svtav1
-c:v libsvtav1 -preset 10 -svtav1-params tune=0 -pix_fmt yuv420p10le -crf 45 -c:a libopus -ar 48000 -b:a 128k
低画質ならpreset8もあり。crfは25-35が妥当。45はかなり攻撃的
aomav1
-c:v libaom-av1 -preset 0 -row-mt 1 -tune vmaf_with_preprocessing -crf 40 -pix_fmt yuv420p10le
aomenc --help
-
--tune=
- Distortion metric tuned with psnr, ssim, vmaf_with_preprocessing, vmaf_without_preprocessing, vmaf, vmaf_neg, butteraugli, vmaf_saliency_map
vp9
realtimeのcrf40cpu used 5あたりでsvtav1のpreset10 crf35と同じぐらい
- -deadline
- good, best, realtime
- -cpu-used
- 0-5 or 0-8(realtime)
- 2pass: (ffmpegで使えず)
-
ffmpeg -i input.mp4 -c:v libvpx-vp9 -deadline realtime -cpu-used 6 -row-mt 1 -crf 30 -pass 1 -an -f null /dev/null && \ ffmpeg -i input.mp4 -c:v libvpx-vp9 -deadline realtime -cpu-used 6 -row-mt 1 -crf 30 -pass 2 -c:a libopus -ar 48000 -b:a 128k output.webm
-c:v libvpx-vp9 -deadline realtime -cpu-used 5 -row-mt 1 -crf 30 -b:v 0 output.webm
webp
-c:v libwebp
- -lossless
- 1 or 0
- -compression_level
- 0-6
- -quality
- 0-100 def 75
- -preset
- none
- Do not use a preset.
- default
- Use the encoder default.
- picture
- digital picture, like portrait, inner shot
- photo
- outdoor photograph, with natural lighting
- drawing
- hand or line drawing, with high-contrast details
- icon
- small-sized colorful images
- text
- text-like
webp anime
ffmpeg -i input.gif -c:v libwebp_anim -loop 0 -lossless 1 -compression_level 6 -preset icon output.webp
opus
ffmpeg -i hoge.wav -acodec libopus libopus -ab 160k -ar 48000 output.opus
avif
-c:v libsvtav1 -preset 0 -svtav1-params tune=0:film-grain=12 -still-picture 1 -pix_fmt yuv420p10le -crf 30 "$output_file" < /dev/null
svtav1は分割に時間がかかってあまり効果がなさそう
-preset 0 -crf 40 -still-picture 1 -pix_fmt yuv420p10le -color_primaries smpte432 .avif
-c:v libaom-av1 -still-picture 1 -aom-params tune=ssim:deltaq-mode=3:cpu-used=4 -pix_fmt yuv420p10le -crf 40
-pix_fmt yuv420p10le -color_primaries smpte432
- smpte432
- -display p3
- smpte431
- dci-p3
bt2020
参考: iphoneのdolby-hdr動画のカラー
- -color_trc
- arib-std-b67 (HLG)
- -color_primaries
- bt2020
- -colorspace
- bt2020nc
heif-convert
heif-convert input.HEIF output.png
うんコード
for %%f in (*.mkv) do (
ffmpeg -i "%%~f" -c:v libsvtav1 -preset 5 -crf 35 -g 600 -pix_fmt yuv420p10le -svtav1-params tune=0:film-grain=4 -c:a libopus -ac 2 -ar 48000 -b:a 128k "output\%%~nf.mkv"
)
JPEGXL
ffmpeg -i IMG_2144.JPG -effort 7 -distance 2 IMG_21442.jxl
distance 9でavif libaom preset0のcrf35より少しサイズが小さい
distance 0はロスレス distance 1は視覚的ロスレス distance 2はwebにちょうどいい
cjxl -hの結果から
- -d DISTANCE, --distance=DISTANCE
- Target visual distance in JND units, lower = higher quality. 0.0 = mathematically lossless. Default for already-lossy input (JPEG/GIF). 1.0 = visually lossless. Default for other input. Recommended range: 0.5 .. 3.0. Allowed range: 0.0 ... 25.0. Mutually exclusive with --quality.
- -q QUALITY, --quality=QUALITY
- Quality setting, higher value = higher quality. This is internally mapped to --distance. 100 = mathematically lossless. 90 = visually lossless. Quality values roughly match libjpeg quality. Recommended range: 68 .. 96. Allowed range: 0 .. 100. Mutually exclusive with --distance.
- -e EFFORT, --effort=EFFORT
- Encoder effort setting. Range: 1 .. 9. Default: 7. Higher numbers allow more computation at the expense of time. For lossless, generally it will produce smaller files. For lossy, higher effort should more accurately reach the target quality.
- 1 or ``lightning''
- 2 or ``thunder''
- 3 or ``falcon''
- 4 or ``cheetah''
- 5 or ``hare''
- 6 or ``wombat''
- 7 or ``squirrel'' (default)
- 8 or ``kitten''
- 9 or ``tortoise''
hevc
const
-c:v hevc_nvenc -preset:v p7 -profile:v main10 -rc:v constqp -rc-lookahead 1 -spatial-aq 0 -temporal-aq 1 -weighted_pred 0 -init_qpI 24 -init_qpP 24 -init_qpB 28 -qp_cb_offset 10 -qp_cr_offset 11 -b_ref_mode 1 -dpb_size 4 -multipass 1 -g 60 -bf 3 -pix_fmt yuv420p10le -c:a aac -ar 48000 -b:a 128k
constqpでは、init_qpI=n init_qpP=n init_qpB=n+4 が良い結果を出す傾向にあった。
20 20 24 24 24 28 36 36 40 38 38 42
vbr cq
-c:v hevc_nvenc -preset:v p7 -profile:v main10 -rc:v vbr -rc-lookahead 1 -spatial-aq 0 -temporal-aq 1 -weighted_pred 0 -cq 42 -b_ref_mode 1 -dpb_size 4 -multipass 1 -g 60 -bf 3 -pix_fmt yuv420p10le -c:a aac -ar 48000 -b:a 128k