VP9

• GitHub downloads
• webm wiki: VP9 Encoding Guide
• FFmpeg and VP9 Encoding Guide
• ffmpeg libvpx documentation
• VP9 Bitrate Modes in Detail - Google's
• VP9 Tips - Encoding Modes and Recommended Command Line Options - upstream's wiki
• CRF Guide (Constant Rate Factor in x264, x265 and libvpx)
• HandBrake github repo of documentation

By default, vpxenc will use 2-pass method for encoding.

To gain a CRF-type result, use –end-usage=cq –cq-level=<arg> format, and then a 1-pass encode –passes=1 Using this, vpxenc uses a default CQ of 32.

By default, HandBrake uses a CQ of 22.

HandBrake will only use 2-passes if a bitrate is set as well.

You can use ffmpeg to get a deep level of output to see what it's doing:

ffmpeg -i sample.y4m -vcodec libvpx-vp9 sample.webm

Relevant output:

[libvpx-vp9 @ 0x55a6e613e3c0]   VP8E_SET_CPUUSED:             1
[libvpx-vp9 @ 0x55a6e613e3c0]   VP8E_SET_ARNR_MAXFRAMES:      0
[libvpx-vp9 @ 0x55a6e613e3c0]   VP8E_SET_ARNR_STRENGTH:       3
[libvpx-vp9 @ 0x55a6e613e3c0]   VP8E_SET_ARNR_TYPE:           3
[libvpx-vp9 @ 0x55a6e613e3c0]   VP8E_SET_STATIC_THRESHOLD:    0
[libvpx-vp9 @ 0x55a6e613e3c0]   VP8E_SET_CQ_LEVEL:            32
[libvpx-vp9 @ 0x55a6e613e3c0]   VP9E_SET_COLOR_SPACE:         0
[libvpx-vp9 @ 0x55a6e613e3c0]   VP9E_SET_COLOR_RANGE:         0
[libvpx-vp9 @ 0x55a6e613e3c0]   VP9E_SET_TARGET_LEVEL:        255