262][v][cplayer] starting audio playback
[   0.262][v][ao/lavc] starting AO
[   0.298][e][ffmpeg] mp4: pts (960) < dts (1917) in stream 0
[   0.298][e][encode] Writing packet failed.
[   0.299][v][cplayer] EOF code: 6  
[   0.299][d][ad] Uninit decoder.
[   0.299][d][vd] Uninit decoder.
[   0.306][d][cplayer] Terminating demuxers...
[   0.307][d][cplayer] Done terminating demuxers.
[   0.307][v][cplayer] finished playback, something happened (reason 4)
[   0.307][i][cplayer] 
[   0.309][v][ffmpeg] aac: Qavg: 2310.054
[   0.350][d][ffmpeg] h264_nvenc: Nvenc unloaded
[   0.350][d][ffmpeg] AVIOContext: Statistics: 64075 bytes written, 0 seeks, 2 writeouts
[   0.351][i][cplayer] Exiting... (Interrupted by error)
[   0.351][d][console] Exiting...
[   0.351][d][stats] Exiting...
[   0.351][d][ytdl_hook] Exiting...

Start by running the provided mpv command with test.mp4 on the stated Windows setup and inspect encode.log, especially the NVENC and muxer messages. Done means the requested H.264/AAC MP4 encode completes without the “Writing packet failed” error.