ffmpeg -i output.mkv -vf "psnr=stats.log" -f null - Or visually inspect frame 5000 (often a dark sietch scene):
Libvpx is the reference encoder for VP8 and VP9. Use VP9 (not VP8) for high-quality episode encodes. dune: prophecy s01e04 libvpx
ffmpeg -i "Dune.Prophecy.S01E04.mkv" -c:v libvpx-vp9 -crf 34 -b:v 0 -c:a libopus -b:a 96k -movflags +faststart output_web.webm If you didn’t intend to encode but just play S01E04 in libvpx format, use MPV or VLC 3.0+ . Avoid Windows 10/11 built-in Movies & TV app – it has poor VP9 support. ffmpeg -i output
ffmpeg -i output.mkv -vf "select='eq(n,5000)'" -vframes 1 frame5000.png | Issue | Fix | |--------|------| | Banding in dark sky/sand | Add -tile-columns 4 -row-mt 1 to enable row-based multithreading | | Grain looks blocky | Use -grain 15 (approx) – but keep low; Dune’s grain is digital | | Audio desync after encode | Use -vsync cfr -async 1 before -c:v | | Slow encoding | Add -cpu-used 2 (faster but lower quality: range 0–5) | 7. Quick Command for Web Upload (e.g., Discord/Telegram) Small file, acceptable quality for S01E04 previews: Avoid Windows 10/11 built-in Movies & TV app